Review on recent advances in the analysis of isolated organelles

The analysis of isolated organelles is one of the pillars of modern bioanalytical chemistry. This review describes recent developments on the isolation and characterization of isolated organelles both from living organisms and cell cultures. Salient reports on methods to release organelles focused on reproducibility and yield, membrane isolation, and integrated devices for organelle release. New developments on organelle fractionation after their isolation were on the topics of centrifugation, immunocapture, free flow electrophoresis, flow field-flow fractionation, fluorescence activated organelle sorting, laser capture microdissection, and dielectrophoresis. New concepts on characterization of isolated organelles included atomic force microscopy, optical tweezers combined with Raman spectroscopy, organelle sensors, flow cytometry, capillary electrophoresis, and microfluidic devices.     

Synthesis of cysteamine-coated CdTe quantum dots and its application in mercury (II) detection

High-quality cysteamine-coated CdTe quantum dots (CA-CdTe QDs) were successfully synthesized in aqueous phase by a facile one-pot method. Through hydroxylamine hydrochloride-promoted kinetic growth strategy, water-soluble CA-CdTe QDs could be obtained conveniently in a conical flask by a stepwise addition of raw materials. The photoluminescence quantum yield (PL QY) of the obtained QDs reached 9.2% at the emission peak of 520 nm. The optical property and the morphology of the QDs were characterized by UV–vis absorption spectra, photoluminescence spectra (PL) and transmission electron microscopy (TEM) respectively. Furthermore, the fluorescence of the resultant QDs was quenched by copper (II) (Cu²⁺) and mercury (II) (Hg²⁺) meanwhile. It is worthy of note that to separately detect Hg²⁺, cyanide ion could be used to eliminate the interference of Cu²⁺. Under the optimal conditions, the response was linearly proportional to the logarithm of Hg²⁺ concentration over the range of 0.08–3.33 μM with a limit of detection (LOD) of 0.07 μM.     

Photophysics of Schiff Bases: Theoretical Study of Salicylidene Methylamine

The proton‐transfer reaction in a model aromatic Schiff base, salicylidene methylamine (SMA), in the ground and in the lowest electronically‐excited singlet states, is theoretically analyzed with the aid of second‐order approximate coupled‐cluster model CC2, time‐dependent density functional theory (TD‐DFT) using the Becke, three‐parameter Lee–Yang–Parr (B3LYP) functional, and complete active space perturbation theory CASPT2 electronic structure methods. Computed vertical‐absorption spectra for the stable ground‐state isomers of SMA fully confirm the photochromism of SMA. The potential‐energy profiles of the ground and the lowest excited singlet state are calculated and four photophysically relevant isomeric forms of SMA; α, β, γ, and δ are discussed. The calculations indicate two S₁/S₀ conical intersections which provide non‐adiabatic gates for a radiationless decay to the ground state. The photophysical scheme which emerges from the theoretical study is related to recent experimental results obtained for SMA and its derivatives in the low‐temperature argon matrices (J. Grzegorzek, A. Filarowski, Z. Mielke, Phys. Chem. Chem. Phys. 2011 , 13, 16596–16605). Our results suggest that aromatic Schiff bases are potential candidates for optically driven molecular switches.     

新型荧光光纤免疫磁珠流动分析系统研究（Ⅰ）

将荧光免疫分析技术、光纤传感技术、流动注射技术和免疫磁珠分离技术联用,建立了一种新型荧光光纤免疫磁珠流动分析系统,并采用荧光素异硫氰酸酯（FITC）对系统性能进行考察,结果表明该分析系统设计合理,性能可靠,在临床、环保等领域有广泛的应用前景。     

荧光分子开关的研究进展

荧光分子开关是超分子化学领域的研究热点之一,本文根据开关动作完成的方式对近年来研究的各类荧光分子开关进行了简要的归类总结,并介绍了一些具有特殊功能的荧光分子开关器件.     

4,4′-[1,n-亚烷基双[(E)-2-(4-氧苯基)乙烯基]]双吡啶的光化学性质

通过E-[4-[2-(4-羟基苯基)乙烯基]吡啶与1,n-二溴烷烃亲核取代反应合成了4,4′-[1,n-亚烷基双[(E)-2-(4-氧苯基)乙烯基]]双吡啶[n=2(Ia),3(Ib),4(Ic),6(Id)].用元素分析、红外、紫外和质子核磁共振谱鉴定了Ia～Id的结构.将Ia～Id的稀溶液用中压汞灯和低压汞灯交替照射,发现其分子内光环加成反应的存在,并且随着亚烷基碳链的延长,反应速度加快.研究还发现锌离子可以与吡啶环上氮原子发生螯合作用使分子内光环加成反应加快.本文化合物荧光很弱,在较高浓度下有较强分子间激基缔合物荧光.     

β-环糊精与分散RGFL染料二元包络物研究

本文从 β-环糊精 (β- CD)与分散 RGFL染料包络反应的紫外 -可见光谱、二阶导数光谱和荧光光谱现象分析 ,得出 β- CD与 RGFL形成摩尔比为 1∶ 1包络物 ,包络物的平衡常数 Kf=1 .5× 1 0 3 L/mol。初步推测包络形成机制及包络物形式。     

基于表面富Cd2+的硫化镉量子点荧光增强测定半胱氨酸

采用一步法可控合成了表面富Cd2+的水溶性荧光硫化镉量子点,并成功用于半胱氨酸测定.通过控制镉-硫前驱体合适比例,使合成的量子点表面富含Cd2+,它们能与半胱氨酸分子中巯基结合引起体系量子点荧光增强,由此实现半胱氨酸的选择性定量分析检测.在pH=2.87的B-R缓冲体系中,测定半胱氨酸的线性区间分别为0.01～5.0 μmol/L和5.0～100 μmol/L;检出限(3σ)为3.3 nmol/L,且其它氨基酸干扰小,可应用于混合氨基酸合成样品、复方氨基酸注射液和人血清实际样品中半胱氨酸的检测.     

碱性橙与蛋白间的特异性与非特异性作用荧光光谱比较

将碱性橙与抗体的作用、碱性橙与牛血清白蛋白(BSA)间的作用分别作为特异性作用和非特异性作用模型,采用荧光光谱法固定激发波长为280 nm,扫描不同温度下碱性橙与抗体和牛血清白蛋白两种相互作用,在300～600 nm的发射波长,比较了两种相互作用的差异.结果表明,碱性橙与抗体结合为单一的静态猝灭过程,二者之间的作用力主要为静电作用力;在溶液中,二者以摩尔比1∶1结合,结合常数为3.88×104 L/mol(25.C),3.73×104 L/mol(37.C)和2.35×104 L/mol (45.C);碱性橙距抗体分子色氨酸残基最短距离(r)为5.52 nm.碱性橙与BSA的结合也为静态猝灭,作用力为静电作用力.但碱性橙与抗体作用过程中形成了激基复合物,与BSA则不形成激基复合物.