title: Assay of ceftazidime and cefepime based on fluorescence quenching of carbon quantum dots.
abstract: A novel and sensitive method for the determination of ceftazidime and cefepime in an active pharmaceutical ingredient (API) has been developed based on the fluorescence quenching of poly(ethylene glycol) (PEG)2000-capped carbon quantum dots (CQDs) prepared using a chemical oxidation method. The quenching of fluorescence intensity is proportional to the concentration of ceftazidime and cefepime over the range of 0.33-3.30 and 0.24-2.40 µg/mL, respectively. The mode of interaction between PEG2000-capped CQDs and ceftazidime/cefepime in aqueous solutions was investigated using a fluorescence, UV/Vis and Fourier transform infrared spectrometry (FTIR) at physiological pH. UV/Vis and FTIR spectra demonstrated that ground state compounds were formed through hydrophobic interaction the fluorescence quenching of CQDs caused by ceftazidime and cefepime. The quenching constants decreased with increases in temperature, which was consistent with static quenching.
authors.affiliation: School of Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.affiliation: School of Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Zhengyu
authors.initials: Z
authors.lastname: Yan
authors.affiliation: School of Science, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Shenghua
authors.initials: S
authors.lastname: Liao
mesh_terms: D002244:Carbon / Q000737:chemistry*; D000077723:Cefepime; D002442:Ceftazidime / Q000032:analysis*; D002511:Cephalosporins / Q000032:analysis*; D005453:Fluorescence; D008968:Molecular Conformation; D011092:Polyethylene Glycols / Q000737:chemistry; D045663:Quantum Dots; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002511:Cephalosporins; D011092:Polyethylene Glycols; D002244:Carbon; D000077723:Cefepime; D002442:Ceftazidime
keywords: carbon quantum dots; cefepime; ceftazidime; fluorescence quenching; hydrogen bonding