Prototype of immunochromatographic assay strips using colloidal CdTe nanocrystals as biological luminescent label

Colloidal semiconductor nanocrystals have attracted considerable attention as a novel biological luminescent label. The bioinorganic conjugates of luminescent CdTe nanocrystals and protein, including CdTe/BSA (bovine serum albumin) and CdTe/MAB (mouse monoclonal antibody against hepatities B surface antigen), were formed via electrostatic/coordination self-assembly. Pure CdTe nanocrystals, CdTe/BSA and CdTe/MAB were used in the immunochromatographic assay experiments, respectively. And the results indicated that CdTe nanocrystals could be used and developed as a novel label with good stability, high sensitivity and facile determination of several analytes in immunochromatographic assay strips.     

O-二异丙氧磷酰基丝氨酸(或苏氨酸或酪氨酸)的合成

介绍一种简单方便地合成O-二异丙氧磷酰基丝氨酸(或苏氨酸或酪氨酸)的方法.其中O-二异丙氧磷酰基-L-丝氨酸(或苏氨酸)可从对应的N-磷酰化-L-丝氨酸(或苏氨酸)利用磷酰基N→0迁移的性质并在超声辅助下合成,而N-二异丙氧磷酰基-L-丝氨酸(或苏氨酸)的合成由L-丝氨酸(或苏氨酸)在次氯酸钠的水溶液中高收率地获得.O-二异丙氧磷酰基酪氨酸的合成可通过铜盐同时保护氨基和羧基,使用二异丙基磷酰氯为磷酰化试剂磷酰化,用硫化氢脱铜保护制备.     

实时荧光等位基因特异性扩增法快速检测K-ras癌基因点突变

将荧光定量PCR技术与等位基因特异性扩增(Allele specific amplification, ASA)方法相结合, 发展了一种可以快速检测基因点突变的实时荧光等位基因特异性扩增(Real-time ASA)方法. 将该法用于检测K-ras癌基因第12位密码子发生的点突变, 分别采用针对其不同点突变方式(GAT, GTT, CGT)设计的突变型引物对待测样品进行ASA, 只有突变型样品能被顺利扩增出双链DNA产物, 该产物才能与双链DNA染料SYBR Green Ⅰ结合, 发出荧光信号从而被检测到. 用该法检测31例结肠癌组织中的K-ras癌基因点突变, 其中有15例样品检出为突变型. Real-time ASA法可检测到样品中含量为1/1000的突变型基因, 具有灵敏、快速、简便、安全、高通量和低成本等优点, 可望用于大量临床样本的点突变筛查.     

Preparation, characterization and properties studies of quinine-imprinted polymer in the aqueous phase

The uniform-sized spherical molecularly imprinted polymers were successfully prepared through molecular imprinting technology by two-step seed swelling and mini-emulsion polymerization in the aqueous condition using quinine as template molecules and methacrylic acid (MAA) as functional monomer. The polymers were characterized by IR spectra, thermal-weight analysis, scanning electron microscope and laser particle size analysis. The properties of imprinted polymers were investigated in different organic phases and aqueous media. In the organic media, results suggested that polar interactions (hydrogen bonding, ionic interactions) between acidic monomer/polymer and template molecules are mainly responsible for the binding and recognition; whereas in the aqueous medium, a considerable recognition effect was also obtained where the ionic (electrostatic) interaction and hydrophobic interaction play an important role. The experiments of binding different substrates indicated that the MIPs possessed an excellent rebinding ability and inherent selectivity to quinine. __________ Translated from Zhongshan Dcocue Xuebao/Acta Scientianum Natralium University Sunyatseni, 2005, 44(3)(in Chinese)     

Synthesis and structural identification of a highly ordered mesoporous organosilica with large cagelike pores

Using 1,2-bis(trimethoxysilyl)ethane as organosiloxane precursor and a triblock copolymer surfactant, Pluronic F127, as template, a highly ordered mesoporous organosilica with large cagelike pores has been successfully synthesized. Its structure was resolved to be 3-D cubic Fmm by high-resolution transmission electron microscopy. The intergrowth of hexagonal close-packed and cubic close-packed phases was observed in this material. The effect of different siliceous precursors on the mesostructure was also investigated.     

Co-C bond dissociation energy and reaction volume change of 2',5'-dideoxyadenosylcobalamin studied by laser-induced time-resolved photoacoustic calorimetry

Time resolved photoacoustic calorimetry (PAC) was applied to a study of the photolysis of a coenzyme B(12) analog 2',5'-dideoxyadenosylcobalamin, which lacks an -OH group at the 2' position of ribofuranose ring. In aqueous solution, we report for the first time the quantum yield Phi(d) (0.25+/-0.02), Co-C bond dissociation energy (BDE; 31.8+/-2.5 kcal mol(-1)) and reaction volume change deltaV(R) (6.5+/-0.5 ml mol(-1)) due to conformation changes of the corrin ring and its side chains accompanying the cleavage of the Co-C bond. These values for the analog are very similar to those for the natural cofactor. Based our results and previous studies, a possible explanation for the similarity in their structure and properties versus the large difference in their enzymatic activity is discussed.     

An Investigation on the Production of Random Copolymer with Monothiocarbonate and Trithiocarbonate Units over Cyclic Thiocarbonate via Metal‐free Catalysis

Synthesis of poly(thiocarbonate)s from the copolymerization of epoxides and carbon disulfide (CS₂) remains a tough challenge, due to inevitable oxygen‐sulfur atom scrambling process. In this work, we utilized the oxygen‐sulfur exchange reaction (O‐S ER) to synthesize a random copolymer with monothiocarbonate and trithiocarbonate units from CS₂ and phenyl glycidyl ether (PGE) via metal‐free Lewis pairs. The copolymers contained monothiocarbonate and trithiocarbonate units of which the molar fraction could be tuned by varying either the types of Lewis pairs or the reaction temperature. Keeping track on the intermediate provided an insight in the process of O‐S ER and thus gave a hint to control the product structure. Production and consumption of phenyl thioglycidyl ether was the key process to regulate the chain structure. Remarkably, the oxygen atoms of PGE could be excluded out of the chain, resulting in the nearly complete production of poly(trithiocarbonate)s. Correspondingly, the refractive index of this kind of copolymer could be regulated in a wide range of 1.73—1.79 (at 590 nm).     

Synthesis of a Novel Type of Phosphates of Puerarin

A novel type of phosphated puerarin derivatives were synthesized through a simplified Atheron‐Todd reaction for the first time. The structure of these compounds were elucidated by IR, ESI‐MS and NMR. Moreover, the reason the dialkylphophite reagent had different chemselectivities toward different hydroxys on the puerarin was discussed.     

改进的微波辅助无溶剂法提取薄荷和陈皮中的挥发油组分

An improved solvent free microwave extraction, in which a kind of microwave absorption medium （carbonyl iron powder） was used, was applied to the extraction of essential oil from dried menthol mint and orange peel without addition of any solvent and pretreatment. It took much less time of extraction （30 min） than microwave-assisted hydrodistillation （90 min） and conventional hydrodistillation （180 min）. The kinds of chemical compositions in essential oil extracted by different methods were almost the same and such improved solvent free microwave extraction can be a feasible way in extraction of essential oil from dried plant materials.     

A New Anthraquinone from Clinopodium polycephalum Glyceroyl-1,6,8-trihydroxy-3-methyl-9,10-dioxo-2-anthracene Carboxylate

ClnOPodiumpoIycePhalum(VantjCYWhetHsuancalled'DuanXielin'inChineseisusedinfolkmedicineforthetreatInentofhaemorrhagiadisease.lInordertofmdtheactivecomPounds,studiesonthechedricalconstituentsofthewholeplan,collectedatHuoShanofAnhuiprovince,werecarriedout.Fromthealcoholicextracts,wehaveisolatedanewanthraquinone,Glyceroyl-l,6,8-trihydroxy-3-methyl-9)lO-dioxo-2-anthrcenecarboxylateI(Figurel).Iwasobtainedasredneedles,mP:ll9-l2l"C.TheHR-MSdareaffordedthefor-mulaasCl9Hl6O9(Found388.O791;…