Photosystem II submembrane fractions were immobilised by entrapment in poly(vinyl-alcohol) bearing styrylpyridinium groups (PVA-SbQ). The properties of the immobilised material, in a single-compartment micro-photoelectrochemical cell using platinum electrodes in potentiostatic mode, were compared with native (free) samples. The optimal operating conditions were investigated (electron acceptor concentration, pH, temperature, time contact and chlorophyll concentration). The photocurrent of the immobilised fractions could be inhibited by pollutants such as heavy metals (mercury, copper, lead, cadmium, chromium, nickel, and zinc) in solution. The potential for use of this system to evaluate the toxicity of sewage sludges was shown.