title: Resonance Rayleigh scattering spectra of tetracycline antibiotic-Cu(II)-titan yellow systems and their applications in analytical chemistry.
abstract: Tetracycline antibiotics (TCs) such as doxycycline (DOTC), chlortetracycline (CTC), oxytetracycline (OTC), and tetracycline (TC) react with Cu(II) in pH 3.5 BR buffer medium to form 1:1 cationic chelates, which further react with titan yellow to form 2:1 ion association complexes. These result in great enhancement of resonance Rayleigh scattering (RRS) and the appearance of new RRS spectra. The ion association complexes of DOTC, CTC, OTC, and TC have similar spectral characteristics and their maximum RRS wavelengths are all located at 464 nm. The quantitative determination ranges and the detection limits (3sigma) of the four TCs are 0.037-4.8 microg mL(-1) and 11.2 ng mL(-1) for DOTC, 0.041-5.2 microg mL(-1) and 12.4 ng mL(-1) for CTC, 0.050-4.8 microg mL(-1) and 15.1 ng mL(-1) for TC, and 0.088-5.0 microg mL(-1) and 26.3 ng mL(-1) for OTC, respectively. The optimum reaction conditions, the effects of foreign substances, the structure of ternary complexes, and the reaction mechanism are discussed. A sensitive, rapid, and simple RRS method for the determination of DOTC has been developed.
authors.affiliation: School of Chemistry and Chemical Engineering, Southwest University, 400715 Chongqing, People's Republic of China.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Wei
authors.forename: Zhongfang
authors.initials: Z
authors.lastname: Liu
authors.forename: Shaopu
authors.initials: S
authors.lastname: Liu
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000379:methods*; D003300:Copper / Q000737:chemistry; D004318:Doxycycline / Q000032:analysis; D009942:Organometallic Compounds; D013059:Spectrum Analysis, Raman / Q000379:methods*; D013754:Tetracyclines / Q000032:analysis* / Q000737:chemistry; D014226:Triazenes / Q000737:chemistry
chemical_list: D009942:Organometallic Compounds; D013754:Tetracyclines; D014226:Triazenes; C044584:titan yellow; D003300:Copper; D004318:Doxycycline