A multianalyte ELISA for immunochemical screening of sulfonamide,fluoroquinolone and ß-lactam antibiotics in milk samples using class-selective bioreceptors

A multianalyte ELISA has been developed for the simultaneous determination of the most frequently used antibiotic families in the veterinary field following the typical planar microarray configuration, where the identity of the target analyte is encoded by its location in the detection platform (Master et al. in Drug Discovery Today 11:1007-1011, 2006). To accomplish this aim, two individual enzyme-linked immunosorbent assays for sulfonamide and fluoroquinolone antibiotics and an enzyme-linked receptor assay for ss-lactam antibiotics have been combined. The strategy uses microplates coated with the corresponding haptenized proteins in specific sections of the microplate. The samples are mixed with a cocktail containing the bioreagents, and distributed in the wells of the microplate. Identification of the antibiotic present in a particular sample is consequently accomplished by detecting a positive response on the corresponding microplate section. Since the bioreceptors used show a wide recognition of the congeners of each antibiotic family, the multianalyte method is able to detect more than 25 different antibiotics from the three most important antibiotic families. The detectability reached in full-fat milk samples is below the European maximum residue limits. The accuracy and reliability of this multiplexed bioanalytical method have been demonstrated by analyzing blind spiked samples.     

Self‐Assembled Colloidal Particle Clusters from In Situ Pickering‐Like Emulsion Polymerization via Single Electron Transfer Mechanism

A simple route is reported to synthesize colloidal particle clusters (CPCs) from self‐assembly of in situ poly(vinylidene fluoride)/poly(styrene‐co‐tert‐butyl acrylate) [PVDF/P(St‐co‐tBA)] Janus particles through one‐pot seeded emulsion single electron transfer radical polymerization. In the in situ Pickering‐like emulsion polymerization, the tBA/St/PVDF feed ratio and polymerization temperature are important for the formation of well‐defined CPCs. When the tBA/St/PVDF feed ratio is 0.75 g/2.5 g/0.5 g and the reaction temperature is 35 °C, relatively uniform raspberry‐like CPCs are obtained. The hydrophobicity of the P(St‐co‐tBA) domains and the affinity of PVDF to the aqueous environment are considered to be the driving force for the self‐assembly of the in situ formed PVDF/P(St‐co‐tBA) Janus particles. The resultant raspberry‐like CPCs with PVDF particles protruding outward may be promising for superhydrophobic smart coatings.

     

化学发光单孵多层免疫技术检测粪样中轮状病毒

以酶联免疫吸附分析（ＥＬＩＳＡ）夹心测定粪样中轮状病毒（ＲＶ）实验为模型，将传统又孵式免疫操作变成单孵式，即在包被ＲＶ抗体Ａｂ的微孔中同时加入含ＲＶ的粪样上清液和根过氧化物酶（ＨＲＰ）标记抗ＲＶ抗原共同孵育，其结果在载体表面形成多层酶免疫复合物，以ＨＲＰ催化鲁米诺－对碘苯酚－过氧化氢化学体系作为最终信号检测系统，从而建立起化学发光单孵多层免疫技术（ＣＬ－ＳＩＭＩＴ）。其灵敏度是ＥＬＩＳＡ的１６倍，     

Fracture mechanisms in rigid core-shell particle modified high performance epoxies

The fracture mechanisms of a high performance epoxy system modified with two types of preformed rigid core-shell particles (RCSP) were investigated. The use of the preformed RCSP anables the control of the dispersion of the toughener phase in the epoxy, which, in turn, allows the mechanical properties of the modified epoxy to be optimized. The toughening effect via the RCSP modification is found to be as good as that via the core-shell rubber modification. The moduli andT _g of these RCSP-modified epoxies are virtually unaltered via the RCSP modification, when compared with the neat epoxy resin equivalent. The toughening mechanisms in these toughened systems appear to be predominantly crack deflection, crack bifurcation, and microcracking. Approaches for effective toughening of high performance polymers via rigid polymers are discussed.     

PS胶体粒子表面逐层自组装固定化SOD及其生物活性

通过逐层自组装技术成功地把超氧化物歧化酶(SOD)吸附在聚苯乙烯(PS)胶体粒子表面.zeta电位和TEM证明了聚阳离子或聚阴离子型SOD与相反电荷的聚电解质在PS胶体粒子表面的交替吸附.通过测定SOD被胶体粒子吸附后上清液的生物活性,得到聚阴离子型SOD(pH=8.0)和聚阳离子型SOD(pH=4.3)在PS胶体粒子表面的吸附量分别为12和51IU,相对活性分别为23.4%和2.9%.聚阴离子型SOD在PS胶体粒子表面能形成平滑规整的膜,导致较高的相对活性.研究结果表明,通过调节pH值,可以优化自组装固定化酶的聚集状态和生物活性     

二氧化硅胶体晶体及其为模板的多孔材料

用Stober法合成了粒径在35～750nm范围内的单分散的SiO₂粒子,考察了投料比对粒径的影响.研究了所制备的SiO₂胶体晶体的结构和反射光谱.利用两种不同粒径的SiO₂粒子作为模板和模板填充物,分别制备了SiO₂和重氮树脂的多孔材料.     

荧光光谱法测定水泥中硫酸根含量

0．1mol／LHCl—4．0mg／mL TX-100—0．05mol／LBaCl2溶液体系的荧光很弱,加入SO4^2-后形成的(BaSO4)。微粒在410nm、470nm处产生2个荧光峰,SO4^2-浓度在2．0～80μg／mL浓度范围内与F470呈线性关系．据此建立了一个测定水泥样品中硫酸根的简便灵敏的荧光光谱分析新方法,其相对偏差(RSD)在1．90%-3．9％之间,回收率在97．0％～102％之间．     

紫外光照射下ZnO超微粒子表面上的光反应

由于半导体超微粒子具有独特的尺寸量子化效应和表面效应^[1~6],它在利用太阳能光催化降解有机污染物,有机光合成及光电转化等领域中有着极其广泛的应用.目前,大量的工作集中在超微颗粒表面上有机物的光反应过程的研究^[7].     

Influence of Solvent Size on Structural Properties of Bottle-brush Polymers

We proposed a modified dissipative particle dynamics simulation model by which one can effectively avoid the bond-crossing problem, and investigated the effect of solvent size on the structural properties of bottle-brush polymers in dilute solution on the basis of this model. It was found that with the increase of solvent size, the radius of the gyration of the bottle-brush polymer decreases considerably in the athermal solvent but increases in the selective solvent favoring the backbone, respectively.