Rational Design of Molecularly Imprinted Nanozymes for Selective Degradation of Poly(bisphenol A carbonate) (BPA-PC)

Poly(bisphenol A carbonate) (BPA-PC) is an engineering thermoplastic whose recycling is hindered by its Code-7 classification and environmental BPA leaching. Here, we report water-soluble molecularly imprinted nanozymes for the selective depolymerization of BPA-PC under mild alkaline conditions. Synthesized within cross-linked surfactant micelles, the optimized nanozyme combines shape-complementary BPA-matched pockets with surface basicity, achieving a 72-fold rate enhancement over porcine pancreatic lipase. Fluorescence titrations with a soluble dansyl-labeled BPA-PC dimer confirm strong substrate recognition (K_a ~10⁶ M^-1). Gel permeation chromatography reveals uniform reductions of 52-55% across M_n, M_w, and M_z, indicative of a random endo-chain cleavage mechanism. On macroscopic BPA-PC films, the nanozyme induces pronounced cracking and surface erosion, whereas polyethylene terephthalate (PET) control films remain undamaged. Furthermore, the aqueous nanozyme retains ~75% of its initial catalytic activity across five consecutive degradation cycles following simple phase extraction. This study demonstrates that tailored, shape-complementary nanozymes provide a generalizable, selective biocatalytic alternative for the circular chemical recycling of recalcitrant engineering plastics.