顶空-气相色谱法测定葡萄糖氯化钠注射液中12种溶剂残留量

建立顶空-气相色谱法测定葡萄糖氯化钠注射液中12种残留溶剂含量的方法。采用HP-INNOWAX毛细管色谱柱(60 m×320μm,0.5μm)为分离柱,检测器为氢火焰离子化检测器(FID),柱温为程序升温。12种残留溶剂乙醇、异丙醇、丙酮、丁酮、乙酸乙酯、乙酸丁酯、乙酸正丙酯、甲苯、乙苯、对二甲苯、邻二甲苯、间二甲苯均能完全分离,在考察的浓度范围内线性关系良好(r>0.995),检出限分别为0.055,0.019,0.023,0.070,0.155,0.013,0.003,0.009,0.004,0.004,0.004,0.005μg/mL。平均回收率为90.6%~109.0%,测定结果的相对标准偏差为2.2%~5.6%(n=9)。该方法专属性强,精密度、准确度和检测灵敏度高,重复性好,可用于葡萄糖氯化钠注射液中12种溶剂残留量的测定。     

Pulse nebulization of chloroform and carbon tetrachloride extracts in flame atomic absorption spectrometry

The determination or cadmium, cobalt, copper, nickel and lead after extraction with tetramethylenedithiocarbamate into various solvents is achieved by injection of 50-μl aliquots of extract by pulse nebulization into an air-acetylene flame. The technique is particularly suitable for cadmium and lead extracted into chlorinated solvents, which must not continuously be nebulized into the flame. The performance of the technique is compared for chloroform, carbon tetrachloride, butyl acetate, methyl isobutyl ketone, toluene and xylene.     

Influence of the nature of organic phase emulsions on sensitivity in atomic-absorption determinations

The influence of the nature of organic phase emulsions on sensitivity in atomic-absorption determinations has been studied for the copper-APDC chelate extracted into various solvents. Oil-in-water emulsions containing 10% of organic phase emulsified with non-ionic and anionic surfactants were introduced into the flame and the atomic-absorption of copper was measured. An attempt was made to relate the effect on sensitivity to the physical properties of the different emulsions but no correlation was found. Rheological properties such as aspiration rate and nebulization efficiency did not differ significantly for different emulsified organic solvents. Enrichment of the waste solution proved the most important parameter for predicting an increase in sensitivity.     

Determination of chromium (III) using a homogenous mixture of water-ethanol-methylisobutylketone solvents

The use of organic solvents to increase metal ion determination sensitivity by atomic absorption spectrophotometry with flame is quite common. The most employed organic solvent is 4-methyl-2-pentanona (methylisobutylketone, MIBK) which optimizes sample vaporization and combustion. In this work, we present the use of a homogeneous mixture of water-ethanol—MIBK solvents (1:14:10 v/v, respectively), named the single-phase solution instead of employing pure organic solvents to determine chromium (III) ions by atomic absorption spectrophotometry with flame. The analytical calibration curve in single-phase solution evaluated up to 8 μg ml⁻¹ was linear and was described as Abs=0.0048 C_Cr(III)-0.0010 (r²=0.9998). Stability in the measurement as well as an increase in sensitivity more than twice as high when compared to determinations exclusively made in aqueous solutions were observed. The exactness of the determinations was evaluated with the same steel standards.     

Effect of some organic solvents and acids on the laser-induced atomic fluorescence of tin in air-hydrogen flames

The effects of some organic solvents and acids on the atomic fluorescence of tin in air-hydrogen flames have been examined. Ketones and alcohols greatly reduced the florescence sensitivity in fuel rich air-hydrogen flame whereas organic acids generally enhanced the fluorescence signal. The depressive effect of organic solvents was found to be highly dependent on the fuel to oxidant ratio in the flame. An attempt has been made to explain these effects, on the basis of possible reactions occurring in the flame.On leave from Institute of Chemistry, University of the Punjab, Lahore 54590, PakistanOn leave from Department of Analytical Chemistry, University of Zaragoza, Zaragoza, Spain     

顶空气相色谱法同时测定托比司他中的6种残留溶剂

采用顶空气相色谱技术,建立了同时测定托比司他中6种残留溶剂的方法。考察了不同固定相对分离效果的影响,优化了平衡加热时间影响以及制样溶剂。在优化的实验条件下,采用Rtx-200型聚三氟丙基甲基硅氧烷为固定相的色谱柱(30 m ×0.25 mm ×1μm)分离、氢火焰离子化检测器检测、外标法定量的分析方案,实现了甲醇、乙醇、二氯甲烷、乙酸乙酯、1,4-二氧六环和吡啶6种残留溶剂的同时分离与测定。6种溶剂在各自的线性范围内线性关系良好,线性相关系数( R2)均大于0.998,定量限分别为甲醇0.006%、乙醇0.005%、二氯甲烷0.012%、乙酸乙酯0.0025%、1,4-二氧六环0.0076%、吡啶0.004%。在3个添加水平下,6种残留溶剂的加标回收率在92.3%~100.3%之间,相对标准偏差为0.3%~3.6%。实际样品分析结果表明,本方法简单、快速、分离效果好,可用于托比司他中6种残留溶剂的检测。     

Effect of solvent extraction on the atomic-absorption spectrophotometry in determination of ppM levels of cadmium with dithizone

Various organic solvents for cadmium dithizonate extraction have been examined for their suitability for subsequent absorption spectrophotometry. The solvents are discussed on the basis of their physical properties. Much enhanced sensitivity is achieved by use of a large aqueous phase/solvent volume ratio. Conditions for the determination of ppM levels of cadmium are described for nitrobenzene and n-butyl acetate as solvents. Dithizone and cadmium dithizonate are very stable in nitrobenzene. The extraction is completely quantitative over the pH range 3.5-10.0. Interference by diverse ions was studied, and their tolerance levels are given.     

Spectroscopy in separated flames-IV: application of the nitrogen-separated air-acetylene flame in flame-emission and atomic-fluorescence spectroscopy

The primary and secondary combination zones of an air-acetylene flame have been separated by a stream of nitrogen flowing parallel to the flame to prevent access of atmospheric oxygen to its base. The flame is very stable over a wide range of fuel-air mixture strengths, and organic solvents may be aspirated without difficulty. The low flame background enables thermal-emission and atomic-fluorescence measurements to be made with high sensitivity. Bismuth, for example, has been determined in the range 5-200 ppm by its thermal emission at 306.8 nm, with a detection limit of 2 ppm in aqueous solution, and in the range 1-10 ppm with a detection limit of 0.3 ppm in 50% ethanolic solution. Zinc and cadmium have been determined at 213.9 nm and 228.8 nm by atomic-fluorescence spectroscopy in this flame with detection limits of 2 x 10(-4) ppm and 5 x 10(-4) ppm respectively, vapour-discharge lamps being used as sources of excitation. The results obtained represent a considerable improvement over those available by the same methods in a conventional air-acetylene flame.     

顶空气相色谱法测定三氯蔗糖中的有机溶剂残留

建立了顶空气相色谱法(HSGC)同时测定三氯蔗糖中甲醇、乙酸乙酯和乙酸丁酯残留量的分析方法。用Angilent Innowax毛细柱,程序升温,FID检测器,以保留时间定性,外标法定量,探讨了盐溶液、相比、平衡温度、平衡时间和振荡幅度等因素对测定结果的影响。结果表明,以100 g/L NaCl溶液为溶解液,取1mL溶液于20 mL顶空瓶中,平衡温度为80℃,平衡时间为15 min,振荡幅度低的条件下,该方法线性关系良好,3种物质线性方程的相关系数r在0.9999~1之间;方法精密度RSD(n=6)小于2.0%。三氯蔗糖样品的加标平均回收率均在95%以上。     

顶空气相色谱法同时测定人工牛黄中7种残留溶剂

建立了同时测定人工牛黄中石油醚（60~90 ℃）、丙酮、乙酸乙酯、甲醇、二氯甲烷、乙醇、乙酸丁酯7种残留溶剂的顶空气相色谱分析方法。以Agilent DB-WAX毛细管色谱柱为分离柱,氢火焰离子化检测器检测,内标法定量,并考察了顶空平衡温度、加压时间、平衡时间等对残留溶剂测定的影响。在优化的条件下,7种残留溶剂在选择的浓度范围内线性关系良好,相关系数（r）均不小于0.9993;在高、中、低3个加标水平下,平均回收率为94.7%~105.2%,相对标准偏差（RSD）均不大于3.5%。方法的检出限（LOD）为0.43~5.23 mg/L,定量限（LOQ）为1.25~16.67 mg/L。该方法操作简单、准确灵敏、高效快捷,适用于人工牛黄中7种残留溶剂的同时检测。     

顶空-气相色谱法测定醋氯芬酸中的残留溶剂

建立了采用顶空-气相色谱法(HS-GC)测定醋氯芬酸中残留溶剂的方法.试验条件:以DB-624(30 m×0.32 mm,1.8μm)为色谱柱,使用氢火焰离子化检测器(FID),柱温为程序升温,顶空平衡温度80℃,平衡时间30 min.结果表明,异丁烯、甲醇、乙酸甲酯和叔丁醇可有效分离,检测限分别为0.013、0.72...     

原子吸收光谱法测定三醋酸纤维素膜中铜铁

运用空气-乙炔火焰原子吸收光谱法同时测定银锌电池三醋酸纤维素膜中铜铁含量,并对测定条件和干扰因素进行了综合分析.该测定方法具有很好的灵敏度,干扰少,选择性和重现性好等优点.测定样品铜铁含量的相对标准偏差均小于1.0%.标准加入回收率均在97.3%～98.8%范围内.完全适用于银锌电池三醋酸纤维素膜中铜铁含量的控制和样品系统分析.     

Development of a residual solvent test for bulk alpha-phenyl-1-(2-phenylethyl)-piperine methanol using headspace sampling

An automated static headspace gas chromatographic method for the determination of residual solvents in the bulk drug substance alpha-phenyl-1-(2-phenylethyl)-piperine methanol, a serotonin 5-HT2 receptor antagonist, is evaluated. The method includes the use of 1-propanol as an internal standard. The gas chromatographic conditions utilize a dimethylpolysiloxane phase (SPB-1) capillary column and a flame ionization detector. Validation of this test method includes a recovery study of known levels of acetone, ethyl acetate, methanol, and methyl ethyl ketone in the range of 0.05% to 1.0% (weight-per-weight or w/w) to verify the accuracy of this method; these four solvents are the most likely residual volatiles used in the production of the drug substance. These data and other aspects of the development of this test method are discussed.     

Rapid analysis of sorbitol, galactitol, mannitol and myoinositol mixtures from biological sources

The three commonly found hexitols mannitol, sorbitol and galactitol are well separated from each other and from myoinositol by gas chromatography as their butylboronate derivative on Dexsil-400, on a 1:1 mixture of OV-1 and OV-17, or on a DB-17 fused-silica capillary column. The method allows all four substances to be measured by autosampling electron ionization gas chromatography-mass spectrometry (GC-MS) in small tissue samples at organ concentrations as small as 5 mumol/kg wet mass in less than 4 min. Comparisons were made to determine the relative sensitivity of GC-MS and other detection methods. The order of sensitivity was electron ionization GC-MS greater than chemical ionization GC-MS greater than flame photometric detection using a boron-selective filter greater than hydrogen flame ionization detection.     

Determination of nickel in the serum of occupationally exposed workers, by means of flame atomic-absorption spectroscopy

A flame atomic-absorption spectroscopy method for determination of nickel in the serum of occupationally exposed subjects has been developed. Trichloroacetic add is utilized for precipitating proteins and freeing bound nickel; sodium diethyldithiocarbamate is used as complexing agent and isopropyl acetate as the solvent for extraction. The method is characterized by good accuracy, precision and sensitivity, over a concentration range up to about 20 ng/ml. Calcium, which is present in serum in great excess with respect to typical nickel concentrations, does not interfere in the determination of the latter.     

Use of Adsorbents for Recovery of Acetic Acid from Aqueous Solutions Part III—Solvent Regeneration

Solvent leaching was investigated as a method of regeneration for activated carbons and polymer sorbents loaded with acetic acid by contact with aqueous solutions. Both batch-equilibration and fixed-bed experiments were employed. Methanol, methyl acetate, and acetone are suitable regeneration solvents for most activated carbons. Amoco GX-031 is an exception, giving incomplete regeneration. Methanol provides still more efficient regeneration for macroreticular styrene-divinylbenzenes adsorbents. Among basic sorbents, amine resins give incomplete regeneration by solvent leaching, as does a poly N oxide. Polybenzimidazole, a weaker base, gives higher recoveries of acetic acid when leached by solvents. Poly(4-vinylpyridine) is regenerated completely and efficiently by methanol, methyl acetate, and acetone in a fixed-bed geometry. It thus appears that an intermediate degree of basicity is desirable in a synthetic sorbent for acetic acid – strong enough to give the uptake benefits of acid-base interactions, but weak enough to be regenerable.     

Method for calibrating olfactometer output. Part 2. Amyl acetate

A method for measuring amyl acetate in air was developed and validated. Known volumes of air samples from the output of an olfactometer, a device used to generate odor stimuli, were passed through charcoal sorbent tubes. Following extraction of the sorbent with carbon disulfide, the amount of amyl acetate collected on each tube was determined by gas chromatography with flame ionization detection. The method was used to determine the actual concentrations of amyl acetate presented to experimental participants in odor sensitivity testing.     

Atomic fluorescence spectroscopy of beryllium

The atomic fluorescence of beryllium has been observed. A high-intensity beryllium hollow-cathode lamp was used as the source. Oxy-acetylene and nitrous oxide-acetylene flames were studied. A newly designed burner assembly for nitrous oxide-acetylene flames used for atomic fluorescence studies is described. The sensitivity for beryllium at 2349 Å was 10 p.p.m. in the oxy-acetylene flame and 0.5 p.p.m. in the nitrous oxide-acetylene flame. The analytical calibration curves for both flames are presented. No significant interference was found from the cations studied. Some anionic interferences were removed by EDTA. The effects of some organic solvents were investigated.     

Microextraction of volatile compounds from wine samples and their determination by GC-FID. The effect of the salts and extraction solvents used

Summary This study describes the optimization of microextraction as a method for extracting volatile compounds from wine. The study has been applied to twelve compounds present in wine: 3-methylbutyl acetate, 3-methyl-1-butanol, ethyl hexanoate, hexanol, ethyl octanoate, butanoic acid, ethyl decanoate, diethyl succinate, hexanoic acid, phenylethanol, octanoic acid, and decanoic acid. These compounds were selected from those identified by GC-MS analysis of a real wine sample. By means of a synthetic wine, the study investigated the influence on extraction yield of the solvents and salts used, the proportion of salts, and the agitation time. The determination was performed by GC with flame ionization detection and an internal standard was used for quantification. The method was applied to samples of white wine from La Rioja.     

Comparison of atomic fluorescence power efficiencies for the helium-oxygen-acetylene and air-acetylene flames

Power efficiencies for five elements have been measured for the helium-oxygen-acetylene and air-acetylene flames. The increased power efficiencies found in this study for the helium-diluted flame, coupled with its enhanced atom-formation capabilities, suggest that lower atomic fluorescence detection limits should exist. However, in a comparison study with an air-acetylene flame using identical experimental conditions, a decreased atomic fluorescence signal-to-noise ratio was found for most elements in the helium-diluted flame. This decrease is ascribed to greater background emission noise in the hotter helium-diluted flame and decreased nebulization efficiency caused by the low density of the helium-containing nebulizer gas. A comparison of flame emission detection limits for the two flames confirms the increased sensitivity of the hotter helium-oxygen-acetylene flame, despite its lower nebulization efficiency.