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Simple and sensitive determination of sparfloxacin in pharmaceuticals and biological samples by immunoassay 被引量:2
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作者 Hua-Jin Zenga,Ran Yangb,Bing Liub,Li-Fang Leib,Jian-Jun Lib,Ling-Bo Qub,c,n aSchool of Pharmaceutical Sciences,Zhengzhou University,Zhengzhou 450001,China bDepartment of Chemistry,Zhengzhou University,Zhengzhou 450001,China cSchool of Chemistry & Chemical Engineering,Henan University of Technology,Zhengzhou 450001,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2012年第3期214-219,共6页
Plasma quinolone concentrations are not routinely measured in clinical practice.However,in order to optimize quinolone treatment,monitoring of plasma concentrations could sometimes be useful particularly in critically... Plasma quinolone concentrations are not routinely measured in clinical practice.However,in order to optimize quinolone treatment,monitoring of plasma concentrations could sometimes be useful particularly in critically ill patients.In this study,anti-sparfloxacin antibody was obtained by immunizing rabbits with sparfloxacin conjugated with bovine serum albumin using isobutyl chloroformate method.After the assay procedure was optimized,the standard curve of sparfloxacin was established.The practical measuring range of the competitive ELISA extended from 5 ng/mL to 2 mg/mL.The recovery rates and coefficients of variation for rat plasma,urine and tissues were 87.7-106.2% and 4.8-15.3%,respectively.To demonstrate the potential of the ELISA,a preliminary pharmacokinetics and tissue distribution study of sparfloxacin in rats and quantitative analysis of sparfloxacin in several pharmaceuticals were performed and compared with high-performance liquid chromatography(HPLC).The experimental data indicated that the proposed method would be a valuable tool in therapeutic drug monitoring(TDM) for sparfloxacin. 展开更多
关键词 SPARFLOXACIN Enzyme-linked immunosorbent assay(ELISA) biological samples PHARMACOKINETICS Tissue distribution
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Determination of Trace Rare Earth Elements in Biological Samples by ICP-AES with Tungsten-spiral Electrothermal Vaporization Sampling 被引量:1
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作者 梅二文 刘慧 +1 位作者 廖振环 江祖成 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第1期52-57,共6页
A method for determination of trace rare earth elements in biological sample by ICP-AES with tungsten-spiral electrothermal vaporization(TETV-ICP-AES)sampling has been developed in this work. Several influencing facto... A method for determination of trace rare earth elements in biological sample by ICP-AES with tungsten-spiral electrothermal vaporization(TETV-ICP-AES)sampling has been developed in this work. Several influencing factors including desolvation and vaporization parameters,carrier gas flow rate and ma- trix effect were investigated in detail.Under optimal experimental conditions,the detection limits for La,Nd, Gd,Dy,Ho,Yb,Lu and Y were obtained in the range of 10^(-9)~10^(-11) g,and they are comparable to and,in most instances,better than those for the GFAAS and conventional pneumatic nebulisation-ICP-AES.The precision(RSD)obtained for this method is less than 6%. 展开更多
关键词 Tungsten-spiral electrothermal vaporization sampling ICP-AES REE biological sample
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Fabrication of edge-curled petals-like covalent organic frameworks and their properties for extracting indole alkaloids from complex biological samples 被引量:1
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作者 Fanrong Sun Ligai Bai +4 位作者 Mingxue Li Changqing Yu Haiyan Liu Xiaoqiang Qiao Hongyuan Yan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第1期96-103,共8页
In this study,a functionalized covalent-organic framework(COF)was first synthesized using porphyrin as the fabrication unit and showed an edge-curled,petal-like and well-ordered structure.The synthesized COF was then ... In this study,a functionalized covalent-organic framework(COF)was first synthesized using porphyrin as the fabrication unit and showed an edge-curled,petal-like and well-ordered structure.The synthesized COF was then introduced to prepare porous organic polymer monolithic materials(POPMs).Two composite POPM/COF monolithic materials with rod shapes,referred to as sorbent A and sorbent B,were prepared in stainless steel tubes using different monomers.Sorbents A and B exhibited relatively uniform porous structures and enhanced specific surface areas of 153.14 m;/g and 80.01 m;/g,respectively.The prepared composite monoliths were used as in-tube solid-phase extraction(SPE)sorbents combined with HPLC for the on-line extraction and quantitative analytical systems.Indole alkaloids(from Catharanthus roseus G.Don and Uncaria rhynchophylla(Miq.)Miq.Ex Havil.)contained in mouse plasma were extracted and quantitatively analyzed using the online system.The two composite multifunctional monoliths showed excellent clean-up ability for complex biological matrices,as well as superior selectivity for target indole alkaloids.Method validation showed that the RSD values of the repeatability(n=6)were≤3.46%,and the accuracy expressed by the spiked recoveries was in the ranges of 99.38%-100.91%and 96.39%-103.50%for vinca alkaloids and Uncaria alkaloids,respectively.Furthermore,sorbents A and B exhibited strong reusability,with RSD values≤5.32%,which were based on the peak area of the corresponding alkaloids with more than 100 injections.These results indicate that the composite POPM/COF rod-shaped monoliths are promising media as SPE sorbents for extracting trace compounds in complex biological samples. 展开更多
关键词 Covalent organic frameworks Monolithic material Solid-phase extraction ALKALOIDS biological samples
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Organic and Inorganic Mercury in Biological Samples of Flouresecent Lamp Industries Workers and Health Risks
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作者 Nayab GUL Sardar KHAN +3 位作者 Abbas KHAN Javed NAWAB Adnan SARWAR Nida GUL 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第2期89-102,共14页
Objective The present study aims to investigate the concentrations of Hg and its aspects methyl mercury(Me-Hg)and inorganic mercury(I-Hg)in the biological samples(BSs)of fluorescent lamp industries workers(FLIWs).Meth... Objective The present study aims to investigate the concentrations of Hg and its aspects methyl mercury(Me-Hg)and inorganic mercury(I-Hg)in the biological samples(BSs)of fluorescent lamp industries workers(FLIWs).Methodology Different BSs including red blood cells(RBCs),plasma,urine,hair and nails were collected from the workers exposed to Hg and unexposed persons were selected as control group to measure both the T-Hg concentration as well as its species in different biological samples through quantitative analysis.Health data was collected through questionnaire survey.Results The mean concentrations of T-Hg(31.9μg/L),Me-Hg(27.7μg/L),and I-Hg(5.36μg/L)in RBCs were found significantly(P<0.001)higher among the workers(n=40)as compared to the control group(n=40).Similarly the mean Hg concentrations in plasma,urine,hair and nails were also significantly higher among the workers than the control group.The statistical relation between Hg concentration and demographic characteristics observed that workers experience and fish consumption has increased the Hg concentration while age,weight and smoking found no significant effect on Hg concentration in the BSs.Conclusion The study observed that the workers were highly exposed to high concentration of Hg and they are at a high health risk. 展开更多
关键词 MERCURY Health risk FLUORESCENT LAMP INDUSTRIES Regression DEMOGRAPHIC characteristics biological samples
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Study of Direct Determination of Trace Lanthanum in Biological Samples by ICP-AES Combined with Fluorination Electrothermal Vaporization Technique
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作者 秦永超 江祖成 +2 位作者 蔡祥歆 张淑娴 曾云鹗 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第1期54-58,共5页
A new method for direct determination of lanthanum in solid biological materials by fluorination electrothermal vaporization ICP-AES technique with polytetrafluoroethylene(PTFE) disperser as a fluorination agent has b... A new method for direct determination of lanthanum in solid biological materials by fluorination electrothermal vaporization ICP-AES technique with polytetrafluoroethylene(PTFE) disperser as a fluorination agent has been described. The effect of particle size on the signal intensity of La has been investigated. The vaporization behaviour of lanthanum and the main factors affecting fluorinating vaporization have been observed.Under optimum experimental conditions,the detection limit of La to this method is 2.0 ng/ml,and the RSD is 4.5%.The proposed method has been applied to determining directly trace lanthanum in solid biological standard reference materials without any chemical pretreatment,and the determined values are in good agreement with the certified ones. 展开更多
关键词 Fluorination vaporization Particle size effect biological sample LANTHANUM Inductively coupled plasma atomic emission spectroscopy
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Copper and Mercury in Food, Biological and Pharmaceutical Samples: Spectrophotometric Estimation as Cu(DDTC)<sub>2</sub>
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作者 Mohammad Nasir Uddin Nur Mostaq Shah +1 位作者 Mohammad Amzad Hossain Md. Muzahidul Islam 《American Journal of Analytical Chemistry》 2014年第13期838-850,共13页
An alternative spectrophotometric method was optimized and validated for the estimation of mercury using diethyldithiocarbamate (DDTC), a common reagent, widely used for the preconcentration and isolation of metal ion... An alternative spectrophotometric method was optimized and validated for the estimation of mercury using diethyldithiocarbamate (DDTC), a common reagent, widely used for the preconcentration and isolation of metal ions in complex matrices followed by their estimation by varied techniques. Diethyldithiocarbamate forms yellow Cu(DDTC)2 with copper and white Hg(DDTC)2 with mercury (having d10 system) which are extracted in CCl4. The UV-visible spectrum of Cu(DDTC)2 is very stable at pH 5.0 and has a maximum absorption (λmax) at 435 nm. Hg(DDTC)2 is more stable than Cu(DDTC)2. Estimation of mercury is based on a quantitative displacement of Cu(II) of Cu(DDTC)2 with the addition of mercury followed by the measurement of reduced absorbance. Primarily, method was optimized and validated for the estimation of copper. Therefore, simultaneous determination of Cu(II) and Hg(II) in mixture is proposed fractionating the extract. The molar specific coefficient (ε) for the mercury was 1.4 × 104 mol﹣1·L·cm﹣1 and for copper was 3.16 × 105 mol﹣1·L·cm﹣1 at 435 nm. The detection limits of Cu2+ and Hg2+ were 0.023 μg·mL﹣1 and 0.029 μg·mL﹣1, respectively. The calibration curve shows good linearity of 0.02 - 12.0 and 0.02 - 15.0 μg·mL﹣1 for the Cu2+ and Hg2+ determination, respectively. Proposed technique was applied to food, biological and pharmaceutical samples for the determination of Cu(II) and Hg(II). 展开更多
关键词 COPPER MERCURY DIETHYLDITHIOCARBAMATE Spectrophotometric Method FOOD biological Pharmaceutical samples
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Interaction between Cadmium and Zinc Levels in the Biological Samples of Type 1 Diabetic Mellitus Children, Reside in Different Areas of Sindh, Pakistan
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作者 Anjum Lashari Hassan Imran Afridi +4 位作者 Tasneem Gul Kazi Farah Naz Talpur Jameel Ahmed Baig Ghulam Qadir Chanihoon Ghulam Mustafa Channa 《American Journal of Analytical Chemistry》 2021年第6期241-259,共19页
Type 1 Diabetes mellitus (T1DM) is one of the familiar childhood immune-mediated onsets and can lead to early mortalities and morbidities. It can arise at any stage, but the peak of occurrence is reported less than 18... Type 1 Diabetes mellitus (T1DM) is one of the familiar childhood immune-mediated onsets and can lead to early mortalities and morbidities. It can arise at any stage, but the peak of occurrence is reported less than 18 years of age. T1DM cases in Pakistan were less than 2% of the total diabetic population. The current work designed to assess the concentration of cadmium (Cd) and zinc (Zn) in blood, scalp hair and serum samples of T1DM children, age ranged 1 - 14 years of both genders. For comparison purpose, the age-matched referent subjects of both genders were tested. The microwave-assisted acid digestion procedure was used to determine the elemental analysis in the biological samples of T1DM children and referent subjects. The resulted data of certified reference material of blood, scalp hair, and serum validated the certainty of the designed method. The analysis of Zn was performed by flame atomic absorption spectrometry, while the Cd contents were determined by electrothermal atomic absorption spectrometry. T1DM affected children of both genders have lower Zn level in the blood, scalp hair, and serum samples. Whereas, the levels of Cd were found to be higher in the biological samples of T1DM affected children as compared to referent subjects. The finding of the current study is a significant hypothesis for medical experts, to diagnose the deficiency of essential (Zn) and toxicity of heavy/toxic element (Cd) in the biological specimen of T1DM affected children. 展开更多
关键词 ZINC CADMIUM biological samples Type 1 Diabetic Mellitus CHILDREN
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A Highly Sensitive and Selective Spectrofluorimetric Method for the Determination of Arsenic at Pico-Trace Levels in Some Groundwater, Real, Environmental, Biological, Food and Soil Samples Using 2-(<i>α</i>-Pyridyl)-Thioquinaldinamide
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作者 M. Jamaluddin Ahmed Ayesha Afrin Mamunur Rashid 《American Journal of Analytical Chemistry》 2019年第8期316-347,共32页
A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been develope... A very simple, ultra-sensitive, highly selective and non-extractive new spectrofluorimetric method for the determination of arsenic at pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of Arsenic (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.025 - 0.1 M H2SO4) solution with Arsenic (V) in absolute ethanol to produce highly fluorescent oxidized product (λex = 303 nm;λem = 365 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.025 - 0.1 M H2SO4) for the period between 2 min and 24 h. Linear calibration graphs were obtained for 0.001 - 800-μgL-1 of As, having a detection limit of 0.1-ngL-1;the quantification limit of the reaction system was found to be 1-ngL-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexion agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN, etc.) do not interfere in the determination. The developed method was successfully used in the determination of arsenic in several Certified Reference Materials (alloys, steels, ores, human urine, hair, nails, bovine liver and sediments) as well as in some biological fluids (human blood, urine, hair, nail and milk), soil samples, food samples (vegetables, fruits, rice, corn and wheat), solutions containing both arsenic (III) and arsenic (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and soil samples were comparable with both ICP-OES & AHG-AAS and were found to be in excellent agreement. 展开更多
关键词 Spectrofluorimetry ARSENIC Determination GROUNDWATER 2-(α-Pyridyl)-thioquinaldinamide ENVIRONMENTAL biological Soil FOOD samples
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Calcium and Lead Levels in the Biological Samples and Their Effect on the Biochemical Parameters of Indoor and Outdoor Workers of Five Zonal Areas of Coal Mining Field
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作者 Hassan Imran Afridi Qutubuddin Solangi +4 位作者 Tasneem Gul Kazi Farah Naz Talpur Jameel Ahmed Baig Ghulam Qadir Chanihoon Ghulam Mustafa Channa 《American Journal of Analytical Chemistry》 2021年第6期260-276,共17页
Workers of the Lakhra coal mining Sindh Pakistan were affected by a multi-factorial exposure of heavy metals. The prevalence of lead (Pb) exposures in work-related symptoms among workers of indoor and outdoor mining o... Workers of the Lakhra coal mining Sindh Pakistan were affected by a multi-factorial exposure of heavy metals. The prevalence of lead (Pb) exposures in work-related symptoms among workers of indoor and outdoor mining of Lakhra coal mining was evaluated in detail. The biological samples (scalp hair and blood) of 270 workers of Lakhra coal mining {official and control subjects} (indoor and outdoor) 18 to 55 years age group and 70 referent subjects of same age-groups were examined. The biological samples (blood and scalp hair) of workers of Lakhra coal mining and referent subjects were analyzed for calcium (Ca) and lead (Pb). Flame atomic absorption spectrometry was applied for the determination of the Ca in digested samples of studied subjects by the microwave oven whereas, the Pb contents were measured by electrothermal atomic absorption spectrometry. The validity of the methodology was checked by using the certified human hair material (BCR 397) and lyophilized human blood (Clincheck). The results indicated the higher contents of Pb in biological samples of indoor and outdoor mining workers than referents. However, the levels of Ca were found to be lower in indoor and outdoor mining workers than those of referents. It can be concluded that immediate action should be taken by recommended authorities to improve the ventilation and hygiene practices inside the industries, mines, and other workplaces. 展开更多
关键词 Essential Elements Toxic Elements biological samples Lakhra Coal Mining Atomic Absorption Spectrophotometry
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Elemental Concentrations in Biological Samples of Coronavirus Disease (COVID-19) and Other Pulmonary Disease Patients
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作者 Hassan Imran Afridi Tasneem Gul Kazi +4 位作者 Farah Naz Talpur Jameel Ahmed Baig Ghulam Qadir Chanihoon Ayaz Lashari Ghulam Mustafa Channa 《American Journal of Analytical Chemistry》 2021年第5期162-187,共26页
<strong>Background:</strong> Recently, Coronavirus Disease 2019 (COVID-19) has been affected by the extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has developed important global health a... <strong>Background:</strong> Recently, Coronavirus Disease 2019 (COVID-19) has been affected by the extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has developed important global health anxiety. At this time, the treatment options for this disease are only moderately successful. Smoking has been related to COVID-19 and its mortality, and it has the potential to affect bacteriological and viral conversion, clinical effects, and treatment outcomes. <strong>Methods:</strong> The aim of this study was to determine the relationship between critical essential trace {zinc (Zn), iron (Fe), and copper (Cu)} and toxic {cadmium (Cd) and nickel (Ni)} elements in human biological samples such as scalp hair, serum, saliva, blood, nasal fluid, and sputum of smoking and nonsmoking male COVID-19 patients (n = 139, age range 25 - 38 years) from Hyderabad, Pakistan. For comparative purposes, the biological specimens of referent persons (n = 83), pulmonary Tuberculosis (T.B) patients (n = 67), Pneumonia (n = 56) of the same age groups were also be analyzed. Microwave oven mediated digestion method was employed, and digestion of samples was carried out with the help of 2:1 mixture solution of HNO<sub>3</sub> (65%) and H<sub>2</sub>O<sub>2</sub> (30%). Atomic absorption spectrometry was employed for the determination of elemental concentrations from the microwave oven employed digested samples. <strong>Results:</strong> The found average of essential elements (Zn, Fe, and Cu) in biological specimens of smoker and nonsmoker male COVID-19, T.B, and Pneumonia patients was found to lower, whilst cadmium and nickel were found to be higher when compared with samples from referents (p < 0.001). <strong>Conclusions:</strong> Improved elemental (Cu, Fe, Zn) concentrations may also decrease the risk of bacterial co-infection by enhancing the mucociliary clearance and respiratory epithelial barrier function, in addition to providing direct antibacterial effects against <i>S. pneumoniae</i>. Our findings also suggest that higher Cd and Ni concentrations are linked to cigarette smoking, which could lead to COVID-19 and other lung-infected diseased recurrences. However, further clinical and experimental research is required. 展开更多
关键词 COVID-19 Other Lung Infected Diseases Essential Trace Elements Toxic Elements biological samples Age Ranged 25 - 38 Years
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THE USE OF CHELATING RESIN FOR THE PRE-CONCENTRATION OF TRACE RARE EARTH ELEMENTS IN BIOLOGICAL SAMPLES AND THEIR DETERMINATION
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作者 祝孝丰 张田 扆军 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期128-132,共5页
Macroporous amino-carboxvlic chelating resin of acrylic acid series may concentrate trace rare earth in the presence of 0.1 mol/l α-hydroxy-isobutyric acid at pH 4.5.With 0.10 mol/l HCl as eluant rare earth may be el... Macroporous amino-carboxvlic chelating resin of acrylic acid series may concentrate trace rare earth in the presence of 0.1 mol/l α-hydroxy-isobutyric acid at pH 4.5.With 0.10 mol/l HCl as eluant rare earth may be eluted quantitatively and separated from Ca,Mg,Fe and Cu.This method is used to determine trace amount of rare earth in human hair,stone (in kidney and bladder),peanut,grape,strawberry,cucumber,pig liver and other biological samples. 展开更多
关键词 HCI THE USE OF CHELATING RESIN FOR THE PRE-CONCENTRATION OF TRACE RARE EARTH ELEMENTS IN biological samples AND THEIR DETERMINATION PMBP
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Fluorine ion transmission through thin biological samples
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作者 Xue Jian-Ming Wang Yu-Gang +3 位作者 Lu Xi-Ting Yan Sha Chen Jiang Zhao Wei-Jiang (Institute of Heavy Ion Physics, Peking Univcrsity, Beijing 100871) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第4期218-220,共3页
F2+ beam with 3 MeV is used to irradiate thin biological samples (onion innersurface membrane and kidney beau coat) in the transmission measurement, its current densityis 400-800 nA/cm2. Results show that the onion sa... F2+ beam with 3 MeV is used to irradiate thin biological samples (onion innersurface membrane and kidney beau coat) in the transmission measurement, its current densityis 400-800 nA/cm2. Results show that the onion samples can be broken up quickly under ionirradiating; as to kidney beau samples, about 60% of tile implanted ions penetrate the samples,most of them lose part of their energy, fewer ions are found to be able to transmit throughthe sample without energy loss. SEM experiments are carried out to study sample’s damageinduced by tile ions irradiation. 展开更多
关键词 氟离子 离子移植 生物样品 传输测量
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A Highly Sensitive and Selective Spectrofluorimetric Method for the Determination of Vanadium at Pico-Trace Levels in Some Real, Environmental, Biological, Soil and Food Samples Using 2-(<i>α</i>-Pyridyl)-Thioquinaldinamide
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作者 M. Jamaluddin Ahmed Ayesha Afrin Yasmin Akhtar 《American Journal of Analytical Chemistry》 2019年第11期528-561,共34页
A new spectrofluorimetric reagent 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been synthesized and characterized through novel reaction techniques. A very simple, ultra-sensitive and highly selective non-extractive n... A new spectrofluorimetric reagent 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been synthesized and characterized through novel reaction techniques. A very simple, ultra-sensitive and highly selective non-extractive new spectrofluorimetric method for the determination of vanadium at Pico-trace levels using 2-(α-pyridyl)-thioquinaldinamide (PTQA) has been developed. PTQA has been proposed as a new analytical reagent for the direct non-extractive spectrofluorimetric determination of vanadium (V). This novel fluorimetric reagent, PTQA becomes oxidized in a slightly acidic (0.0035 - 0.0085 M H2SO4) solution within vanadium (V) in 20% ethanol to produce highly fluorescent oxidized product (λex = 319 nm;λem = 371 nm). Constant and maximum fluorescence intensities were observed over a wide range of acidity (0.0035 - 0.0085 M H2SO4) for the period between 5 min and 24 h. Linear calibration graphs were obtained for 0.001 - 600-μg·L-1 of V, having a detection limit of 0.3-ng·L-1;the quantification limit of the reaction system was found to be 3-ng·L-1 and the RSD was 0% - 2%. A large excess of over 60 cations, anions and complexing agents (like, chloride, phosphate, azide, tartrate, oxalate, SCN- etc.) do not interfere in the determination. The developed method was successfully used in the determination of vanadium in several Certified Reference Materials (alloys, steels, serum, bovine liver, drinking water, soil and sediments) as well as in some environmental waters (potable and polluted), biological fluids (human blood, urine, hair and milk), soil samples and food samples (vegetables, rice and wheat) solutions containing both vanadium (IV) and vanadium (V) speciation and complex synthetic mixtures. The results of the proposed method for assessing biological, food and vegetable samples were comparable with inductively coupled plasma optical emission spectroscopy (ICP-OES) and atomic-absorption spectrophotometer (AAS) was found to be in excellent agreement. 展开更多
关键词 Spectrofluorimetry Vanadium-Determination 2-(α-Pyridyl)-Thioquinaldinamide ENVIRONMENTAL biological SOIL Food-samples
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ANALYSIS OF STRYCHNINE ALKALOIDS IN BIOLOGICAL SAMPLES BY THIN-LAYER CHROMATOGRAPHIC DENSITOMETRY AND DISTRIBUTION STUDY OF STRYCHNINE IN INTOXICATED RATS
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作者 傅强 贺浪冲 +1 位作者 常春 苗治平 《Journal of Pharmaceutical Analysis》 CAS 1998年第2期146-149,180,共5页
A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer ... A sensitive and rapid analytical procedure was established to detrmine strychnie alkaloids in diverse biological specimens. Samples were treated with hydrochloric acid to precipitate protein and scanned in thin-layer chromatograpic scanner in zig-zag dual-wavelength reflection mode.Detection sensitivity for strychniue was about 0. 05 μg. Quantification recoveries were between89. 2% and 99. 5% with RSD between 2. 92% and 13. 21 %. The method was applied to investigate thedistribution or strychnine in intoxicated rats. The results showed that there were remarkable difference in organs or tissues with the aigaest concentration 4. 56±1. 41μg/g in liver. Diversification experiment proves the method also could be used to analyze other alkaloids in biological samples if theconditions slightly modified. 展开更多
关键词 STRYCHNINE ALKALOIDS biological samples toxicological analysis thin-layer chromatographic densitometry
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Balloon-based exposed payload designed for astrobiological research in Earth’s near space
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作者 YanQiu Wang JianXun Shen +4 位作者 Chao Wang WeiNing Li GaoHong Wang Wei Lin YuanDa Jiang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期878-889,共12页
Earth’s near space,located in the region between 20 and 100 km above sea level,is characterized by extreme conditions,such as low temperature,low atmospheric pressure,harsh radiation,and extreme dryness.These conditi... Earth’s near space,located in the region between 20 and 100 km above sea level,is characterized by extreme conditions,such as low temperature,low atmospheric pressure,harsh radiation,and extreme dryness.These conditions are analogous to those found on the surface of Mars and in the atmosphere of Venus,making Earth’s near space a unique natural laboratory for astrobiological research.To address essential astrobiological questions,teams from the Chinese Academy of Sciences(CAS)have developed a scientific balloon platform,the CAS Balloon-Borne Astrobiology Platform(CAS-BAP),to study the effects of near space environmental conditions on the biology and survival strategies of representative organisms in this terrestrial analog.Here,we describe the versatile Biological Samples Exposure Payload(BIOSEP)loaded on the CAS-BAP with respect to its structure and function.The primary function of BIOSEP is to expose appropriate biological specimens to the harsh conditions of near space and subsequently return the exposed samples to laboratories for further analysis.Four successful flight missions in near space from 2019 to 2021 have demonstrated the high reliability and efficiency of the payload in communicating between hardware and software units,recording environmental data,exposing sample containers,protecting samples from external contamination,and recovering samples.Understanding the effects of Earth’s near space conditions on biological specimens will provide valuable insights into the survival strategies of organisms in extreme environments and the search for life beyond Earth.The development of BIOSEP and associated biological exposure experiments will enhance our understanding of the potential for life on Mars and the habitability of the atmospheric regions of other planets in the solar system and beyond. 展开更多
关键词 Earth’s near space biological sample exposure payload performance testing Mars analog ASTRObiologY
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Analysis of Fatty Acid in Biological Samples Using Liquid Chromatography–Quadrupole-Orbitrap Mass Spectrometry Under Parallel Reaction Monitoring Mode 被引量:1
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作者 Jingxuan Yang Wenjun Guo +3 位作者 Xiaohang Xu Liang Zhao Yajuan Xu Yang Wang 《Journal of Analysis and Testing》 EI CSCD 2024年第2期210-217,共8页
Fatty acids(FAs)are an important class of functional small molecules and participate in a variety of life biological processes.This experiment proposed a liquid chromatography–quadrupole-Qrbitrap mass spectrometry(LC... Fatty acids(FAs)are an important class of functional small molecules and participate in a variety of life biological processes.This experiment proposed a liquid chromatography–quadrupole-Qrbitrap mass spectrometry(LC–Q-Orbitrap MS)method to perform FA profiling under parallel reaction monitoring(PRM)acquisition mode.The FA was derivatized by 2-dimethylaminoethylamine(DMED)to increase the ionization e fficiency and provide the characterized fragment pattern.The mass spectra obtained from full scan,multiple ion monitoring(MIM),and PRM were compared.The results showed that the protonated ion of FA+DMED–H2O was detected and the neutral loss of 45.06 Da was observed in the tandem mass spectrum.The PRM method provided the highest selectivity and sensitivity for FA detection with the help of accurate mass weight and specific neutral loss-based fragments.The method validation was performed using the FA standards and pooled quality control serum sample,which showed that the established method had good repeatability,stability,and linearity.Finally,the developed method was successfully applied to analyze the rat serum and brain tissue samples for the drug e ffi-cacy evaluation of gross saponin of Tribulus terrestris L.fruit(GSTTF)against middle cerebral artery occlusion(MCAO)-induced ischemic stroke.This method has extensive practicability and great potential in the detection of FA,especially for the analysis of samples with complex matrices. 展开更多
关键词 Fatty acid DERIVATIZATION LC-Q-Orbitrap MS Parallel reaction monitoring biological sample
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Accurate and sensitive determination of hydroxychloroquine sulfate used on COVID-19 patients in human urine,serum and saliva samples by GC-MS
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作者 Süleyman Bodur Sezin Erarpat +1 位作者 Omer Tahir Günkara Sezgin Bakırdere 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第3期278-283,共6页
A rapid,accurate,and sensitive analytical method,ultrasonication-assisted spraying based fine droplet formationeliquid phase microextractionegas chromatographyemass spectrometry(UA-SFDF-LPME-GCMS),was proposed for the... A rapid,accurate,and sensitive analytical method,ultrasonication-assisted spraying based fine droplet formationeliquid phase microextractionegas chromatographyemass spectrometry(UA-SFDF-LPME-GCMS),was proposed for the determination of trace amounts of hydroxychloroquine sulfate in human serum,urine,and saliva samples.To determine the best extraction strategy,several liquid and solid phase extraction methods were investigated for their efficiencies in isolation and preconcentration of hydroxychloroquine sulfate from biological matrices.The UA-SFDF-LPME method was determined to be the best extraction method as it was operationally simple and provided accurate results.Variables such as the extraction solvent,spraying number,sodium hydroxide concentration and volume,sample volume,mixing method,and mixing period were optimized for the proposed method using the onevariable-at-a-time approach.In addition,Tukey’s method based on a post hoc comparison test was employed to evaluate the significant difference between the parameters inspected.After the optimization studies,the limit of detection(LOD)and limit of quantification(LOQ)were determined to be 0.7 and 2.4 mg/kg,respectively.The sensitivity of the GC-MS system based on the LOD was enhanced approximately 440-fold when the UA-SFDF-LPME method was employed.Spiking experiments were also conducted for the human serum,urine,and saliva samples to determine the applicability and accuracy of the proposed method.Recoveries for the human serum,urine,and saliva samples were found to be in the ranges of 93.9%-101.7%,95.2%-105.0%,and 93.1%-102.3%,respectively.These results were satisfactory and indicated that the hydroxychloroquine sulfate level in the above biological samples could be analyzed using the proposed method. 展开更多
关键词 Hydroxychloroquine sulfate GC-MS biological samples Dispersive solid phase extraction Liquid phase microextraction
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生物样品中汞的电感耦合等离子体质谱分析与干扰校正方法
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作者 张灵火 马娜 +4 位作者 陈海杰 张鹏鹏 胡梦颖 徐进力 白金峰 《岩矿测试》 CAS 北大核心 2025年第1期140-148,共9页
电感耦合等离子体质谱法(ICP-MS)在测定生物样品中的Hg时,由于Hg元素的电离能高、电离效率低,且存在W的氧化物等多原子离子干扰,很难进行直接准确测定,加之生物样品中有机质含量高,基体复杂,也会导致分析结果产生偏差。本文通过比较标... 电感耦合等离子体质谱法(ICP-MS)在测定生物样品中的Hg时,由于Hg元素的电离能高、电离效率低,且存在W的氧化物等多原子离子干扰,很难进行直接准确测定,加之生物样品中有机质含量高,基体复杂,也会导致分析结果产生偏差。本文通过比较标准模式(STD)和动能歧视模式(KED)下测定Hg的质谱干扰情况,表明在STD模式下200Hg、202Hg均受到W、Re、Os、Er、Dy等元素多原子离子的干扰,而KED模式有效地降低了干扰;在KED模式下选择202Hg作为分析同位素,Er、Dy、Re、Os等对Hg的干扰可以忽略不计,而W的氧化物干扰仍难以完全消除。进而详细研究了KED模式下W对Hg测定的质谱干扰,Hg所受干扰程度与W含量呈线性相关(R2=0.9997),可利用KED模式结合数学校正法消除W的质谱干扰;优选了样品稀释倍数和内标元素,选择稀释倍数为100倍,50μg/L的Rh作为内标补偿基体效应。在此基础上建立生物样品中Hg的ICP-MS分析与干扰校正方法,检出限为1.2ng/g。采用该方法对9个标准物质中Hg含量进行测定,测定值与标准值(或参考值)一致,尤其是国家标准物质GBW10028(黄芪)、GBW10025(螺旋藻)、GBW10015a(菠菜)的准确度显著提高,相对标准偏差(n=10)为0.7%~7.0%。该方法操作简便,适用于W含量范围在0~1000ng/g,Hg含量范围在3.2~670ng/g的生物样品的测试。 展开更多
关键词 生物样品 电感耦合等离子体质谱法 干扰校正
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A new kinetic spectrophotometric method for the determination of major metabolite of heroin in biological samples 被引量:2
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作者 M.Reza Shishehbore Ali Sheibani Ehsan Mirparizi 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第5期611-614,共4页
This study describes a simple,rapid and selective catalytic kinetic spectrophotometric method for the determination of 6- monoacetylmorphine(6-MAM) as major metabolite of heroin in biological samples.The method is b... This study describes a simple,rapid and selective catalytic kinetic spectrophotometric method for the determination of 6- monoacetylmorphine(6-MAM) as major metabolite of heroin in biological samples.The method is based upon the catalytic effect of 6-MAM on the oxidation of Janus Green by bromate in acid media.The reaction was followed spectrophotometrically by measuring the decrease in absorbance of Janus Green at 618 nm.The dependence of sensitivity on the reaction variables was studied.Under optimum conditions,two linear calibration curves over the range 0.1-1.0μg mL^(-1) and 1.0-34.0μg mL^(-1) of 6- MAM were obtained.The detection limit was 1.2×10~2μg mL^(-1) of 6-MAM.The relative standard deviations for six replicate determinations of 0.8 and 5.0μg mL^(-1) of 6-MAM were 1.4 and 1.1%respectively.The effect of various species commonly associated with heroin in real samples was also investigated.The proposed method was successfully applied in human urine and serum samples with satisfactory results. 展开更多
关键词 Heroin metabolite 6-Monoacetylmorphine Janus Green Kinetic spectrophotometric biological sample
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Current developments of bioanalytical sample preparation techniques in pharmaceuticals 被引量:3
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作者 Rahul G.Ingle Su Zeng +1 位作者 Huidi Jiang Wei-Jie Fang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第4期517-529,共13页
Sample preparation is considered as the bottleneck step in bioanalysis because each biological matrix has its own unique challenges and complexity.Competent sample preparation to extract the desired analytes and remov... Sample preparation is considered as the bottleneck step in bioanalysis because each biological matrix has its own unique challenges and complexity.Competent sample preparation to extract the desired analytes and remove redundant components is a crucial step in each bioanalytical approach.The matrix effect is a key hurdle in bioanalytical sample preparation,which has gained extensive consideration.Novel sample preparation techniques have advantages over classical techniques in terms of accuracy,automation,ease of sample preparation,storage,and shipment and have become increasingly popular over the past decade.Our objective is to provide a broad outline of current developments in various bioanalytical sample preparation techniques in chromatographic and spectroscopic examinations.In addition,how these techniques have gained considerable attention over the past decade in bioanalytical research is mentioned with preferred examples.Modern trends in bioanalytical sample preparation techniques,including sorbent-based microextraction techniques,are primarily emphasized. 展开更多
关键词 BIOANALYSIS biological matrices Matrix effect MICROEXTRACTION sample preparationtechnique
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