Bamboo stem biomass waste-derived excitation-dependent carbon dots for nanomolar detection of fungicide dodine in real samples and their pH-sensitive bacterial interaction studies

Abstract

The present work investigates the mitigation of dodine (DD) fungicide residue, which is recognized for its adverse environmental consequences, by the use of carbon dots (CDs) prepared from bamboo stem biomass (BS-CDs). This work focuses on the synthesis of BS-CDs using the one-step hydrothermal method, which has been shown the remarkable sensing efficiency even at low concentrations. The synthesized BS-CDs were analyzed through X-ray diffraction (XRD), X-ray photoelectron (XPS), Fourier transform infrared (FTIR), Raman spectroscopy, and high-resolution transmission electron microscopic techniques (HRTEM). The BS-CDs were spherical and mono-dispersed, with an average size of 3.71 nm. By utilizing the fluorescence quenching property of BS-CDs, a detection limit of 4.3 nM for DD was successfully achieved. The non-toxic profile of BS-CDs has been confirmed by cytotoxicity studies using MTT assay. Application research mostly focuses on exploring the interaction between CDs and bacteria, hence elucidating their pH-sensitive characteristics. Real sample (fruits and vegetables) analysis was carried out to assess the viability of the detection approach, and the results showed respectable recovery rates (105 to 115 %) with a relative standard deviation (∼2 %). The findings provide a positive outlook for addressing the presence of DD residue in ecologically vulnerable regions, emphasizing the viability of using BS-CDs as an environmentally friendly remedy.