Bright red fluorescent amphiphilic carbon dots as dualphase and visual sensor for selective detection of As3+ in aqueous environment

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2023-03, Vol.661, p.130882, Article 130882
• Main Authors: Rajendran, Sathish, Bhunia, Susanta Kumar
• Format: Article
• Language: English
• Subjects: Absorption; Hydrocoating; Liquid and solid phase senors; Red fluorescent amphiphilic C-dots; Selective detection of As3
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2022.130882

Increasing attention has been focused in the area of multi-mode sensing method for on-site application to avoid the false positive results and enhance the accuracy label measurements. This article reports the synthesis of bright red fluorescent amphiphilic carbon dots (C-dots) as dualphase fluorescent nanosensor for selective detection of As3+ in water. One-pot solvothermal approach was chosen for the C-dots synthesis with a maximum fluorescence quantum yield of 47%. Bright red fluorescence of the C-dots was selectively weakened upon the treatment with As3+, although the other competing ions showed infectivity. Static quenching was proved behind this fluorescence attenuation by absorbance and time-resolved fluorescence spectroscopy. The amphiphilicity of synthesized C-dots has been utilized to detect As3+ in both liquid and solid phase. Aqueous dispersion of C-dots showed a dramatic fluorescence quenching efficiency of maximum 80%. To fabricate solid phase sensor, C-dots were successfully coated and absorbed on silica beads and cotton buds. These fluorescent solid matrices also displayed a relative good quenching efficiency (70–80%) towards As3+ without any leaching out of the C-dots from the solid surface. In addition, these C-dots showed an adequate potentiality to detect this ion in real water sample analysis. These findings would enable a great potentiality in the environmental water contaminants sensing technology. [Display omitted]