Wavelength-dependent feedback behavior in light-gated polymersome nanoreactors.

Biological systems integrate multiple feedback processes to regulate their adaptation to evolving stimuli with high specificity. Inspired by wavelength-selective feedback processes in visual signaling, we present a synthetic nanoreactor system capable of producing orthogonal, wavelength-dependent positive and negative feedback loops. Polymersomes functionalized with a broad-spectrum pyrazolone-based Donor-Acceptor Stenhouse Adduct (DASA) encapsulate an esterase enzyme and undergo light-gated permeability switching. Upon irradiation, the nanoreactors operate out-of-equilibrium, hydrolyzing ethyl acetate to generate acetic acid in a wavelength-programmed manner. Under yellow light (590 nm), positive feedback is mediated by spectral unmasking: acid-induced protonation of a solubilized dye decreases competition for yellow light, enhancing membrane permeability and enzyme activity, yielding a positive feedback loop. In contrast, blue light (405 nm) irradiation leads to the accumulation of the same dye that spectrally competes with the photoswitch, progressively suppressing membrane permeability by formation of a negative feedback loop. These stimulus-specific feedback dynamics enable reversible and tunable control over enzymatic reaction kinetics. Importantly, this platform introduces a paradigm shift for light-programmed, autonomous regulation in synthetic cell mimics and could open a pathway to dynamic modulation of microscale environments and biointerfaces without genetic intervention.