Development of ionic liquid-capped carbon dots derived from Tecoma stans (L.) Juss. ex Kunth: Combatting bacterial pathogens in diabetic foot ulcer pus swabs, targeting both standard and multi-drug resistant strains
Nisha Yadav, Deeksha Mudgal, Shivakant Mishra, Hitesh Sehrawat, Niraj Kumar Singh, Kalicharan Sharma, Prabodh Chander Sharma, Jay Singh, Vivek Mishra
Abstract
Bacterial infection is rapidly growing and is a severe danger to global welfare worldwide. Consequently, there is a growing demand for novel antibacterial medications. As an outcome, the evaluation of antibacterial assets of carbon dots (CDs) including a variety of ionic liquids (ILs) were employed to reside advance notice of the structure tunability of ILs along with abundant surface functional group of designed amine-modified CDs, have recently sparked a lot of interest. In this study for the first time, highly efficient ionic-liquid decorated CDs were synthesized to assess the impact of capped-ionic liquid on the degree of antibacterial activity. Fluorescent amine-modified CDs (CDs-NH 2 ) were obtained from the Tecoma stans (yellow elder flower) extract by a single-step carbonization method in presence of ethylenediamine, and then capped with ionic liquids; 3-(carboxymethyl)-1-methyl-1-H-imidazol-3-ium bromide (IL IM ) and 3-(carboxymethyl)-1-methyl-1-H-benzo[ d ]imidazole-3-ium bromide (IL BIM ) by a simple carbodiimide chemistry. In-vitro antibacterial activity of CDs-NH 2 , IL IM @CDs and IL BIM @CDs were evaluated against common pathogens, Escherichia coli ( E. coli ) as Gram(-ive) bacteria and Staphylococcus aureus ( S. aureus ) as Gram(+ive) bacteria as well as against clinical multi-drug resistant strain obtained from pus swab of diabetic foot ulcer, by microdilution method as well as well-diffusion method. The results showed that functional ILs-capped CDs have enhanced antibacterial activity against standard ( E. coli, S. aureus ) and clinical resistant bacterial strains, with minimal inhibitory concentrations (MICs) values range from 0 to 64 μ g/mL for standard E. coli/ S. aureus and 250 μ g/mL for drug resistant clinical strains, respectively. Structure activity analysis and molecular docking studies revealed that the antibacterial activity of IL BIM @CDs/IL IM @CDs is particularly better compared to CDs-NH 2 and ionic-liquids. • To explore biological activity of Tecoma stans ( L. ) Juss. ex Kunth in the form of CDs. • Green synthesis of doped CDs from Tecoma stans for enhanced antibacterial nanotherapeutics. • Ionic liquid-capped CQDs excel against Gram (+ive), Gram (-ive), and drug-resistant bacteria. • MICs values 0–64 μ g/mL for standard bacteria and 250 μ g/mL for drug resistant clinical strains.