Surface Passivation of Carbon Dots for Tunable Biological Performance

Abstract Recent investigations were shifted this trend toward exploring the biomedical applicability of CDs, relevant to chronic diseases. Herein, a systematic approach is demonstrated for studying tuning of optical character and biological performance for different surface passivated CDs. Alginate and pectin were successfully clustered oxygen-surface passivated CDs, while, chitin was used to nucleate nitrogen-surface passivated CDs. Pectin-treated with base (4.1 ± 1.8 nm) and chitin-treated acid (3.5 ± 1.7 nm) were ingrained the smallest O-surface passivated CDs and N-surface passivated CDs, respectively. However, N-surface passivated CDs were shown with the highest optical activity. CDs colloids prepared from alginate, pectin & chitin, resulted in reduction of tumor cell viability percentage to be 80.8%, 74.0% & 69.0% respectively. O-surface passivated CDs nucleated from alginate showed the highest anti-proliferative effects. Moreover, O-surface passivated CDs (from alginate) showed the supremacy in inhibition of inflammation, while, increasing of its concentration ten times resulted in significant increment in inhibition percent to be 28% & 42%, using 1 μg/mL & 10 μg/mL, respectively. So, O-surface passivated CDs (from alginate) can be applied as concurrent anti-inflammatory/antitumor drug, so as a potential therapeutic for treatment of inflammation, in production of vaccines, immune-therapeutics, and immune-suppressive drugs.