Bovine serum albumin modified carbon dots and berberine composite promotes tumor mitochondrial dysfunction and apoptosis

Precise delivery of antitumor drugs has become a research focus in cancer treatment. Herein, we developed a bovine serum albumin (BSA) modified carbon dots (CDs) and berberine (BBR) composite for improved intravenous BBR delivery. The surface-negatively charged CDs can associate with positively charged BBR through electrostatic interactions, resulting in CDs and BBR composite (BBR@CDs). BBR@CDs can be further stabilized by modification with BSA, resulting in enlarged composite (BSA@BBR@CDs) with much better water solubility. In vitro, with BSA modification, BSA@BBR@CDs was more readily taken up by tumor cells than BBR@CDs. After entering cells, BSA@BBR@CDs could more efficiently target mitochondria, resulting in mitochondrial dysfunction and eventually showing a stronger pro-apoptotic effect on tumor cells than BBR. In vivo, BSA@BBR@CDs can well accumulate in tumors via intravenous injection and significantly inhibit the tumor growth without significant toxicity to other organs. Therefore, BSA@BBR@CDs holds potential as a promising nanomedicine for cancer therapy.