Simple fabrication of multifunctional hyperbranched copolymer based on L-lysine and citric acid for co-delivery of anticancer drugs to breast cancer cells

The aim of this study was to prepare a novel drug delivery system based on hyperbranched polymers having lysine as the repeating units for cancer treatment. The hyperbranched Poly (L-Lysine citramide) (HBPLC) was synthesized from citric acid and L-lysine via the polycondensation method. Then, the post-functionalizing of the desired polymer with both PEG and folic acid was carried out in order to achieve the HBPLC-PEG-FA nanocarrier. The structure and morphology of the resulted system was determined using different techniques. According to SEM studies, the particle sizes of prepared HBPLC and HBPLC-PEG-FA were about 10-15 nm and 80-150 nm, respectively. The loading capacity, in-vitro release behavior, antioxidant, and MTT characteristics of HBPLCPEG-FA were investigated. The encapsulation efficiency (EE%) values of DOX and MTX for HBPLC-PEG-FA were 96.3% and 96.9%, respectively. The antioxidant activity of the HBPLC-PEG-FA nanocarrier was 53.9%, and the kinetic and in-vitro drug release (RD) studies of nanocarrier exhibited that HBPLC-PEG-FA had controlled pH-responsive behavior (DOX: 92.7% and MTX: 97.02% at pH 5, respectively). In-vitro cytotoxicity results and degradation studies revealed that the synthesized HBPLC-PEG-FA is biocompatible and biodegradable.