Organosilica sol-gels are shown to exhibit bulk volume changes when the osmolarity of the external medium is altered (see figure). These glasses stabilize enzymes in low-water-content laundry detergent formulations, and when diluted with water, the enzymes can be released on demand for potential applications in fabric care systems. Such osmotic triggering is reminiscent of osmoregulation and osmoadaption in natural biological systems.