Fig. 7.

Illustration of enzymatic transformation of 13a to 13b upon enzymatic activity of phosphatases (e.g., ALP): (A) Molecular structures and (B) in situ biocatalytic self-assembly. Precursor 13a is converted into the self-assembling hydrogelator 13b in situ by the Saos-2 membrane-bound ALP. Upon conversion, 13b generates a cytotoxic nanonet/hydrogel “cage” surrounding the cells, while innocuous to ATDC5, which express lower membrane bound ALP. (C) Cancer cell death induced by EISA of hydrogelators: Cancer cells secrete excessive amounts of MMP-7, which converted the precursor 14 into a supramolecular gelator 15a prior to its uptake by the cells. Once inside the cells, the supramolecular gelator formed a gel via molecular self-assembly, exerting vital stress on the cancer cells. (D) Molecular structures of ER-C16, G-C16, and Leu-Ala-Arg-Lys-CONH₂ (peptide fragment). Adapted with permission from ref. ²⁹ and ³⁰. Copyright 2015, American Chemical Society.