Cellular uptake and viability switching in the properties of lipid coated carbon quantum dots for potential bioimaging and therapeutics

Carbon quantum dots derived from mango leaves exhibited red fluorescence. These negatively charged particles underwent coating with the positively charged lipid molecule N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA). However, the bioconjugate displayed reduced uptake compared to the standalone mQDs in cancer cells (SUM 159A), and increased uptake in case of non-cancerous (RPE-1) cells. Upon in vitro testing, the bioconjugate demonstrated a mitigating effect on the individual toxicity of both DOTMA and mQDs in SUM-159 (cancerous cells). Conversely, it exhibited a proliferative effect on RPE-1 (normal cells).