PubMed Health⌕ Search

PubMed · 10344871

Plasma surface modification in biomedical applications.

Abstract

New medical products, materials and surgical procedures keep improving current health-care practices. Many of these innovations involve polymeric devices that must meet certain clinical and cost requirements. Chief among these pressures is the need for biocompatibility between the physiological environment and the biomaterial surface. Plasma surface modification can improve biocompatibility and biofunctionality. This article reviews the capabilities and applications of the technology.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J H Loh. Plasma surface modification in biomedical applications.. https://pubmed.ncbi.nlm.nih.gov/10344871/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Effect of sphered particles on the firing contraction of porcelain inlay processed by cold isostatic pressing.

The effect of the sphered particles on the contraction ratio of porcelain inlay processed by the cold isostatic pressure (CIP) method was investigated. The conventional lathe-cut porcelain powder was crushed to finer particles and the secondary particles with spherical shape by adding binders of acrylic resin, wax, and polyvinyl alcohol, respectively. Porcelain powder was molded as a disc-shaped green body in a refractory model and compressed at 200 MPa by CIP. From this green compact, the sintered porcelain was obtained by only one step of firing. The porcelain discs were then used for the measurements of contraction ratio, scanning microscopic observation, biaxial flexure strength, Vickers hardness, and density. Firing contraction was decreased to about 1% in the sphered particle groups, compared with 7% of the lathe-cut porcelain powder. Although biaxial flexure strength was about 85 MPa, which is lower than the 120 MPa of the control group, and the density was significantly decreased by about 10% from the 2.4 g/cm3 of the control substance, Vickers hardness, which ranged from 531 to 537, showed no significant differences among all of the groups. The CIP method could save labor in the process of making porcelain inlays, and sphered powders could contribute significantly to a decrease in the contraction ratio in the sintering process.

Biocompatible Materials↗

Residual ethylene oxide in medical devices and device material.

Ethylene oxide (EO) gas is commonly used to sterilize medical devices. The amount of residual EO remaining in a device depends partly on the type and size of polymeric material. A major concern is the amount of residue that may be available in the body. With the use of the method described by AAMI for headspace analysis of EO residues, different polymers and medical devices subjected to different numbers of sterilization cycles were examined. Next, the effect of various extraction conditions and extraction solutions on these polymers and medical devices was evaluated. The results showed different polymers desorb EO differently. One polyurethane (PU 75D) had much higher EO residue than a different polyurethane (PU 80A). Repeated extraction of the PU 75D was necessary to quantify total EO residue levels. Different extraction solutions influence the amount and reproducibility of EO detected, whereas multiple resterilizations showed no difference in amount of residual EO. Bioavailability of EO was estimated by extracting the devices and polymers in water. Comparison of total EO residues to EO that was bioavailable showed no difference for some polymers and devices, while others had an almost eightfold difference. Some standard biocompatibility tests were run on extracts and devices, but no significant effects were observed.

Biocompatible Materials↗

Use of isothermal heat-conduction microcalorimetry (IHCMC) for the evaluation of synthetic biomaterials.

Isothermal heat-conduction microcalorimetry (IHCMC) allows measurement of extremely small rates of heat flow-on the order of 0.1 microwatt. This provides, for example, the ability to directly observe-and quantitate in a few days-rates of degradation as low as 1% per year at body temperature, in solid material samples of a few grams. Also, one method of IHCMC data analysis allows direct determination of the reaction-rate constant at the temperature of interest, thereby avoiding possible errors due to rate mechanism changes with temperature, an issue that needs to be considered when the Arrhenius method is used. IHCMC can also be used to measure transient phenomena, such as heat of adsorption, and initial metabolic responses of cellular entities to biomaterials. The purposes of this review article are to (a) explain the basic principles, attractive features, limitations, and methods of IHCMC; (b) describe biomaterials applications to date--including studies of the stability of ultra-high-molecular-weight polyethylene and implant-grade calcium sulfate, setting reactions of dental adhesives, and macrophage response to biomaterial particles; (c) provide a discussion of issues and concerns that should be addressed in order to maximize the utility of IHCMC in biomaterials studies; and (d) suggest a number of possible future biomaterials applications for this technique.

Biocompatible Materials↗