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101.
采用溶胶-凝胶技术将电子媒介体亚甲基蓝和辣根过氧化物酶(HRP)标记的癌胚抗原(CEA)固定在一次性丝网印刷碳电极表面,制备了CEA免疫传感器。该免疫传感器在含CEA样品的溶液中培育后,抗原-抗体免疫结合物的形成会阻碍HRP活性中心与亚甲基蓝之间的电子传递,使HRP对H2O2电催化氧化的效率降低。循环伏安和计时电流法用于研究免疫电极的电化学特性,在优化的条件下催化效率的降低与CEA质量浓度分别在1.0~6.0μg/L和6.0~138μg/L范围内成线性关系,检出限为0.4μg/L,测定的组内和组间相对标准偏差分别为7.4%和11.2%。该测定无须分离、洗涤步骤,分析时间短,操作方便,检测成本低,具有实际应用价值。 相似文献
102.
103.
纳米金修饰电流型CA19-9免疫传感器的制备及应用 总被引:3,自引:1,他引:3
通过固定辣根过氧化酶(HRP)标记CA19-9抗体在纳米金修饰的碳糊电极制备了CA19-9安培免疫传感器。该免疫传感器在舍有CA19-9抗原的磷酸盐缓冲溶液中培育后,溶液中CA19-9抗原分子和HRP标记CA19-9抗体分子免疫结合导致了传感器电流的降低。在优化的实验条件下,样品中CA19-9浓度在2~30U/mL范围内与电流降低成线性关系,方法的检出限为1.4U/mL。该免疫传感器表现出较好的稳定性、准确性和重现性,为临床免疫分析提供了一种快速便捷方法。 相似文献
104.
以氮杂环化合物为电化学分析底物的2-氨基-3-羟基吡啶-H2O2-辣根过氧化物酶(HRP)伏安酶联免疫体系测定人血清癌胚抗原(CEA).HRP催化H2O2氧化2-氨基-3-羟基吡啶的酶促反应产物,在缓冲液中-0.36 V处产生一个灵敏的伏安还原峰,借助此峰可以测定游离的HRP,进而可用于以HRP为标记物的酶联免疫分析.对酶促反应条件和测定条件的优化反应条件为:以B-R缓冲液(pH 6.0)为反应介质,在10 mL总反应液中含有1.0 mL 0.2 mol/L B-R缓冲液、3.0 mL 8.0 mmol/L 2-氨基-3-羟基吡啶溶液以及1.5 mL 0.5 mmol/L H2O2溶液,反应温度37 ℃,反应时间30 min.最佳测定条件为:B-R缓冲液(pH 7.0)为支持电解质,在10 mL总测定溶液中含有5 mL上述总反应液、1.0 mL 0.2 mol/L B-R缓冲液.测定仪器条件:起始电位0.00 V,终止电位-0.80 V,电位扫描速度400 mV/s,滴汞静止时间7 s.在最佳的反应条件和测定条件下,新体系测定游离HRP的线性范围为4.0×10-4~1.0 μg/L; 对HRP的检出限为0.12 ng/L.新体系对CEA测定的线性范围为0.50~80.0 μg/L; 检出限为0.50 μg/L.为经典ELISA法的检出限的1/10. 相似文献
105.
以饮食从业人员为检测对象.每人静脉采血5 mL,分离血清,应用ELISA方法进行检测.共检1 640人,HBsAg阳性96人,阳性率为5.85%(96/1640),其中HBsAg阳性血清进一步做HBeAg、抗-HBe、抗-HBc检测,阳性率分别为7.29%(7/96)、67.7%(65/96)、91.6%(88/96).其中男性722人,阳性62名,阳性率为8.59%(62/722),女性918人,阳性34名,阳性率为3.70%.HBsAg阳性率5.85%低于全国平均水平的8.08%.男性阳性率8.59%略低于我国1992年调查的11.3%,女性阳性率3.70%则明显低于我国同期调查的女性HBsAg阳性率8.23%. 相似文献
106.
活化高分子膜免疫电极检测乳腺癌抗原 总被引:4,自引:0,他引:4
报道了一种灵敏度高和使用简便的免疫电极,用于测定乳腺癌抗原(CA15-3)。CA15-3抗体固定在用羟胺活化的聚氯乙烯(PVC)-牛血清白蛋白(BSA)基体膜上。当抗体膜与CA15-3血清结合形成抗原体复合物膜后,将该复合物膜固定在自制Ag-AgCI基体电极顶端,利用毫伏计测定膜电位。该法可在15-240U/mL范围测定CA15-3,线性关系良好,回归方程:△E=-8、84 13、97Ig[CA15-3],相关系数0.9998。人血清中其他常见抗原对CA15-3测定基本无干扰。同时,探讨了免疫膜的电位响应机理。 相似文献
107.
108.
Man Fan Le Jia Minghui Pang Xiangliang Yang Yajiang Yang Samir Kamel Elyzayati Yonggui Liao Hong Wang Yanhong Zhu Qin Wang 《Advanced functional materials》2021,31(20):2010587
Low vaccine immunogenicity and tumor heterogenicity greatly limit the therapeutic effect of tumor vaccine. In this study, a novel injectable adhesive hydrogel, based on thermosensitive nanogels containing catechol groups and loaded with in situ-forming MnO2 nanoparticles, is constructed to overcome these issues. The concentrated nanogel dispersion transforms into an adhesive hydrogel in situ after intratumoral injection. The photothermal effect of the loaded MnO2 nanoparticles induces immunogenic cell death to release mass autologous tumor-derived protein antigens under near-infrared irradiation, which act as ideal immune stimulating substances avoiding the problem of tumor heterogenicity and are captured by the in situ-forming adhesive hydrogel. The antigens-captured adhesive hydrogel acts as an “antigen reservoir” and releases these captured antigens to recruit more dendritic cells to stimulate an intensive and lasting anti-tumor immune response mediated by CD8+ T cells. The primary tumors can be almost completely disappeared within 4 days without relapse, and the growth of the distal tumors and rechallenged tumors are also effectively inhibited by the treatment with the injectable adhesive hydrogel-based photothermal therapy. Therefore, the proposed “antigen reservoir” strategy shows the great potential application as an in situ-forming personalized vaccine to enhancing the cancer immune therapy. 相似文献
109.
《Electroanalysis》2018,30(5):852-858
In this study, a novel signal‐amplified strategy for sensitive electrochemical sandwiched immunoassay of carcinoembryonic antigen (CEA) was constructed based on aminofunctionalized graphene oxide (GO‐NH2) supported AgNPs used as catalytic labels of secondary anti‐CEA and β‐galactosidase (β‐Gal), Meanwhile, sulfhydrylation single‐wall carbon nanotubes (SWCNTs‐SH) as substrate materials embellished gold electrode through Au‐SH and connected with gold nanoparticles to form anti‐CEA/AuNPs/SWCNTs‐SH/Au sensing platform through layer‐by‐layer. In the presence of analyte CEA, a sandwich‐type immunoassay format was employed for determination of CEA by using the labeled β‐Gal toward the reduction of p‐aminophenyl galactopyranoside (PAPG) and the redox reaction of AgNPs. Under optimal conditions, the increase in the current was proportional to the concentration of CEA from 0.1 pg/mL to 200 ng/mL. The detection limit (LOD) was 0.036 pg/mL CEA at 3σ. The electrochemical immunoassay displayed an acceptable precision, selectivity, stability. Clinical serum specimens were assayed with the method, and the results were in acceptable agreement with those obtained from the referenced electrochemiluminescent method. 相似文献
110.
《Electrophoresis》2017,38(3-4):408-416
Serum levels of Prostate‐Specific Antigen (PSA) are not fully specific for prostate cancer (PCa) diagnosis and several efforts are focused on searching to improve PCa markers through the study of PSA subforms that could be cancer associated. We have previously reported by 2DE a decrease in the sialic acid content of PSA from PCa compared to benign prostatic hyperplasia patients based on the different proportion of the PSA spots. However, faster and more quantitative techniques, easier to automate than 2DE, are desirable. In this study, we examined the potential of CE for resolving PSA subforms in different samples and compared the results with those obtained by 2DE. We first fractionated by OFFGEL the subforms of PSA from seminal plasma according to their pI s and analyzed each separated fraction by 2DE and CE. We also analyzed PSA and high pI PSA, both from seminal plasma, and PSA from urine of a PCa patient. These samples with different PSA spots proportions by 2DE, due to different posttranslational modifications, also presented different CE profiles. This study shows that CE is a useful and complementary technique to 2DE for analyzing samples with different PSA subforms, which is of high clinical interest. 相似文献