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In this study, the flow injection (FI) technology combined with the unique step wise multiple ions monitoring scanning (step-wise MIM) mode of Qtrap-MS was first established for the identification and discrimination of eight Murraya species. It only takes 5 min for each sample to detect approximate 600 compounds. The characteristic MS chromatograms of eight Murraya plants were analyzed by Analyst and SIMCA-P. The results of PCA showed that sect. Murraya and sect. Bergera were clearly divided into two categories, suggesting that there is difference in the chemical compositions between these two groups. Further detail analysis of the MS data could realize the preliminary structure elucidation of the component types contained in different plants. The main components in M. exotica and M. alata are coumarins, and polymethoxyflavones are rich in M. paniculata, while carbazole alkaloids are the major ones in sect. Bergera plants. The results are consistent with our previous comprehensive analysis of the chemical components of Murraya species. In conclusion, our research confirmed that FI-Qtrap-MS technology can be used for rapid identification and differentiation of similar plant species, providing reference for chemical taxonomy and a new method for the quality evaluation of medicinal materials.
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@#Objective To develop and verify a method for determination of cyanide residues in polysaccharide-protein conjugate vaccines based on flow injection analysis(FIA)with amperometric detector.Methods After removing macromolecular substances in the samples by ultrafiltration,the cyanide residues were determined by a 3700 automatic chemical analyzer with the injection time of 35 s,injection volume of 200 μL,pump speed of 40%,sample cycle time of 140 s,ultraviolet wavelength of 312 nm and an Ampere detector.The developed method was verified for the specificity,matrix effect,linear range,limit of detection(LOD),limit of quantitation(LOQ),accuracy,presicion and stability.The cyanide residues in the polysaccharide derivative bulk(13 batches)and conjugate bulk(21 batches)of Haemophilus influenzae type b conjugate vaccine and group A and C meningococcal conjugate vaccine produced by 5 manufacturers were determined by the developed method.Results Blank samples showed no interference to detection;The recoveries of the matrix effector solution of Haemophilus influenzae type b conjugate vaccine polysaccharide derivative and conjugate bulk,group A and C meningococcal conjugate vaccine polysaccharide derivative and conjugate bulk were 97.4%,102.4%,96.8% and 99.8% respectively,with all CV values less than 15%;In the range of 0.312 5 ～ 80 ng/mL,cyanogroup concentration showed a good linear relationship with peak height with a regression equation of y = 133.13 x + 57.556,R2= 0.999 1;The LOD was 0.2 ng/mL,and the LOQ was 0.6 ng/mL.The average recoveries of the control solution were 108.9%,106.5%,103.5% respectively with RSD value of 6.4% in the groups added with 5,10 and 20 ng/mL of cyanogroup and the CV values of precision verification were all less than 15%;The average concentrations of the control solution injected 20 times continuously were 76,38,18and 5 ng/mL with all CV values less than 15%,when cyanogroup concentration was 80,40,20 and 5 ng/mL,respectively.Cyanide residues were detected in 13 batches of derivative bulk samples,while not in 2 batches of 21 batches of polysaccharide conjugate bulk samples,and were detected in the others.Conclusion The developed method had good accuracy,precision and stability,which might be applied to the quantitative determination of cyanide residues in polysaccharideprotein conjugate vaccines.
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Objective@#To establish a continuous flow injection analysis with potassium permanganate for determination of oxygen consumption in water.@*Methods@#The water samples and acid potassium permanganate working solutions were mixed using the continuous flow bubble spacing, and subjected to online heating reaction at 97 ℃. The peak height of the electrical signal of potassium permanganate was measured at the maximum absorption wavelength of 520 nm, and the standard substance, sulfuric acid concentration and potassium permanganate concentration were optimized according to the peak height of the electrical signal. The standard curve was plotted to measure the limit of detection, the limit of quantification, and spiked recovery rate of the method. The CODMn concentration was determined in 40 drinking water samples using acid potassium permanganate titration and continuous flow injection analysis using potassium permanganate, and the determination results of the two methods were compared with paired t-test.@*Results@#Glucose was selected as the standard substance, and the mixture of 17.5% sulfuric acid and 3.2 mmol/L potassium permanganate was selected as the working solution. CODMn had a good linear relationship at concentrations of 0 to 6.00 mg/L, with a correlation coefficient of 0.999 and higher, a detection limit of 0.013 mg/L and a quantitation limit of 0.043 mg/L, respectively. The spiked recovery rates were 90.00% to 105.00% in 40 drinking water samples, with relative standard deviations of 0.12% to 1.36%. The determination results of two permanganate index standard substances were all within the range of standard values. The relative errors of CODMn concentration were 1.55% to 9.26% between the continuous flow injection analysis using potassium permanganate and acid potassium permanganate titration, and there was no significant difference (t=2.023, P=0.185). @*Conclusion@#The established continuous flow injection analysis with potassium permanganate is feasible for batch determination of oxygen consumption in water.
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Objective To establish a catalytic spectrophotometric method for determination of iodine in water without the use of highly toxic arsenic reagents with good precision and accuracy.Methods A new flow injection catalytic spectrophotometry method for determination of iodine in water was established by combining flow injection analysis (FIA) with a new catalytic spectrophotometry for determination of iodine with no need of arsenic reagent.The standard curve linearity,sample detection limit,precision and accuracy of different iodine content ranges (0-250,0-1 200 μg/L) were tested.The test result was compared with that of the arsenic-based catalytic spectrophotometry recommended by the iodine deficiency disorders monitoring program in China (recommended monitoring method).Results A calibration relation of C =aA2 + bA + d (C:iodine concentration,A:measuring absorbance peak area from FIA) of the new method existed in the range of 0-250 and 0-1 200 μg/L.The linear correlative coefficient were both 0.999 9.The detection limit for iodine in water was 0.3 μg/L.The FIA peak shape of the sample tube with the lowest content is determined,and the sensitive iodine signal is detected.The water samples with different iodine content ranges were determined in parallel for 6 times,and the coefficient of variation (CV) was 0.2％-2.7％;the recoveries ranged from 95.0％ to 105.0％,and the total average recovery was 100.3％.The measured values of water iodine standard material GBW 09113e [(8.2 ± 1.2) μg/L] and GBW 09114d [(62.0 ± 6.0) μg/L] in the standard curve of different iodine contents were all within the uncertainty range of the given value.There was no significant difference between the results of recommended monitoring method and the new method (t =0.781,P ＞ 0.05).Conclusions The new method for measuring water iodine has a wide standard curve range,high sensitivity,and good precision and accuracy.The instrument is easy to operate,and no need for toxic arsenic reagent.The method is a reliable method for water iodine detection.
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Objective To establish a catalytic spectrophotometric method for determination of iodine in urine without the use of highly toxic arsenic reagents and with good precision and accuracy. Methods Combined flow injection analysis (FIA) with new catalytic spectrophotometry, a new method for determination of iodine with no need of arsenic reagents was developed by the author. An ammonium persulfate digestion-flow injection catalytic spectrophotometry for determination of iodine in urine was established. Standard serial solutions and urine samples were all digested by ammonium persulfate before testing. The standard curve linearity in the range of 0-1200μg/L, detection limit,precision and accuracy in determining urinary iodine were tested. Results A good calibration relation of C=aA2+bA+d (C:iodine concentration,A:measuring absorbance peak area from FIA) of the newly developed method existed in the range of 0 - 1200 μg/L. The linear correlative coefficient was 0.9998. The FIA analysis speed was 60 samples per hour. The detection limit for urinary iodine was 7.1μg/L. Precision:The intra-assay coefficients of variation (CV) were 0.3％ - 3.0％ (n = 6) when measuring 9 urine samples with iodine concentration of 61.8-806.8μg/L;the intra-assay CV were 0.2％-1.7％(n=6) when measuring 5 urinary iodine national standard materials with iodine concentration of 76.9 - 883.0 μg/L; the inter-assay CV were 1.0％ - 1.2％ when measuring 6 batches of 3 urinary iodine national standard materials with iodine concentration of 76.9 - 232.0 μg/L. Accuracy:The average recovery rate was 98.3％ with a range of 91.2％ - 104.6％ when measuring 20 urine samples with iodine concentration ranged from 18.9 to 807.1 μg/L. The test results of 5 urinary iodine national standard materials were all within the given value range and the relative deviations ranges were-2.9％-0.7％. No significant difference was found between the results of the 48 urine samples determined by the current standard method (WS/T 107.1-2016) and the new method (t=0.029, P>0.05). Conclusions The new method has a wide standard curve range, high sensitivity, good precision and accuracy, and is simple and easy to operate, with automatic sampling, rapid analysis, and no need for toxic arsenic reagent which is difficult to obtain and can pollute the environment. The method is suitable for widely application and can be used as a reliable technical method for urinary iodine detection.
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A novel flow-injection chemiluminescence (FI-CL) method free of CL reagent was developed for the determination of captopril based on its enhancing effect on the CL derived from diperiodatoargentate(III)-sulfuric acid system. Compared with the conventional CL system, the CL system based on trivalent silver was characterized of good selectivity for the absence of CL reagent. The CL mechanism was discussed through CL spectra and UV–vis absorption spectra. The conditions of the FI-CL system were investigated and optimized. Under the optimal conditions, the relative CL intensity was linear with the captopril concentration in the range of 0.3–15.0 μg/mL. The detection limit for captopril was 0.05 μg/mL, and the relative standard deviation (n=11) was 2.0% for 5.0 μg/mL captopril. The proposed method was applied to the analysis of captopril in tablet and human urine with the recoveries of 83.1%–112.5%, and the relative standard deviations of 0.5%–4.4%. The results obtained by the proposed method agreed well with those obtained from HPLC method. The proposed method is fast, convenient, and cost-effective for the determination of captopril in medicine and biological samples.
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The lymphatic system plays an important role in human health and disease. In addition to a role in the immune response, the lymphatics can also serve as a pathway for cancer metastasis.Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers.In the case where the primary focus has been controlled, cervical lymph node metastasis is one of the most important factors affecting the prognosis of head and neck cancer.Thus, understanding the anatomy of the lymphatic system is of paramount importance in predicting cancer metastasis and to perform proper lymph node dissection in cancer patients.The objective of this review is to summarize current imaging approaches that facilitate both basic science and clinical investigations of lymphatic vasculature.Mutation analysis of the laryngeal lymphatic system may provide a theoretical basis for the diagnosis and treatment of HNSCC.
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Spectrophotometric seawater pH measurement system is an urgent need of device due to its quick speed and high precision. Based on spectrophotometric method and flow injection analysis technique, an automated system for pH measurement of seawater was developed by integrating pump and valve flow path, LED light source, flow cell and spectrophotometer. This measurement system effectively avoided bubbles. The indicator of concentration gradient in the seawater sample was used to correct for the pH perturbation caused by the indicator, thus the operation of system was simple and convenient. with this system, only 1. 5 min was needed for a sample measurement with a precision of 0. 0013 pH units and an offset of 0. 0059 pH units. This system could be used for the rapid determination of pH of seawater collected by laboratory or research ship with high precision pH values.
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Objective To establish a method for automatic determination of iodine content in drinking water by flow injection analysis (FIA) without arsenic. Methods In the dilute nitric acid solution, iodide ion in appropriate amount of nitrous acid solution could catalyze the orange red iron thiocyanate complex fade, and the use of this method combined with flow injection analysis technology formulated a flow injection method, and experimental conditions of the method were optimized. The linear relationship and linear range of the standard curve, the detection limit, the precision and the accuracy of the sample determination were implemented under the optimized conditions. Results The optimum concentration of potassium thiocyanate solution (0.15 mol/L) and sodium nitrite was 27.30 ml and 8.00 g/L, respectively, by series of experimental studies. Under the condition, the linear range of the standard curve was 0-500μg/L, the standard curve linear relationship coefficient≥0.9990;method detection limit was 5.94μg/L; in precision experiment of low, medium and high concentrations of iodine, the coefficients of variation were 1.19%, 1.92%and 2.06%;in accuracy test, recovery rates were 100.49%-107.84%, and the total recovery rate was 103.15%. Conclusions The flow injection analysis method can be used to replace arsenic cerium catalyzed spectrophotometric detection of iodide in water; when the method is used in detection of the sample water iodide content of 0 - 500 μg/L, it has good precision and accuracy, automatic injection, automatic filling reagents and automatic detection system to reduce the burden on the staff, with arsenic-free reagents and reduced environmental pollution and the health hazards of the inspectors, which is suitable for iodine screening in high iodine areas.
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Introduction Chronic otomastoiditis causes pain, otorrhea, and hearing loss resulting from the growth of tissue within the normally hollow mastoid cavity. Objectives In this report, we used a lipidomics approach to profile major mastoid bone and tissue lipids from patients with and without otomastoiditis. Methods The bone dust created during mastoidectomy, as well as the mastoid tissue, was analyzed from seven patients. Bone dust was also collected and analyzed in an additional four otologic cases (parotidectomy requiring mastoidectomy). Samples were subjected to a modified Bligh/Dyer lipid extraction, then high-performance thin-layer chromatography (HPTLC), combined gas chromatography/electron impact-mass spectrometry (GC/EI-MS), and flow-injection/electrospray ionization-tandem mass spectrometry (FI/ESI-MSMS). Data were analyzed for identification and profiling of major lipid components. Results HPTLC revealed the presence of various lipid classes, including phosphatidylcholines, cholesterol, and triacylglycerols. GC/EI-MS analysis revealed the presence of cholesterol and several fatty acids. FI/ESI-MSMS analysis revealed a host of phosphatidylcholines, phosphatidylethanolamines, and cholesteryl esters. Conclusion We used a lipidomics approach to develop an efficient (both in time and tissue amount) methodology for analysis of these tissues, identify the most abundant and common lipid species, and create a base of knowledge from which more focused endeavors in biomarker discovery can emerge. In an effort toward improved patient categorization and individualized intervention, the ultimate goal of this work is to correlate these lipid molecules to disease state and progression. This is the first reported study of its kind on these tissues. .
Subject(s)
Humans , Mucocutaneous Lymph Node Syndrome/diagnosis , Mucocutaneous Lymph Node Syndrome/drug therapy , Coronary Aneurysm/etiology , Glucocorticoids/therapeutic use , Immunoglobulins, Intravenous/therapeutic use , Mucocutaneous Lymph Node Syndrome/etiology , Mucocutaneous Lymph Node Syndrome/physiopathology , Risk Factors , Tumor Necrosis Factor-alpha/antagonists & inhibitorsABSTRACT
Objective: To study three different extraction processes of the content of total flavonoids in Chrysanthemum indicum and their anti-oxidant activities. Methods: The reflux, ultrasonic, and tissue-breaking methods were used for extracting the total flavonoids from C. indicum, which were determined by UV spectrophotometry, and the anti-oxidant activity was determined by flow injection chemiluminescence. Results: The contents of total flavonoids obtained using various methods, such as reflux, ultrasonic, and tissue- breaking, were 12.60, 11.02, and 10.95 mg/g, and their IC50 were 2.67, 3.43, and 5.13 μg/mL, respectively. Conclusion: The research indicates that the reflux extraction method is applied to isolatting the total flavonoids from C. indicum, with the advantage of high extraction efficiency, and the total flavoniods show the strong anti-oxidant activity.
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Objective To establish a new method for the rapid and sensitive determination of biapenem. Methods A simple, rapid and sensitive flow injection chemiluminescence(CL) method for the determination of biapenem was developed based on the fact that biapenem could enhance the CL of the luminol (LMN)-potassium ferricyanide reaction system under an alkaline condition. Results Under the optimal experimental conditions, we obtained a linear relationship between the CL intensity and the concentration of biapenem in the range of 0.02%0.6 mg/L with a detection limit of 7.3 x10-3 mg/L. The relative standard deviation was 1.76% for the eleven-time determination of 0.2 mg/L biapenem. Conclusion The method shows high sensitivity, low detection limit and good repeatability. It has been successfully applied to the determination of biapenem for injection and the results are satisfactory.
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Objective To establish a new method for the rapid and sensitive determination of biapenem. Methods A simple, rapid and sensitive flow injection chemiluminescence(CL) method for the determination of biapenem was developed based on the fact that biapenem could enhance the CL of the luminol (LMN)-potassium ferricyanide reaction system under an alkaline condition. Results Under the optimal experimental conditions, we obtained a linear relationship between the CL intensity and the concentration of biapenem in the range of 0.02~0.6 mg/L with a detection limit of 7.3×10-3 mg/L. The relative standard deviation was 1.76% for the eleven-time determination of 0.2 mg/L biapenem. Conclusion The method shows high sensitivity, low detection limit and good repeatability. It has been successfully applied to the determination of biapenem for injection and the results are satisfactory.
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A flow-injection chemiluminescence ( FI-CL ) reaction system with diperiodatoargentateⅢ was developed for the determination of hydrocortisone in human serum. The weak chemiluminescence signal from the reaction between DPA and sulfuric acid system can be greatly enhanced in the presence of hydrocortisone. The optimal conditions of the CL system were 1. 0 mol/L H2SO4, 2. 5×10-4 mol/L diperiodatoargentateⅢ, and flow rate of 4. 20 mL/min. Under the optimal conditions, the CL intensity was linearly to the concentration of hydrocortisone from 3 . 0 × 10-10 g/mL to 1 . 0 × 10-7 g/mL and the detection limit was 2 . 2 × 10-10 g/mL ( 3σ) . The relative standard deviation ( RSD ) was 0 . 6% ( n =11 ) for 5 . 0 × 10-8 g/mL hydrocortisone solution. The proposed method was successfully applied to the direct determination of hydrocortisone in serum samples with the recoveries of 93 . 0%-110 . 0%, and the relative standard deviations were 0 . 3%-3 . 2%. The possible chemiluminescence mechanism was investigated by measuring fluorescence spectra and UV-vis absorption spectra of the system.
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Objective: To study the quality of Eucommiae Cortex from different resources using flow injection mass spectrometric fingerprinting (FIMS) method combined with chemical pattern recognition approaches. Methods: Different Eucommiae Cortex samples were extracted in a simple way and were directly injected into the mass spectrometer for the analyses with no column used. Based on the intensities of the ions at m/z 100-1000, principal components analysis and partial least square discrimination analysis were performed using Simca-P software. Results: Eucommiae Cortex samples from different resources were classified into four clusters in scores plot, and the biomarkers which played the most important roles in classification were screened out. Conclusion: As a novel and characteristic fingerprinting method, FIMS can be widely and efficiently used in true or false identification, identification of origins, and rapid discrimination of herbs from different regions.
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A novel chemiluminescence (CL) reaction was based on the oxidizing reaction of luminol by the trivalent copper-periodate complex (K5[Cu(HIO6)2], DPC) in alkaline medium. The CL intensity could be enhanced in the presence of amikacin sulfate (AKS). A new CL method was developed for the determination of AKS by coupling with flow injection (FI) technology. Because of the distinctive oxidative effect of DPC, the luminol-based CL reaction could occur at a low concentration of 10à7 M. The relative CL intensity was proportional to the concentration of AKS in the range of 4.0 ? 10à9-4.0 ? 10à6 g/mL with the detection limit of 1.2 ? 10à9 g/mL. The relative standard deviation was 2.1% for 8.0 ? 10à9 g/mL AKS (n?9). The proposed method was successfully applied to the direct determination of AKS at the level of ng/mL in serum samples. The recovery varied from 97.0% to 106.3%. A possible mechanism of the CL reaction was discussed in detail by relating to the CL kinetic characteristics and electrochemical activities of the oxidant DPC.
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El presente estudio tiene por objetivo comparar los niveles séricos de cobre (Cu), cinc (Zn) y el cociente molar Cu/Zn en 129 pacientes con artritis reumatoide (RA), en 94 individuos sanos como grupo control (GC) y 21 pacientes con enfermedades reumáticas no artríticas (NER), como la fibromialgia, espondilitis anquilosante entre otras. Las concentraciones séricas de Cu y Zn fueron analizadas por espectroscopía de absorción atómica en llama acoplada a un sistema de inyección en flujo continuo (EAA/FIA). Los resultados muestran un incremento significativo (p<0,05), del cobre sérico en los pacientes con AR en comparación con los otros grupos (NER y GC), este aumento fue directamente proporcional a la actividad inflamatoria de la enfermedad. El nivel medio de cinc sérico mostró una disminución progresiva. Asimismo, el detrimento sérico del cinc está relacionado con la evolución de la enfermedad o la pérdida de capacidad funcional del paciente con los niveles alterados de cobre observados en pacientes con AR activo y en etapa temprana de la enfermedad (p<0,05). Los cocientes molares de Cu/Zn fueron de 1,88; 1,14 y 1,18 para la AR, GC, y NER, respectivamente, demostrando que su modificación es más notoria que evaluar cada oligoelemento por separado. Estos hallazgos sugieren que existe una redistribución tanto del cobre como del cinc en muchos compartimientos del cuerpo, como respuesta inflamatoria. Por lo que niveles séricos de Cu, Zn y Cu/Zn molar puede ser un criterio valioso para la evaluación clínica y posiblemente, para el estudio y seguimiento de los pacientes con AR.
The aim of this study was to measure the serum levels of copper (Cu) and zinc (Zn) in 129 patients with rheumatoid arthritis (RA), in 94 healthy subjects (HS) and in 21 patients with non-rheumatic diseases (NRD) such as osteoarthritis, fibromyalgia, and ankylosing spondylitis. Serum concentrations of Cu and Zn were measured by flow injection analysis/flame atomic absorption spectroscopy (FIA/FAAS). The Cu/Zn molar ratio in serum also was evaluated in these patients. The result shown that the average concentration of serum copper in patients with RA was significantly increased (p <0.05), on comparing with other patients. This increase was directly proportional to staging or disease progression while zinc concentration was significantly lower in patients with RA, but no differences were found between the stages of the disease. The values of Cu/Zn ratio were 1.88, 1.14 and 1.18, for AR, HS, and NRD patients, respectively. In conclusion, in patients with RA serum copper tend to increase and serum Zn tend to decrease and Cu/Zn molar ratio increases significantly (p<0.05). In conclusion, our results suggest that serum Cu, Zn and Cu/Zn molar ratio could be valuable criteria for clinical evaluation and possibly follow-up study of patients with RA.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Aged , Arthritis, Rheumatoid/complications , Spectrum Analysis/instrumentation , Zinc/analysis , Copper/analysis , Spectrophotometry, Atomic/methods , Chemistry Techniques, Analytical , Public HealthABSTRACT
A simple flow-injection analysis procedure was developed for determining captopril in pharmaceutical formulations employing a novel solid-phase reactor containing silver thiocyanate immobilized in a castor oil derivative polyurethane resin. The method was based on silver mercaptide formation between the captopril and Ag(I) in the solid-phase reactor. During such a reaction, the SCN- anion was released and reacted with Fe3+, which generated the FeSCN2+ complex that was continuously monitored at 480 nm. The analytical curve was linear in the captopril concentration range from 3.0 × 10-4 mol L-1 to 1.1 × 10-3 mol L-1 with a detection limit of 8.0 × 10-5 mol L-1. Recoveries between 97.5% and 103% and a relative standard deviation of 2% for a solution containing 6.0 × 10-4 mol L-1 captopril (n = 12) were obtained. The sample throughput was 40 h-1 and the results obtained for captopril in pharmaceutical formulations using this procedure and those obtained using a pharmacopoeia procedure were in agreement at a 95% confidence level.
Um procedimento simples de análise por injeção em fluxo foi desenvolvido para a determinação de captopril em formulações farmacêuticas empregando um novo reator em fase sólida contendo tiocianato de prata imobilizado em resina poliuretana obtida a partir de óleo de mamona. O método foi baseado na formação de um mercapto composto de prata, no reator em fase sólida, obtido entre o captopril e Ag (I) imobilizada. Durante a reação, íons SCN- eram liberados e reagiam com Fe3+, gerando o complexo FeSCN2+, que foi continuamente monitorado em 480 nm. A curva analítica foi linear no intervalo de concentração de captopril entre 3,0 × 10-4 a 1,1 × 10-3 mol L-1 com um limite de detecção de 8,0 × 10-5 mol L-1. Recuperações entre 97,5-103% e desvio padrão relativo de 2% para uma solução contendo 6,0 × 10-4 mol L-1 de captopril (n = 12) foram obtidos. A frequência de amostragem foi de 40 h-1 e os resultados obtidos para captopril em formulações farmacêuticas utilizando este procedimento e o da Farmacopeia, estão de acordo em um nível de confiança de 95%.
Subject(s)
Captopril/pharmacokinetics , Chemistry, Pharmaceutical/classification , Flow Injection Analysis , Polyurethanes/classificationABSTRACT
El análisis químico día a día se acerca más a la automatización, buscando satisfacer las necesidades actuales de resultados rápidos y confiables. Los sistemas de análisis en flujo (FIA - Flow Injection Analysis) son una de las formas de aproximarse a la automatización. En este artículo se presentan los pasos necesarios para implementar una metodología FIA, para la determinación de Pb(II) en agua, partiendo de la revisión de los procedimientos clásicos y describiendo detalladamente los pasos necesarios para implementar la técnica de análisis en flujo. El trabajo produjo un método de análisis de Pb en agua que usa ditizona disuelta en isopropanol (agente cromogénico), en presencia de bromuro de cetiltrimetil amonio (CTAB), para solubilizar en agua el complejo, cuyas características más sobresalientes fueron: volumen de inyección de muestra de 81,7 µL, velocidad de flujo de 8,0 mL/min, tiempo de toma de espectros 1,4 s e intervalo lineal de 1,0 a 40 mg L-1.
Chemical analysis has evolved towards automation to satisfy the current requirements: fast analysis and certainty in the results. Flow injection analysis (FIA) is a way to reach automation. This work presents the necessary steps to obtain an optimized FIA methodology for the determination of Pb(II) in water by classic methods. The result was a FIA method to determinate Pb with dithizone (chromogenic agent) dissolved in iso-propyl alcohol, using cethyltrimethylammonium bromide (CTAB) to solubilize the complex. The main characteristics of the method were: injection sample volume 81.7 µL, flow 8.0 mL/min, spectra acquisition time 1.4 s and linear range 1 to 40 mg L-1.
Cada dia, a análise química é mais cerca da automatização com o fim de satisfazer as necessidades atuais de resultados rápidos e confiáveis. Os sistemas de análise em fluxo (FIA - Flow Inyection Analysis) são uma das formas de aproximação à automatização. Este artigo apresenta os passos necessários para implementar uma metodologia FIA para a determinação de Pb(II) em água, partindo da revisão dos procedimentos clássicos e descrevendo detalhadamente os passos necessários para implementar a técnica de análise em fluxo. Os resultado são um método de análise de Pb em água que usa ditizona dissolvida em isopropanol (agente cromogénico) na presença de bromuro de cetiltrimetil amônio (CTAB), usado para solubilizar o complexo em água. As características principais do método foram: volume de injeção de amostra de 81,7 µL, velocidade de fluxo de 8,0 mL min-1, tempo de aquisição de espectros de 1,4 s e intervalo linear de 0.9 a 40 mg L-1.
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This paper reports on development of a system consisting of a portable sequential injector coupled with potentiometric unit for sensing of chlorpheniramine (CPA), based on the reaction of CPA with potassium permanganate in acidic media. Various experimental conditions affecting the potential intensity were studied and incorporated into the procedure. Under the optimum conditions, linear relationship between the CPA concentration and peak area was obtained for the concentration range of 0.1-50ppm. The method reflects good recovery with relative standard deviation (RSD)＜3％. The detection limit was 0.05 ppm. The developed method was successfully applied for determination of CPA in pure form and in pharmaceutical dosage forms. The results, obtained using the method, are in accord with the results of the British pharmacopoeia method. In addition to its accuracy and precision, the method has the advantages of being simple, inexpensive and rapid.