Carbon quantum dot based nanocarrier labeled with anti-PDL1 antibody as a promising theranostic candidate for the triple negative breast cancer treatment

Triple-negative breast cancer is a significant health concern for women worldwide. With the development of optical and chemical methods, carbon dots (CDs), as a special class of carbon nanomaterials with unique physiochemical properties, have attracted the attention of researchers in topics such as tumor theranostics, especially bioimaging and targeted therapy. The goal of this research is to create theranostic nanoparticles (NPs)-antibody-conjugated systems that will improve cancer diagnostics and therapeutic effects. The CDs bioconjugate constituting carbon dots was prepared as an imaging agent and anti-PDL1 antibody as a targeting and immunotherapy agent. MTT test was used to evaluate the cell viability of MDA-MB-231 (breast cancer cells) exposed to anti-PD-L1-CD. The effect of anti-PD-L1-CD on proliferation and apoptosis was detected by colony assay and AO/EB assay, respectively. Our results demonstrated that CD could help to effective internalization of anti-PD-L1 antibodies into MDA-MB-231 cells and boost the cytotoxic impacts of anti-PD-L1 antibodies. Additionally, the study showed that anti-PD-L1-CD inhibited cell viability and proliferation of tumor cells more efficiently than free anti-PD-L1 antibody.