High Pressure Liquid Chromatography of (Bay o 9867) Ciprofloxacin in Serum Samples

Abstract

Quantitative analysis of ciprofloxacin using liquid chromatography and a traditional microbiological assay were compared and had a correlation coefficient of 0.9701. Liquid chromatography (LC) was a modification of that of Wingender et al. (1) and used a mobile phase consisting of water, acetonitrile, phosphoric acid, and tetrabutylammonium hydroxide. Separation on a reverse phase C18 column gave a retention time of 3.6 minutes.     

Fluorometric Determination of Histamine in Biological Fluids and Tissue by High-Performance Liquid Chromatography

Abstract

High-pressure liquid chromatography was used to separate the fluorescent adduct formed from the reaction of histamine with o-phthalaldehyde (OPT) from other biogenic amines in tissue, cerebrospinal fluid (CSF), sweat and urine samples. Using off-column derivatization and isocratic elution techniques fluorescent OPT adducts can be detected in the low picogram range. Perchloric acid extracts of tissue samples from Aplysia california and urine specimens collected from healthy adult males, including internal standard, were derivatized with OPT buffer, pH 9.5 and extracted with ethylacetate to increase sensitivity and stabilization of the fluorescent adduct prior to chromatography. Sweat and CSF samples were reacted with OPT buffer and aliquots of this mixture injected directly onto the chromatographic column (μBondapak CN) with methanol/0.08 mol/liter acetic acid (52/48 by volume) as the mobile phase. Assay of pooled urine containing added histamine (1 μg/ml) gave a with-in run coefficient of variation of 2.5%. The use of o-phthalaldehyde as an off-column HPLC derivatization agent for fluorometric determination of low-levels of biogenic amines is rapid, sensitive and easily adapted to routine use in a clinical or neurobiological laboratory.     

Rapid Assay for the Determination of Tolfenamic Acid in Pharmaceutical Preparations and Biological Fluids by High-Performance Liquid Chromatography

Abstract

An improved reversed-phase High-Performance Liquid Chromatographic (HPLC) method using UV detection, at 282 nm, is described for the determination of tolfenamic acid in the presence of caffeine, as internal standard, in pharmaceutical preparations and biological fluids. Sample analyses are performed with a Lichrosorb-RP18, 10 μm, 250×4 mmLD., column using acetate buffer, (pH 4.6 and constant ionic strength 0.05 M) methanol (18:82) as eluent, at a flow rate of 1.9 ml/min. The retention time is 1.44 min for caffeine and 2.62 min for tolfenamic acid. The absolute detection limit is 0.5 ng in the presence and 0.9 ng in the absence of internal standard and linearity is observed up to 100 ng injected. The method involves the use of solid     

Tocainide Determination by High-Performance Liquid Chromatography

Abstract

Tocainide has been assayed after serum deproteinization with acetonitrile by HPLC. The pH was critical in separating the drug from other interferences in the serum. The method is simple and fast.     

The Rapid Determination of Neutral Sugars in Biological Samples by High-Performance Liquid Chromatography

Abstract

A procedure for the analysis of neutral sugars in biological specimens is described. The method entails acid hydrolysis of the sample to liberate monosaccharides, which are subsequently derivatized with dansyl hydrazine. The sugar-dansyl hydrazones are separated and quantitated by hplc on a 5μ C18 RadialPak column with a gradient of acetonitrile in 10mM ammonium sulfate at pH 7. Fluorescent detection of the derivatized sugars permits 100-fold increased sensitivity compared to previously published glc methods.

This procedure was applied to the neutral sugar analysis of a glycoprotein of known composition (thyroglobulin) and to hard keratin fibers. The latter substance served as a model to critically evaluate the method on a highly resistant biological matrix containing low concentrations of neutral sugars.     

The Analysis of Penicillins in Biological Fluids and Pharmaceutical Preparations by High-Performance Liquid Chromatography: A Review

Abstract

High performance liquid chromatographic methods for the analysis of penicillins in biological fluids and pharmaceutical preparations are reviewed. In particular, sample preparation and handling procedures, chromatographic conditions and detection methods are discussed. A summary of published high performance liquid chromatographic assays for individual penicillins is included.     

Determination of Monobromobimane-Labeled Phytochelatins by High-Performance Liquid Chromatography

A new method for phytochelatins by high-performance liquid chromatography (HPLC) was developed based on a condensation reaction with monobromobimane to produce fluorescent derivatives. Glutathione, H-(γ-glutamic acid-cysteine)₂-glycine-OH, H-(γ-glutamic acid-cysteine)₃-glycine-OH, H-(γ-glutamic acid-cysteine)₄-glycine-OH, H-(γ-glutamic acid-cysteine)₅-glycine-OH, and H-(γ-glutamic acid-cysteine)₆-glycine-OH were well separated, with retention times between 14.68 and 22.0 min. The HPLC method had good linearity (r < 0.9991) between 0.1 mg L^?1 and 100 mg L^?1. The limits of quantification for the analytes (S/N = 3) were 0.08, 0.3, 0.05, 0.3, 0.5, and 0.8 mg L^?1, respectively. The recoveries were between 83.0% and 101.33% with relative standard deviations less than 2%. The reported method is simple, accurate, and suitable for the determination of phytochelatins.     

Determination of Carbonyl Compounds by High-Performance Liquid Chromatography

Carbonyl compounds in the form of 2,4-dinitrophenylhydrazones in alcoholic solutions were analyzed by high-performance liquid chromatography. This simple procedure is characterized by high sensitivity and reproducibility.     

高效液相色谱法测定环己铜过氧化物

以甲醇或甲醇与水作流动相,ODS为固定相,测定环己酮的多种过氧化物。平均回收率100.2％～101.6％,测定的相对标准偏差为1.02％～2.51％。     

Determination of Dialkyltin Compounds in Poly(Vinyl Chloride) by High-Performance Liquid Chromatography

A high-performance liquid chromatography (HPLC) method has been developed for the analysis of dialkyltin compounds in polyvinyl chloride (PVC) materials. The PVC sample was first dissolved in tetrahydrofuran. Concentrated hydrochloric acid was then added to convert the dissolved dialkyltin stabilizers into the chloride forms, followed by extraction with hexane. The extracted dialkyltin chlorides were preconcentrated and were finally separated by HPLC. Separation was performed using a C₁₈ column and an eluent of aqueous methanol containing 8-hydroxyquinoline (oxine) as the completing agent. Photometric detection of the dialkyltin-oxine complexes was carried out at 380 mm. Under optimum experimental conditions, the detection limits for dimethyltin, dibutyltin and dioctyltin are 1.7 ng, 2.1 ng and 2.9 ng (all as tin), respectively. Residual dialkyltin stabilizers in several commercially available PVC products were successfully analyzed via this method.     

Determination of Flurbiprofen in Dosage form and in Biological Fluids by High Performance Liquid Chromatography

Abstract

A high performance liquid chromatograpy method is described for the determination of flurbiprofen in both dosage form and in biological fluids (urine and plasma) using fluorescence detection. The method for dosage forms involves grinding of a 100 mg tablet, suspension in methanol, filtration and adjusting to the appropriate concentration and 10 ul is injected onto the column. In the case of biological fluids a series of standard solutions were prepared in 0.IN sodium hydroxide and a known amount was added to 1 ml of serum or urine which was then acidified, extracted with ethylacetate, evaporated and the residue was then dissolved in a known volume of the mobile phase. Complete separation of the drug was achieved in about 6.5 minutes under the used conditions.     

Simultaneous Determination of Food-Related Amines by High-Performance Liquid Chromatography

Abstract

Ten amines found in marine foods, dimethylamine, trimethylamine, trimethylamine oxide, ammonia, urea, histamine, cadaverine, putrescine, spermine and spermidine were separated by HPLC using an ion-moderated partition column. Optimum resolution and sensitivity were obtained using 0.003N sodium hydroxide as the mobile phase and UV detection at 208 nm.     

高效液相色谱法测定血清中茶碱浓度

采用高效液相色谱,分析柱：３μｍ,３．３ｃｍ＊４．６ｍｍ,Ｉ．Ｄ（Ｐｅｒｋｉｎ Ｅｌｍｅｒ,ＵＳＡ）;预柱：１０μｍ,１ｃｍ＊２．１ｍｍ,Ｉ．Ｄ（Ｐｅｒｋｉｎ ＥＬｍｅｒ,ＵＳＡ）;以乙酰氨基酚为内标对氯仿－异丙醇（９５：５,Ｖ／Ｖ）提取样品进行了分析,流动相：０．１ｍｏｌ／Ｌ醋酸缓冲液（ＰＨ＝４．５）－甲醇（７０：３０,Ｖ／Ｖ）;检测波长：２７０ｎｍ;流速０．５ｍＬ／ｍｉｎ,３ｍｉｎ即完成一次茶     

Determination of Pyridostigmine in Human Plasma by High-Performance Liquid Chromatography

Abstract

An easy to perform, specific, reproducible and sensitive high performance liquid chromatographic (HPLC) method to measure pyridostigmine concentration in human plasma was developed and validated. Sample clean-up consists of ion-pair extraction into dichloromethane in the presence of neostigmine as internal standard, followed by back extraction into an aqueous phase. Mean recovery of 110% (with a standard deviation of 10%) was determined for concentrations of 5 – 100 ng/ml. Chromatography on a 125·4 mm CN-propyl column using a mobile phase composed of 10% acetonitrile in 3.5×10^?4M NaH₂PO₄ and UV detection at 270 nm, yields clean chromatograms without any interferences from endogenous plasma components. Using 1 ml plasma samples the method has a limit of detection (LD) of 3 ng/ml, with %CV (precision) and bias (accuracy) ≥ 10% for concentrations in the range of 0–100 ng/ml. The method is being used in human pharmacokinetic studies of oral dosage forms of pyridostigmine.     

Determination of Cefpirome in Human Plasma by High-Performance Liquid Chromatography

Abstract

Cefpirome is an investigational third-generation cephalosporin, which appears promising for the treatment of various pediatric infections. A high performance liquid chromatographic method was developed to measure cefpirome in small volumes of plasma for conducting pharmacokinetics studies in infants and children. the assay involved precipitation of plasma proteins with acetonitrile, using cefaclor as an internal standard. Chromatographic separation was accomplished using a reverse-phase     

Analysis of Cimetidine in Biological Fluids by High Performance Liquid Chromatography

Abstract

The clean-up and analysis of cimetidine in human urine and blood is described. Samples were prepared by adsorption on Waters Sep-pak C-18 disposable pre-columns in basic solution followed by elution in 1 ml methanol. For blood samples, the eluate was concentrated under a stream of nitrogen; urine samples required no further concentration. The separation was performed on a reversed phase column using a mixture of methanol-1 mM sodium dodecyl sulphate in a 10 mM phosphate buffer of pH 3.0 (35:65) as mobile phase. Procaine was used as internal standard. Detection was by UV at 228 nm yielding a minimum detectable quantity of 20 ng with linearity over three decades of concentration.     

Determination of Acyclovir in Human Serum by High-Performance Liquid Chromatography

Abstract

A method was developed for determination of concentrations of acyclovir in serum. Serum proteins were precipitated with equal part of 5% perchloric acid. High-performance liquid chromatography was used for separation from endogenous compounds and detection was done with spectrophotometry. The assay is simple and precise and seems well suited for pharmacokinetic studies.     

高效液相色谱法测定肉制品中甘草抗氧化物的含量

建立了测定肉制品中甘草抗氧化物含量的方法。样品经流动相提取,采用C．8色谱柱分离,以甲醇-0．2mol／L乙酸铵-冰乙酸（体积比70：29：1）为流动相,流速为1．0mL／min,波长为250nm,以保留时间进行定性,峰面积进行定量。甘草酸在1．0-80．0μg／mL范围内线性关系良好,回归方程为y=8．55×10^-5x-0．599（r=0．9997）,检出限为1．0mg／kg,定量限为3．0mg／kg,加标回收率为95．7％-103．4％,测定结果的相对标准偏差为1．57％-3．53％（n=6）。该方法适用于检验机构日常检验中大批量肉制品中甘草抗氧化物含量的测定。     

高效液相色谱法测定有机肥中洛克沙胂

建立了高效液相色谱(HPLC)-串联紫外检测法检测有机肥中洛克沙胂的分析方法。选用20g·L-1K2HPO4作为提取剂,于60℃温度下超声提取有机肥中的洛克沙胂,采用MAX固相萃取柱净化。结果表明,采用Symmetry ShieldTMRP 18色谱柱,以含0.1%甲酸的0.05mol·L-1 KH2PO4∶甲醇=95∶5(V/V)溶液作流动相,等度洗脱,紫外266nm检测,洛克沙胂的保留时间短,且可完全避开杂质峰的干扰;其平均加标回收率介于81.14%~82.75%之间,相对标准偏差(RSD)7.0%,检出限为20μg·L-1。方法重现性好,精密度高,操作简便,适用于有机肥中洛克沙胂检测。