The new biocompatible and anti allergic approach to detect selected human sweat ingredients as glucose, important for evaluation of human physiological and metabolical conditions was implemented by using suitable enzymes be able to transfer selected sweat substrates to optically detectable submicron products.

Today the glucose determination apparatus are widely used in common life, medicine and pharmacology. Commercially available sensors are frequently used for detection and determination of glucose concentration in macroscopic range. Our aim was to develop and assemble submicrometer polyelectrolyte microcapsule sensor that will increase the lower sensitivity for glucose and will be capable to measure glucose concentration above 200 mM with linear response. The enzyme's optimal substrate activity was studied in the polyelectrolyte LbL (Layer-by-layer) assembled microcapsules for being able to exchange analyte with outer measuring environment, i.e. human sweat. For that purpose GOX and HRP were encapsulated and immobilised in microcapsules with suitable enzyme substrate, o-dianisidine or guaiacol. The efficacy of encapsulated enzymes was determined by fluorescence spectra measurements using partially labeled enzymes with fluorescence dyes, while the glucose or lactate detection was evaluated by UV/Vis photospectroscopy for various reaction times (0 to 11 minutes) at 35 ^oC and depending on the concentration of glucose and volume of administrated samples. Diffusion of glucose and lactose from the bulk sweet solution through semipermeable polyelectrolyte microcapsule wall into inner microcapsule enzyme solution was taken into account. Small ions are distributed between inner and outer solution according to well known Donnan distribution due to their concentration and presence of big nonpermeable macroions. The variation in pH and salt concentrations in human sweet depends also on different skin glands secretion on specific parts of body.

This research has been supported by a Marie Curie Transfer of Knowledge Fellowship of the EC FP6 under the contract nr. MTKD-CT-2005-029540-POLYSURF and the Slovenian Research Agency (Grant No. Z2-9623).