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bioRxiv · 10.1101/2024.03.31.587464

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

Jain, S.·Sahu, N.·Bhatia, D. D.·Yadav, P. D.
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Abstract

Carbon quantum dots derived from mango leaves exhibited bright 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 the case of epithelial (RPE-1) cells. Upon in vitro testing, the bioconjugate demonstrated a mitigating effect on the individual toxicity of both DOTMA and mQDs in SUM-159A (cancerous cells) and of DOTMA in RPE-1 cells. Conversely, it exhibited a proliferative effect on RPE-1 (epithelial cells). Surface modifications of QDs with lipids thus enhances their compatibility with biological systems, reducing systemic toxicity, minimizing off-site effects, sustaining drug release, and modulating cellular viability through various mechanisms (for example, apoptosis), which is, therefore, crucial for multiple applications such as targeted therapeutics. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=150 SRC="FIGDIR/small/587464v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1eca201org.highwire.dtl.DTLVardef@7ff0a3org.highwire.dtl.DTLVardef@18f89b2org.highwire.dtl.DTLVardef@993b42_HPS_FORMAT_FIGEXP M_FIG C_FIG Red emitting, fluorescent carbon quantum dots synthesized using mango leaves(mQDs) showed enhanced cellular uptake and reduced cell viability in the case of cancer cells when compared with lipid-coated mQDs. However, in the case of non-cancerous cells, the lipid-coated mQDs showed enhanced cellular uptake and cell viability when compared with mQDs alone.

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Jain, S., Sahu, N., Bhatia, D. D., Yadav, P. D.. 2024-04-01. Cellular uptake and viability switch in the properties of lipid-coated carbon quantum dots for potential bioimaging and therapeutics. https://doi.org/10.1101/2024.03.31.587464

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