Research
Acceleration of research and discovery in the biological science areas rely on advancing technologies in cellular and bio-molecular isolation and analysis. Products and platforms such as immunoassays, cell culture media, filtration and analyte delivery devices require plasma surface modification to enable selective bio-molecular immobilization and to avoid surface effects due to miniaturization. Newly developed micro-fluidic platforms used throughout multiple industries including the life science fields of drug discovery, diagnostics, medical device and drug delivery are significantly enhanced with plasma treatment. Micro-channels on clinical diagnostic devices are made wettable to fluids improving both flow and dispensing.
Biochemical Assays
Improve cell adhesion to lab culture wear and bio assays
Platforms for cell culture plates and cellular matrices are predominantly fabricated from synthetic polymers. While such materials are ideally inert, mechanically stable, and low cost for this industry, their surface properties have inherent limitations. Specifically, they have inadequate binding sites for cells to anchor effectively to their surfaces. Strong, and uniformly dispersed binding sites are an important prerequisite for the immobilization of cells, and for in vitro cell cultivation. For synthetic polymer platforms to improve cellular adsorption, survivability and proliferation, they must be surface modified.
PVA TePla America have applied their expertise in gas plasma technology to solving adhesion problems of cells to culture plates. Additionally, specific plasma processes have been developed for the selective adhesion promotion of bio active molecules. This is achieved by providing specific chemical functionality at the surface, allowing coupling of cellular species to occur.
Mold release agents, volatile hydrocarbons and other contaminating species are cleaned from the substrates by the cool, yet energetic environment of the plasma. Oxidizing plasmas are used to add oxygen groups to surface. This increases polarity and renders them hydrophilic (or wettable). Hydrophilic surfaces are attractive to cells and biomolecules, inducing them to adsorb. They also eliminate the possibility of bubble formation in the reservoirs upon dispensation.
Surface modification of cell culture media for low binding affinity
Culture media designed to maintain cell suspensions require surfaces with very low affinity for cell attachment. Hydrogel coatings are uncharged, hydrophilic and have excellent adsorption resistance to proteins and cells. These coatings need to be covalently bound to the substrate surface to ensure their stability in aqueous media. Plasma surface treatment can be used either to activate the surface for hydrogel attachment, or to deposit hydrogel-like materials onto the surface using Plasma Enhance Chemical Vapor deposition (PECVD).
Plasma surface modification of DNA and Protein Microarrays
Microarray technology has accelerated the rate of biomolecular research by enabling an enormous number of experiments to be conducted in parallel. This is achieved by immobilizing arrays of probe biomolecules, such as oligonucleotides or proteins, in picomole quantities onto a substrate. The attachment of these probes requires chemically functionalizing the surface. This is a critical step in microarray fabrication and plays a significant role in their functional performance. Plasma surface functionalization reduces the complexity of wet chemical treatments, controlling surface cleanliness, functional chemistry and hydrophobicity in a single, automated process step.
Laboratory wear
Minimize non volatile leachables from plastic containers
Materials used for laboratory containers (test tubes, vials, flasks, etc.) need to be chemically inert, shatter proof, non leachable, and most often require optical clarity. Glassware fulfills most of these criteria but can easily shatter from physical or thermal shock. Plastic containers will not shatter but are susceptible to leachables such as plasticizers, stabilizers, polymerization residues etc. To achieve the best of both worlds PVA TePla America have developed a method to coat the insides of plastic containers with a quartz-like material that acts as a barrier to leachables. Flexible quartz-like coatings can be polymerized onto plastics by plasma enhanced chemical vapor deposition (PECVD). The resulting coating is a very thin (~0.5mm), highly conformal, non-crystalline and highly flexible (180o ASTM D522) coating. Markets for this barrier coating include; drug discovery, drug delivery, biological storage, stem cell and IVF culture wear. In addition to the barrier properties of this coating, SiO2 is also chemically resistant to solvents making it ideal for use in the analytical wear.
Improve reagent retrieval efficiencies
Reagent troughs are designed to maximize reagent recovery. Their shape, V or conical troughs, funnels residual reagent into more confined volumes where they can be readily retrieved. This is particularly important when using expensive reagents. Polypropylene is an ideal material for reagent troughs as it is inert, low cost and easily molded. However, polypropylene is also inherently hydrophobic. Hydrophobic surfaces make reagents form droplets on the side wall surfaces of the troughs reducing their recovery. Plasma surface modification makes polypropylene hydrophilic, eliminating droplet formation and maximizing reagent recovery.