Abstract: An enzyme reactor system is provided based on the entrapment of a coenzyme-requiring enzyme, a coenzyme, and a regeneration enzyme in a hydrogel layer coated on a support, and confined by an ultraporous thin film semipermeable membrane. The diffusion barrier confines the coenzyme-requiring enzyme, coenzyme, and regeneration enzyme but lets substrate and reaction products, exclusive of coenzyme, diffuse freely into and out of the hydrogel layer. In an alternate embodiment, the support is formed of an ultraporous thin film semipermeable membrane on a microporous or macroporous support, through which the reaction products, exclusive of coenzyme, can diffuse freely, but through which neither coenzyme-requiring enzyme, coenzyme, regeneration enzyme, nor substrate can pass. In this embodiment, the product is recovered in high purity, free of substrate, coenzyme-requiring enzyme, coenzyme, and regeneration enzyme.

Abstract: An enzyme reactor system is provided based on the entrapment of an enzyme in a hydrogel layer coated on a support, and confined by an ultraporous thin film membrane diffusion barrier. The diffusion barrier confines the enzyme, but lets substrate and reaction products diffuse feeely into and out of the hydrogel layer. In an alternate embodiment, the support is formed of an ultraporous thin film membrane diffusion barrier on a microporous or macroporous support, through which the reaction products can diffuse freely, but through which neither enzyme nor substrate can pass. In this embodiment, the product is recovered in high purity, free of substrate and enzyme.

Abstract: A bioreactor is disclosed in which cells are confined to a compartment formed by porous hydrophyllic sheet membranes through which a nutrient solution diffuses in and exocellular products and metabolic waste diffuse out. Adjacent gas compartments allow the flow of free oxygen into the cell compartment. Each cell compartment is configured to place cells within about 100-200 micrometers of the oxygen transport membrane.

Abstract: Adherent, PTFE coatings on polymer surfaces can be produced at temperatures well below the sintering temperature of PTFE, by contacting the surface with a dilute dispersion of PTFE particles and heating the surface to its softening point (in the vicinity of its glass transition temperature) to dry it and to cause the individual particles to become embedded in and surrounded by the polymer.

Abstract: In applications involving interleaving membranes with separators, for bioreactors, dialyzers, and membrane filters and the like, shrinkage of the separator, preferably made of polypropylene, polyamides, or polyethylene terephthlate fiber web, is avoided, and the need for the use of exotic and expensive fluorinated hydrocarbon polymer materials for such separators is avoided by subjecting the separator to untensioned heating at temperatures of from about b 120 l degrees C., up to a temperature less than the glass transition or melting temperature of the polymer web under wet steam at a pressure of from about 1.0 to about 2.0 atmospheres for a time of at least about 20 minutes.

Abstract: A fabric of a polymer material useful for filtration and other purposes can be treated with a mixture of a solvent for the polymer material in a liquid which is not a solvent for the polymer material and which is more volatile than the solvent for a time and at a temperature sufficient to dissolve some polymer material in the strands. As this occurs the surface tension of the dissolved polymer will cause the dissolved polymer to move to create a continuous, smooth walled, curved surface connecting adjacent strands and extending between such strands.