Black Phosphorus-Based Drug Nanocarrier for Targeted and Synergetic Chemophotothermal Therapy of Acute Lymphoblastic Leukemia

As one of the novel two-dimensional nanomaterials, black phosphorus nanosheets (BP NS) have been proven to be excellent carrier materials for drugs, owing to their fine optical properties and biocompatibility. In this work, a composite drug nanocarrier based on BP NS is proposed, which can perform a synergetic and targeted chemophotothermal therapy of acute lymphoblastic leukemia (ALL). First, BP NS were prepared by an improved liquid exfoliation technique. Then, polyethylene glycol (PEG) was modified on the surfaces of BP NS through electrostatic adsorption. Drug molecules can also be loaded onto the BP NS via electrostatic adsorption. The PEG layer can effectively protect the interior BP NS from water and air to enhance their physiological stability. The obtained PEGylated BP NS (BP NS@PEG) not only demonstrated an excellent photothermal conversion efficiency and photothermal stability but also exhibited a good pH and photothermal dual-responsive drug release behavior. In addition, the BP NS@PEG were further modified with Sgc8 aptamers through covalent bonding. The aptamers provided an efficient specificity toward ALL cells (CCRF-CEM) and greatly increased the endocytosis of the nanocarriers through a receptor-mediated manner, which can further improve the therapeutic effect. Hence, the presented BP NS-based multifunctional nanocarrier can achieve a targeted and synergetic chemophotothermal therapy of ALL, which shows a promising potential in improving the curative efficiency.