Modulating the physicochemical and biological properties of carbon dots synthesised from plastic waste for effective sensing of E. coli

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2020-12, Vol.196, p.111333-111333, Article 111333
• Main Authors: Kumari, Manisha, Chaudhary, Savita
• Format: Article
• Language: English
• Subjects: Blood compatibility; Carbon dots; E. coli; Pathogen; Thrombolytic activity; Turn-off sensor
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2020.111333

[Display omitted] •Fabrication of Carbon dots for single use Plastic waste.•Devolved C-dots showed significant antioxidant and in-vitro blood activities.•Fabricated C-dots render new photoluminescence sensing activities toward E. coli.•Potential usage of fabricated C-dots in different real water samples for E. coli sensing. The reliable means for the quick recognition of pathogenic bacteria for disease prevention has acquired a considerable significance among researchers for human wellbeing. The purpose of current study is to fabricate highly photo-luminescent and biocompatible carbon dots (CQDs) from single used plastic waste such as poly bags, cups and bottles for selective sensing of E. coli. The formed small sized spherical CQDs have possessed high water solubility with excellent photo stable nature. The detailed fluorescence emission studies of CQDs have illustrated the overview of different types of surface defects and emissive states in formed particles. In addition, the specific role of prepared CQDs with bio-compatible nature has been thoroughly checked on hemolysis of red blood cells by employing in-vitro blood compatibility assay. A combination of anticoagulant and thrombolytic activity of CQDs with anti-oxidative activities from reactive oxygen species (ROS) generation were found to be responsible for the biocompatibility of formed CQDs. The effective in vitro stability toward histidine, cysteine, bovine serum albumin (BSA), human serum albumin (HSA) and saline supported the biocompatibility of formed particles as a function of different concentrations of CQDs. The optimized fluorescence properties with high surface to volume ratio of CQDs have provided a better alternative for “turn-off” fluorescence detection of E. coil in aqueous media with limit of detection down to 108 CFU/mL estimated by using standard colony-counting method. The as prepared nanosensor provided easy fabrication with fast response, high sensitivity and selectivity in real water samples which might be necessary for detecting pathogenic agents. In addition, the current work has provided the large overview in blood compatibility and anti-oxidative potential of prepared CQDs and giving useful information for preparing blood–compatible nanoparticles with enhanced bacterial discrimination ability.