Trends and Evolution of Thread Lifting

Trends and Evolution of Thread Lifting

Maintaining the youthful look in our skin gets trickier with age. It’s one of the harsh realities of life. That’s why cosmetic surgery has been all the rave in recent years.

People have picked up on a new growing trend of non-invasive procedures. One of the most notable today is Thread Lifting. This procedure can be your next best solution to tighten those wrinkles and droopy cheeks.

Join me as we dive deep into this cosmetics phenomenon. We’ll explore everything you need to know about Thread Lifting and determine if it’s worth the shot.

Trends and Evolution of Thread Lifting

What Is Thread Lift?

A Thread Lift is a less-invasive cosmetics procedure that’s an alternative to facelift surgery. Also called “suture lift,” this procedure uses medical-grade sutures to lift and tighten the skin on the face or any parts of the body.

Thread Lifting is temporary and would only last for about one to three years. It is an alternative solution for people who can’t physically handle a surgical facelift.

It includes people with underlying medical conditions. It’s also for those who want a safer alternative and avoid risks that come with going under the knife.

How Does Thread Lifting Work

how-thread-lifts-work

Source from hinsdaleveinlaser

The whole process is simple. The procedure involves using thin and dissolvable sutures to pull and tighten your skin.

The needle or cannula used is thin. Nearly invisible and painless, like barbs that hold your skin in place. It keeps the threads a firm grip on the underlying tissue and muscles to pull your skin tight.

Once the threading process begins, the healing process responds. Collagen will produce on the targeted area and put more volume in your skin. It helps restore your skin’s suppleness and elasticity.

Thread Lift Procedure

Thread lift procedures may differ. It depends on the areas you will target in your thread lift. However, here’s the step-by-step process to give you a general overview of the procedure.

1. Preparation: Your Doctor will ask you to sit on the recliner before applying alcohol and topical anesthetic to the targeted area of your skin.

2. Suturing: A thin needle with equally thin threads will insert under your skin. The suturing process would take around thirty to forty-five minutes.

3. Removal: After the suturing process, they will take out the needle. You might feel a gentle pull or pressure under your skin, leaving it tight.

4. Completion: Once everything is over, your procedure is complete! You can go home and rest for a few days.

Thread Lifting: Pros & Cons

Pros

1. It’s a Quick Procedure

Believe it or not, Thread Lifting is a quick and easy procedure. Often pegged as the “Lunchtime Lift,” a regular thread lift procedure wouldn’t take more than an hour.

2. Less-Invasive

The process of thread lifting is less invasive than a conventional facelift.
It’s not messy. There’s not much need for any prodding or deep cutting. It’s a procedure that doesn’t require much effort.

Thread lifting only uses medical-grade sutures with fine dissolvable threads. While it may cause some discomfort to some, it isn’t relatively painful.

3. Has Rejuvenating Properties

Thread Lifting is also widely popular for its rejuvenating effect on the skin.
A study conducted in 2014 shows the efficacy of thread lifting rejuvenation. Its rejuvenating effects on the skin were apparent.
The researchers found that thread lifting is a safe and effective procedure for patients in need of a facelift.

4. Promotes Collagen Production

Collagen is a vital component of our skin. It’s essential in keeping the condition of the skin healthy and supple.

Collagen production decreases as we age. The process of thread lifting helps stimulate collagen production on the skin.

Some even use specialized medical-sutures that target the stimulation of collagen that forms around the thread.

5. Short Recovery Period

A regular facelift would take patients anywhere from one or three months to fully recover. A thread lift has a shorter recovery period.

Patients who underwent a thread lift may find some mild discomfort at the beginning. It includes some initial swelling or redness.
However, it would all settle after a couple of days. It won’t take a week or more to recover.

6. More Affordable Than A Conventional Face Lift

Since thread lifting is a simple procedure, it’s more affordable compared to a conventional facelift.
General anesthetics aren’t required either. It makes this procedure even more accessible to the public with its price range.

7. Lower Risk Of Complications

Traditional facelift surgeries come with all sorts of risks and probable complications.
Thread lifting would spare people from the risk of deep scarring or infection that often happens in conventional cosmetic surgeries.

It doesn’t mean that thread lifting is a hundred percent safe either. However, it’s the safest alternative you can get compared to traditional facelift surgery.

Cons

1. It’s Temporary

No matter how you look at it, getting a thread lift isn’t a one-way ticket for the long-haul. It also says the same for any cosmetic procedure.

However, conventional facelifts are more likely to give long-lasting results. Up to a decade at most.
A thread lift is temporary. It would only last for around one to three years. Besides, it won’t take much effort from patients to have a repeat thread lift procedure.

2. It’s Not For Everyone

While anyone above legal age can undertake this procedure, it’s best to note that it might not meet the ideal look everyone has in mind.

Since thread lifts are touch-ups, the improvements would be more subtle. And while many see this as an advantage, it would do poorly for people with severe cases of loose skin.

Types Of Threads

Places threads  lift treat

There are three types of threads used for thread lifting:

1. Mono Thread
Mono threads are smooth barb-less threads. It is mostly used on the under eyes, forehead, and neck to eliminate sagginess.

Mono threads are often used on the face and require an anchoring point. It has a unique way of boosting collagen formation around the mono thread.

It makes a decent thread for skin tightening and promoting collagen production. However, it’s not as effective in generating an actual “lift” to the face.

2. Screw or Tornado Thread
Screw or Tornado threads are a great volumizer in sunken-areas around the skin. They are formed usually with one or two threads intertwined together around the needle.

Tornado threads are also more effective in face lifting since the intertwined singular threads have a stronger hold.

3. Cog Thread
Cog threads are similar to mono threads. However, unlike mono threads, they have barbs and don’t require anchoring points.

The barb of the cog thread is either molded or cut. Collagen tends to form around both the barbs and threads.

It supports the structure and lifts the sagging tissues of the skin. It’s an ideal thread for lifting and sculpting the jawline.

Material Of Thread Lift

1. PDO

  • Biodegradation Period: 6 – 8 months.
  • Safety: High
  • Discomfort: Slight
  • Flexibility: Average
  • Hydrolytic Resolution: Average

Polydioxanone or PDO is an absorbable polymer. The material is durable and quite flexible and has a less-invasive lifting effect.

Its ability to rebuild tissue and induce collagen formation which makes it a popular material used for suture surgeries. It will take six months before the PDO threads are dissolved completely and absorbed into the skin. Once absorbed into the skin, it will continue to aid in boosting collagen production until 12 months.

PDO threads give your skin a subtle lift. It’s efficient in reducing wrinkles and fine lines in targeted areas. They are suitable material for individuals who want to delay the effects of aging and treat saggy skin.

2. PLLA

  • Biodegradation Period: 14 – 18 months.
  • Safety: High
  • Discomfort: Strong
  • Flexibility: Low
  • Hydrolytic Resolution: Average

Poly-Lactic Acid or PLLA is another popular material used for surgical sutures. PLLA contains all-natural components. Once the material dissolves, it breaks down into glucose, carbon dioxide, lactate, and water.

PLLA is also an alternative material for fillers. Its ability to stimulate both Type 1 and Type 2 collagen makes it more efficient in restoring the skin’s natural volume. It also provides a more effective collagen-inducing effect compared to PDO. Unlike PDO, PPLA threads barely cause an inflammatory reaction to the skin.

Since the material lasts longer, it promotes long-term benefits in restoring the skin to its youthful glow.

3. PCL

  • Biodegradation Period: 16 – 24 months.
  • Safety: High
  • Discomfort: No Discomfort
  • Flexibility: High
  • Hydrolytic Resolution: High

Polycaprolactone or PCL are absorbable and long-lasting sutures used for thread lifting. PCL is both flexible and durable. While PCL isn’t as popular as PDO and PPLA, the material is longer-lasting. The chemical bonds of PCL are very durable and quite complex. They have a slower degradation rate and can last more than two years.

PCL is also known to be more effective in boosting collagen production. It can increase the production of hyaluronic acid and type one and type two collagen.

Once it dissolves, its effects will last up to a year. It’s an ideal material for reaping the long-term benefits of thread lifting.

How Much Does A Thread Lift Cost

While it is considered cheaper than a traditional facelift procedure, it still has a hefty price point. The average cost of thread lift is around $2,250.00 on average. It can even range up to $6000.00. It depends on the entire scope of the procedure since the treatment is customizable. 

Thread lifting isn’t covered by insurance since it is considered an elective cosmetic procedure.

You need to identify the factors that can affect the cost of your thread lift:

  • Your provider’s level of service and expertise
  • The location of your provider
  • The size or number of areas treated.

How Long Does Thread Lift Last

Similar to other cosmetic procedures, a thread lift is temporary. The longevity of thread lifts heavily relies on the materials used in the procedure. Generally, a thread lift can only last for around one to three years, while a traditional facelift surgery lasts for ten years.

However, thread lift procedures are quick and easy. Maintenance wouldn’t be an issue. People who do get the treatment have no problem going for a repeat session.

In most cases, doctors encourage their patients for a repeat session every six to twelve months.

Thread Lift Complications

While thread lifting is the safer alternative for facelifts, it’s vital to note that there are still risks involved:

1. Discomfort
While thread lifting is less-invasive than facelifts, it can still cause some discomfort; both during and after the procedure.

2. Post-procedural Swelling, Bruising & Soreness
It’s normal to have a bit of swelling or mild soreness after the procedure.

However, how the body reacts to the procedure differs from person to person. So it might be worse and even uncomfortable to some.

3. Infection
Infection can still occur. More likely if you had your thread lift done by someone who is not a professional.

An infection will most likely happen if the sutures used aren’t sterile.

It’s best to choose your provider carefully for your safety.

4. Hematoma
A hematoma occurs when the walls of your blood vessels become damaged by an inexperienced practitioner.

It would cause blood to seep out around the area during the procedure. It is rare for the hematoma to occur. But it can still happen.

5. Asymmetry of the Face
Facial asymmetry can most likely happen after a thread lift.

It can be due to an insufficient lift on one side, anesthetic, or facial asymmetry that could already be inherent.

A more common irregularity is in the oral angle areas where a “sunken cheek” might occur.

Do’s and Dont’s After Thread Lift

1. Protect Your Skin
Since your skin is most likely sensitive from your procedure, an extra layer of protection is needed. You can use a sunscreen that’s recommended by your dermatologist.

Keep in mind and not rub it in on your face. Apply it gently on your skin. As much as possible, try to avoid direct exposure to sunlight.

2. Avoid Extreme Temperatures
Try to avoid exposing your newly rejuvenated skin to harsh or extreme temperatures. It’s simply not allowed. Doing so can compromise your treatment and your healing process.

3. Follow Up With Your Doctor
It’s vital to keep tabs on your doctor after the procedure.

You can reach out as early as a week after your procedure. Your doctor will assess the progress of your treatment.

4. Don’t Apply Pressure On Your Face
The last thing you’d want out of your procedure is to compromise your treatment by accidentally sleeping on your face.

Try to get used to sleeping on your back before your thread lift. You can also build a pillow fort on your sides to prevent the toss and turns you might do in your sleep.

5. Don’t Put Make-up or Other Cosmetic Products
In the first 12 hours after your procedure, try not to wear make-up or any product on your face. It could potentially damage your skin.

Your skin is sensitive after the treatment. Putting products on your face would only cause unwanted irritation.

6. Don’t Smoke or Drink Alcohol
Try to avoid doing vices such as smoking or drinking after your treatment.

Both can elevate your blood pressure. High blood pressure would compromise the flow of the nutrients your skin needs during the healing process.

7. Don’t Engage in Any Workouts Yet
During post-procedure, you should avoid doing any intense workouts.

Exercise has a way of elevating your blood pressure. Try to keep your activity level to low-impact activities, like walking.

Summary

Thread Lifting can be the best solution for chasing the fine lines and wrinkles away. Its subtle health-boosting changes make it a worthy procedure to try.

It’s important to remember that there are still limitations to this procedure. It can’t do any drastic changes to your face the way a traditional facelift can.

However, not many people can handle invasive procedures that are both risky and expensive. It has opened a door for people who want a safer and convenient way to improve their skin. It is a genuinely good investment for your health and well-being. 

The Future of Organ Transplants: Bioprinting, Stem Cells and More

The Future of Organ Transplants: Bioprinting, Stem Cells and More

The Future of Organ Transplants: Bioprinting, Stem Cells and More

In the United States alone, over 100,000 people are on the organ transplant list. Around 17 of these people will die per day without having received the transplant. It’s clear that organs from human donors will never be adequate for everyone looking for a transplant. Thus, scientists have been researching alternatives, such as using organs made from repurposed stem cells, animal organs, and bioprinted (3D-printed) organs.

In this article, we explore the future of organ transplants. The article attempts to answer frequently asked questions about technologies, such as human organ 3D bioprinting, how close humanity is to bioprinting internal human organs, and if humans have successfully 3D-printed organ transplants yet.

Improving Technology to Deliver Healthcare

In an article published by The NIH’s National Library of Medicine, Marilia Cascalho, Brenda M. Ogle, and Jeffrey L. Platt conclude that “the need for organ replacement not only exceeds by far the supply of organs available for transplantation, but the need is also likely to increase dramatically.”
Conscious of the reality presented by Ogle and others, scientists are turning to technology for new and innovative ways to deliver therapy and organs faster to those who need them.

Writing for the technology website ZDNet.com, Jo Best cites the principal investigator at Penn State University, Dr. Ibrahim Ozbolat, who says, “
Bioprinting has great promise -it has a lot of advantages and capabilities. Of course, it’s not really perfect yet, but despite that, we have all these good things going on in the field.”

Although the technology is not perfect yet, 3D printing looks like it is the future of medical technology. From 3D-printed drugs to 3D-printed organs, a technology that has its roots in manufacturing is rapidly branching into the medical field. The use cases of bioprinting are extensive. Scientists have bioprinted drugs, external human body parts, and even human internal organs.

Central to scientists’ technologies to deliver better healthcare through technologies like 3D bioprinting is the need to develop environmentally-friendly and biodegradable ways to deliver drugs and health services.

What is Human Organ Printing?

organs printed

Bioprinting (also known as 3D bioprinting) is the combined use of biomaterials like cells and growth factors (naturally occurring substances that can stimulate cells’ production) to create structures that resemble body tissues. Bioprinting is an additive manufacturing process, implying that material is added to create something instead of starting with a block of material from which you need to remove parts to create an item.

The first step in bioprinting is the creation of a digital model of the tissue to be printed. This is followed by a layer-by-layer printing of the target tissue. The organs created through bioprinting are called engineered organs.

In a 2017 article published by the peer-reviewed literature repository, ScienceDirect.com, Elliot S Bishop, and several other authors note that there are generally three core perspectives to bioprinting. These are biomimicry, autonomous self-assembly, and the microtissue-based method. While none of these three approaches is exclusive to bioprinting, they can be applied, at different levels, based on parameters like target tissue type, user experience, and printing method.

Let’s take a closer look at the three bioprinting core perspectives in greater detail:

Biomimicry

Biomimicry involves the conceptual reduction of tissue to its simplest parts to make the building up process easier. According to the Biomimicry Institute, “Biomimicry offers an empathetic, interconnected understanding of how life works and, ultimately, where we fit in.” It adds, “We can use biomimicry to not only learn from nature’s wisdom but also heal ourselves — and this planet — in the process.”

The first step involves selecting an appropriate scaffold material that most resembles the target tissue in structural and mechanical properties.

The second and final step in biomimicry is the use of bioreactors. These simulate an environment similar to that of the target tissue. Bioreactors are often used after tissue printing, during the period where the tissue is allowed to mature.

Autonomous Self-assembly

Autonomous self-assembly mimics a cell’s creation through an autonomous organization that involves no external intervention. Autonomic self-assembly does not rely on scaffolding.

In an article published by the NIH’s National Library of Medicine, Karoly Jakab and a group of other authors say that the autonomous self-assembly principle is based on the assumption that “living organisms, particularly the developing embryo, are quintessential self-organizing systems.”

The main advantage of autonomous self-assembly is that it produces organs with high cellular density, better cellular interactions, faster growth, and better long-term function.

Microtissue

Bishop and others note that “the concept of a microtissue approach to bioprinting relies on the fact that a typical complex in vivo tissue is composed of many simpler units whose combined structure and function contribute to the overall whole.” This bioprinting method also involves creating the organ without the need for a scaffold.

According to Bishop and others, the main advantage of using the microtissue approach is that it results in “accelerated rates of ECM [extracellular matrix] production, maturation, and differentiation of vascular tissue.”

What are the Benefits of 3D Organ Printing?

The main advantage of bioprinting is that it could accelerate human organ production so that people who need organs do not have to wait too long before they can access them. Even though human donors will still play an essential part in providing organs, the 3D organ printing technologies will be much-needed alternatives to ensure that no-one dies in the future waiting for organ transplants.

Writing for the NIH Director’s Blog, Dr. Francis Collins states that one of the main advantages of 3D organ printing is that it relies on the host person’s cells as the foundation for the new organ.
In an article produced for NBCNews.com, Sony Salzman proposes that, as the 3D organ printing technology gets better, it will become less likely that the host’s body will reject any organs produced for transplants.

As a general concept, bioprinting could result in humans gaining a better understanding of how nature works. This could result in human beings coming up with better ways to repair the damage caused by some of our environmentally-unfriendly actions. It makes it possible to consider ways of sustainable healthcare services and drug delivery.

How Close are we to Bioprinting Internal Organs?

A group of researchers from the Singapore University of Technology and Design (SUTD), Nanyang Technological University (NTU), and Asia University published a paper entitled, Print me an organ: Why are we not there yet? According to Professor Chua Chee Kai, a researcher at SUTD and lead author of the paper, “While 3D bioprinting is still in its early stages, the remarkable leap it has made in recent years points to the eventual reality of lab-grown, functional organs.” This suggests that a future where bioprinted internal organs are commonplace is inevitable.

Even though the use of transplantable fully-functional human internal organs is not yet common, Emma Yasinski, a science and medical journalist, is optimistic. She believes that “scientists are getting closer, making pieces of tissue that can be used to test drugs, and designing methods to overcome the challenges of recreating the body’s complex biology.”

Researchers have come as far as producing an organ similar to a human lung. Bioengineers achieved this at the University of Washington and Rice University. The technology used is called stereolithography apparatus for tissue engineering (SLATE). It is an open-source bioprinting technology used to create an organ that could sustain normal blood pressure and mimic breathing movements.

What Body Parts Can be 3D-Printed?

human brain printed

According to a website that brings together manufacturers of medical devices, MedicalDevice-Network.com, bones, corneas, cartilage, hearts, and skin have all been 3D-printed to varying degrees of success.

The Times of Israel reports that researchers from the University of Israel unveiled a 3D-printed heart made from human tissue in April 2019. The same paper reports this was the first artificial heart to have blood vessels, cells, chambers, and ventricles. It took between three to four hours to print the heart.

The world’s largest international online media platform on 3D printing and its applications, 3Dnatives.com, reports that the Director of the Wake Forest Institute for Regenerative Medicine, Professor Anthony Atala, unveiled a bioprinted kidney in 2011. The kidney was designed from stem cells in seven hours but could not live for very long.

3Dnatives also reports that ovaries, a mini liver, an ear, and a pancreas have also been bioprinted recently. This shows that even though there may still be issues with 3D bioprinted organs, the possibility of printing even the most intricate human organ is becoming a given.

Researchers in Groningen in the Netherlands have successfully bioprinted an antibacterial tooth. The tooth’s antibacterial abilities were tested against Streptococcus mutans (a bacteria commonly found in humans’ oral cavity) in a saliva solution. Ninety-nine percent of the bacteria were killed.

What Was the First 3D-Printed Organ?

According to an article published by the website that provides answers to some of the world’s most common questions, HowStuffWorks.com, a synthetic human bladder was developed in 1999 by scientists at the Wake Forest Institute for Regenerative Medicine. It was created using a synthetic scaffold coated with cells taken from the target patient. Cells from the target patient were required to minimize the patient’s body’s chances of rejecting the synthesized organ.

Dr. Gabor Forgacs pioneered the research that led to the first successful 3D-printed organ. He started by observing cell behavior and discovered that the cells could fuse into entirely novel, spatial structures. Perhaps all of this would not have been made possible without the work of Charles W. Hull (Chuck) in 1984. Hull was the researcher who developed a stereolithography method (a 3D printing process that creates concept models and prototypes).

Have There Been Successful 3D-Printed Organ Transplants?

Most of the 3D-printed human organs have not been fully functional, but there have been a few successful transplants. As mentioned earlier, the scientists at the Wake Forest Institute for Regenerative Medicine printed and transplanted an artificial scaffold for a human bladder.

Currently, there are about ten people who have transplanted bladders made from their own cells.
According to EBioMedicine, a publication of TheLancet.com, patients living with microtia has also had transplants done successfully. Microtia is a condition that causes the deformation of an individual’s external ear.

In China, five children living with microtia underwent successful bioprinted ear transplants. The artificial ears were made using cells from the patients’ bodies. The five children were observed for two and a half years, and the results were encouraging. Although two of the five patients had some issues with their new ears, the rest did not report any issues.

In 2016, a two-year-old girl from Queensland, Maia Van Mulligan, was born with only one ear and was put on a list for an ear transplant. On December 20, 2018, she had her missing ear successfully reconstructed thanks to 3D printing.

Using Animal Organs

Macro eye photo

Apart from 3D bioprinting, there are ongoing efforts in gene-editing technology to make it possible to transplant animal organs into human beings. Writing for the British publication, TheGuardian.com, Karen Weintraub says that it is no longer a question of if, but rather when this could happen.

In 2019, Weintraub reported that “researchers in South Korea are expected to transplant pig corneas into humans within a year.” She adds, “A handful of groups across the U.S. are also working toward pig organ clinical trials in the next few years, including a group at Massachusetts General Hospital in Boston that is starting a six-person clinical trial using “blankets” of pigskin to temporarily protect the skin of burn victims.”

While Marlon F. Levy, a medical doctor working at the Baylor University Medical Center, Dallas, Texas, accepts that there has been much progress in getting closer to animal-to-human transplants, he accepts that the clinical application process still needs to consider several issues within the field of genetics.

Beginner’s Guide with PLGA Sterilization

Beginner’s Guide with PLGA Sterilization

Beginner’s Guide with PLGA Sterilization

The sterilization process is a process that requires regular verification and key control in the production process of medical devices. The purpose of product sterilization is to make the product free of any type of surviving microorganisms. As the most used biodegradable polymer, PLGA also needs to be sterilization before use.

In this post, we will explain three common using methods, Including sterilization principles and influencing factors.

1. Ethylene oxide

1. Ethylene oxide Sterilization

Ethylene oxide is a chemical substance. It is a colorless gas under normal temperature and pressure. It has a lively chemical property and can react with many substances.

When Ethylene oxide meets water, it reacts slowly to form ethylene glycol. Ethylene oxide has strong penetrating power and good diffusivity, it can penetrate packaging materials such as kraft paper, polyester film, polyethylene, and polyvinyl chloride film, which is beneficial to sterilization and preservation of articles.

The mechanism of action of ethylene oxide to kill various microorganisms is mainly alkylation, and the sites of action are thiol (-SH), amino (-NH2), carboxyl (-COOH), and hydroxyl in protein and nucleic acid molecules. (-OH) etc. Ethylene oxide can cause these groups to undergo an alkylation reaction, which makes microorganisms and biological macromolecules lose their activity, thereby killing microorganisms. 

The main factors of the ethylene oxide sterilization effect are temperature, concentration, humidity, sterilization time, etc. Since ethylene oxide sterilization is a chemical reaction, its reaction rate is related to temperature. It is not that the higher the temperature, the better.

On the one hand, considering the product’s resistance to temperature, on the other hand, excessively high-temperature requirements will increase the cost of sterilization equipment. Therefore, the most common sterilization temperature is about 50 ℃.

Humidity plays an important role in the ethylene oxide sterilization process. It is generally believed that the role of humidity has two aspects. On the one hand, the reaction of ethylene oxide with dehydrated bacterial spores requires a certain amount of water; on the other hand, water can enhance the environment. The permeability of oxyethane makes it easier to penetrate the packaging of medical devices.

2. Irradiation Sterilization

2. Radiation

Radiation sterilization, also known as ionizing radiation sterilization, is based on radiation processing technology and uses high-energy rays generated by electric radiation such as x-rays, gamma rays, or high-speed electron beams to produce powerful physical effects in the process of energy transfer and transfer.

And biological effects, to achieve the purpose of insecticide, sterilization, and physiological processes.

The principle is mainly to destroy the DNA and RNA in the bacterial cells, the damaged DNA and RNA molecules are degraded, and the protein synthesis and genetic functions are lost, causing the cell to die.

Irradiation dose Sterilization dose refers to the absorbed dose that reaches the required sterilization assurance level (SAL), and the sterilization assurance level refers to the maximum expected probability that the product will be in a bacterial state after an effective sterilization process.

For radiation sterilization, the number of inactivated microorganisms follows the law of exponential inactivation. This means that no matter how big the dose is, the microorganisms have a corresponding chance of survival.

3. Moist heat sterilization

3. Moist heat sterilization

Moist heat sterilization can be divided into high-pressure steam sterilization, boiling, pasteurization, and ultra-high temperature sterilization.

The high-pressure steam sterilization method heats water to produce steam and uses the latent heat energy released by saturated steam to kill all microorganisms in the articles to be sterilized under specific conditions (pressure, temperature, time, etc.) through special equipment to achieve no The purpose of bacteria.

High-pressure steam sterilization has strong sterilization ability and is the most effective and widely used sterilization method in thermodynamic sterilization. Medicines, containers, culture media, sterile coats, rubber stoppers, and other items that will not change or be damaged when exposed to high temperature and humidity can all be sterilized by this method.

Summary

Final word

The three commonly used sterilization methods have corresponding limitations. Medical device companies can choose the best sterilization method based on product materials, packaging methods, and other unfavorable sterilization factors to improve the quality of products after sterilization and reduce costs.

Based on the above-mentioned sterilization theory, the influencing factors of the three polymer material medical device sterilization methods can be optimized, and the optimal sterilization process parameters can be determined.

Ultimate Guide to Electrospinning

Ultimate Guide to Electrospinning

Ultimate Guide to Electrospinning

While there is no shortage of new and innovative technologies being explored nowadays, we find few of them as exciting as nanofibers. From tissue reconstruction to more effective and compact filters for air pollutants, there is a lot of potential for this up and coming technology. Electrospinning is the most commonly used process to create these nanofibers. What exactly is electrospinning and why is it the method of choice?

In this post, we will explain all the fact with this technology, such as the process, material avaiable.

electrospinning

What is electrospinning?

In electrospinning, a voltage is applied to a controlled flow of a polymer solution. This is typically done by ejecting the polymer solution through a spinneret or a metal syringe needle connected to a power source. When sufficient charge has accumulated on the droplet of liquid, it ejects automatically via electrostatic repulsion. This changes the shape of the droplet into a characteristic “Taylor cone” and stretches the liquid into a very thin fiber. Fibers made via electrospinning typically have diameters in the sub-micrometer to the nanometer scale.

Drying of the polymer solution is achieved almost instantaneously during this phase because of the fiber’s high surface area-to-mass ratio. Further elongation of the fiber happens via continuous electrostatic repulsion until they accumulate on a grounded collector plate or drum.

Several parameters, such as the type of polymer solution used and the applied voltage intensity, can be varied to control the characteristics of the nanofiber created via electrospinning. Today, electrospinning is the most common method for nanofiber production and is practiced in both laboratory and industrial-scale applications.

History of electrospinning

The basic phenomenon behind electrospinning was first observed way back in the 16th century by William Gilbert when he noted how a water droplet formed a characteristic cone shape when it came near a charged surface. Refining this concept further into electrospinning was first done in the late 1800s and patented by 1902.

By the 1930s and 1940s, efforts to scale up the electrospinning process for commercial and industrial use were underway. John Zeleny pioneered the use of metal capillaries while C.L. Norton developed a method for using polymer melts instead of solutions. Patents for the use of electrospinning technology to produce textile yarns were also filed during this period.

The first commercial-scale use of electrospinning produced the “Battlefield Filter,” a smoke filter element developed by the Aerosol Laboratory of the L. Ya. Karpov Institute and manufactured in the Russian city of Tver. Made from a cellulose acetate material, the so-called “BF” filter reached a throughput of 20 million square meters per annum by the 1960s.

The “Taylor cone” was a term coined by Sir Geoffrey Ingram Taylor in the 1960s. By mathematically modeling the response of a fluid droplet to an electric field, Taylor was one of the first few scientists who started developing a theoretical understanding of the electrospinning process.

In the late 1980s, more intensive laboratory studies on electrospinning aimed to use the technology to create fibers in the sub-micrometer and nanometer scales. Early success in the use of electrospinning to cell culture and tissue engineering opened the floodgates for more thorough scientific studies on the topic. Since the early 1990s, it has been claimed that scientific publications about electrospinning seemed to have grown exponentially year to year.

What is electrospinning used for?

Nowadays, work on electrospinning is no longer restricted to laboratory research. Due to their uniquely high porosity and surface-area-to-volume ratio, the nanofibers created through electrospinning have made their way into several biological, commercial, and industrial applications.

1. Drug delivery

Several groups have invested considerable effort into using electrospun materials for enhanced drug delivery systems. Compared to more traditional drug delivery vesicles, electrospun materials provide more degrees of freedom in terms of surface-area-to-volume, allowing for higher drug-loading capacities. In terms of materials, it is possible to use typical biocompatible polymers such as gelatin and alginate for the electrospinning process.

Antibiotic treatment is considered one of the foremost pharmaceutical fields where electrospinning can be valuable. There are two approaches to incorporating drugs into electrospun materials – they can either be coated on the fibers or incorporated directly into the polymer solution.

In any case, the goal is to deliver a higher concentration of the drugs which will then be released over a longer period of time. Initial results have been promising. In a study conducted in 2007, an antibiotic coated on a polycaprolactone (PCL) membrane resulted in an 80% release over the first three hours, with the residual drug releasing over the next 18 hours.

drug delivery

2. Tissue engineering

In the field of tissue engineering, nanospun materials are used to mimic the characteristics of an extracellular matrix. These nanofiber scaffolds act as supports for cell growth, and eventually, tissue regeneration. Again, the compatibility of electrospinning with biocompatible materials makes it ideal for producing scaffolds that can be safely resorbed into the body.

Copious levels of research have been dedicated to developing electrospinning methods to aid the recovery of muscles, ligaments, bone tissue, skin, and blood vessels. There are still some challenges such as the difficulty of creating thick scaffolds via electrospinning. Electrospun meshes also do not provide the best medium for cell infiltration on account of their very small pores.

3. Food packaging

It may seem counter-intuitive to use a porous material created via electrospinning as food packaging. However, research into this particular application has focused on the integration of beneficial active compounds into an electrospun mesh. Thus, packaging material can be enhanced to be less susceptible to deterioration by moisture, oxidation, and temperature. There have also been studies in the incorporation of nutraceuticals or antimicrobials into food packaging, which should also help improve the shelf life of food products.

The biggest challenge for this application is the lack of reproducibility of creating nanofiber meshes, especially for large-scale production. Even when going through the same process, there is an element of randomness in how fibers will be positioned and oriented within the mesh. This lack of predictability in terms of the performance of the final product can be problematic when dealing with matters as finicky as food packaging.

4. Textile treatment

Nanofiber treatment in textiles has been explored as a way to develop a fabric that is waterproof, yet breathable. The idea is to create a densely woven layer of electrospun nanofibers as a treatment for standard fabrics, providing water-resistance without compromising the fabric’s breathability. The small pores provide better resistance to water penetration but maintain better air permeability compared to fabric that has been laminated or coated with a waterproof substance. This technology has a lot of potential applications from camping and outdoor gear to standard, everyday wear.

5. Solar cells and energy storage

Solar power is at the forefront of the energy transition movement nowadays, and nanofiber technology is being explored as a way to address one of its most problematic aspects – efficiency. Electrospun nanofibers integrated into solar panels provide a higher surface area and porosity, thus maximizing light absorption and improving the efficiency of conversion of photoelectric energy.

Energy storage pretty much goes hand-in-hand with solar power generation, given that solar on its own cannot provide baseload energy. Electrospun fibers can also be beneficial in this regard. Studies conducted on the use of carbon nanofibers as cathode material for lithium-air batteries indicate that they can provide higher storage capacities and power densities.

6. Air filtration

Given how electrospun fibers were first commercially used as filter materials, it’s not surprising that this field of application for electrospinning persists today. Compared to both activated carbon and cellulose filter media, nanospun fiber meshes exhibited higher removal of volatile organic compounds and microscopic dust particles. In the medical field, it has also been concluded that the pores of nanofiber filters can effectively reduce the intake of bacteria, viruses, and allergens by up to 99.9%

Advantages of electrospinning technology

Electrospinning may be the most common method to produce nanofibers, but there are also alternatives such as drawing, freeze-drying, phase separation, and self-assembly. While we won’t go into the details of how each method works, we can look at the benefits of electrospinning to understand why it is the method of choice.

  • Relatively inexpensive

Compared to other means of nanofiber production, electrospinning is a relatively simple and inexpensive method. The equipment needed to do electrospinning does not need to have a large footprint, making it more friendly for laboratory-scale settings. This is likely also part of the reason why electrospinning has been more thoroughly studied than any other nanofiber technology.

  • Produces finer fibers

Electrospinning provides a lot of opportunities for controlling the morphology of the fiber or mesh being produced. By adjusting the voltage bias between the spinneret and the collector, the diameter of the resulting fiber can be increased or decreased. Moreover, the dependence on electrostatic repulsion to pull the polymer material into fibers allows for smaller diameter fibers compared to methods like drawing that relied on more mechanical forces.

  • Versatile material compatibility

Unlike other methods, electrospinning can create nanofibers out of just about any type of polymer provided that they have sufficiently high molecular weights. This is in contrast to methods that can work only with high-viscosity solutions.

Despite the benefits, electrospinning is not quite a perfect method. The random manner in which fibers deposit on the grounded collector makes reproducibility a challenge, and it’s very difficult to electrospin thick or large-volume scaffolds.

electrospinning process

Electrospinning processes

The electrospinning process is fairly simple but still has room for parameters to be tweaked. These parameters include voltage applied to the spinneret, the flowrate of the polymer solution, the diameter of the opening of the spinneret, the distance between the needle and the collector, the type of grounded collector. Changing any of these parameters can have profound effects on the density of the resulting mesh, the diameter of the fibers, and the geometry by which the individual fibers build the mesh.

In a typical electrospinning setup, the polymer solution is contained inside an enclosed container that extrudes towards a metallic syringe or pipette. A piston controlled to a metering pump provides control over the rate at which the solution is extruded through the pipette.

A power supply connected to the metallic syringe or pipette is responsible for carrying a charge to the polymer solution. Power output is typically high – somewhere in the range of 5 to 30 kV. At the minimum, the charge has to be enough for electrostatic repulsion to overcome the fluid’s surface tension. For most polymer solutions, the value of this surface tension is somewhere between 20 to 40 N/m2.

The electrostatic repulsion results in the gradual drawing of the polymer solution and the liquid droplet taking the characteristic “Taylor cone” shape. The solvent almost instantaneously evaporates during this phase as the polymer elongates at very high strain rates.

This stream initially takes a linear path but is disrupted as it travels closer to the grounded collector. This instability is caused by electrostatic repulsion as charges accumulate on various bends in the fiber. These random movements approximate a spiral shape, which helps further stretch the fibers.

Electrospinning setups can have grounded collectors that are either stationary or rotating. Rotating collectors help in creating meshes that have more aligned fibers, while static collectors maximize the randomness of the fiber alignment. Each option has benefits and drawbacks in terms of the pore size and mechanical integrity of the resultant nanofiber mesh.

Electrospinning materials

Depending on the intended application, nanofibers produced via electrospinning can be created from either natural or synthetic polymers.  This versatility in compatible source materials is one of the greatest strengths of the electrospinning process. The following is a short list of the most commonly used polymers in electrospinning:

Natural polymers:

  • Collagen
  • Chitosan
  • Fibrine
  • Gelatin
  • Keratin

Synthetic polymers:

Final word

Nanofiber technology has proven to be one of the most exciting fields of research in the past few years. As the primary method for creating nanofibers, electrospinning is as equally interesting. Despite being fairly simple in principle, electrospinning is an extremely adaptable technique and is economical for both commercial production and lab-scale studies.

PLLA vs PDLA vs PDLLA

PLLA vs PDLA vs PDLLA

PLLA vs PDLA vs PDLLA

Although PLA is one of the most commonly used materials in 3D printing and one of the most popular bioplastics, not many people know that there is more than one type of PLA out there.

Variations of PLA are mostly based on the ways in which its chemical structure can be altered. The differences may be subtle, but they are significant enough for a few industries and are certainly worth discussing.

chemistry

Lactic acid as a chiral molecule

Before jumping into the different types of polymer chains that exist for PLA, we need to look at the molecular structure of its constituent monomer – lactic acid. Lactic acid is produced by fermentation of carbohydrate compounds which are typically derived from plant-based material, giving PLA its unique character as a more “sustainable” plastic.

The chemical composition of lactic acid does not change – each unit of lactic acid contains exactly three molecules of carbon, three molecules of oxygen, and six molecules of hydrogen which are connected in a manner that creates specific functional groups. However, there can be variations in how these molecules are oriented in three-dimensional space.

Lactic acid is what is known as a chiral molecule. This means its molecular structure has two mirror images that are distinct from each other. These mirror images are called enantiomers or optical isomers.

To distinguish between these optical isomers, they are commonly referred to as either the L (laevorotatory) or the D (dextrorotatory) isomers based on the direction at which they polarize light.

In the case of lactic acid, its optical isomers are called L-lactic acid and D-lactic acid. A mixture of the optical isomers can also be concocted, which is referred to as a racemic mixture of simply DL-lactic acid.

The process by which lactic acid is created, including the bacteria used for fermentation, can have pronounced effects on which type of isomer lactic acid isomer is produced. Controlling these factors is important because these isomers can have distinct characteristics – for instance, both L-lactic acid and D-lactic acid have a freezing point that’s higher than DL-lactic acid.

PLLA vs PDLA vs PDLLA

As we’ve mentioned, different isomers of lactic acid can have different chemical and physical properties. These differences also translate to their corresponding polymer products. Considering the concept of chirality, we now know there are also three possible PLA polymer chains:

Crystallization

Both PLLA and PDLA can be manufactured by having pure mixtures of either L-lactic acid or D-lactic acid undergo a condensation reaction to produce long polymer chains. Both PLLA and PDLA polymers are naturally crystalline, which means that they take on ordered molecular structures.

PDLLA is created by polymerizing a mixture of both L-lactic acid and D-lactic acid. A 1:1 ratio of both isomers is typically used, the degree of crystallinity of the final polymer can be altered by tweaking with this ratio. In general, however, PDLLA is less crystalline and more amorphous than its PLLA and PDLA counterparts.

Solubility

The crystalline nature of both PLLA and PDLA gives them almost similar characteristics. They have melting temperatures somewhere within the 170 °C to 180 °C range and are selectively soluble. Crystalline PLLA does not dissolve in many common solvents like acetone, ethyl acetate, and tetrahydrofuran (THF).

On the other hand, PDLA does not decompose when exposed to certain enzymes that can hydrolyze both PLLA and PDLLA.

Properties

PDLLA is produced by the copolymerization of L-lactic acid and D-lactic acid or their lactide counterparts. When combined in a 1:1 ratio, the resulting PDLLA becomes an amorphous material with a glass transition temperature of 50 to 60 °C.

The lack of a crystalline structure makes PDLLA more chemically reactive and more prone to biodegradation. Many solvents that do not react with the pure stereoisomers PLLA and PDLA can partially dissolve PDLLA.

As with the pure stereoisomers, molecular weight plays a vital role in determining the physical and chemical characteristics of PDLLA. The 50 to 60 °C glass transition temperature applies for polymer chains with molecular weight of up to 30,000. Keeping the polymer chains short also results in gradual decrease of this glass transition temperature. As with other polymers, this also has effects on physical properties such as tensile strength and flexibility.

Take note that these physical and chemical characteristics can still vary greatly depending on manufacturing methods. Factors such as the rate of crystallization, the molecular weight of the polymer chains, and the ratio of individual components play a significant role in determining the properties of the final polymer. Thus, these differences between PLLA, PDLA, and PDLLA are not absolute.

Applications

Even without differentiating between the different types of PLA polymers, we already know some of its more common applications. PLA is a non-toxic plastic that is considered safe for food contact.

The fact that it breaks down into non-toxic lactic acid makes it biocompatible and suitable for sutures and implants that are meant to be absorbed by the human body.

High-molecular weight PLLA is the material of choice for stents and implants that need to maintain their mechanical properties over an extended period. PLLA takes several months to degrade, and this degradation time can be further extended by producing PLLA with higher molecular weight polymer chains.

They have been used for implants meant to facilitate the reconstruction of tendons and ligaments, as well as embolic materials for arterial embolization. PLLA has better chemical stability, better withstands enzyme degradation, and has a much longer resorption time.

PDLLA, on the other hand, breaks down inside the body relatively quickly. While this makes it unsuitable for long-term implants, PDLLA is actually one of the most well-researched bioplastics today.

Its resorption behavior has been studied to a point where scientists can predict when it will degrade under normal physiological conditions. This unique characteristic has made PDLLA an ideal material for many drug-release mechanisms.

Conclusion

Most of us who are into 3D printing have probably spent a lot of time working with PLA without really knowing how complex its chemistry could be. While we may not need to know the difference between PLLA, PDLA, and PDLLA, a little extra knowledge doesn’t hurt.

If you ever find yourself in a situation where you need to 3D print medical implants or devices, it would be nice to know specifically which flavor of PLA you should use.