巴洛沙星-Tb3+-ATP荧光体系的建立及其分析应用

在二元配合物巴洛沙星-Tb3+中加入ATP,Tb3+在其特征波长545 nm处的荧光强度增强,据此建立了新的巴洛沙星-Tb3+-ATP荧光体系.在最优化实验条件下,增强的荧光强度与ATP的浓度呈良好的线性关系,线性范围为2.0×10-6～3.0×10-5 mol/L,检出限为8.0×10-7 mol/L.详细的机理研究表明,ATP能与巴洛沙星-Tb3+形成大的三元络合物荧光体系.新建立的荧光体系成功地应用于ATP注射液中ATP的定量检测.对不同批次ATP注射液进行加标回收试验,回收率为101％～106％,测定结果的相对标准偏差为1.1％～1.9％(n=5).     

铽-依诺沙星络合物与辅酶Ⅱ(NADP)的相互作用研究及其分析应用

实验发现,在pH=7.80最佳酸度下,辅酶Ⅱ(NADP)能使依诺沙星-Tb3 位于545 nm处的特征荧光强度显著增强。根据这一性质,以依诺沙星-Tb3 作为荧光探针,建立了一种利用荧光光谱测量NADP的新方法,线性范围为6.66×10-7~3.33×10-5mol.L-1,检出限为5.60×10-8mol.L-1。该法灵敏度高,选择性好,干扰少,操作简单,用于合成样中NADP的测定,结果满意。     

聚丙烯酸/萘酰亚胺纳米粒荧光增强法测定蛋白质

制备了水溶性的聚丙烯酸/萘酰亚胺荧光纳米粒,并利用牛血清白蛋白(BSA)对其荧光的显著增强效应,建立了测定蛋白质的新方法。在pH=3.0磷酸盐缓冲溶液及室温条件下,该纳米粒与BSA的作用5 min内即完成。以444nm为激发波长,在535nm处测定纳米粒/BSA体系的荧光,其荧光强度增加与0.15~7.5μmol·L-1浓度范围内的BSA呈线性关系,检测限为0.095μmol·L-1。该方法简单、快速、灵敏且重现性好,用于BSA合成样品及牛奶样品中蛋白质的测定,回收率范围为96.7%~102.6%,相对标准偏差(RSD)在3.91%以内。     

基于邻氟苯基荧光酮荧光探针的荧光光谱法测定牛血清白蛋白

在pH 7.40的磷酸盐缓冲溶液中,牛血清白蛋白(BSA)可使邻氟苯基荧光酮(o-FPF)荧光猝灭,β-环糊精的加入可使荧光猝灭强度(ΔF)增强,据此建立了一种基于o-FPF为荧光探针测定BSA的荧光光谱法。在选定的试验条件下,BSA浓度在6.0×10~(-9)~4.0×10~(-7)mol·L~(-1)范围内与ΔF呈线性关系,方法检出限(3s/k)为7.1×10~(-10)mol·L~(-1)。该方法用于测定牛奶、牛奶粉中的蛋白质含量,结果与考马斯亮蓝法测定结果相吻合,测定值的相对标准偏差(n=5)小于4%。通过测定荧光寿命、探讨温度对猝灭常数的影响以及紫外吸收光谱的变化,确定BSA与o-FPF之间的猝灭过程为静态猝灭。     

以1-酮-2-(对二甲氨基苯亚甲基)-四氢萘与β-环糊精的包合物为荧光探针测定牛血清白蛋白

基于一种分子内电荷转移(ICT)化合物,1-酮-2-(对二甲氨基苯亚甲基)-四氢萘(KDTN)与β环糊精(β-CD)所生成的包合物和牛血清白蛋白(BSA)形成三元超分子体系产生的荧光,且其荧光强度与BSA的质量浓度在3.31~662mg·L-1范围内呈线性关系,检出限(3S/N)为1.6mg·L-1,提出了以KDTN与β-CD包合物为新的荧光探针的荧光光谱法测定BSA含量。该反应体系的荧光发射峰位于540nm,测定在pH 9.18的B-R缓冲介质中进行。用标准加入法进行回收试验,测得平均回收率为99.4%,测定值的相对标准偏差(n=11)为2.2%。     

AlF_6~(3-)与BSA相互作用的光谱特性及分析应用

研究了AlF_6~(3-)与牛血清白蛋白(BSA)之间相互作用的光谱特性,考察了各种影响因素和适宜的反应条件,确定了体系的荧光光谱强度与牛血清白蛋白浓度之间的关系,建立了测定蛋白质含量的新方法。研究结果表明,在pH 4.0的三羟甲基氨基甲烷-HCl(Tris-HCl)缓冲介质中,以280 nm光激发,在静电引力和疏水力的作用下,AlF_6~(3-)与BSA之间形成的离子缔合物在330 nm处产生1个较强的荧光峰。当BSA的质量浓度在0.10~30.0μg/m L范围内时,体系的荧光强度变化值ΔF与牛血清白蛋白浓度之间有良好的线性关系,其检出限为5.11 ng/m L。方法可直接用于测定人血清中蛋白质的含量,回收率为103.1%~116.5%。     

荧光探针用于定量BSA测定的研究

设计合成了具有长发射波长(655 nm)的荧光探针WZK-31,建立了一种荧光增强分析测定牛血清白蛋白(BSA)的新方法。在模拟人体生理条件下,BSA的加入使探针荧光强度发生不同程度的增强。增强程度与0~53.20μg/m L范围的BSA的质量浓度呈线性关系。方法检出限为0.70μg/m L,干扰小。方法用于样品的测定,加标回收率为89.1%~90.8%。     

诺氟沙星荷移络合物的荧光特性和应用

研究了电子受体四氯对苯醌(TCBQ)和2,3二氰5,6二氯1,4对苯醌(DDQ)与电子给体诺氟沙星之间的荷移反应。实验发现,诺氟沙星与以上两种电子受体可生成稳定的nπ络合物,其荧光强度较之诺氟沙星分别增强了12和17倍。据此建立了两种基于荷移反应简便可靠地测定诺氟沙星的荧光光谱新方法。TCBQ法和DDQ法测定诺氟沙星的浓度分别为0.02~1.2和0.14~2.8mg/L时,荧光强度与质量浓度呈良好的线性关系。该方法已成功地用于药物制剂中诺氟沙星含量的测定,其回收率(%)分别为98.87±142~99.63±1.26和98.49±1.46~99.21±1.62。本方法也可用于生物体液中诺氟沙星的测定。     

培氟沙星-铽(Ⅲ)-牛血清白蛋白体系的荧光光谱及其应用

在pH 8.2的Tris-HCl缓冲溶液中, Tb3+与培氟沙星(PEFX)形成的配合物受290 nm紫外光激发发出Tb3+的特征荧光峰, 加入牛血清白蛋白(BSA)能大大增强体系的荧光强度, 由此建立了PEFX-Tb3+ 配合物探针测定BSA的方法. 与PEFX-Tb3+二元配合物相比, PEFX-Tb3+-BSA三元体系荧光强度显著增强. 研究了反应的最佳条件, 并对PEFX-Tb3+-BSA荧光增强作用的机理进行了探讨.     

诺氟沙星荧光光度法测定微量Al(Ⅲ)

铝对荧光试剂诺氟沙星有强的荧光增强作用,据此建立了测定微量铝的荧光分析方法。选择最大激发与发射波长分别为278 nm和441 nm,在pH 4.10的HAc-NaAc介质中,诺氟沙星的荧光强度变化与Al(Ⅲ)浓度呈良好的线性关系,线性范围为7.00×10-6~1.00×10-3mol/L,检出限为2.00×10-8mol/L,常见的共存离子不干扰测定。本方法已用于实际样品中Al(Ⅲ)的测定。     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Acid hydrolysis of carboxymethylcellulose of low degree of substitution

Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

Estimation of Kinetic Parameters of Thermal Oxidation of Ilmenite

The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe₂O₃. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mechanism of action of base-catalyzed oxygenation of phenol derivatives

Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。