羟丙基-β-环糊精毛细管胶束电动色谱法测定密蒙花中的芹菜素和木犀草素

通过优化缓冲溶液pH和浓度、SDS浓度和β-CD等条件,建立了一种HP-β-CD毛细管胶束电动色谱法测定密蒙花中的芹菜素和木犀草素的方法。在优化的条件下,2种物质在15min内得到良好分离。木犀草素和芹菜素的峰高和浓度在0．01—0．60g/L范围内成良好线性。2种物质基于迁移时间和峰高的相对标准偏差分别为1．2％、1．9％和2．5％、2．8％。检出限分别为0．005和0．0045g／L。     

苦瓜素的分离纯化与抗肿瘤活性的研究

本文报道了α－苦瓜素和β苦瓜素分离纯化的工艺改进,测定了两种苦瓜素的理化性质。实验证明,两种苦瓜素对小鼠Ｓ－１８０实体瘤均具有显著的抑制作用,抑瘤率分别为７１．２％和６８．６％;两种苦瓜素对人胃癌ＮＫＭ细胞株的ＤＮＡ,ＲＮＡ和蛋白质的合成亦均具有明显的抑制作用。     

高效液相色谱法检测弹性蛋白中锁链素

用高效液相色谱技术对弹性蛋白水解液中锁链素进行了测定。单一锁链素,锁链素、酪氨酸、苯丙氨酸混合液及弹性蛋白水解液经Ｃ１８柱分离,甲醇－水（２８,Ｖ／Ｖ）洗脱,紫外检测器２８０ｎｍ检测。锁链素与酪氨酸峰面积比（ＣＡ）和峰高比（ＣＨ）分别为１．４％和３．４％,标准曲线浓度范围０．１６～０．６４ｍｇ／Ｌ时相关系数为０．９９５６。结果表明：上述色谱条件可定量测定弹性蛋白中锁链素含量,无需将锁链素与水解液中其它氨基酸加以分离,而仅需同其它２７５ｎｍ有吸收的组分区分。     

高效液相色谱法测定灯盏花制剂中灯盏乙素含量

建立了高效液相色谱法(HPLC)测定灯盏花制剂中灯盏乙素含量的方法,运用二极管阵列检测器(PDA)进行光谱分析确认灯盏乙素,采用C18反相柱,以乙腈：水：醋酸(HAC)：2％磷酸(H3PO4)=20．0：77．5：2．0：0．5(V/V)为流动相测定了同一批灯盏花素片剂中灯盏乙素,含量为12．53％,标准偏差0．63,变异系数5．03％,回收率为100．17％．方法快速,精密度及准确度在允许范围内．     

反相高效液相色谱法测定雷公藤提取物中雷公藤甲素含量

应用反相高效液相色谱法检测了雷公藤提取物中雷公藤甲素的含量。样品经洗脱提取后,以Ｃ１８化学键合硅胶为固定相,乙腈－水（４０∶６０,Ｖ／Ｖ）为流动相,用２１０ｎｍ波长定量检测。测定结果表明,雷公藤甲素浓度在０．２５～４．００ｍｇ／Ｌ范围内线性良好,最低进样检测浓度为０．１ｍｇ／Ｌ。批内（ｎ＝５）及批间（ｎ＝５）测定相对标准偏差分别为１．９％～６．５％和２．７％～７．８％,回收率为８９．８％～９２．０％。     

高效毛细管电泳测定虎耳草属植物中虎耳草素含量

以苯乙胺为内标，建立了高效毛细管电泳法(HPCE)测定虎耳草属植物中虎耳草素含量的方法．讨论了缓冲溶液体系、pH值及缓冲液浓度对分离的影响．结果表明，以10mmol／L硼砂-盐酸缓冲液(pH9．00)为分离介质，虎耳草素标准品与内标实现基线分离，且实验结果线性关系良好(r=0．9989)，日内和日间相对标准偏差分别为1．7％和4．6％．     

高效液相色谱法分离和测定白菜黑斑病菌中的腐败菌素B

建立了一种高效液相色谱分离和测定白菜黑斑病菌腐败菌素B的新方法。被真菌毒素感染的白菜病叶用乙酸乙酯萃取，用Nove-Pak C18柱进行分离，流动相为乙腈－水（1＋1），pH3.42，流速1．0mL/min，紫外检测波长206nm，腐败菌素B的分离时间是11．49min，检出限达到2．3ng，线性动态范围至少是3个数量级。本方法应用于白菜黑斑病叶样品的测定，并进行了回收率试验，腐败菌素B的5次测定值RSD≤1．2％，平均回收率≥97．1％。     

原子吸收光谱法测定三醋酸纤维素膜中铜铁

运用空气-乙炔火焰原子吸收光谱法同时测定银锌电池三醋酸纤维素膜中铜铁含量，并对测定条件和干扰因素进行了综合分析．该测定方法具有很好的灵敏度，干扰少，选择性和重现性好等优点．测定样品铜铁含量的相对标准偏差均小于1．0％．标准加入回收率均在97．3％-98．8％范围内．完全适用于银锌电池三醋酸纤维素膜中铜铁含量的控制和样品系统分析．     

测定自来水中双氯芬酸的两种免疫分析方法对比研究北大核心CSCD

将双氯芬酸（Diclofenac,DCF）与牛血清白蛋白（BsA）通过活化酯法偶联制备人工免疫原,并免疫新西兰大白兔制得抗双氯芬酸的多克隆抗体。使用该抗体建立了测定环境水样中的双氯芬酸的间接竞争酶联免疫吸附分析（ic—ELISA）法;用生物素一亲和素（Biotin-Avidin,BA）标记抗体,建立测定双氯芬酸的BA—ELISA方法。ic-ELISA、BA-ELISA两种方法的线性范围分别为10～10。ng／L和1～10。ng／L;检测限分别为27．0ng／L与2．6ng／L;用于环境水样中双氯芬酸的测定,回收率分别为96．3％～106．7％与93．5％～118．4％。     

高效液相色谱法测定山生柳中酚苷类成分的含量

用高效液相色谱法测定山生柳中水杨苷、水杨酰水杨苷和木犀草素07－O－葡萄糖苷的含量，流动相为1．5％醋酸溶液－甲醇，Symmetry C18柱，柱温30℃，流速1．1mL/min，检测波长270nm，线性浓度范围分别为527．0－105．4um/mL,140-28.0ug/mL,81.0-16.2ug/mL，平均回收率是104．9％和103．6％，RSD分别为2．0％，0．3％和0．3％。     

石墨炉原子吸收法直接测定全血中镉和铅

直接测定人体血镉和血铅较为困难。本文介绍用铂作基体改进剂以提高镉、铅的灰化温度,在灰化阶段除去产生高背景吸收的蛋白,而不发生镉、铅的挥发损失。实现了不需消化样品、络合提取等复杂的化学前处理,用石墨炉原子吸收法和校正曲线直接测定。同时应用衬钽技术,大大延长了石墨管的使用寿命。     

Individual and simultaneous enzymatic determination of ethanol and acetaldehyde in wines by flow injection analysis

The individual and simultaneous enzymatic determination of ethanol and acetaldehyde in wine by flow injection analysis is described. Individual determinations of 0.002–0.016% (v/v) ethanol or 1.0–8.0 μg ml^?1 acetaldehyde with r.s.d. 0.7% and 0.5%, respectively, are done with a single-beam spectrophotometer, based on the use of alcohol dehydrogenase and aldehyde dehydrogenase. A diode-array detector and dual reagent injections are used for the simultaneous determination of the two compounds. The errors are 〈 3.5% and 〈 2.0% for ethanol and acetaldehyde, respectively, when the method is applied to wine samples.     

Microwave and ultrasonic extraction of chlorophenoxy acids from soil and their determination by fluorescence polarization immunoassay

Procedures were developed for the ultrasonic and microwave extraction of pesticides, 2,4-dichlorophenoxyacetic (2,4-D) and 2,4,5-trichlophenoxyacetic (2,4,5-T) acids from soils for the subsequent determination by fluorescence polarization immunoassay (FPIA). The effect of the matrix composition of soils on the FPIA results was studied, and the optimum extractants and extraction conditions were selected. It was found that 40% ethanol is optimum for both extraction and FPIA determination, because it does not cause antibody denaturation. The recovery of pesticides in soil was 80–132% for 2,4-D and 101–138% for 2,4,5-T. Microwave extraction is more efficient than ultrasonic extraction for the determination of 2,4-D and 2,4,5-T in soil. The detection limit in soil and the analytical range are 2 and 4–200 μg/g, respectively, for 2,4-D and 20 and 80–5000 μg/g, respectively, for 2,4,5-T. Results of the determination of 2,4-D in soil by FPIA are in good agreement with the results of the determination by high-performance liquid chromatography. The procedures can be used for the rapid determination of chlorophenoxy acids in soils.     

Individual and simultaneous determination of uric acid and ascorbic acid by flow injection analysis

Flow injection methods for the individual and simultaneous determination of ascorbic acid and uric acid are proposed. A spectrophotometer and a miniamperometric detector are connected in sequence. The calibration graphs for uric acid obtained by measuring its absorbance at 293 nm and its current at +0.6 V are linear up to at least 80 and 70 mug/ml, respectively, with an rsd (n = 10) of 1 % for both methods at mid-range concentrations. The calibration graph for ascorbic acid with amperometric detection is linear up to 80 mg/l. with an rsd (n = 10) of 0.8% at 30 mg/l. The simultaneous determination of uric acid and ascorbic acid is based on measurement of the absorbance of uric acid at 393 nm and amperometric determination of both analytes at +0.6 V. The average relative errors of the analysis of binary mixtures of uric acid and ascorbic acid are 2.2 and 4.2%, respectively.     

Determination of metrifonate and dichlorvos in whole blood using gas chromatography and gas chromatography-mass spectrometry

Analytical methods for determining metrifonate and dichlorvos in whole blood and a sampling procedure suitable for pharmacokinetic studies in man are described. Metrifonate concentrations were determined after chloroform extraction using gas chromatography-nitrogen-phosphorus detection. The within-assay coefficients of variation were 4 and 9% at 19.4 and 0.8 mumol/l (limits of determination), respectively. Dichlorvos was determined using gas chromatography-mass spectrometry of toluene extracts. The within-assay coefficients of variation were 2 and 5% at 225 and 50 nmol/l (limits of determination), respectively. Since both substances are chemically unstable, the blood was collected by dripping it directly from the vein into 0.74 M phosphoric acid.     

离子排斥色谱法同时测定葡萄糖醛酸和内酯及葡萄糖醛酸稳定性

建立了同时检测葡萄糖醛酸和葡萄糖醛酸内酯的离子排斥色谱法。 采用Boston HC-B75 H+色谱柱进行分离,以5 mmol/L H2SO4水溶液为流动相,流速0.6 mL/min,柱温25 ℃,紫外检测波长220 nm;根据外标法定量,葡萄糖醛酸和内酯分别在10～1200 mg/L和5～600 mg/L范围内线性良好（r＞0.9999）;葡萄糖醛酸、葡萄糖醛酸内酯的最低检测限及定量限均分别为0.1和0.3 mg/L,精密度实验RSD分别为1.00%和0.35%,平均回收率分别为99.69%和98.21%。 该检测方法简便、快速、灵敏,可用于葡萄糖醛酸和葡萄糖醛酸内酯的同时测定。 温度、pH值和溶剂对葡萄糖醛酸稳定性有影响,可为葡萄糖醛酸的分析与制备研究提供参考依据。     

离子交换分离富集和ICP-AES测定钨酸钠中微量钙和镁

本文首次提出了用ICP-AES法测定用D001-CC强酸型阳离子交换树脂预分离富集钨酸钠中Ca和Mg。Ca及Mg的平均口收率分别为95%及90%,相对偏差分别为1.8%及0.9%。     

Application of rhodanine,fluorene and semicarbazide hydrochloride as new spectrophotometric reagents for quinones

New selective and sensitive Spectrophotometric methods for quinone determination are described. Quinone samples are treated with either methanolic solution of rhodanine, fluorene in ammoniacal media or aqueous semicarbazide hydrochloride solution. Semicarbazide is the most sensitive reagent for the determination of 1,4-benzoquinone, 1,4-naphthoquinone and 2-methyl-1,4-naphthoquinone. Quinones substituted with electron withdrawing groups are better determined using rhodanine. The average recovery is 99.1%, 98.7% and 99.2% using rhodanine, fluorene and semicarbazide as reagents, respectively.