A method for producing bacteriorhodopsin-containing microcapsules is described, which can be optically activated, having a diameter of less than 50 μm, preferably less than 10 μm, comprising an enveloping layer, which protects the bacteriorhodopsin from harmful environmental factors, while at the same time preserving the functionality thereof. In doing so, bacteriorhodopsin is suspended in a first step in the form of PM/BR patches in an aqueous medium having a pH value ranging from 6-9 in the presence of a water-retaining polymer, and said suspension is spray-dried to form a powder, or is dried in an aliphatic solvent using low steam pressure and subsequent dehydration to form a powder. In a second step, the powder obtained in this way is provided with an envelope, which is substantially completely translucent to light in the visible range and made of a polymer and/or a paraffin having a solidification point ranging between 45°C and 65°C and/or a carnauba wax having a melting range of 70-90°C. Furthermore, such microcapsules are described, and uses of such microcapsules.
