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1.
研究了醇氧化酶-过氧化氢酶联合的酶促反应的最佳条件,建立了简便测定乙醇的吸光光度法,乙醇浓度在0.0686~5.115 mmol/L范围内符合比尔定律,回归方程为:A=0.00403 0.08585c(mmol/L),相关系数为0.9986,检出限为0.0172 mmol/L(S/N=3),本法所用仪器简单,已用于酒后唾液中乙醇的测定。  相似文献   

2.
唾液中葡萄糖含量与血糖水平密切相关,可通过非侵入式采集、测定实现血糖的持续、准确监控.但唾液中葡萄糖含量极低,干扰组分众多,对分析方法的选择性、灵敏度、样品用量、响应时间等都提出更严苛的要求.本文通过戊二醛交联法在氨基化磁性微球上固定葡萄糖氧化酶(GOx)和辣根过氧化物酶(HRP),利用微流控磁载技术将磁性微球富集在微...  相似文献   

3.
对人体血液、尿液、唾液及呼出气体中乙醇含量检测方法进行综述。顶空气相色谱法适用于检测血液和尿液中的乙醇含量,精度高,稳定性好;乙醇氧化酶法在检测乙醇含量时有操作简单使用方便的特点;利用电化学原理或红外原理检测呼出气体中酒精含量时,可以实现定性、定量分析,仪器操作简单、稳定性好、体积小。对乙醇检测仪器和装置的溯源方法进行总结,国家有证标准物质的研制以及乙醇气体发生源装置的建立确保了检测结果的量值准确和单位统一。  相似文献   

4.
5.
快速检测甲胎蛋白的免疫层析试条的研制   总被引:4,自引:0,他引:4  
研制了可简便、快速检出原发性肝癌标志物--人血清中甲胎蛋白(AFP)的免疫层析试条。为此,研究了用国产试剂和材料制备胶体金、用此胶体金标记抗AFP单抗的影响因素以及抗AFP抗体固化条件、抗AFP抗体与其AFP结合能力等。结果表明,自制国产胶体金质量不亚于进口商品;金标单抗和固化抗体活性稳定,能分别显示出结合AFP分子不同表位的特异性。所得检测试条的检出速度在5至20min内,检测阳性阈值定为20ng AFP/mL血清。  相似文献   

6.
TCS(2,4,4’-三氯-2’-羟基二苯醚,triclosan,中文名称玉洁纯、玉洁新、三氯新等),是一种非离子型的高效广谱抗微生物剂,对于一般常见的细菌、真菌及酵母等病原菌都具有杀灭功效及抑制作用,广泛用于牙膏、洗漱液和洗发液中。国内外学者长期的临床观察证实含有TCS的牙膏和漱口水能有效地控制菌斑和缓解牙龈炎症状。  相似文献   

7.
开发成功了一种能快速、灵敏、高特异性检测疟疾的免疫层析试条。选自恶性疟原虫富组蛋白Ⅱ-一级结构中的九肽(AHHAHHAAD),经人工合成后作为免疫原,生产了一些单表位单抗;完成了一些单抗的纯化与鉴定;制取了金标单抗并对其吸收光谱进行了分析;选取了包被单抗和金标单抗间的配对;比较了影响检测的各种因子。当用此试条检测62名已用常规血间检法确证患有疟疾个体的全血,准确率达93.54%。  相似文献   

8.
硫堇-甲苯二异氰酸酯衍生物修饰的玻碳基乙醇传感器的研究俞爱民,韩吉林,杨可盛,陈洪渊(南京大学化学系,南京,210093)关键词硫堇-TDI衍生物,NAD~+,ADH,乙醇传感器经典的测定乙醇含量的方法有气相色谱法[1]、分光光度法[2].近年来,随?..  相似文献   

9.
根据竞争法免疫层析试条的检测原理,本研究将其分为TwA和TnA两种模式,结合对流扩散方程分别建立其数学模型,并运用COMSOL软件对试条的动态反应过程进行仿真,得到检测线和质控线上各复合物浓度关于各影响因素的关系曲线.在TwA模式中,分析了待测物浓度[A0]=0~20 mol/L,标记物浓度[P0]=0.01~100 mol/L,检测线位于5~20 mm位置等因素对于检测结果的影响;在TnA模式中,分析了[A0]=0~20 mol/L, [P0]=0.01~100 mol/L, [A0]和[P0]两种物质浓度及孔隙率等因素对于检测结果的影响.结果表明,本研究建立的竞争法模型与仿真能探究各参数对于检测结果的影响,优化试条性能,从而提高试条检测灵敏度和实现定量检测.  相似文献   

10.
《分析试验室》2021,40(9):1021-1025
以铂丝(Pt)为正极、银片为负极制备了柱状电极探头,经超声纳米雾化喷涂氧化石墨烯,构建了一种纳米颗粒修饰的新型柱状电极。利用酶固定化技术,在柱状电极探头表面直接固定乙醇氧化酶,制成乙醇直接酶电极,并用于检测乙醇含量。结果表明,乙醇检测时间为12 s;在p H 2~11,温度范围为15℃~40℃;线性范围为0.01~2 mg/mL,检测限为10μg/mL;重复测定相对标准偏差(RSD) 0.7%;首次定标调试后,再次开机时不需要重复定标,33 d内酶电极活性扔保持稳定,RSD为1.1%。加标回收率范围99.3%~101%。方法用于血浆乙醇含量检测时,测定结果与气相色谱法无明显差异。该方法可用于现场在线测定。  相似文献   

11.
建立了气相色谱法(GC)同时检测人唾液中7种短链脂肪酸(Short-chain fatty acids,SCFAs)含量的方法.唾液样品与乙醇溶液按体积比1∶1混合(含0.5% (v/v)浓HCl)涡旋混合,离心后取上清液进行GC分析.采用DB-FFAP毛细管柱(30 m×0.25 mm×0.25 μm)进行分离;氢火焰离子化检测器(FID)进行检测,内标法定量.实验结果表明,唾液中共检测到7种SCFAs(乙酸、丙酸、异丁酸、丁酸、异戊酸、戊酸、己酸),7种SCFAs与内标物2-乙基丁酸的色谱峰峰面积比值与其浓度均呈现良好的线性关系(R2≥0.999),检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.060~0.198 μg/mL和0.180~0.594 μg/mL,平均加样回收率为94.8%~ 109.7%(RSD≤4.3%).本方法简单、快速、准确,可用于测定人的唾液中短链脂肪酸的含量.  相似文献   

12.
Saliva opens a door for noninvasive and painless glucose testing since it reflects changes in the body physiology of diabetic individuals as compared to healthy ones. In this paper, a unique, disposable saliva biosensor has been developed for accurate, low cost, and continuous glucose monitoring. The biosensor exhibits linear dependence of the catalytic current upon glucose bulk concentration over the 0.05–1.5 mM range (R=0.998). A detection limit of 0.003 mM can be calculated considering three times the standard deviation of the blank signal divided by the sensitivity of the sensor. The selectivity of the biosensor was evaluated by adding the interferent species of lactate, ascorbic acid and uric acid into in 0.5 mM glucose; the nearly negligible interference current indicates its good selectivity. The operational stability of the biosensor was measured in 1 mM glucose over a 2 h period (RSD=3.27 %). A clinical trial on real‐time noninvasive salivary glucose monitoring was carried out on 30 individuals by measuring subjects’ salivary glucose and blood glucose in parallel. The results show that there is a good correlation of glucose levels in saliva and in blood 2 h after breakfast. Thus, the disposable biosensor would be a potential alternative for continuous glucose detection in human saliva.  相似文献   

13.
《Analytical letters》2012,45(17):2549-2561
Caffeine is a useful indicator to quickly assess liver function. High-throughput tests are needed for single-point caffeine measurements, with low cross-reactivity toward its major metabolite, paraxanthine. A newly developed ELISA was compared with an LC-MS/MS reference method, using 60 saliva samples from 10 individuals, before and after caffeine intake. Bland-Altman plot, Student t-test and F-test were used to compare the two methods. Proteins were precipitated using organic solvent and the caffeine recoveries compared with those obtained using sample microfiltration. The antibody, with a low cross-reactivity toward paraxanthine (0.08%), allows quantification of caffeine in saliva samples from 2.5 µg/L to 125 µg/L with high precision and the ELISA shows comparable results to those obtained by LC-MS/MS. A one-step protein precipitation using an organic solvent provides comparable results to a more costly and time-consuming microfiltration pre-treatment of samples. The new ELISA is a fit-for-purpose method to accurately and precisely determine caffeine in saliva samples.  相似文献   

14.
Amplified ATP imaging in inflammatory cells is highly desirable. However, the spatial selectivity of current amplification methods is limited, that is, signal amplification is performed systemically and not in a disease site-specific manner. Here we present a versatile strategy, termed enzymatically triggerable, aptamer-based signal amplification (ETA-SA), that enables inflammatory cell-specific imaging of ATP through spatially-resolved signal amplification. The ETA-SA leverages a translocated enzyme in inflammatory cells to activate DNA aptamer probes and further drive cascade reactions through the consumption of hairpin fuels, which, however, exerts no ATP response activity in normal cells, leading to a significantly improved sensitivity and spatial specificity for the inflammation-specific ATP imaging in vivo. Benefiting from the improved spatial selectivity, enhanced signal-to-background ratios were achieved for ATP imaging during acute hepatitis.  相似文献   

15.
《Analytical letters》2012,45(11-12):2471-2483
Abstract

A method to eliminate human chorionic gonadotropin (hCG) in the sandwich enzyme immunoassay for human thyroid-stimulating hormone (hTSH) in serum is described. hTSH in serum containing hCG was reacted with dinitrophenyl monoclonal mouse anti-hTSH β-subunit IgG1, and the complex formed between the dinitrophenyl IgG1 and hTSH was trapped onto affinity-purified rabbit (anti-dinitrophenyl bovine serum albumin) IgG-coated polystyrene balls. hCG in the test serum was largely eliminated by washing the polystyrene balls. Subsequently, the complex on the polystyrene balls was reacted with affinity-purified rabbit anti-hCG Fab′-peroxidase conjugate followed by washing. The complex of the dinitrophenyl IgG1, hTSH and the conjugate was eluted with dinitrophenyl-L-lysine from the polystyrene balls, to which hCG had been nonspecifically adsorbed, and was trapped onto clean polystyrene balls coated with affinity-purified rabbit (anti-mouse IgG) IgG. Peroxidase activity bound to the (anti-mouse IgG) IgG-coated polystyrene balls in the absence and presence of hTSH was not significantly affected by the presence of up to 75,000 IU of hCG per liter of serum. As a result, serum hTSH could be sensitively measured with little interference by hCG.  相似文献   

16.
张帆  李庆阁 《分析化学》1993,21(6):698-700
应用活化鲁米诺,用优化的增强化学发光酶联免疫分析体系测定人绒毛膜促性腺激素,检测限为0.2mIU/ml。线性范围0~200mIU/ml,与放射免分析测定结果比较,相关性良好。进而又发展了一种半定量的照相测定法,通过实际血清样品测定,效果良好。  相似文献   

17.
《Analytical letters》2012,45(7):1093-1108
Abstract

To overcome the IgA interference in enzyme immunoassay for serum secretory IgA (SIgA), a new specific, simple and more sensitive sandwich enzyme immunoassay, fully free of the serum IgA interference, was developed. SIgA standards or samples were added into the wells of polystyrene plate coated with rabbit IgG antibody to human secretory component. After incubation, the wells were washed and then, horseradish peroxidase-labeled Fab′ fragment of goat IgG antibody to human α-chain was added and incubated. The wells were washed again to remove the unbound labeled antibody, and the enzyme activity specifically bound to the well was assayed using 3,3′, 5,5′ - tetramethylbenzidine and H2O2 as substrate. The enzyme reaction was stopped by addition of 2M H2SO4. The SIgA concentration was determined from the absorbance at 450 nm. The minimun detectable sensitivity was 6ng/ml. The assay system had very good selectivity overcoming the interference of IgA. As the result of high sensitivity, only small amount of sample (2 μ1 for serum) was needed for analysis. In this assay, no cross reactivity was found with purified human IgG, mIgA, IgM or free secretory component (FSC). The recovery of SIgA mixed with human sera or biles was 99.6–108.1%. The coefficients of within-assay and between-assay variation were 5.8–9.3% and 6.2–9.2% respectively. It correlated well with a liquid phase competitive radioimmunoassay for human serum SIgA (r=0.96, n=30, P<0.0l). The level of SIgA in normal human serum was 8.04±3.60 (SD) μg/ml (n=117) and increased significantly in patients with choledocho- lithiasis (57.35±49.70 μg/ml, n=15, P<0.0l). SIgA concentrations in bile samples were also determined by the 2 4′ assay under the condition that FSC did not, interfere with the assay.  相似文献   

18.
POAP-Ni2+膜电极对乙醇氧化表现出优越的电催化活性.乙醇氧化电流受到膜厚、膜中镍离子浓度、活化时间、电解质pH值及温度等条件的影响.选择合适的条件,可得到乙醇浓度与响应电流的线性关系.POAP-Ni2+可构成较理想的乙醇传感器,其线性范围、检测下限、响应时间及抗干扰能力等主要特征参数均达到实用要求  相似文献   

19.
An electrochemical immunosensor for ghrelin (GHRL) determination in saliva is reported. Anti‐GHRL was immobilized onto Protein G‐magnetic beads and a competitive immunoassay involving biotinylated GHRL and alkaline phosphatase‐streptavidin was implemented. Once conjugate was magnetically captured on a screen‐printed carbon electrode, GHRL quantization was accomplished by DPV of 1‐naphtol formed upon addition of 1‐naphtyl phosphate. A linear range between 10?3 and 103 ng/mL GHRL, and a LOD of 7 pg/mL, much smaller than those from commercial ELISA kits, were found. The usefulness of the immunosensor was demonstrated by analyzing human saliva spiked with GHRL at 0.01, 0.1, 1 and 10 ng/mL.  相似文献   

20.
一种可回收循环使用的磷钨杂多酸盐(n-C_(16)H_(33)N(CH_3)_3)_3[PW_4O_(16)])应用于醇类的无溶剂催化氧化反应.通过IR和~(31)PNMR光谱对醇氧化反应前后以及反应过程中催化剂的结构变化进行表征分析,得出此催化剂为多种磷钨杂多酸盐的混合物,反应中活性中间体为含活性氧物种,多次反应-分离循环后催化剂活性会逐渐降低,催化剂的结构逐渐变为稳定的keggin结构.  相似文献   

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