以不对称长链叔胺为中性载体的PVC膜PH电极的研究

合成了一系列不对称长链叔胺类化合物作中性载体，研制成ＰＶＣ膜ｐＨ电极。其中（２－羟基苄基）二正癸胺、（β－氰乙基）ＬＡ－２、（２－羟基苄基）ＬＡ－２的电极线性范围分别为ｐＨ２．５～１２．５、ｐＨ２．５～１２．５、ｐＨ３．０～１２．５，斜率分别为５６．６±０．４ｍＶ／ｐＨ、５６．３±０．７ｍＶ／ｐＨ、５５．９±０．３ｍＶ／ｐＨ（３０℃）。这些ｐＨ电极内阻低，响应速度快，性能较稳定，可用于血清样中的ｐＨ值测量。此外，以（２－羟基辛基）ＬＡ－２为载体可制成流通式ＰＶＣ膜ｐＨ内电极型氨气敏电极。     

卡尔曼滤波-分光光度法用于多组分分析

本文综述了卡尔曼滤波在多组分光度分析中的应用。通过理论分析与实验验证探讨了滤波过程的某些基本问题,如误差协方差矩阵计算的公式选择、滤波初始估计值对结果的影响、新息序列的相关性检验对结果可靠性的判别、信息量的度量与滤波过程是否达到最优及波长选择的某些关系、实验联机处理的某些问题等。     

A reusable piezo-immunosensor with amplified sensitivity for ceruloplasmin based on plasma-polymerized film

A reusable piezoelectric immunosensor with amplified sensitivity has been developed for the detection of ceruloplasmin (CP) in human serum. The quartz crystal microbalance (QCM) was deposited with plasma-polymerized n-butyl amine film with the surface topology further characterized by using atomic force microscopy (AFM). Anti-ceruloplasmin antibody (CP-Ab) was electrostatically adsorbed on the PPF-modified crystal via an oppositely charged polyelectrolyte layer of alginate. It was found that the alginate-mediated immobilization interface could allow for antibodies to be largely immobilized with well-retained immunoactivity. In particular, a simple regeneration process for the sensor produced, i.e. by shifting the pH, can also be realized. Moreover, an optimized assay medium containing polyethylene glycol (PEG) was tested with enhanced immunosensing response (sensitivity). A dynamic concentration range of two orders of magnitude and a detection limit of 0.15 μg ml⁻¹ of CP were observed. Analytical results of clinical samples show that the developed immunoassay is comparable with the enzyme-linked immunosorbent assay (ELISA) method. However, it presents some superior advantages over the traditional sandwich format in that the analyzing performances are direct, rapid and simple without multiple separation and labeling steps.     

Preparation of a novel fluorescence probe based on covalent immobilization by emulsion polymerization and its application to the determination of metronidazole

A novel method of preparing fluorescence particle probe by emulsion polymerization with covalent immobilization of indicator dye was described. A terminal double bond was attached to 3-amino-9-ethylcarbazole (AEC) via methacryloyl chloride, and the resultant compound was copolymerized with butyl methacrylate. The obtained polymer particles were used as a fluorescence probe, which is almost free of dye leaching, and has higher photostability and lower toxicity in comparison with free AEC. This probe holds great potential for the applications in intracellular measurements. In present study the prepared probe was used for the determination of metronidazole. The results revealed that the probe showed good selectivity and had a linear response to the analyte in the range from 2.0 × 10⁻⁵ to 1.0 × 10⁻³ mol l⁻¹ with a detection limit of 9.0 × 10⁻⁶ mol l⁻¹.     

Renewable urea sensor based on a self-assembled polyelectrolyte layer

A renewable urea sensor based on a carboxylic poly(vinyl chloride) (PVC-COOH) matrix pH-sensitive membrane has been proposed, in which a positively charged polyelectrolyte layer is first constructed by using a self-assembly technique on the surface of a PVC-COOH membrane, and urease, with negative charges, is then immobilized through electrostatic adsorption onto the PVC-COOH membrane, by controlling the pH of the urease solution below its isoelectric point. The response characteristics of the PVC-COOH pH-sensitive membrane and the effects of experimental conditions have been investigated in detail. Compared with conventional covalent immobilization, the urea sensor made with this self-assembly immobilization shows significant advantage in terms of sensitivity and ease of regeneration. The potential responses of the urea sensor with self-assembly immobilization increase with the urea concentration over the concentration range 10(-5) - 10(-1) mol l(-1), and the detection limit is 0.028 mmol(-1). Moreover, this type of urea sensor can be repeatedly regenerated by using a simple washing treatment with 0.01 mol l(-1) NaOH (containing 0.5 mol l(-1) NaCl) and 0.01 mol l(-1) HCl. The urease layers and the polyelectrolyte layers on the PVC-COOH membrane are removed, the potential response of the sensor to urea solutions of different concentrations returns nearly to zero, and another assembly cycle of urease and polyelectrolyte can then be carried out.     

白芷叶中分泌道显微和超微结构的研究

本文对白芷叶中分泌道的显微和超微结构进行了研究。白芷叶中分泌道是由一层上皮细胞围绕一圆形腔道而成,分布于叶片、叶鞘和叶柄的薄壁组织及较大叶脉或维管组织的次生韧皮部中,分泌道的发生方式为裂生型,其腔隙的扩大主要依靠上皮细胞本身的分裂生长以及周围细胞插入到上皮细胞之间。电镜观察结果表明分泌道原始细胞之间裂开形成腔隙可能与高尔基体分泌果胶酶进入到相邻细胞壁间而导致中层溶解有关,成熟分泌道上皮细胞中含有丰富的质体和内质网,其中大多数质体被内质网鞘所围绕,分泌道发育过程中上皮细胞超微结构最显著变化是质体、内质网和嗜锇滴数量的改变,它们随着分泌道的成熟而增加,随着分泌道的衰老而减少,嗜锇物质主要由质体、鞘内质网和细胞质内质网合成,而线粒体、液泡和细胞质也可参与分泌物的合成和运输过程     

伯胺化合物的化学衍生萤光法研究

用邻苯二甲醛和邻萘二甲醛对伯胺化合物包括有机胺和氨基酸进行化学衍生萤光测定,方法灵敏度高、操作简便,用于某些试样分析,结果良好。还研究了有关反应的动力学参数。     

刀豆组织电极用于脲测定的研究

关于生物组织传感器的研究,Arnold有详细综述。刀豆中包含丰富的脲酶,本文报道将刀豆切片与自制石墨内导PVC膜pH电极型氨气敏电极偶合制成了刀豆切片脲电极,对其响应特性、介质条件、固定化及切片厚度等因素进行了研究,取得了较满意的结果。     

漫谈分析化学教学改革与课程建设

1 关于分析化学的基础学科定位 分析化学界常用“分析科学”一词作为“分析化学”的同义语,这反映分析化学涉及广泛的多学科协同发展,但这并不改变分析化学是化学一级学科下的学科分支这一基本学科定位。分析化学的学科定位首先是由其研究对象所决定的。不论分析化学使用化学的、物理学的、生物学的或其他学科的原理与方法,其研究对象始终是物质的化学成分与结构,都是为了完成相关的化学定性、定量及结构分析。     

A label-free fluorescence DNA probe based on ligation reaction with quadruplex formation for highly sensitive and selective detection of nicotinamide adenine dinucleotide

A simple label-free fluorescent sensing scheme for sensitive and selective detection of nicotinamide adenine dinucleotide (NAD(+)) has been developed based on DNA ligation reaction with ligand-responsive quadruplex formation. This approach can detect 0.5 nM NAD(+) with high selectivity against other NAD(+) analogs.