title: Synthesis of fluorescent carbon dots via simple acid hydrolysis of bovine serum albumin and its potential as sensitive sensing probe for lead (II) ions.
abstract: Carbon dots have great potential to be utilised as an optical sensing probe due to its unique photoluminescence and less toxic properties. This work reports a simple and novel synthesis method of carbon dots via direct acid hydrolysis of bovine serum albumin protein in a one-pot approach. Optimisation of the important synthetic parameters has been performed which consists of temperature effect, acid to protein ratio and kinetics of reaction. Higher temperature has promoted better yield with shorter reaction time. The carbon dots obtained shows a strong emission at the wavelength of 400 nm with an optimum excitation of 305 nm. The potential of the carbon dots as optical sensing probe has been investigated on with different cations that are of environmental and health concern. The fluorescence of the carbon dots was significantly quenched particularly by lead (II) ions in a selective manner. Further analytical study has been performed to leverage the performance of the carbon dots for lead (II) ions sensing using the standard Stern-Volmer relationship. The sensing probe has a dynamic linear range up to 6.0 mM with a Stern-Volmer constant of 605.99 M(-1) and a limit of detection (LOD) of 5.05 μM. The probe performance was highly repeatable with a standard deviation below 3.0%. The probe suggested in this study demonstrates the potential of a more economical and greener approach that uses protein based carbon dots for sensing of heavy metal ions.
authors.affiliation: Faculty of Engineering, Computing, and Science, Swinburne University of Technology Sarawak Campus, Jalan Simpang Tiga, 93350 Kuching, Sarawak, Malaysia.
authors.forename: Shui Shui
authors.initials: SS
authors.lastname: Wee
authors.forename: Yann Huey
authors.initials: YH
authors.lastname: Ng
authors.forename: Sing Muk
authors.initials: SM
authors.lastname: Ng
mesh_terms: D000818:Animals; D002244:Carbon / Q000737:chemistry; D002413:Cations, Divalent; D002417:Cattle; D005456:Fluorescent Dyes / Q000138:chemical synthesis* / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007854:Lead / Q000302:isolation & purification*; D057230:Limit of Detection; D046529:Microscopy, Electron, Transmission; D015335:Molecular Probes / Q000138:chemical synthesis* / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry* / Q000648:ultrastructure; D015203:Reproducibility of Results; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013464:Sulfuric Acids / Q000737:chemistry; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D002413:Cations, Divalent; D005456:Fluorescent Dyes; D015335:Molecular Probes; D013464:Sulfuric Acids; D014874:Water Pollutants, Chemical; D012710:Serum Albumin, Bovine; D007854:Lead; D002244:Carbon; C033158:sulfuric acid
keywords: Bovine serum albumin; Carbon dots; Fluorescent quenching; Heavy metals; Nanoparticles; Optical sensing