Résumé
A sensitive chemiluminescence(CL) method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe(CN)6 system in alkaline medium.The determination conditions were optimized.Under optimum conditions,the chemiluminescence intensity had a good linear relationship with melamine in the range of 9.0 × 10 97.0 × 10 6 g/mL with a correlation coefficient of 0.9992.The detection limits (3σ) were 3.54 ng/mL for urine sample and 6.58 ng/mL for plasma sample.The average recoveries of melamine were 102.6％ for urine sample and 95.1％ for plasma sample.Melamine in samples was extracted with liquid-liquid extraction procedures and the assay results coincided very well with that determined with flow injection chemiluminescence method.The method provides a reproducible and stable approach for sensitive detection and quantification of melamine in urine and plasma samples.
Résumé
A novel high performance liquid chromatographic method was developed for the determination of 4-O-methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation.Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins.A reverse phase column of SHIMPACK VP-ODS (150 mm× 4.6 mm,5.0 μm) was used to separate 4-O-methylhonokiol in the plasma samples.The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0.012- 1.536 mg/L.The good extraction recoveries were obtained for the spiked samples (84.7％,89.3％ and 87.7％ for low,middle and high concentrations of added standards,respectively).The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6％ to 13.5％.The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-O-methylhonokiol showed a two-apartment open model.This work developed a sensitive,stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.
Résumé
A novel flow injection chemiluminescence (CL) method for the determination of loxoprofen and naproxen was proposed based on the CL system of KMnO4 and Na2 SO3 in acid media.The CL intensity of KMnO4-Na2 SO3 was greatly enhanced in the presence of loxoprofen and naproxen.The mechanism of the CL reaction was studied by the kinetic process and UV-vis absorption and the conditions were optimized.Under optimized conditions,the CL intensity was linear with loxoprofen and naproxen concentration in the range of 7.0 × 10- 8 - 1.0 × 10 5 g/mL and 2.0 × 10 7 - 4.0 × 10 6 g/mL with the detection limit of 2.0 × 10 8g/mL and 3.0 × 10 sg/mL (S/N =3),respectively.The relative standard deviations were 2.39％ and 1.37％ for 5.0 × 10- 7 g/mL naproxen and 5.0 × 10 7 g/mL loxoprofen ( n =10),respectively.The proposed method was satisfactorily applied to the determination of loxoprofen and naproxen in pharmaceutical preparations.
Résumé
A sensitive chemiluminescence（CL） method was developed for determining melamine in urine and plasma samples based on the fact that melamine can remarkably enhance the chemiluminescence of Luminol-K3 Fe（CN）6 system in alkaline medium. The determination conditions were optimized. Under optimum conditions, the chemiluminescence intensity had a good linear relationship with melamine in the range of 9.0 × 10
Résumé
A novel high performance liquid chromatographic method was developed for the determination of 4-O- methylhonokiol in rabbit plasma and was applied to its pharmacokinetic investigation. Plasma samples were treated by one-fold volume of methanol and acetonitrile to remove the interference proteins. A reverse phase column of SHIM- PACK VP-ODS （150 mm ×4.6 mm, 5.0 μm） was used to separate 4-O-methylhonokiol in the plasma samples. The detection limit of 4-O-methylhonokiol was 0.2 μg/L and the linear range was 0. 012 - 1. 536 mg/L. The good extraction recoveries were obtained for the spiked samples （84.7%, 89.3% and 87.7% for low, middle and high concentrations of added standards, respectively）. The relative standard deviation of intra-day and inter-day precisions was in the range from 0.6% to 13.5%. The pharmacokinetic study of 4-O-methylhonokiol was made and the results from the plasmaconcentration curve of 4-0-methylhonokiol showed a two-apartment open model. This work developed a sensitive, stable and rapid HPLC method for the determination of 4-O-methylhonokiol and the developed method has been successfully applied to a pharmacokinetic study of 4-O-methylhonokiol.
Résumé
A novel flow injection chemiluminescence（CL）method for the determination of loxoprofen and naproxen was proposed based on the CL system of KMnO4 and Na2SO3 in acid media.The CL intensity of KMnO4-Na2SO3 was greatly enhanced in the presence of loxoprofen and naproxen.The mechanism of the CL reaction was studied by the kinetic process and UV-vis absorption and the conditions were optimized.Under optimized conditions,the CL intensity was linear with loxoprofen and naproxen concentration in the range of 7.0×10
Résumé
Objective To establish a rapid, accurate and sensitive chemiluminescence method for determining sulfydryl-containing drugs. Methods In sulfuric acid solution, glyoxal could be oxidized by potassium permanganate, and weak chemiluminescence could be observed. Chemiluminescence signal could be enhanced in the presence of sulfydryl-containing drugs. Thus, on this basis we established a new method of determining the concentration of sulfydryl-containing drugs with flow injection chemiluminescence analysis. Results Under the optimized conditions, the linear range of methimazole, captopril and acetylcysteine was 1.0×10~(-8)- 5.0×10~(-6), 7.0×10~(-8)-1.0×10~(-6) and 3.0×10~(-8)-1.0×10~(-6)g/mL, respectively. The limit of detection of methimazole, captopril and acetylcysteine was 1.0, 3.9 and 3.7ng/mL, respectively. Conclusion The method was successfully applied to determine the three drugs that contain sulfydryl. Compared with the results of pharmacopeia methods, the results we obtained were satisfactory.
Résumé
Objective To develop a rapid, simple and sensitive chemiluminescence method for the determination of three β-blockers (bisoprolol, atenolol and propranolol). Methods The chemiluminescence of cerium (Ⅳ)-sulfite system was obviously sensitized by adding anyone of three β-blockers in acid media. A new chemiluminescence method was set up by combining with flow-injection technique and used to determine the three β-blockers. Results Good linear ranges were obtained at the concentrations of 2.0×10-7g/mL-4.0×10-5g/mL, 1.0×10-7g/mL-3.0×10-5g/mL and 7.0×10-7g/mL-1.0×10-5g/mL, respectively, with the detection limits of 5.0×10-8g/mL, 7.0×10-8g/mL and 5.0×10-8g/mL (S/N=3), respectively, and the relative standard deviations for 11 times consecutive injections of 1.0×10-6g/mL bisoprolol, atenolol and propranolol were 3.57%, 2.21% and 2.26%, respectively. Conclusion The developed method is sensitive, accurate, rapid and of low cost. And it can be applied to determine bisoprolol, atenolol and propranolol in pharmaceutical preparations.
Résumé
Objective To establish a novel method for simultaneous determination of three ingredients (codeine phosphate, brompheniramine maleate and ephedrine hydrochloride) in compound codeine phosphate solution by using capillary electrophoresis (CE) coupled with electrochemiluminescence (ECL). Methods Based on enhanced ECL intensity of tris (2,2′-bypyridine) ruthenium (Ⅱ) with codeine phosphate, brompheniramine maleate and ephedrine hydrochloride, as well as the linear correlation between enhanced sensitivity intensity and drug concentration, Parameters affecting separation and detection were optimized. Results Under the optimized conditions, we determined the linear range, regression equation and detection limit for the three ingredients. The relative standard deviation of ECL intensity for twelve consecutive injections of 1.0×10~(-5)kg/L standard sample of three kinds of drug was 2.89% for codeine phosphate, 3.76% for brompheniramine maleate and 3.32% for ephedrine hydrochloride, respectively. Satisfactory results were obtained without interference from sample matrixes. Conclusion The method was successfully applied to the determination of three ingredients in oral solution of compound codeine phosphate, with the recovery rate of 100.4% for codeine phosphate, 101.9% for brompheniramine maleate and 99.8% for ephedrine hydrochloride.
Résumé
Objective: To establish a rapid and precise continuous flow-injection chemiluminescence method for the determination of tetracycline and oxytetracycline. Methods: In NaOH solution, tetracycline and oxytetracycline can sensitize obviously the chemiluminesence (CL) intensity of the reaction of luminol with KIO4, the sensitized CL intensity is proportional to the concentration of tetracycline and oxytetracycline. So, a new flow-injection CL method has been developed. The optimum chemical conditions for the CL reaction were investigated. Results: Under the optimized conditions (KIO4 concentration: 1.0×10-5 mol/L; NaOH concentration: 0.1 mol/L; luminol concentration: 1.0×10-4 mol/L), tetracycline and oxytetracycline were determined. The linear range of the working curves was 1.0×10-7 -1.0×10-4 g/mL, the detection limits was 1.0×10-8 g/mL and 1.1×10-8 g/mL, and the relative standard deviation was 2.6% (Cs = 1.0×10-6 g/mL; n=11) and 2.0% (Cs = 1.0×10-6 g/mL; n=11) respectively. Conclusion: The method is simple, rapid, and sensitive, and it has been successfully applied to the the determination of tetracycline and oxytetracycline tablets, the mean recoveries being 99.7% and 98.8% respectively.
Résumé
Objective To establish a rapid and precise continuous flow-injection chemiluminescence method for the determination of tetracycline and oxytetracycline. Methods In NaOH solution, tetracycline and oxytetracycline can sensitize obviously the chemiluminesence (CL) intensity of the reaction of luminol with KIO4, the sensitized CL intensity is proportional to the concentration of tetracycline and oxytetracycline. So, a new flow-injection CL method has been developed. The optimum chemical conditions for the CL reaction were investigated. Results Under the optimized conditions (KIO4 concentration: 1.0×10-5 mol/L; NaOH concentration: 0.1mol/L; luminol concentration: 1.0×10-4mol/L), tetracycline and oxytetracycline were determined. The linear range of the working curves was 1.0×10-7 -1.0×10-4g/mL, the detection limits was 1.0×10-8g/mL and 1.1×10-8g/mL, and the relative standard deviation was 2.6% (CS=1.0×10-6g/mL; n=11) and 2.0% (CS=1.0×10-6g/mL; n=11) respectively. Conclusion The method is simple, rapid, and sensitive, and it has been successfully applied to the the determination of tetracycline and oxytetracycline tablets, the mean recoveries being 99.7% and 98.8% respectively.
Résumé
Objective To establish a rapid and precise continuous flow-injection chemiluminescence (CL) method for the determination of perphenazine. Methods In HNO_3 medium, perphenazine could be oxidated by ceriuim (IV) and CL was proportional to the perphenazine concentration without any sensitizers. Thus, a new flow-injection CL method was developed. Results Under the optimized conditions, the proposed method allowed the determination range within 1.0?10~ -7 -7.0?10~ -5 g/mL with the detection limit of 8.0?10~ -8 g/mL. Eleven parallel assays were conducted on perphenazine of 1.0?10~ -6 g/mL, with the relative standard deviation of 1.8%. Conclusion The method is simple, rapid, precise, and sensitive, and has broad linear range; therefore, it has been applied to the the determination of the perphenazine in tablets with satisfactory results.
Résumé
Objective To study the protective effect of Res o n myocardial ischemic/reperfused induced injury. Methods My ocardial ischemic/reperfusion model was used to study the protective effect of d ifferent dosage resvaratrol on myocardial ischemic/reperfusion injury in rats. Results Res shrinked the size of myocardial infarction indu ced by the ischemic reperfused method, inhibited the release of creatine kinase( CK) and lactate dehydrogenase(LDH) from the injured myocardium and reduced elega ted ST-T of electrocardiogram(ECG) caused by myocardial ischemic-reperfused in jury in dose-dependent way. Res also improved the morphological changes of inju red myocardium. Conclusion Res has protective action on myo cardial ischemic reperfused injury in rats.
Résumé
Objective To investigate the ex tr action technique for seperating the active components in the root of Salvia mi ltiorrhizae bunge by supercritical fluid, and to analyze the extracted product s by HPLC-MS n . Methods The extraction condition s were established as follows: 950ml?L -1ethanol as the first entrainer, t he pressure of 20.0 MPa, temperature at 45 ℃, and extracting time 1 h; then 100 mL?L -1 ethanol was selected as the second entrainer, pressur e was 30.0 MPa, temperature was 65 ℃, and extracting time was 3 h. Results Compared with traditional refluxing extraction and ultrasonic extraction, supercritical fluid extraction was better and more effect ive. Conclusion Supercritical extraction is simple, highly selec tive and efficient in extracting the active components in Salvia miltiorrhizae bunge.
Résumé
Objective To develop a new flow-injection chemiluminescence(FI-CL) method for the determination of acyclovir and gancyclovir by using the CL system of Ce(IV)-Rhodamine B.Methods The redoxreaction of Ce(IV) and acyclovir/gancyclovir in H2SO4 medium could generate CL signal.Rhodamine B could obviously sensitize this signal,and the CL intensity was proportional to the concentration of acyclovir and gancyclovir.Therefore,a new FI-CL method has been described for the determination of acyclovir and gancyclovir.Results For acyclovir,the determination range was 3.0?10-5g/L-7.0?10-2g/L,with 1.56?10-5g/L as its determination limit.During 11 repeated measurements for 1.0?10-3g/L acyclovir,the relative standard deviation was 2.08%.For ganciclovir,the determination range was 5.0?10-5g/L-7.0?10-2g/L,with 2.35?10-5g/L as its determination limit.The relative standard deviation was 2.83%,with 11 repeated measurements of 1.0?10-3g/L ganciclovir.Conclusion This method has broad linear range,high sensitivity,and convenience and speediness,it therefore,can be successfully used to determine the content of ganciclovir in injections.
Résumé
Objective To ascertain whether the growth inhibitor in conditioned medium from cultured rabbit arte rial cells is distinct from TGF-β. Methods Rabbit aortic smooth muscle ceils were grown from explained segments of the aorta. Conditioned medium from cultured rabbit aortic smooth muscle ceils and anti-TGF-β were employed in this study. Smooth muscle cell proliferation was measured by XTT detection (Boehringer Mannheim). Results Acidified conditioned medium from smooth muscle ceils had significantly stronger effects of growth inhibition than controls, and anti-TGF-β did not affect the growth inhibitory effect of conditioned medium from cultured rabbit arterial smooth muscle cells. Conclusion The growth inhibiting substance in conditioned medium from cultured rabbit aortic smooth muscle cells is distinct from TGF-β.
Résumé
Objective To establish a speed and effective method to detect rotavirus. Methods Using ELISA and one step RT-PCR to detect 196 clinic samples from Xi'an area. Results Compared with ELISA method, one step RT PCR was more sensitive and specific (P ＜0.05). Conclusion One step RT-PCR is a simple, speed, sensitive and spe cific method for clinic and epidemic studies of rotavirus.
Résumé
Objective To establish a new flow-injection chemiluminescence(CL) method for the determination of hydrocortisone.Methods In H2SO4 solution,hydrocortisone could obviously enhance the chemiluminescence intensity of the reaction of KMnO4-Na2SO3 system.Based on this,a new flow-injection CL method for the determination of hydrocortisone was developed.Results There was a good linear relationship between CL intensity and the concentration of hydrocortisone in the range of 1.0?10-9-1.0?10-6g/mL.The detection limit was 4.0?10-10g/mL at a signal-to-noise ratio of 3∶1.The RSD of 11 assays was 2.2%.Conclusion This method can be successfully used to determine the quantity of hydrocortisone in injection.It is rapid,accurate,simple,and has high sensitivity and wide linear range.