Technical Papers Plastics
Polymers help reverse effects of acute kidney injury, facilitate wound healing and spinal surgeries

Polymers help reverse effects of acute kidney injury, facilitate wound healing and spinal surgeries

Acute kidney injury, earlier known as acute renal failure, affects about 3 in 1000 people. However, on hospital wards the situation is much more serious: up to 40% of hospital patients may suffer from this disease. With early diagnosis the effects of acute kidney injury are reversible. The clear symptoms of the disease such as fatigue, vomiting or altered consciousness, however, only appear at an advanced stage of its development when possible complications become a serious threat to life (in the most advanced stage, the mortality rate reaches up to 50%!). Kidney damage, which occurs in the late stages of the disease, may be permanent and require continued dialysis or even entire organ transplantation.

Fortunately, now it will be possible to detect the disease in its initial stages, when treatment is still relatively simple and the prognosis good. The key to this health and life-saving manner of diagnosis is a new polymer, designed at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. The chemical heart of low-cost diagnostic tools capable of detecting the early stages of kidney disease may, in the near future, be a special polymer prepared by PhD student Zofia Iskierko under the supervision of Dr. Krzysztof Noworyta, in Prof. The polymer was designed and carefully constructed so as to particularly effectively entrap only one substance in its vicinity: lipocalin-2 (NGAL), a protein naturally occurring in human blood. For the clinician, an increase in the concentration of this compound in a patient is a valuable signal of still symptomless, but already developing, acute kidney injury. Work on the implementation of the polymer, funded by grant from the Polish National Centre for Science, was carried out in collaboration with the University of North Texas in Denton, the Warsaw Institute of Physics of the Academy of Sciences and the International Institute of Molecular and Cell Biology.

"We deal with the creation of polymer recognition films for chemosensors that detect various substances. These include biomarkers and other biologically important compounds, whose presence or changes in concentration in body fluids carry information about the health of the patient. Our latest polymer can selectively capture lipocalin-2, a protein biomarker for acute kidney injury," says Dr. Noworyta. "Before acute kidney injury develops, the concentration of lipocalin increases in patient's blood. So, we devised a polymer in whose structure there are molecular cavities that are a good fit for the shape and properties of the molecules of just this compound. The probability that any other protein will get caught in them is very, very small," explains PhD student Zofia Iskierko, the lead author of the publication in the journal ACS Applied Materials & Interfaces. The new polymer was prepared by molecular imprinting. Molecules of lipocalin were first surrounded by appropriately selected (so called functional) monomers binding with the protein at specific locations characteristic only for itself. Then, a cross-linking monomer was introduced which combined with the functional one. Those monomers were later subjected to polymerization, after which the lipocalin was washed out of the resulting structure. Finally, a stable polymer film was obtained with molecular cavities matching lipocalin molecules both in terms of their local chemical features as well as their size and shape. However, it seems reasonable to suppose that in the next decade devices detecting various biomarkers and warning early on of a threat to health will become an integral part of the ubiquitous smartphone. Diagnosis would then become as simple as testing blood sugar using today's glucose meters: it would suffice to connect a removable, simple chemosensor with an appropriately selected polymer recognition film to the smartphone, apply a little physiological fluid to it and... wait for the smartphone to display the result. Everyone would be able to carry out advanced medical diagnostics as often as they deemed appropriate.

An electroactive device fabricated from polyvinylidene fluoride that facilitates wound healing has been devised by NASA. This is a device that uses electrical activity to facilitate the wound healing process while protecting the wound. The bandage is made of an electroactive material that is stimulated by the heat of the body and the pressure of cell growth, thus no external power source is required. It offers benefits of speeding the wound healing process, combining active healing and wound protection into one, offering a slim, self-contained alternative to electrical stimulation devices for accelerated wound healing and minimizing infection and related complications (e.g., illness, amputation).

The electroactive device is applied to an external wound site. This method utilizes generated low level electrical stimulation to promote the wound healing process while simultaneously protecting it from infection. The material is fabricated from polyvinylidene fluoride (PVDF), a thermoplastic fluoropolymer that is highly piezoelectric when poled. The fabrication method of the electroactive material is based on a previous Langley invention of an apparatus that is used to electrospin highly aligned polymer fiber material. A description of the fabrication method can be found in the technology opportunity announcement titled "NASA Langley's Highly Electrospun Fibers and Mats," which is available on NASA Langley's Technology Gateway.

Applications include Military personnel wounded in the field, Hospital patients who have undergone surgery, General patients who have suffered a serious wound, Astronauts in space.

Solvay's medical grade KetaSpire® polyetheretherketone (PEEK) and AvaSpire® polyaryletherketone (PAEK) polymers enabled one of the medical device pioneers, Shanghai Reach Medical Instrument Company, to develop a lighter, more ergonomic and highly cost-effective kit of reusable instruments for spinal surgeries.  Typically, these parts would be made from stainless steel. But Shanghai Reach,s goal was to reduce instrument weight by up to 70% for improved ergonomics, yet not compromise on mechanical properties or sterilizability. In addition to lightweight strength and stiffness, Solvay’s two biocompatible polymers offer strong resistance to fatigue and are compatible with sterilization methods based on stringent chemicals, steam and even gamma radiation.

The kit includes six reusable instruments: one rod bender, two pairs of distraction and compression pliers, and three awls. For the rod bender, the medical device-maker specified KetaSpire KT-880 CF 30 PEEK, a 30% carbon fiber-reinforced resin that delivers the high strength and stiffness necessary to bend implantable 5.5mm to 6.0mm titanium rods. For the pliers and awls, AvaSpire AV 651 GF 50 PAEK, a 50% glass fiber-reinforced resin offers a cost-effective balance of strength, stiffness and dimensional stability.

  Back to Articles

Previous Article

Next Article

{{comment.Name}} made a post.




There are no comments to display. Be the first one to comment!


Name Required.


Email Id Required.

Email Id Not Valid.


Mobile Required.

Email ID and Mobile Number are kept private and will not be shown publicly.

Message Required.

Click to Change image  Refresh Captcha



Reclamax single step plastic recycling machine

Reclamax single step plastic recycling machine