NOVELTY - A porous film (F1) comprises crosslinked electrospun hydrogel fibers, where microbes are encapsulated within the crosslinked electrospun hydrogel fibers and the crosslinked electrospun hydrogel fibers are water insoluble and permeable and contain viable microbes encapsulated.    USE - As biosensor; for removing pollutants from an aqueous environment; and as electrode materials in bio-film reactors (claimed), biofuel cells, microbial fuel cells, fermentation reactors and waste water treatment. Also useful for making medical applicable articles (e.g. scaffolds or patches) for implanting into the intestinal tracts of patients; and for cleaning contaminated sites such as waterways, soils, sludges, waste streams, chemical spills, leaking underground storage gasoline tanks, and toxic industrial effluents.    ADVANTAGE - The film has an open pore structure; has a thickness of 1 micron to 10 cm (preferably 10-5000 microns); and has very large surface area to volume ratios, high permeability and small pore size.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for following:    (1) method (M1) of encapsulating microbes within crosslinked electrospun hydrogel fibers involving providing a mixture of microbes and a polymer, where the polymer is water soluble, is crosslinkable, and is capable of forming a hydrogel upon is crosslinked, electrospinning the polymer to form electrospun fibers, where microbes are encapsulated within the electrospun fibers, and crosslinking the electrospun fibers to form crosslinked electrospun hydrogel fibers;    (2) method (M2) of crosslinking electrospun fibers in which microbes are encapsulated involving crosslinking in a liquid polyol, where after crosslinking, the electrospun fibers form crosslinked electrospun hydrogel fibers that are insoluble and permeable, and where viable microbes are encapsulated within the crosslinked electrospun hydrogel fibers;    (3) method (M3) for removing pollutants from an aqueous environment involving contacting the pollutants with the film (F1), where microbes are encapsulated within the crosslinked electrospun hydrogel fibers, and are viable and capable of bioremediation;    (4) a biosensor (B1) comprising microbes encapsulated within crosslinked electrospun hydrogel fibers, where the microbes are viable and capable of generating a signal in response to a chemical compound;    (5) method (M4) of regenerating healthy bioflora involving implanting into the gastrointestinal tract of patients the film (F1), where the microbes are viable and capable of regenerating healthy bioflora in the gastrointestinal tract of patients; and    (6) an electrode comprising crosslinked electrospun hydrogel fibers, where the encapsulated microbes are viable and are capable of electron generation or utilization.