Flow-injection chemiluminescence determination of ofloxacin and levofloxacin in pharmaceutical preparations and biological fluids.

A novel, rapid and sensitive analytical method is described for determination of ofloxacin and levofloxacin by enhanced chemiluminescence (CL) with flow-injection sampling. The method is based on the CL reaction of the Ce(IV)-Na2S2O4-ofloxacin/levofloxacin-H2SO2 system. The enhanced CL mechanism was developed and the optimum conditions for CL emission were investigated. The CL intensity was correlated linearly (r = 0.9988) with the concentration of ofloxacin (or levofloxacin) in the range of 1.0 x 10(-8) - 1.0 x 10(-7) g ml(-1) and 1.0 x 10(-7) - 6.0 x 10(-6) g ml(-1). The detection limit (S/N = 3) is 7 x 10(-9) g ml(-1). The relative standard derivation (RSD, n = 11) is 2.0% for ofloxacin at 4 x 10(-7) g ml(-1) and for levofloxacin at 6 x 10(-7) g ml(-1). This method has been successfully applied for the determination of ofloxacin and levofloxacin in pharmaceutical preparations and biological fluids with satisfactory results.     

Investigating the post-chemiluminescence behavior of phenothiazine medications in the luminol–potassium ferricyanide system: molecular imprinting–post-chemiluminescence method for the determination of chlorpromazine hydrochloride

A new post-chemiluminescence (PCL) phenomenon was observed when phenothiazine medications were injected into the reaction mixture after the chemiluminescence (CL) reaction of luminol and potassium ferricyanide had finished. A possible reaction mechanism was proposed based on studies of the kinetic characteristics of the CL, CL spectra, fluorescence spectra, and on other experiments. The feasibility of determining various phenothiazine medications by utilizing these PCL reactions was examined. A molecular imprinting–post-chemiluminescence (MI-PCL) method was established for the determination of chlorpromazine hydrochloride using a chlorpromazine hydrochloride-imprinted polymer (MIP) as the recognition material. The method displayed high selectivity and high sensitivity. The linear range of the method was 1.0×10⁻⁸∼1.0×10⁻⁶, with a linear correlation coefficient of 0.9985. The detection limit was 3×10⁻⁹ g/ml chlorpromazine hydrochloride, and the relative standard deviation for a 1.0×10⁻⁷ g/ml chlorpromazine hydrochloride solution was 4.0% (n=11). The method has been applied to the determination of chlorpromazine hydrochloride in urine and animal drinking water with satisfactory results.      

Flow-injection chemiluminometric determination of some thioxanthene derivatives in pharmaceutical formulations and biological fluids using the [Ru(dipy)3(2+)]-Ce(IV) system.

A flow-injection (FI) methodology using tris(2,2'-dipyridyl)ruthenium(II), [Ru(dipy)3(2+)], chemiluminescence (CL) was developed for the rapid and sensitive determination of three thioxanthene derivatives, namely zuclopenthixol hydrochloride, flupentixol hydrochloride and thiothixene. The method is based on the CL reaction of the studied thioxanthenes with [Ru(dipy)3(2+)] and Ce(IV) in a sulfuric acid medium. Under the optimum conditions, calibration graphs were obtained over the concentration ranges 0.002-6 migrograms/ml for zuclopenthixol hydrochloride, 0.5-15 micrograms/ml for flupentixol hydrochloride and 0.05-7.5 micrograms/ml for thiothixene. The limits of detection (s/n = 3) were 4.2 x 10(-9) mol/l zuclopenthixol hydrochloride, 2 x 10(-8) mol/l flupentixol hydrochloride and 4.5 x 10(-8) mol/l thiothixene. The method was successfully applied to the determination of these compounds in dosage forms and biological fluids.     

Chemiluminescence determination of some fluoroquinolone derivatives in pharmaceutical formulations and biological fluids using [Ru(bipy)(3)(2+)]-Ce(IV) system

A new chemiluminescence (CL) method using flow injection has been described for the rapid and sensitive determination of three fluoroquinolone derivatives, namely ofloxacin, norfloxacin and ciprofloxacin hydrochloride. The method is based on the CL reaction of the studied fluoroquinolones with tris(2,2'-bipyridyl)ruthenium(II) [Ru(bipy)(3)(2+)] and Ce(IV) in sulfuric acid medium. Under the optimum conditions, the CL intensity is proportional to the concentration of the drugs in solution over the range 0.05-7.0 mug ml(-1) for norfloxacin, 0.05-6.0 mug ml(-1) for ciprofloxacin hydrochloride and 0.003-0.7 mug ml(-1) for ofloxacin. The limits of detection (s/n=3) were 3.1x10(-8) M norfloxacin, 2.6x10(-8) M ciprofloxacin hydrochloride and 5.5x10(-9) M ofloxacin. The method was applied successfully to the determination of these compounds in dosage forms and biological fluids.     

Sensitive determination of phenothiazines in pharmaceutical preparation and biological fluid by flow injection chemiluminescence method using luminol-KMnO4 system

A flow injection chemiluminescence method was described for the determination of four phenothiazine drugs, namely, chlorpromazine hydrochloride, perphenazine hydrochloride, fluphenazine hydrochloride and thioridazine hydrochloride. Strong Chemiluminescence (CL) signal was produced when above-mentioned drug was injected into the mixed stream of luminol with KMnO₄. The linear ranges of the method were 0.0020-1.0 μg/mL chlorpromazine hydrochloride, 0.0040-3.0 μg/mL perphenazine hydrochloride, 0.0020-5.0 μg/mL fluphenazine hydrochloride and 0.0050-1.0 μg/mL thioridazine hydrochloride. The detection limits were 0.4 ng/mL chlorpromazine hydrochloride, 0.7 ng/mL perphenazine hydrochloride, 2 ng/mL fluphenazine hydrochloride and 0.7 ng/mL thioridazine hydrochloride. The proposed method was applied to the determination of chlorpromazine hydrochloride in injections and in mental patient's urine samples and the satisfactory results were achieved. The possible CL reaction mechanism was also discussed briefly.     

Post-chemiluminescence phenomenon of NBS-luminol reactions and their applications to flow injection analysis of piroxicam.

A new post-chemiluminescence (PCL) reaction was observed when piroxicam was injected into the reaction mixture after the CL reaction of N-bromosuccinimide (NBS) and luminol. A possible reaction mechanism was proposed based on the studies of the CL kinetic characteristics, the CL spectra, fluorescence spectra and other experiments. A new flow injection CL method for the determination of piroxicam was established based on the PCL reaction. The relative standard deviation (RSD) for the determination of piroxicam was 1.2% (n = 11, c = 2.0 x 10(-6) g/ml). The CL intensity responded linearly to the concentration of piroxicam in the range 1.0 x 10(-7) - 1.0 x 10(-5) g/ml (r = 0.9991). The detection limit was 4.0 x 10(-8) g/ml. The method had been applied to the determination of piroxicam in tablets with satisfactory results.     

Flow injection with inhibited chemiluminescence method for the determination of dopamine hydrochloride.

A simple rapid and accurate flow injection inhibitory chemiluminescence method has been developed for the determination of dopamine hydrochloride based on its inhibition of the chemiluminescence from the luminol-potassium hexacyanoferrate(III) system. The linear range of determination is 4.0 x 10(-9) - 4.0 x 10(-7) g ml(-1) for dopamine hydrochloride and the detection limit is 1.14 x 10(-9) g ml(-1). The method has been applied to determine the content of dopamine in pharmaceutical preparation with satisfactory results.     

Molecular imprinting-chemiluminescence determination of trimethoprim using trimethoprim-imprinted polymer as recognition material

A new molecular imprinting-chemiluminescence method for the determination of trimethoprim was developed, in which trimethoprim-imprinted polymer was used as the molecular recognition material and the CL reaction of trimethoprim with potassium permanganate in acidic medium was used as the detection system. The CL intensity responds linearly to the concentration of trimethoprim within the 5.0 x 10(-8)-5.0 x 10(-6) g mL(-1) range (r= 0.9983) with a detection limit of 2 x 10(-8) g mL(-1). The relative standard deviation for the determination of 1.0 x 10(-7) g mL(-1) trimethoprim solutions is 4.8% (n= 9). The method has been applied to the determination of trimethoprim in pharmaceutical preparations and body fluids, and satisfactory results were obtained.     

N-bromosuccinimide-fluorescein based sensitive flow-injection chemiluminescence determination of phenformin.

A novel and highly sensitive method for the determination of phenformin over the range of 6 x 10(-9) - 1 x 10(-5) g ml(-1) in pharmaceutical formulations with flow-injection chemiluminescence (CL) detection is proposed. The method is based on the CL produced during the oxidation of N-bromosuccinimide (NBS) in an alkaline medium in the presence of fluorescein as an effective energy transfer agent. The use of cetyltrimethylammonium bromide (CTAB) as a sensitizer enhances the signal magnitude by about 100 times. The detection limit is 2 x 10(-9) g ml(-1) (3sigma) with a relative standard deviation of 2.3% (n = 11) at 1 x 10(-7) g ml(-1) phenformin. Ninety samples can be determined per hour. The method was evaluated by carrying out a recovery study and by the analysis of commercial formulations. The obtained results compared well with those by an official method, and demonstrated good accuracy and precision. The possible CL mechanism of the proposed system was also briefly analyzed.     

Chemiluminescence sensor for the determination of perphenazine based on a molecular imprinted polymer.

A luminol-potassium ferricyanide-perphenazine CL reaction with high sensitivity for the determination of perphenazine was found. A perphenazine molecular imprinted polymer (MIP) was synthesized. Using the perphenazine MIP as a recognition material, a novel molecular imprinting-chemiluminescence (MI-CL) sensor for the determination of perphenazine was made based on the luminol-potassium ferricyanide-perphenazine CL reaction. The sensor displayed good selectivity and high sensitivity. The linear-response range of the sensor was 5.0 x 10(-8) - 1.0 x 10(-5) g/ml with a linear correlation coefficient of 0.9961. The detection limit was 2 x 10(-8) g/ml perphenazine and the relative standard deviation for 1.0 x 10(-6) g/ml perphenazine solution was 3.7% (n = 11). The sensor was applied to the determination of perphenazine in urine samples with satisfactory results.     

Sensitive assay for catecholamines in pharmaceutical samples and blood plasma using flow injection chemiluminescence analysis.

A rapid and sensitive chemiluminescence (CL) method using flow injection analysis was described for the determination of three catecholamines: dopamine, adrenaline and dobutamine, based on their greatly enhancing effects on the CL reaction of luminol-potassium periodate in basic solutions. Under the optimized conditions, the calibration graphs relating the increase of CL intensity to the concentration of the analytes were linear. The present method allows for the determination of dopamine, adrenaline, and dobutamine over the range of 1.0 x 10(-10) - 1.0 x 10(-7) g/ml. The relative standard deviations for measurements (n=11) of dopamine, adrenaline and dobutamine were 2.9, 2.3 and 1.8% when the concentrations of three catecholamines were at 1.0 x 10(-9) g/ml, respectively. The detection limits of the method were 2.0 x 10(-11) g/ml dopamine, 1.0 x 10(-11) g/ml adrenaline and 4.0 x 10(-11) g/ml dobutamine. The method was successfully applied to the determination of three catecholamines in pharmaceutical samples and blood plasma.     

Flow injection chemiluminescence determination of hydrazine by oxidation with chlorinated isocyanurates

A rapid and sensitive flow injection chemiluminescence (CL) method is described for the determination of hydrazine based on the CL generated during its reaction with either sodium dichloroisocyanurate (SDCC) or trichloroisocyanuric acid (TCCA) in alkaline medium. The emission intensity is greatly enhanced if dichlorofluorescein (DCF) as sensitizer is present in the reaction medium. The presence of citrate prevents the precipitation of some cations in the reaction medium and also causes an enhancement in emission intensity. The effect of analytical and flow injection variables on these CL systems and determination of hydrazine are discussed. The optimum parameters for the determination of hydrazine were studied and were found to be the following: SDCC and TCCA both 1x10(-3) M; NaOH, 2x10(-1) M; DCF, 5x10(-6) M; citrate, 1x10(-3) M and flow rate, 3.8 ml min(-1). The optimized method yielded 3sigma detection limits of 2x10(-7) and 3x10(-7) M for hydrazine with SDCC and TCCA oxidants, respectively. The method is simple, fast, sensitive, and precise and was applied to the determination of hydrazine in water samples.     

多壁碳纳米管修饰电极检测盐酸氯丙嗪的研究

制备了多壁碳纳米管修饰玻碳电极,采用循环伏安法(CV)研究了盐酸氯丙嗪在修饰电极上的电化学特性,发展了一种新的检测盐酸氯丙嗪的电化学分析方法。在最佳实验条件下,用循环伏安法检测盐酸氯丙嗪,其响应电流与盐酸氯丙嗪的浓度在8.0×10-5~1.0×10-3mol/L范围内有很好的线性关系,线性方程为Ip(A)=0.0106c(mol/L)-8×10-8(R2=0.999,n=6),检出限为6.2×10-6mol/L(S/N=3)。方法可用于盐酸氯丙嗪片的测定。     

Determination of trace aluminum (III) using a novel cerium (IV)-calcein chemiluminescence detection

A simple, sensitive and selective chemiluminescence (CL) method was developed for the direct determination of aluminum (Al). This method is based on that the weak CL of cerium (IV)-calcein can be greatly enhanced by Al(III). The calibration curve was linear over the range 2.0 x 10(-10) to 4.0 x 10(-8)g mL(-1) with a detection limit of 8 x 10(-11)g mL(-1) (3sigma). The R.S.D. was 2.5% by 11 replicated determinations of 1.0 x 10(-9)g mL(-1) Al(III). The proposed method has been used to determine the concentration of Al(III) in real water samples with satisfactory results. The mechanism of the CL reaction was also discussed.     

盐酸氯丙嗪与Fe(Ⅲ)的显色反应及测定

研究了在盐酸介质中,三价铁离子能将盐酸氯丙嗪氧化成一种红色的物质,且氧化的程度与盐酸氯丙嗪的量呈正比关系,据此建立了测定盐酸氯丙嗪的分光光度分析方法。实验中最大吸收波长为530nm,摩尔吸光系数为5.13×103 L/(mol·cm),盐酸氯丙嗪的量在5~250μg/10mL范围内与吸光度A有良好的线性关系,方法用于盐酸氯丙嗪药物的测定,其相对标准偏差为0.11%~0.19%,加标回收率为95.0%~97.0%。     

Voltammetric determination of chlorpromazine hydrochloride

The electrochemical behaviour of chlorpromazine hydrochloride (CPZ-HCI) in sulphuric acid was investigated voltammetrically using ruthenium electrodes and it was subsequently determined by the same method. From the recorded voltammograms it was concluded that CPZ-HCI can be determined in the concentration range 2 x 10(-4)-8 x 10(-4) M (71-284. 3 micrograms ml-1). The proposed voltammetric method was applied to the determination of CPZ-HCI in tablets used for neuroleptic purposes in Turkey; the amount of effective compound was found to be within the ranges given for a pharmacopoeial procedure.     

Determination of riboflavin by enhancing the chemiluminescence intensity of peroxomonosulfate-cobalt(II) system

A weak chemiluminescent (CL) emission was observed in the decomposition of peroxomonosulfate (HSO5-), which would be accelerated in the presence of trace amounts of cobalt (II). The mechanism was due to the production of singlet oxygen (1O2). Interestedly, riboflavin can enhance the CL and the CL intensity was strongly dependent on riboflavin concentration. Based on this phenomenon, a flow injection analysis (FIA) CL method was established for the determination of riboflavin. Additionally, the possible CL mechanism is proposed based on the kinetic curve of the CL reaction, CL spectra, UV-vis spectra and fluorescent spectra. The CL intensity was correlated linearly with concentration of riboflavin over the range of 1.0x10(-4) to 1.0x10(-8) g mL-1; the detection limit was 9.0x10(-9) g mL-1(S/N=3); the relative standard deviation was 1.4% for 9x10(-7) g mL-1 riboflavin (n=11). Furthermore, this method was applied to the determination of riboflavin in real tablets and injections successfully.     

流动注射后化学发光法测定盐酸阿比朵尔

研究了盐酸阿比朵尔在鲁米诺-K3Fe(CN)6化学发光反应体系中的后化学发光反应. 据此建立了测定盐酸阿比朵尔的流动注射后化学发光分析法. 方法的线性范围为6.0×10-9～1.0×10-7 g/mL, 检出限(3σ)为2×10-9 g/mL. 对4.0×10-8 g/mL的盐酸阿比朵尔溶液连续11次平行测定, RSD=1.3%. 方法已用于盐酸阿比朵尔胶囊及尿样中盐酸阿比朵尔含量的测定. 在对这一后化学发光反应的动力学性质、化学发光光谱、紫外可见吸收光谱以及一些相关问题研究的基础上, 提出了可能的反应机理.     

Kinetic determination of iodide, based on the chlorpromazine-bromate reaction

A kinetic method based on the catalytic effect of iodide on the chlorpromazine-bromate reaction is described. The reaction was followed spectrophotometrically by measuring the increase in the absorbance at 525 nm. Under optimal experimental conditions (10(-4)M chlorpromazine hydrochloride, 1.5(itM) phosphoric acid, 5 x 10(-4)M potassium bromate, 40 degrees ), iodide was determined between 5 and 70 ng/ml by the tangent method. The influence of reaction variables, the precision and accuracy of the method and the effect of foreign ions were studied. The procedure was applied to the determination of iodide in iodinated salts and in rat thyroid.     

流动注射化学发光测定盐酸土霉素

水浴加热后的盐酸土霉素在磷酸介质中,过氧化氢存在下与高碘酸钠反应产生强烈的化学发光。结合流动注射技术建立了一种测定盐酸土霉纱的化学发光新方法。方法的线性范围为１．０＊１０＾－８－６．０＊１０＾－６ｇ／ｍＬ盐酸土霉素。检出限为４．３＊１０＾－９ｇ／ｍＬ,ＲＳＤ为２．５％（Ｃｓ＝２．０＊１０＾－６ｇ／ｍＬ;ｎ＝１１）。