农药甲胺磷人工抗原的光谱鉴定研究

对农药甲胺磷人工抗原BSAM的光谱进行了鉴定 ,鉴定结果表明 :人工抗原BSAM的紫外光谱图与原载体和半抗原的紫外光谱相比均发生变化 ;人工抗原BSAM的红外光谱图上具有与甲胺磷分子相似的P—O—C和PO特征吸收峰 ;人工抗原BSAM具有与标准甲胺磷一致的3 1 PNMR化学位移峰 ,磷钼蓝分光光度法测定人工抗原BSAM中的磷浓度后计算出人工抗原BSAM的偶联率为 1 1。4种光谱方法测定结果综合表明甲胺磷人工抗原BSAM合成成功。     

Simple fabrication of a smart microarray of polystyrene microbeads for immunoassay

We describe a simple method to fabricate an array of polystyrene microbeads (PS μbeads) conjugated with an elastin-like polypeptide (ELP) on a glass surface using a removable polymer template (RPT). A thin layer of adhesive was spun-cast on glass and cured by UV radiation. Micropatterns of an RPT were then transferred onto the surface by microcontact printing. The adhesion of PS μbeads on the surface depended on the adhesion performance of the adhesive layer, which could be adjusted by irradiation time. An array of PS μbeads conjugated with ELP was used for a smart immunoassay of prostate-specific antigen (PSA), a cancer marker. By controlling the phase transition of ELP molecules, PSA molecules were selectively adhered or released from the bead surface. The selective and reversible binding of PSA molecules on the bead surface was characterized with fluorescence microscopy.     

Prostate-specific antigen immunoassays on the BioCD

The BioCD is a spinning-disc interferometric biosensor on which antibodies are immobilized to capture target antigens from biological samples. In this work, BioCDs measured the interferometric response to prostate-specific antigen (PSA). The ideal detection limit for PSA was determined using a BioCD with 12,500 printed target antibody spots with a corresponding number of reference protein spots. Statistical analysis projects the detection limit of PSA as a function of the number of spots included in the average. When approximately 10,000 spot pairs were averaged, the 3σ detection limit was 60 pg/ml in a 2 mg/ml simple protein background. A standard format for BioCD immunoassays uses 96 wells with 32 target spots paired with reference spots. In serum, the detection limit for this format was 1 ng/ml in 3:1 diluted female human serum using a sandwich assay with a nonfluorescent mass tag.     

生物分子膜门电极AlGaN/GaN高电子迁移率晶体管(HEMT)生物传感器研究

设计并制作了结构尺寸为毫米量级的AlGaN/GaN高电子迁移率晶体管(HEMT)生物传感器,采用数值分析的方法分析了器件传感区域长度与宽度比值及待测物调控二维电子气(2DEG)距离与感测信号之间的关系,给出了结构尺寸为毫米量级的AlGaN/GaN HEMT生物传感器的设计依据,以不同浓度的前列腺特异性抗原(PSA)为待测物,对制作的AlGaN/GaN HEMT生物传感器进行了初步测量,测试结果表明,在50 mV的电压下,毫米量级的AlGaN/GaN HEMT生物传感器的对PSA的探测极限低于0.1 pg/ml.实验表明毫米量级的AlGaN/GaN HEMT生物传感器具有灵敏度高,易于集成等优点,具备良好的应用前景.     

Studies on Carbohydrates ⅩⅩⅧ. Synthesis of Key Intermediates of Oligosaccharides Related to Serratia marcescens O10 Antigen

TheO-antigenofbacteriacanbeusedasahaptenandvaccine.Preparationofanantigeninv0lvesthesynthesisofacorrespondinghaPtenbearingeithernarrow0rwiderspeci-ficity.Generally,fragmentsofcarbohydratechainsbearingthes0-calledcompleterepeatingunitareemployedashaPtens.Synthesis0foligosaccharides,whichareveryspecificfragments,isatpresentoneoftheimP0rtantaspectsofcarb0hydratechemistry.TheS.marcescensOlOantigenhasbeenisolatedfromtheLPSofthereferencesKain(C.D.C.l287-54)ofS.marcescens.Itsbiol0gicalrepeatun…     

Selective response of antigen‐antibody reactions on chiral surfaces modified with 1,2‐diphenylethylenediamine enantiomers

This work reported a comparative analysis of the amperometric responses of antigen‐antibody reactions on two stable chiral surfaces which were modified with 1,2‐diphenylethylenediamine enantiomers. Alpha‐fetoprotein antibody and antigen (anti‐AFP and AFP) were selected as model systems. First, (1R,2R)‐1,2‐diphenylethylenediamine or (1S,2S)‐1,2‐diphenylethylenediamine was modified on the gold surface of the electrode through amide linkage to construct chiral surfaces. Then, anti‐AFP was immobilized on the chiral electrode surface by electrostatic and hydrogen bonding interactions. The electrochemical characteristics of the modified electrodes were studied via cyclic voltammetry. The selective current responses of antigen‐antibody reactions on chiral electrode surfaces for different incubation time and varying AFP concentrations were monitored. The antigen‐antibody reactions were greatly influenced by the chirality of 1,2‐diphenylethylenediamine enantiomers, and the amperometric responses obtained from the (1S,2S)‐1,2‐diphenylethylenediamine modified electrode was obviously stronger than that from the (1R,2R)‐1,2‐diphenylethylenediamine modified electrode. Such work may not only offer valuable reference to the research of chiral drugs, but also help to comprehend the high selectivity of chiral molecular species in biosystems. Copyright © 2011 John Wiley & Sons, Ltd.     

Detection of Aryloxyphenoxypropionate Herbicides by Enzyme-Linked Immunosorbent Assay

In this study, we developed a general and broad class-selective indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for detecting aryloxyphenoxypropionate herbicides. A multideterminant artificial antigen was prepared from haptens of two herbicides (fenoxaprop-p-ethyl and cyhalofop-butyl) conjugated to the carrier protein Bovine serum albumin (BSA). The polyclonal antibodies (PAbs) were obtained by immunizing New Zealand white rabbits. Characterization studies of the PAbs showed that they had high affinity and specificity for the two herbicides. The 50% inhibitory concentration (IC₅₀) values for fenoxaprop-p-ethyl and cyhalofop-butyl were 0.185 mg L^?1 and 0.045 mg L^?1 with a limit of detection (LOD, IC₁₀) of 0.004 mg L^?1 and 0.002 mg L^?1, respectively. There were no obvious cross-reactivities with most of the aryloxyphenoxypropionates tested, except for metamifop (CR% = 55.56%). The recoveries of fenoxaprop-p-ethyl, cyhalofop-butyl and metamifop in environmental and agricultural samples (tap water, paddy water, soil, rice and soybean) ranged from 86.86–114.52%, 82.07–119.11% and 82.51–114.46%, respectively. These results demonstrate that the established ELISA could be used as a tool for detecting aryloxyphenoxypropionate multiresidues.     

Amperometric Immunosensor for Prostate Specific Antigen Based on Gold Nanoparticles/Ionic Liquid/Chitosan Hybrid Film

The hybrid film of gold nanoparticles/ionic liquid-chitosan (GNP/IL-Ch) was first prepared by a simple one-step synthesis and used as an efficient immobilization matrix to fabricate an immunosensor. The GNP/IL-Ch film not only prevents the leakage of the IL units, but also produces a well-defined voltammetric signal due to the synergistic effects of the IL units and GNPs. By immobilizing an alkaline phosphatase (ALP)-labeled antibody in GNP/IL-Ch film, a sensitive amperometric immunosensor has been developed for prostate specific antigen (PSA). Under the optimized conditions, the immunosensor exhibits a linear range from 1.0 to 80 ng mL^?1 of PSA.     

Inhibition of Salidroside on Salivary Gland Adenoid Cystic Carcinoma

To evaluate the role of salidroside on proliferation,apoptosis and invasiveness of salivary gland adenoid cystic carcinoma cells(SACC),immunocytochemical staining was employed to detect proliferating cell nuclear antigen(PCNA),caspase 3 and caspase 8 expression in SACC-2 cells.Modified Boyden chamber assay combined with laser confocal microscopy(LSCM) was used to evaluate the invasion and migration abilities of SACC-2 cells at different time point.Immunohistochemistry staining revealed that the expression of PCNA was significantly decreased(P0.01) after salidroside treatment.In contrast,salidroside treatment led to increased caspase 3 and caspase 8 in SACC-2 cells.Cell migration depth and number of cells that penetrated Boyden chamber were also decreased by salidroside.Salidroside potently inhibits the proliferation and simultaneously induces the apoptosis of SACC-2 cells.Migration and invasion of SACC-2 cells are also inhibited.Our data throw light on potential clinical application of salidroside to the patients with SACC.     

乙型肝炎病毒表面抗原三维结构的同源模建及功能预测

结合生物信息学方法及分子模拟手段, 通过同源模建方法构建了乙型肝炎病毒表面抗原(HBsAg)Pres12的三维空间结构, 并结合生物实验在分子水平上探讨了乙型肝炎病毒表面抗原Pres12作为抗乙型肝炎病毒重要靶标的机理. 研究结果表明, HBsAg三维空间结构是由构型性的Pres1和线性的Pres2组成, 此结构由疏水氨基酸形成3个α-螺旋结构及Loop结构域, 并且N端由Pres1中残基构成了一个开裂, 形成了HBsAg可能的活性部位. 静电势分析结果证实, N端可能的活性部位具有较大的静电势分布, 因而具有与受体细胞蛋白相互作用的能力, 这为HBV病毒抑制剂药物分子的设计提供了有益帮助.