A variety of methods and technical equipment are currently available for checking of air contaminants. Generally, all known and sophisticated methods are based on sampling of substances in the air using different collectors or their capture in a suitable medium. However, new detection methods particularly useful in outdoor conditions are still looking for. Detection systems must be transportable, fast acting, inexpensive, sensitive and selective, and their operation should not be complicated. Such an appropriate system for the detection of carbamates and highly toxic organophosphates is detection tubes with microcrystalline cellulose pellets containing immobilized acetylcholinesterase, by which analyzed air is sucked through. The detection is based on the colorimetric Ellman reaction. Experimental work deals with the use of pharmaceutical technology methods for preparation of new variants of pellets for the detection of acetylcholinesterase inhibitors with 20% and 50% content of inorganic fillers (aluminium oxide, kaolin, colloidal silica, nalsit) produced by extrusion / spheronization. Pellets were impregnated by acetylcholinesterase after evaluating quality parameters and were tested for their activity and inhibition with Ellmans reagent. Pellets without inorganic fillers, containing 50% of aluminium oxide and containing 20% of colloidal silica were evaluated as a suitable filling of detection tubes.