共振瑞利散射光谱法测定血浆和尿样中的帕珠沙星

目的建立了共振瑞利散射光谱法测定血浆、尿样中帕珠沙星含量的新方法。方法于pH4.8～5.9的Britton-Robinson缓冲溶液中,帕珠沙星与钴(Ⅱ)形成阳离子配合物,其共振瑞利散射(resonance rayleigh scattering,RRS)十分微弱,但当其进一步通过静电引力和疏水作用与刚果红(congo red,CR)阴离子反应形成三元离子缔合物时,RRS出现新的共振瑞利散射光谱,其2个散射峰分别位于380和562nm处。结果在380nm处,帕珠沙星的质量浓度在0.031～3.18μg.mL-1范围内,与RRS强度有良好的线性关系,其检出限(3σ)为24.6ng.mL-1。结论该方法简单、快速,具有良好的选择性和重复性,可用于不同体液中帕珠沙星的测定。     

透明质酸钠-溴化十六烷基吡啶缔合物体系的共振瑞利散射光谱及其应用

在pH 4.3的Britton-Robinson缓冲溶液中,透明质酸钠和溴化十六烷基吡啶各自单独存在时,共振瑞利散射(RRS)强度非常弱,但当两者反应形成离子缔合物时,RRS大大增强并产生新的RRS光谱,最大RRS峰位于335 nm处.透明质酸钠在0.1～3.0 μg/ml浓度范围内与RRS强度成正比.据此,建立了共振瑞利散射光谱法测定透明质酸钠,检测限为29ng/ml.     

共振瑞利散射法测定多柔比星脂质体中游离多柔比星的含量

目的:建立共振瑞利散射法(RRS)测定多柔比星(DOX)脂质体中游离 DOX 含量。方法:在 pH 2.6的 Britton-Robinson(BR)缓冲液中,刚果红(CR)与 DOX 通过分子间作用力形成离子缔合物,在λ_(ex)=λ_(em)=380 nm 波长时能使 RRS 信号显著增强。结果:RRS 法在1～12 μg·mL~(-1)范围内呈线性关系,检出限为0.05~(-1)g·mL~(-1)。对6个不同批号的 DOX 脂质体混悬液中游离 DOX 的含量测定,结果与紫外可见分光光度法相符,RSD(n=6)为1.9%～3.2%,平均回收率为94.3%。结论:此方法灵敏度较高,可以用于测定 DOX 脂质体中游离 DOX 的含量。     

高灵敏共振瑞利散射技术快速检测药物中的美司那

目的 建立快速、准确测定药物中美司那的高灵敏共振瑞利散射新方法。方法 在BR 弱碱性溶液中,亮绿与美司那以静电作用生成的缔合物使共振瑞利散射(RRS)信号显著增强,RRS 强度在最大共振瑞利散射峰处与美司那的浓度有线性关系。检测波长：344 nm。结果 在pH 7.75 BR缓冲溶液中,亮绿与美司那结合生成绿色二元离子缔合物,产生以294 nm、344 nm 和468 nm 为特征峰的新共振瑞利散射光谱。最大共振瑞利散射峰位于344 nm,线性范围为0.006～0.41 mg/L,检出限为0.0052 mg/L。该法用于市售美司那药物中美司那的测定,加标回收率和相对标准偏差(RSD,n=6)分别为98.3%～103% 和1.6%～2.3%。结论 该法简便、快速,有高灵敏度和高选择性,用于实际药物中美司那的测定,结果满意。     

小檗碱-四苯硼钠缔合纳米微粒体系的共振Rayleigh散射光谱及其分析应用小檗碱-四苯硼钠缔合纳米微粒体系的共振Rayleigh散射光谱及其分析应用

目的研究(小檗碱-四苯硼钠)_n缔合纳米微粒的形成与共振Rayleigh散射之间的关系，建立测定小檗碱的共振Rayleigh散射光谱分析新方法。方法采用共振Rayleigh散射光谱法、吸收光谱和透射电镜研究四苯硼钠(TPB)与盐酸小檗碱(BB)的缔合反应。结果在pH 5.0 NaAc-HAc缓冲溶液中，TPB与BB结合形成的(BB-TPB)_n缔合纳米微粒在470 nm处产生一个共振Rayleigh散射（RRS）峰。建立了测定0.06～5.28 mg·L^-1盐酸小檗碱的RRS新方法，检出限为26 μg·L^-1。 结论通过TPB－与BB⁺和Ag⁺反应形成可用透射电镜观测的(BB_jAg_p-TPBj+p)h复合缔合纳米微粒，证实了固液界面的形成是导致其共振Rayleigh散射光增强的充分必要条件。建立的RRS新方法可用于中成药中微量小檗碱的测定，具有灵敏度高，试样用量少等特点。     

丽春红的共振散射光谱法测定木瓜蛋白酶的活力

目的 建立一种测定木瓜蛋白酶活力的共振散射(RS)新方法.方法 在一定的条件下,丽春红S与酪蛋白形成的缔合微粒产生较强的共振散射信号和两个散射峰.基于木瓜蛋白酶催化酪蛋白水解,丽春红S与剩余酪蛋白结合,木瓜蛋白酶活力的增加,体系的共振散射强度(Ⅰ)降低.结果 在pH=6.24的Sφrensen缓冲溶液、最强散射波长580 nm处,酶活力在0.008～0.195 USP/mL范围内,RS强度的降低(△Ⅰ)与酶活力的增加有良好的线性关系,检出限为0.007 USP/mL.结论 建立了以丽春红S为RS探针的测定木瓜蛋白酶活力的新方法,操作简便、快速,灵敏度高,可用于实际样品中酶活力的测定.     

反相高效液相色谱法有效分离和同时测定人体尿液中7种喹诺酮

目的 建立一种同时检测人体尿液中吡哌酸与依诺沙星、氟罗沙星、培氟沙星、洛美沙星、环丙沙星和恩氟沙星7种氟喹诺酮类药物的反相高效液相色谱法.方法 色谱柱为ZY1104型C18色谱柱(250 mm×4.6mm,5μm),柱温30℃.流动相为乙腈0.02mol/L四丁基溴化铵(体积比为991).以三氟乙酸缓冲液调pH 2.87,流速1.0ral/min.检测波长282nm,进样量20μl.结果 7种药物的校准曲线在0.5～100μg/ml浓度范围内呈良好的线性,相关系数r≥0.9996,检出限为0.036～0.088ttg/ml.样品的平均加标回收率在91.6%～99.5%,RSD＜7%(n=5).结论 所提出的方法简便,快速,可靠,能有效分离和同时测定人体尿液中的多种喹诺酮.     

甲磺酸培氟沙星胶囊及其在人尿液中含量的铕敏化荧光法测定

在pH 5.9醋酸盐缓冲溶液中,甲磺酸培氟沙星和铕(Eu3 )、EDTA易形成2:1:1的三元配合物,产生Eu3 的特征荧光.由此建立了铕敏化荧光法测定甲磺酸培氟沙星胶囊及其在人尿液中的含量.     

HPLC法测定甲磺酸培氟沙星片含量及有关物质

目的:建立高效液相色谱法测定甲磺酸培氟沙星片中药物及有关物质.方法:色谱柱为C18柱(150 mm×6 mm,5 μm),流动相为乙腈-2.70 g/L十六烷基三甲基溴化氨与6.18 g/L硼酸溶液的混合溶液(用1 mol/L氢氧化钠溶液准确调pH至8.30)-硫二甘醇(30:70:0.2),检测波长为273 nm.结果:甲磺酸培氟沙星在17.18～85.90 μg/mL范围内与峰面积呈良好的线性关系(r=0.999 9),其平均回收率为99.50%、99.71%、99.62%.最低检测限和定量限分别为0.01989 ng和0.08517 ng,与杂质及喹诺酮类同系物能有效分离.结论:本方法操作简便、结果准确、专属性强,可用于甲磺酸培氟沙星片中药物含量及有关物质的检测.     

维多利亚蓝B共振光散射光谱法测定利福平

目的 建立测定痕量利福平的高灵敏共振瑞利散射法.方法 在弱碱性Tris-盐酸缓冲介质中,维多利亚蓝B与利福平反应后生成的络合物能使共振瑞利散射显著增强,在345nm处,增强的共振光散射强度△IRRS与一定浓度范围的利福平线性相关.结果 在345nm处,利福平的质量浓度在0.016～0.83mg/L范围内与△IRRS成正比,方法的检出限(3Sb/S)为0.0029mg/L.结论 本方法用于尿样及市售利福平药物中利福平含量的测定,RSD小于1.2％,样品加标回收率为98.5％100.6％,结果满意.     

共振瑞利散射法测定微量唑来膦酸

建立了共振瑞利散射法测定微量唑来膦酸。在酸性条件下,唑来膦酸被破坏后产生的无机磷进一步与钼酸铵结合形成磷钼杂多酸,再与罗丹明B形成磷钼杂多酸-罗丹明B三元离子缔合物后共振瑞利散射急剧增加,并于370nm处有最大散射峰,唑来膦酸在6.25～100ng/ml浓度范围内线性关系良好,检测限为1.55ng/ml。     

A highly sensitive resonance Rayleigh scattering method for the determination of bleomycinA5 and bleomycinA2 with some halofluorescein dyes

In a weak acidic medium, bleomycinA(5) (BLMA(5)) and bleomycinA(2) (BLMA(2)) can react with halofluorescein dyes such as erythrosine (Ery), eosin Y (EY), eosin B (EB) and Rose Bengal (RB) by virtue of electrostatic attraction and hydrophobic force to form ion-association complexes, which can result in the large-scale enhancement of resonance Rayleigh scattering (RRS) and the appearance of new RRS spectra. The increments of scattering intensity (Delta I) were directly proportional to the concentrations of bleomycin (BLM) in certain ranges. The detection limits for BLMA(5) and BLMA(2) ranged from 0.017 to 0.062 microg ml(-1). The Ery system had the highest sensitivity and its detection limit (3sigma) was 0.017 microg ml(-1) for BLMA(5) and 0.018 microg ml(-1) for BLMA(2), respectively. Using Ery as a RRS probe, a new highly sensitive method for the determination of BLM anticancer drugs has been developed. It was applied in the determination of BLMA(5) and BLMA(2) in serum and urine samples. The recovery was from 99.0% to 103.0%. In this work, the RRS spectral characteristics of the binding products and the optimum conditions of the reaction were investigated. The mechanism of ion-association reaction and the reasons of enhancement of resonance light scattering were discussed.     

A sensitive and simple method for the determination of chondroitin sulfate a with crystal violet by resonance rayleigh scattering technique

Resonance Rayleigh scattering (RRS) spectra resulting from interaction between chondroitin sulfate A (CSA) and crystal violet (CV) have been investigated and applied to the determination of CSA. Though the intensity of RRS has proved very weak for CSA and CV, respectively, it can be greatly enhanced when both interact and form a supramolecular complex. A new RRS spectrum appears with a maximum scattering peak at 328 nm. In this paper, the optimum conditions of the interaction, influencing factors, and the relationship between the relative intensity of RRS (DeltaI) and the concentration of CSA have been thoroughly investigated. A new method of determination for the trace amount of CSA has been developed, which combines a simple procedure, high sensitivity, and a low detection limit of 4.8 ng/mL. It has been applied with satisfactory results to the determination of CSA in CSA injection samples and synthetic samples.     

阿莫西林与甲基紫的共振瑞利散射及应用

目的建立测定痕量阿莫西林的共振瑞利散射法。方法以甲基紫作探针的共振瑞利散射法测定阿莫西林。结果在pH 9.90的Tris-HCl溶液中,阿莫西林和甲基紫相互作用后,共振瑞利散射显著增强,在376 nm处的△IRRS最强。阿莫西林的浓度在2.0×10-8~1.5×10-6 mol.L-1内与△IRRS成正比,检出限（3Sb/S）为0.042μg.mL-1。结论该法简便、快速、灵敏,可用于痕量阿莫西林的测定。     

Quinolones and colonization resistance in human volunteers

The suppression of alimentary canal flora by the three quinolones nalidixic acid, ciprofloxacin and pefloxacin was investigated in fifteen volunteers. They received the three quinolone compounds in tablet form both uncoated and colon-coated.Escherichia coli suppression was poor under nalidixic acid, but complete under ciprofloxacin and pefloxacin for both administration forms. The indigenous anaerobic flora contributing to the control of aerobicStreptococcus faecalis andCandida albicans in the intestines ('colonization resistance') was not affected by nalidixic acid and pefloxacin, and only slightly by ciprofloxacin. Out of the three quinolone compounds, only colon-coated pefloxacin was associated with a considerable absorption rate at colonie level. Using these criteria of successfulEscherichia coli clearing from the intestinal canal - left the indigenous flora more or less intact (in a 'selective' way) - and a good absorption rate, pefloxacin is found to be superior to ciprofloxacin and nalidixic acid. These results suggest that a colon-coated tablet with a low dose of pefloxacin is a promising administration form in the therapy of recurrent urinary tract infections and diarrhoeal diseases and in the prevention of gut colonization in immunocompromised hosts.     

Pharmacokinetics of pefloxacin and its interaction with cyclosporin A, a P-glycoprotein modulator, in rat blood, brain and bile, using simultaneous microdialysis

1. In vivo microdialysis with HPLC was used to investigate the pharmacokinetics of pefloxacin and its interaction with cyclosporin A. Microdialysis probes were inserted into the jugular vein/right atrium, the striatum and the bile duct of male Sprague-Dawley rats. Biological fluid sampling thereby allowed the simultaneous determination of pefloxacin levels in blood, brain and bile. 2. Following pefloxacin administration, the brain-to-blood coefficient of distribution was 0.036. This was calculated by dividing the area under the concentration curve (AUC) of pefloxacin in brain by its AUC in blood (k=AUC(brain)/AUC(blood)). 3. When the P-glycoprotein cyclosporin A (10 mg kg(-1)) was co-administered with pefloxacin (10 mg kg(-1)), the AUC and the mean residence time in rat blood did not differ significantly (P>0.05). Similarly, the pharmacokinetics of pefloxacin in rat brain was not affected by the presence of cyclosporin A. 4. The AUC of unbound pefloxacin in bile was significantly greater than that in blood. The disposition of pefloxacin in rat bile shows a slow elimination phase following a peak concentration 30 min after pefloxacin administration (10 mg kg(-1), i.v.). The bile-to-blood coefficient of distribution (k=AUC(bile)/AUC(blood)) was 1.53. 5. The results indicated that pefloxacin was able to penetrate the blood-brain barrier and that the concentration in bile was greater than that in the blood, suggesting active biliary excretion of pefloxacin. Current data obtained from rats show no significant impact of cyclosporin A on the pharmacokinetics of pefloxacin in rat blood and brain when administered by concomitant i.v. bolus.     

Comparison of norfloxacin and pefloxacin in the prophylaxis of bacterial infection in neutropenic cancer patients.

In this study the efficacy of norfloxacin and pefloxacin for the antibacterial prophylaxis of granulocytopenia was compared in cancer patients following cytostatic treatment. A total of 136 patients was randomly selected to receive either norfloxacin or pefloxacin. Nineteen patients remained afebrile in the norfloxacin group compared with thirty one in the pefloxacin group (p = 0.045). Twenty four microbiologically documented infections (twelve with and twelve without bacteraemia) occurred in sixty seven patients taking norfloxacin, and twelve in sixty nine patients taking pefloxacin (five with and seven without bacteraemia) (p = 0.015). Only one infection caused by Gram-negative bacilli was observed in the pefloxacin group compared with seven in the norfloxacin group (p = 0.019). In conclusion, both microbiological and clinical results showed pefloxacin to be a better antibacterial agent than norfloxacin for these patients.