Plastics In Medical &
Healthcare Sector Emerging Trends & Applications
PEEK Polymer for Spinal Implant Device
PEEK is an attractive alternative to titanium for spinal
implants because it shares similar modulus to bone, and
its radio transparency allows for easy visualization in
X-rays, said Solvay in a press release. The polymer is
also inert, which means it does not interact with human
tissue. While this quality supports biocompatibility, it
means that PEEK does not naturally lend itself to bone
growth. DiFusion solved this problem by compounding
negatively charged zeolites into Solvay’s Zeniva PEEK
polymer.
Kink-Resistant Tubing In smaller medical devices
Today’s implantable medical devices require bio-friendly
silicone that keeps fluids flowing even when space is
tight.
Combining highly biocompatible silicone with the
elasticity and durability of nylon creates a class of
durable, crush- and kinkresistant tubing that’s ideal for
today’s small yet highly complex medical devices.
That’s because small is the name of the game when it comes
to today’s implantable medical devices, and tubing has to
shrink to fit them. The challenge is that silicone – the
most biocompatible, durable and flexible material for
tubing – tends to kink when produced in small sizes.
The solution is reinforced tubing, which allows
significant reduction of the bend radius of small silicone
tubes. This opens up design possibilities for long-term
implantable devices, drainage tubes and tubes that resist
collapse under higher vacuum pressures.
Bioresorbable Polymers
Some of the typical applications for bioabsorable polymers
include sutures, rods, plates, screws, and scaffolds for
tissue engineering.
What are bioresorbable polymers?
Bioresorbable polymers are materials that are absorbed in
the body after performing the desired therapeutic
function. Implants produced with bioresorbable polymers
are decomposed in the body by natural degradation pathways
into water and carbon dioxide. There are two kinds of
bioresorbable materials, biopolymers which are naturally
derived and biopolyesters which are synthetically
produced. Biopolyesters include for example polylactide (PLA)
poly lactide-co-D, L lactide (PLDL,) poly
lactideco-glycolide (PLGA,) poly lactide-co-caprolactone (PLCL,)
poly caprolactone (PCL) poly dioxanone (PDO,) and poly
lactide-cotrimethylene carbonate (PL-TMC). These
biopolyesters are available as either amorphous or
semi-crystalline polymers which provide a range in
mechanical strength and degradation profile. Bioresorbable
polymers provide the possibility to customize the level of
crystallinity, hydrophilicity, molecular weight, and
degradation profile of the polymers to further improve
mechanical properties and biocompatibility.
Medical Device Adhesives
Medical devices require careful consideration when
choosing adhesives. From design of the base part to the
application method to the final intended use, many factors
can affect the success of an adhesive joint. Prudent and
conscious design choices are key factors in determining
the success of any medical product.
Adhesives can offer many merits over designing with
fasteners. They can provide cost reduction in many cases,
and offer another choice to increase flexibility in
design. They can be pre-tested by vendors to confirm their
compliance with ISO 10993 or USP I to VI and be used to
bond and seal between parts. These factors can assist in
passing biocompatibility testing of the completed device.
Overall, their applications are broad and their use in the
medical field will only grow as both device variety and
adhesive technologies advance in the years to come.
From silicones and epoxies to acrylic-based adhesives, the
world of medical adhesives is broad in its choices and
applications. As novel medical treatments and technologies
have come forth, medical adhesives have flourished,
integrating themselves into the designs of many medical
devices. Components with materials that once provided
difficulty-catheters, disposables, other compliant
materials—are now reliably bonded in production lines with
predictable and controlled medical adhesives.
Applications
Adhesives can be categorized into the following segments :
• Structural: adhesives with defined load bearing
properties, typically chemically curing, resulting in high
strength bonds for the most demanding applications.
• Non-structural: adhesives for uses other than load
bearing, typically physically curing (solvent/water
evaporation, hot melt), for light-duty or cosmetic
applications.
Pressure Sensitive: adhesives generally for temporary
applications, cured through the application of pressure
between two surfaces, primary application—skin-based.
Medical Swabs
Swabs are one of the most commonly used single-use devices
in the medical industry.
Polyester Tipped Swabs
Polyester is a synthetic spun fiber made from a polymer.
Originally introduced into the realm of medical
diagnostics by DuPont under the brand name Dacron®, it is
now manufactured by others and no longer carries a brand
name. Polyester fiber has been tested and validated for
use in specimen collection in microbiology, rapid test
diagnostics and PCR analysis.
Polyester tipped swabs boast excellent collection and
release properties and, while somewhat more costly than
cotton or rayon, are not absorbent and boast superior
release properties. Puritan purchases only the finest
grade spun polyester fibers which are then produced to our
specification of finish and other characteristics to
assure reliable performance, every time.
Foam Tipped Swabs
Medical grade polyurethane foam has been found to be an
excellent tip material for diagnostics. Foam is produced
in a range of porosities in sheet form. Common
configuration for use in tipped applicators is 100 ppi
(pores per inch).
Puritan specifies thickness, width and porosity of the
material purchased from a U.S. manufacturer for
incorporation in medical devices. Other properties are
specified as well, such as absorbency (hydrophilic being
very absorbent and hydrophobic being not absorbent), open
or closed cell, conductive or electrostatic dissipative,
even colored. For chemical resistance, polyethylene foam
is chosen. Your intended use dictates which foam tipped
swabs will work best.
Hydrogel Coating produces more comfortable, enhanced
medical elastomers
Catheters, intravenous lines and other types of surgical
tubing are a medical necessity for managing a wide range
of diseases. But a patient’s experience with such devices
is rarely a comfortable one.
Now engineers at Massachusetts Institute of Technology
(MIT) have designed a gel-like material that can be coated
onto standard plastic or rubber devices, providing a
softer, more slippery exterior that can significantly ease
a patient’s discomfort. The coating can even be tailored
to monitor and treat signs of infection.
The hydrogel coating can be embedded with compounds to
sense, for example, inflammatory molecules. Drugs can also
be incorporated into and slowly released from the hydrogel
coating, to treat inflammation in the body.
References :
https://www.medicalplasticsnews.com/news/opinion/friend-ofthe-earth/
https://www.med-technews.com/news/cleaning-up-fillers-andcoatings-offer-slow-release-antiseptic/
https://www.medicalplasticsnews.com/news/its-a-small-worldthe-move-from-silicone-to-micro-moulding/
https://www.medicaldesignbriefs.com/component/content/article/1106-mdb/tech-briefs/27841-low-density-polymerlightens-the-load-of-prosthetic-hand
https://www.plasticstoday.com/medical/solvay-s-peekpolymer-gets-nod-spinal-implant-device/181484498757812
http://www.medicaldesignandoutsourcing.com/make-kinkresistant-tubing-work-smaller-medical-devices/
https://www.medicalplasticsnews.com/news/opinion/disappearing-world/
https://www.mpo-mag.com/contents/view_online-exclusives/2017-11-02/medical-device-adhesives-specifications-andfailure-modes/
https://blog.puritanmedproducts.com/medical-swabs-how-tochoose
https://www.materialstoday.com/polymers-soft-materials/news/hydrogel-coating-enhanced-medical-elastomers/
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