# Heteroatom-doped carbon dots from medicinal plants as novel biomaterials for as-use biomedical applications in comparison with synthetic drug, zaltoprofen

## TL;DR

Carbon dots made from medicinal plants were compared to drug-derived carbon dots for biomedical uses, showing good membrane protection and antibacterial effects.

## Contribution

FN-doped carbon dots from medicinal plants are proposed as novel biomaterials with potential biomedical applications.

## Key findings

- FN-CDs showed 55.3% membrane protection compared to 80.4% for Z-FN-CDs.
- FN-CDs exhibited higher DPPH-free radical scavenging activity (69.4%) than Z-FN-CDs (54.2%).
- FN-CDs displayed a ZOI of 9–19 mm against bacterial strains.

## Abstract

FN-doped carbon dots were synthesized using powdered leaves of Moringa oleifera L./Chromolaena odorata L./Tridax procumbens L./Tinospora cordifolia L./ and Lantana camara L., along with a precursor called 4,5-difluoro-1,2-benzenediamine (DFBD) and compared against the drug zaltoprofen derived carbon dots. They were assessed for their optical and structural characteristics using photoluminescence (optimal emission λ of 600 nm), vibrational (FTIR) spectroscopy (characteristic wave numbers of 1156 and 1269 cm−1 for C–F), as well as X-ray diffraction (XRD) (highest intensity at 27.56°) and high-resolution transmission electron microscopy (HR-TEM) (particles in the size range of 15–20 nm). Further, field emission scanning electron microscopy (FESEM) / energy dispersive spectroscopy (EDX) indicated FN doping of oval/oblong carbon dots. Membrane protection in percent is found to be 55.3 and 80.4 for FN-CDs and Z-FN-CDs respectively. The DPPH-free radical scavenging activity by FN-CDs was 69.4%, while with Z-FN-CDs, it was 54.2%. When tested on six bacterial strains (three each for gram-positive and gram-negative), the FN-CDs displayed a halo (ZOI) between 9 and 19 mm, whereas the Z-FN-CDs displayed a clearance zone between 9 and 17 mm. The FN-CDs showed significant emission-red-shift effects and demonstrated concentration-dependent biocompatibility and viability in neuroblastoma and beta-TC6-cell lines.