Light-stimulated lowering of glucose concentration in a dextrose solution mediated by merocyanine molecules

Diabetes mellitus is a chronic metabolic disease characterized by elevated blood glucose levels and has become a global chal-lenge. Currently, the widespread and regular treatment of diabetes mellitus involves the administration of insulin. However, in-sulin is no longer considered the first choice for type 2 diabetes, and an expanding range of new treatment modalities are emerg-ing as noninsulin-based medications that are promising alternatives to regulate blood glucose levels. In this regard, controlling the glucose level in blood by external stimuli, such as light, offers a new route to governing the blood glucose concentration with the required dose and at the appropriate time. Here, we report on a light-stimulated glucose-lowering method based on spiropyran-merocyanine photoisomerization. We show that upon exposure to violet light (405 nm), the closed isoform of spiropyran molecules inside liquid crystal microspheres transforms into the open merocyanine isoform, which in turn stimulates merocyanine to translocate through the interface of the liquid crystal/dextrose emulsion. Merocyanine readily interacts with glu-cose molecules and causes a lowering of the emulsion's total glucose concentration by 20 %.