硝普钠分光光度法测定对乙酰氨基酚

建立了硝普钠分光光度法测定对乙酰氨基酚的方法。研究表明:在碱性条件下,对乙酰氨基酚与硝普钠以1∶2的化学计量比反应形成一种绿色产物,其最大吸收波长为698nm。对乙酰氨基酚在1.7～102μg·mL-1浓度范围内与吸光度成良好线性关系,线性回归方程为A=0.02804+0.02285c(μg·mL-1),线性相关系数r=0.9986,表观摩尔吸收系数ε698=3.5×103L·mol-1·cm-1,检测限(3s·k-1)为1.42μg·mL-1。本方法成功应用于药物样品中对乙酰氨基酚含量的测定,回收率在97.6%～102.0%,结果满意。     

硝普钠分光光度法测定头孢噻肟钠

建立了测定头孢噻肟钠的新方法,碱性溶液中硝普钠与头孢噻肟钠生成了化学计量比为2∶1的产物,其最大吸收波长λmax=525 nm,表观摩尔吸光系数3.9×103L.mol-1.cm-1。头孢噻肟钠在0.91~200μg/mL浓度范围内与吸光度呈现良好线性关系,线性回归方程A=0.010+0.00816ρ(μg/mL),线性相关系数r=0.9994,检出限(3σ/k)为0.62μg/mL。方法可用于药物样品和血清中头孢噻肟钠含量的测定。     

硝普钠分光光度法测定头孢他啶

建立了硝普钠分光光度法测定头孢他啶的方法。实验结果表明,在碱性条件下,头孢他啶与硝普钠以1∶2的化学计量比反应形成一种红褐色产物,其最大吸收波长为528 nm。 头孢他啶在2.50~810 mg/L浓度范围内与吸光度呈良好线性关系,线性回归方程为A=0.02704+0.00218ρ(mg/L),线性相关系数r＝0.9987,表观摩尔吸收系数ε528=1.2×103 L/(mol·cm),检测限(3σ/k)为1.38 mg/L。 本方法操作简便、快速,成功用于药品中头孢他啶含量的测定。     

硝普钠和盐酸二甲双胍分光光度法相互测定

建立了硝普钠(SNP)和盐酸二甲双胍(MET)分光光度法相互测定的新方法。在碱性条件下,MET与SNP以1:1的化学计量比生成了一种酒红色的物质,其最大吸收波长为524 nm。当固定SNP(6.0×10-3mol/L)为5.00 m L时,吸光度和MET的浓度呈现良好的线性关系,线性回归方程为A=0.008+0.449cM ET(mmol/L),相关系数为0.9997,检出限(3σ/k)为0.02 mmol/L。当固定MET(6.0×10-3mol/L)为5 m L时,吸光度与SNP的浓度呈现良好的线性关系,线性回归方程为A=0.005+0.436cSNP(mmol/L),相关系数为0.9992,检出限(3σ/k)为0.01 mmol/L。方法可用于分别测定药物样品中MET和SNP含量。     

硝普钠显色测定药物样品中甲巯咪唑

在溶液中NaOH浓度为6.7×10-3mol/L及0℃(冰水浴)条件下,反应时间为30 min,硝普钠与甲巯咪唑生成化学计量比为1碱性条件下硝普钠与甲巯咪唑反应生成化学计量比为1∶1的绿色产物,其最大吸收波长为610 nm。甲巯咪唑在4.8~48 mg/L浓度范围内与吸光度呈良好线性关系,线性回归方程为A=-0.0617 0.01329C(mg/L),相关系数r=0.9991;检出限为0.47 mg/L;相对标准偏差RSD=0.2%。本法成功用于测定片剂药品中甲巯咪唑的含量,平均回收率大于97.2%。     

硝普钠分光光度法测定头孢克肟

研究了硝普钠(SNP)与头孢克肟(CEF)之间的显色反应机理,确定了最佳反应条件,建立了一种测定CEF的新方法。结果表明:在NaOH溶液浓度为0.17mol/L的碱性介质中,控制温度40℃,反应30min,CEF与SNP以1∶2化学计量比生成一种含亚硝基的红褐色化合物,最大吸收波长为530nm,表观摩尔吸光系数ε=1.96×103L/(mol·cm)。CEF的浓度在0.8~400μg/mL范围内服从比耳定律,线性相关系数为0.9991,检测限(3σ/k)为0.48μg/mL。     

硝普钠在社区急诊治疗急性左心衰应用观察

目的评价硝普钠在社区急诊治疗急性左心衰中的应用。方法选取广东省电白县旦场卫生院接诊的急性左心衰患者141例,分为观察组71例,选用硝普钠进行治疗,对照组70例,选用硝酸甘油进行治疗,观察并比较两组患者临床疗效以及治疗前后血压、心率变化情况。结果观察组临床疗效优良率为90.1%,对照组为68.6%,两组临床疗效优良率比较差异有统计学意义(P<0.05)。结论硝普钠在社区急诊治疗急性左心衰中的临床疗效好,能有效改善患者血压及心率情况,值得推广。     

硝普钠-铜(Ⅱ)体系的极谱法研究与应用

本文用单扫描极谱法研究了硝普钠(SNP)-铜(Ⅱ)体系的伏安行为。在pH3.0的克拉克-鲁布斯缓冲溶液中,SNP和SNP-Cu2 体系于-0.47 V(vs.SCE)处均有极谱还原峰,但SNP-Cu2 体系的灵敏度是SNP的100倍左右,其峰高与SNP浓度在2.0×10-7~4.0×10-5mol/L范围内呈线性关系,检出限为1.0×10-7mol/L。应用本法测定静脉注射到大白鼠中SNP的含量,结果满意。     

表面活性剂增敏硝普钠分光光度法测定甲硝唑

本文建立了十四烷基二甲基苄基铵增敏作用下硝普钠分光光度法测定甲硝唑的方法.研究表明:在碱性条件下,甲硝唑与硝普钠反应生成化学计量比为1:1的红褐色产物,其最大吸收波长λmax=500nm,表观摩尔吸光系数为ε=9.8×103L·mol-1·cm-1.甲硝唑在0.70～30μg·mL-1浓度范围内与吸光度成良好线性关系,...     

在丙酮增敏作用下硝普钠分光光度法测定盐酸吗啉胍

摘要：建立了可见分光光度法测定盐酸吗啉胍的新方法。研究表明,当NaOH浓度为0.13mol/L,在丙酮存在下硝普钠与盐酸吗啉胍反应生成紫色N-亚硝基类化合物,其最大吸收波长为508nm,表观摩尔吸光系数2.5×10³ L/（mol•cm）。盐酸吗啉胍浓度在0.38×10^-6~3.0×10^-4 g/mL范围内与吸光度呈现良好线性关系,线性回归方程A = 0.02292 + 0.01213c (10^-6 g/mL),线性相关系数r=0.9998,检测限(3σ/k)为0.25×10^-6 g/mL,RSD = 0.21%。本方法可用于药物样品和血清中盐酸吗啉胍含量的测定。     

亚硝基铁氰化钠分光光度法测定药品“必理通”中对乙酰氨基酚含量

用亚硝基铁氰化钠分光光度法测定药品“必理通”中的对乙酰氨基酚含量。采用亚硝基铁氰化钠试液为显色剂,蒸馏水做溶剂,在波长为700nm下有最大吸收,利用分光光度计测定不同浓度溶液的吸光度,并绘制标准曲线进行分析。实验证明,对乙酰氨基酚在0．024mg／mL～0．168mg／mL浓度范围内,吸光度与样品浓度的线性关系良好,回收率在98．0％以上。此测定方法准确、快速、简便,是测定对乙酰氨基酚含量的最佳方法之一。     

Spectrophotometric Determination of Hydroxylamine,Glycine and Methionine by Using Sodium Nitroprusside as a Complexing Agent

Abstract

The spectrophotometric determination of hydroxylamine, glycine and methionine has been investigated. The high molar absorptivity of the investigated amino acids or hydroxylamine-nitroprusside complexes at the optimum conditions indicates that concentrations of 10^?4?10^?3 M of these compounds can be determined spectrophotometrically with fair accuracy. The effect of pH was studied and the optimum pH was chosen to give the highest sensitivity. The validity of this method is supported by the constancy of the absorptivity of the investigated compounds and the statistical data of regression analysis.     

Rapid and Convenient Method for the Determination of Sodium Nitroprusside in Aqueous Solution

Abstract

We propose a rapid and convenient method for the determination of sodium nitroprusside in aqueous solution. In alkaline medium and in the presence of dimethylsulfoxide, the concentration of the nitrite ions coming from the nitroprusside corresponds with the initial quantity of this compound.     

The Nitric Oxide (NO) Donor Sodium Nitroprusside (SNP) and Its Potential for the Schizophrenia Therapy: Lights and Shadows

Schizophrenia is a severe psychiatric disorder affecting up to 1% of the worldwide population. Available therapy presents different limits comprising lack of efficiency in attenuating negative symptoms and cognitive deficits, typical features of schizophrenia and severe side effects. There is pressing requirement, therefore, to develop novel neuroleptics with higher efficacy and safety. Nitric oxide (NO), an intra- and inter-cellular messenger in the brain, appears to be implicated in the pathogenesis of schizophrenia. In particular, underproduction of this gaseous molecule is associated to this mental disease. The latter suggests that increment of nitrergic activity might be of utility for the medication of schizophrenia. Based on the above, molecules able to enhance NO production, as are NO donors, might represent a class of compounds candidates. Sodium nitroprusside (SNP) is a NO donor and is proposed as a promising novel compound for the treatment of schizophrenia. In the present review, we intended to critically assess advances in research of SNP for the therapy of schizophrenia and discuss its potential superiority over currently used neuroleptics.     

Assay of Phenformin Hydrochloride in Pharmaceutics by Coupling with Sodium Nitroprusside

A novel and simple spectrophotometric method for the determination of phenformin hydrochloride using sodium nitroprusside as chromogenic reagent is developed in this paper. The experiment indicates that the sodium nitroprusside can react with the phenformin hydrochloride in a basic solution to form a product with colored N‐nitrosamines. The stoichiometric ratio of phenformin hydrochloride and sodium nitroprusside is 1:3 in the product. The maximal absorption wavelength (λ_max) of the product is 520 nm, ?₅₂₀ = 2.2 × 10³ Lmol^?1cm^?1. A Good linear relationship is obtained between the absorbance (A) and the concentration (C) of phenformin hydrochloride in a wide range of 0.20‐400 μg mL^?1. The equation of the linear regression is A = 0.03461 + 0.00907C (μg mL^?1) with a linear correlation coefficient of 0.9991. The detection limit is 0.13 μg mL^?1, and the relative standard deviation (R.S.D.) is 0.19%. The method is successfully applied to the determination of phenformin hydrochloride in tablet forms, and satisfactory recoveries are obtained.     

Utilization of Sodium Nitroprusside as an Intestinal Permeation Enhancer for Lipophilic Drug Absorption Improvement in the Rat Proximal Intestine

As advanced synthetic technology has enabled drug candidate development with complex structure, resulting in low solubility and membrane permeability, the strategies to improve poorly absorbed drug bioavailability have attracted the attention of pharmaceutical companies. It has been demonstrated that nitric oxide (NO), a vital signaling molecule that plays an important role in various physiological systems, affects intestinal drug absorption. However, NO and its oxidants are directly toxic to the gastrointestinal tract, thereby limiting their potential clinical application as absorption enhancers. In this study, we show that sodium nitroprusside (SNP), an FDA-approved vasodilator, enhances the intestinal absorption of lipophilic drugs in the proximal parts of the small intestine in rats. The SNP pretreatment of the rat gastrointestinal sacs significantly increased griseofulvin and flurbiprofen permeation in the duodenum and jejunum but not in the ileum and colon. These SNP-related enhancement effects were attenuated by the co-pretreatment with dithiothreitol or c-PTIO, an NO scavenger. The permeation-enhancing effects were not observed in the case of antipyrine, theophylline, and propranolol in the duodenum and jejunum. Furthermore, the SNP treatment significantly increased acidic glycoprotein release from the mucosal layers specifically in the duodenum and jejunum but not in the ileum and colon. These results suggest that SNP increases lipophilic drug membrane permeability specifically in the proximal region of the small intestine through disruption of the mucosal layer.     

A Novel Method for the Determination of Streptomycin Using Sodium Nitroprusside as a Chromogenic Reagent by Spectrophotometry

Abstract

A rapid and simple spectrophotometric method for the determination of streptomycin has been developed and validated. The method was based on the reaction of streptomycin with sodium nitroprusside in the alkaline medium forming a red product measured at the maximum absorption of 495 nm. The stoichiometric ratio of the product is 1:1. Beer's law is obeyed in a range of 1.87 µg mL^?1 ～ 279.8 µg mL^?1 of streptomycin and ?₄₉₅ is 6.0 × 10³ L·mol^?1 cm^?1.Under the optimum condition, the equation of linear regression is A = 0.00742 + 0.05683 C (× 10⁵ mol·L^?1), with a linear correlation coefficient of 0.9990. The detection limit (3σ/k) is 0.96 µg mL^?1, the relative standard deviation (RSD) is 2.40%, and the average recovery rate is 98.3%–102.7%. Every parameter has been optimized, and the reaction mechanism has been studied. The proposed method has been successfully applied to the determination of streptomycin for injections and tablets of pharmaceutical preparation. Analytical results obtained by this new method were very gratifying.