Graphene Carbon Dot Assisted Sustainable Synthesis of Gold Quantum Cluster for Bio‐Friendly White Light Emitting Material and Ratiometric Sensing of Mercury (Hg²⁺)

Abstract

Herein, for the first time, we introduce a new synthetic strategy for the synthesis of stable dual light emitting gold quantum cluster‐graphene quantum dot (AuQC@GQD) nanocomposite using a single protein, gluten as the raw material. Hydrothermal treatment of wheat gluten protein resulted in the development of a stable blue‐green emitting graphene quantum dot (GQD), which was further conjugated with gluten and used for the synthesis of gold quantum clusters (AuQC). Moreover, the gluten conjugated GQD acted as a reducing agent for the fast formation of red emitting AuQC. The resulted AuQC@GQD were characterized by various spectroscopic and microscopic techniques. We further explore the use of AuQC@GQD as a probe for ratiometric detection of mercury (Hg2+). The sensor exhibited a good linear relationship in the Hg2+ concentration range from 0.1 to 35.8 ppm with a detection limit of about 0.1 ppm. Moreover, AuQC@GQD were effectively incorporated into electrospun polyvinyl alcohol (PVA) nanofibers for visual colorimetric sensing. We have monitored the visual fluorescent response of AuQC@GQD‐PVA mat to Hg2+, and the observed change of color under UV irradiation indicates the utility of the AuQC@GQD‐PVA nanofibers for on‐site detection of Hg2+. In addition, the formed AuQC@GQD can able to produces white light emission at a particular composition of HAuCl4 and GQD under UV irradiation, which can further extend its applicability in the field of optoelectronics.

Synthesis of graphene quantum dots and their applications in drug delivery

“…Hydrothermal method is a simple and rapid method for preparing GQDs [47][48][49][50]. GQDs can be finally obtained using a variety of macromolecular or small molecular substances [51] as the starting materials through high temperature and pressure [52][53][54][55]. The principle is to break the bonds between carbon materials to form GQDs via high temperature under high pressure [56][57][58][59].…”

Enhanced Photocatalytic Properties of All-Organic IDT-COOH/O–CN S-Scheme Heterojunctions Through π–π Interaction and Internal Electric Field

“…8 These radical species react with the lipid, polysaccharide, and other components of bacterial membranes, resulting in bacterial perforation and death, while also accelerating the degradation of antibiotics in water. 9,10 Thus, the photocatalytic technique can be extensively used in dental infections, 11 bacteria-infected implants, 12 and the treatment of polluted water. 13 The choice of a suitable photocatalyst is the most important factor that determines antimicrobial and degradation activity.…”

“…Photocatalytic strategy has been regarded as a feasible disinfection technology, which is facile, fast, and efficient and causes minimum environmental pollution. , This technique employs the easily available and clean solar energy irradiation to activate semiconductors, splitting water to produce a series of reactive oxygen species including superoxide radicals ( • O 2 – ), singlet oxygen ( 1 O 2 ), hydrogen peroxide (H 2 O 2 ), and hydroxyl radicals ( • OH) . These radical species react with the lipid, polysaccharide, and other components of bacterial membranes, resulting in bacterial perforation and death, while also accelerating the degradation of antibiotics in water. , Thus, the photocatalytic technique can be extensively used in dental infections, bacteria-infected implants, and the treatment of polluted water …”

Ultrastable Gold–Copper Nanoclusters on Nitrogen-Doped Graphene Quantum Dots for Selective Electrochemical and Fluorescence Sensing of Glycine

“…15 Even with thiolate as a capping agent, a most functional of smaller ligand category, which has the ability to form stable metal−sulfur covalent bonds 16 with the metals such as Au, Ag, and Cu, the CuNCs were prone to oxidation 17 which led to lower temporal stability of the NCs. Therefore, usually, larger molecules such as polymers, 18 DNA, 19 proteins, 20 and peptides 21 were used as steric capping agents for stabilizing NCs. Even though these larger molecules can comparably stabilize the NC, using larger molecules in the synthesis causes characterization difficulties and lower accessibility of NCs leading to lower performance.…”