Carbon dots derived from frankincense soot for ratiometric and colorimetric detection of lead (II)

Abstract

We report a simple one-pot hydrothermal synthesis of carbon dots from frankincense soot. Carbon dots prepared from frankincense (FI-CDs) have narrow size distribution with an average size of 1.80 nm. FI-CDs emit intense blue fluorescence without additional surface functionalization or modification. A negative surface charge was observed for FI-CDs, indicating the abundance of epoxy, carboxylic acid, and hydroxyl functionalities that accounts for their stability. A theoretical investigation of the FI-CDs attached with oxygen-rich functional groups is incorporated in this study. The characteristics of FI-CDs signify arm-chair orientation, which is confirmed by comparing the indirect bandgap of FI-CDs with the bandgap obtained from Tauc plots. Also, we demonstrate that the FI-CDs are promising fluoroprobes for the ratiometric detection of Pb2+ ions (detection limit of 0.12 μM). The addition of Pb2+ to FI-CD solution quenched the fluorescence intensity, which is observable under illumination by UV light LED chips. We demonstrate a smartphone-assisted quantification of the fluorescence intensity change providing an efficient strategy for the colorimetric sensing of Pb2+ in real-life samples.

Mulberry Leaves (Morus Rubra)‐Derived Blue‐Emissive Carbon Dots Fed to Silkworms to Produce Augmented Silk Applicable for the Ratiometric Detection of Dopamine

“…[ 89 ] The quantum yield (QY) and limit of detection (LOD) were calculated as per the previous reports. [ 40,44 ]…”

“…[89] The quantum yield (QY) and limit of detection (LOD) were calculated as per the previous reports. [40,44] Feeding Method of Silkworms with MB-CDs: Silkworm was an invertebrate model with the advantages of convenience and low cost and has no ethical issues related to its usage in biomedical studies. [90] Silkworms (Bombyx mori) in the second instar were obtained from a Sericulture farm in Palakkad, Kerala, India.…”

“…The CDs are adorned by functionalities such as -NH 2 , -COOH, -OH etc., that enhance their utilities for biomedical [40,41] optoelectronic [42,43] and sensing applications. [29,44] Biomarkers, the measurable indicators of genetic conditions, have biophysical properties that enable their quantification in biological samples. Abnormal concentrations of biomarkers such as dopamine (DA) in biological fluids can detect the advent of several diseases, such as schizophrenia, Parkinson's disease, and anorexia.…”

Facile Synthesis of Multifunctional Carbon Dots Derived from Camel Milk for Mn7+ Sensing and Antiamyloid and Anticancer Activities

“…Owing to its unique photoluminescence (PL) properties, CDs have attained remarkable attention for a wide range of biomedical applications . Moreover, they also possess excellent physical and chemical properties, including good aqueous solubility, flexibility for functionalization, inertness, biocompatibility, optical stability, and low toxicity. − Fluorescent CDs have been employed in various applications such as photocatalysis, cellular imaging, diagnostics, therapeutics, sensors and biosensors, and as a selective probe for detecting organic and inorganic molecules. − In particular, for sensing applications, CDs have been reported to be very sensitive and selective for the detection of metal ions, which play an important role in the environmental pollution and regulation of certain activities in biological systems. − …”

“… 21 − 24 In particular, for sensing applications, CDs have been reported to be very sensitive and selective for the detection of metal ions, which play an important role in the environmental pollution and regulation of certain activities in biological systems. 25 − 28 …”