Construction of Bovine Serum Albumin/AIE-Based Quaternary Complexes for Efficient Gene Transfection.

High transfection efficiency and superior cell imaging are required for cationic polymers-based gene delivery system to afford high therapeutic effect but its high toxicity and unstable cell imaging are easily ignored. In this study, cationic amino poly(glycerol methacrylate) derivative (PGMA-EDA) is used to incorporate bovine serum albumin (BSA) and aggregation-induced emission (AIE) molecular (tetraphenylethylene derivatives, TPE) as an efficient carrier for gene transfection and intracellular imaging. The obtained polymer/pDNA-TPE/BSA (PDTB) quaternary nanoparticles (NPs) not only exhibit efficient gene transfection but also show excellent biocompatibility. After inclusion of TPE/BSA (TB) NPs, BSA promoted dissociation of the complexes upon being protonated and the lipophilic TPE-reduced endosomal membrane stability, which enhanced endosomal escape of pDNA payload, finally resulting in an excellent gene transfection. On the other hand, less positive surface charge of PDTB NPs than that of the binary PD complexes, as well as the addition of biocompatible BSA, both factors contribute to the improved cell viability. Moreover, the AIE feature of TPE compared to aggregation-caused quenching character of conventional fluorophores enables the complex with stably tracking the delivery of pDNA into cancer cells. Therefore, the newly developed PDTB complexes may be a promising candidate vector for traceable, safe, and effective gene delivery.