Polymer Nanogels with Albumin Reporting Interface Created Using RAFT Precipitation Polymerization for Disease Diagnosis and Food Testing

Abstract An interface capable of recognizing and reporting target molecules is crucial for applications such as food testing, disease diagnosis, and drug delivery systems. Among biomolecules, albumin serves as a significant target for food testing and diagnosis. In this study, polymer nanogels with a recognition/reporting interface for albumin are synthesized through reversible addition–fragmentation chain transfer (RAFT) precipitation polymerization of di(ethylene glycol) methyl ether methacrylate and N , N ’‐methylenebis(acrylamide) using a poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC) macro‐RAFT agent, followed by dansyl modification. These nanogels feature dansyl groups as albumin recognition/reporting units, supported by a PMPC base to prevent nonspecific protein binding. The adsorption capacity of the dansyl‐modified polymer nanogels for albumin is validated using quartz crystal microbalance and polyacrylamide gel electrophoresis. Additionally, the nanogels effectively adsorbed albumin from human, bovine, and porcine serum by changes in fluorescence intensity. The polymer nanogels are successfully applied for the fluorescent detection of the urinary serum albumin for the diagnosis of renal disease. Furthermore, the study successfully demonstrates the fluorescent detection of contaminated BSA in the real soy milk sample as a model case of the food testing for vegans.