title: Fluorophotometric determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants with carbon dots via Stokes shift.
abstract: A new and facile method for the determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants is proposed in this article. Carbon dots exhibited substantial fluorescence and therefore enhanced the sensitivity of this evaluation. Understanding the formation of surfactant micelles is vital for the applications of biomedicine such as drug fabrication and smart molecular vehicles in delivering therapeutic dosage to various molecular sites. The fluorescence property of carbon dots was utilized for the first time to estimate the critical micelle concentration of surfactants. The central concept of the approach is based on the Stokes shift determination of a system composed of constant amount of carbon dots with varying concentrations of ionic and non-ionic surfactants. The synthesized carbon dots were characterized by FTIR, TEM, XRD, Raman, UV, and fluorescence spectroscope. The carbon dots were excited at 280 nm so as to obtain maximum emission for the Stokes shift measurement. The CMC value of cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), Triton X-100, dodecyldimethyl(3-sulfopropyl)ammonium hydroxide (SB-12) evaluated by this approach was found to be 0.98, 7.3, 0.19, and 3.5mM, respectively. The signals of spectra were assigned and explained in terms of both electron transitions between specific molecular orbital and the interaction with solvent.
authors.affiliation: Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, 70, Lien-Hai Road, Kaohsiung 80424, Taiwan.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Lavkush Bhaisare
authors.affiliation: Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, 70, Lien-Hai Road, Kaohsiung 80424, Taiwan; Center for Nanosciences and Nanotechnology, National Sun Yat-Sen University, 70, Lien-Hai Road, Kaohsiung 80424, Taiwan.
authors.forename: Sunil
authors.initials: S
authors.lastname: Pandey
authors.affiliation: Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung 80424, Taiwan.
authors.forename: M
authors.initials: M
authors.lastname: Shahnawaz Khan
authors.affiliation: Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung 80424, Taiwan.
authors.forename: Abou
authors.initials: A
authors.lastname: Talib
authors.affiliation: Department of Chemistry, National Sun Yat-Sen University, Kaohsiung, 70, Lien-Hai Road, Kaohsiung 80424, Taiwan; School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan; Institute of Medical Science and Technology, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University and Academia Sinica, Kaohsiung 80424, Taiwan; Center for Nanosciences and Nanotechnology, National Sun Yat-Sen University, 70, Lien-Hai Road, Kaohsiung 80424, Taiwan. Electronic address: hwu@faculty.nsysu.edu.tw.
authors.forename: Hui-Fen
authors.initials: HF
authors.lastname: Wu
mesh_terms: D002244:Carbon / Q000737:chemistry*; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D008823:Micelles; D017830:Octoxynol / Q000737:chemistry; D045663:Quantum Dots / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012997:Solvents; D013050:Spectrometry, Fluorescence; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D002593:Cetrimonium Compounds; D008823:Micelles; D000644:Quaternary Ammonium Compounds; D012997:Solvents; D013501:Surface-Active Agents; C034730:zwittergent 3-12; D012967:Sodium Dodecyl Sulfate; D002244:Carbon; D017830:Octoxynol; D000077286:Cetrimonium
keywords: Carbon dots; Cetyltrimethyl ammonium bromide; Critical micelle concentration; Dodecyldimethyl (3-sulfopropyl)ammonium hydroxide; Fluorescence spectroscopy; Sodium dodecyl sulfate; Stokes shift; Surfactants; Triton X-100