Key Laboratory of Luminescent and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, China.
Luminescence. 2015 Mar;30(2):207-15. doi: 10.1002/bio.2714. Epub 2014 Jun 27.
A new method based on resonance Rayleigh scattering (RRS) was proposed for the determination of quinolones (QNS) at the nanogram level. In pH 3.3-4.4 Britton-Robinson buffer medium, quinolones such as ciprofloxacin, pipemidic acid (PIP), lomefloxacin (LOM), norfloxacin (NOR) and sarafloxacin (SAR) were protonated and reacted with methyl orange (MO) to form an ion-pair complex, which then further formed a six-membered ring chelate with Pd(II). As a result, new RRS spectra appeared and the RRS intensities were enhanced greatly. RRS spectral characteristics of the MO-QNS-Pd(II) systems, the optimum conditions for the reaction, and the influencing factors were investigated. Under optimum conditions, the scattering intensity (∆I) increments were directly proportional to the concentration of QNS with in certain ranges. The method had high sensitivity, and the detection limits (3σ) ranged from 6.8 to 12.6 ng/mL. The proposed method had been successfully applied for the determination of QNS in pharmaceutical formulations and human urine samples. In addition, the mechanism of the reaction system was discussed based on IR, absorption and fluorescence spectral studies. The reasons for the enhancement of scattering spectra were discussed in terms of fluorescence-scattering resonance energy transfer, hydrophobicity and molecular size.
基于共振瑞利散射（RRS）建立了测定痕量喹诺酮类（QNS）的新方法。在 pH 3.3-4.4 的 Britton-Robinson 缓冲介质中，喹诺酮类如环丙沙星、培氟沙星（PIP）、洛美沙星（LOM）、诺氟沙星（NOR）和沙拉沙星（SAR）质子化后与甲基橙（MO）反应形成离子对复合物，进一步与 Pd(II) 形成六元环螯合物。结果，出现了新的 RRS 光谱，RRS 强度大大增强。研究了 MO-QNS-Pd(II) 体系的 RRS 光谱特征、反应的最佳条件以及影响因素。在最佳条件下，散射强度（∆I）增量与 QNS 的浓度在一定范围内呈正比。该方法具有较高的灵敏度，检测限（3σ）范围为 6.8-12.6ng/mL。该方法已成功应用于药物制剂和人尿样中 QNS 的测定。此外，还通过红外、吸收和荧光光谱研究讨论了反应体系的机理。从荧光-散射共振能量转移、疏水性和分子大小方面讨论了散射光谱增强的原因。
Zotero 插件