Sustainable Synthesis of N, S-Enriched Carbon Sensor from Euphorbia royleana Latex for Low-Cost Fluorescence Based Detection of Arsenic Ions.

The present work describes development of heteroatom doped carbon sensor from latex of Euphorbia royleana to produce nitrogen and sulphur rich carbon material. Alkaloids present in latex provide a natural resource for inserting these two atoms in carbon matrix. The surface morphology revealed by HR-TEM, SEM and XRD analysis demonstrated amorphous nature of material with some crystallinity. The produced material, labelled as LAC, demonstrated exceptional performance for highly sensitive UV-Vis and fluorescence spectroscopy detection of arsenic ions. It displays a significant absorption peak at 291 nm in UV-Visible spectrum and emission peak at 396 nm in fluorescent spectrum. The adsorption of arsenic ions greatly diminished these peaks. The peak intensity was used to analyse ion's concentrations from 0 to 66 nM with limit of detection (LOD) of 3.87nM. The work demonstrated that alkaloid precursors can be used as natural compounds to generate fluorescent sensors for arsenic detection without addition of external chemicals.