高效液相色谱法测定生物样品中多种蝶呤类化合物

建立了一种同时分离测定人体尿液中4种蝶呤类化合物(新蝶呤、异黄蝶呤、蝶呤和生物蝶呤)的高效液相色谱法。采用SHIMADZU Shim-pack:Vp-ODS(250 mm×4.6 mm×5μm)色谱柱结合荧光检测器,在流动相为甲醇-水(10+90),流速1.0mL/min,荧光检测波长Ex390 nm,Em450 nm,柱温为室温的色谱条件下,4种蝶呤类化合物分离效果良好。尿液经0.45μm的一次性滤膜过滤,取10μL滤液直接进样测定。结果表明,各组分的线性范围为:新蝶呤0.05～1.20μg/mL,异黄蝶呤0.05～0.80μg/mL,蝶呤0.05～1.00μg/mL,生物蝶呤0.05～1.00μg/mL。4种组分的检测限均为0.01μg/mL。该方法可应用于临床癌症病人和健康人尿样中4种蝶呤类化合物的检测。     

纸色谱分离-荧光检测法测定人体尿液中的黄蝶呤

报道用丙醇-氨水(25％)-水(15：9：6．V／V)作展开剂,纸色谱分离人体尿液中的蝶呤类化合物,并利用黄蝶呤与其它蝶呤类化合物的荧光性质的差异来测定人体尿液中黄蝶呤的含量。黄蝶呤在0～0．6μg／10mL的范围内,其荧光强度与其荧光斑点的洗脱量呈良好的线性关系,从而建立了一种新的测定黄蝶呤的方法。该方法应用于人体尿液中黄蝶呤的测定,结果满意。     

薄层色谱-荧光检测法测定尿样中的黄蝶呤

系统研究了在展开剂V(正丙醇)∶V(浓氨水)=2∶3中利用薄层层析将尿液中的黄蝶呤和其它蝶呤类化合物分离,然后利用薄层荧光扫描法测定黄蝶呤。黄蝶呤在0.01～0.08μg范围内,其荧光斑点的积分面积与黄蝶呤的检测量呈良好的线性关系,从而建立了黄蝶呤的新的检测方法。方法可应用于尿样中的黄蝶呤测定。     

高效液相色谱-荧光检测法测定人体尿液中的蝶呤-6-羧酸

利用蝶呤-6-羧酸具有天然荧光的特点,建立了人体尿液中蝶呤-6-羧酸的高效液相色谱-荧光分析方法。尿液经硫酸铵处理后,过0.45μm水相滤膜,直接进行液相色谱分析,色谱柱为NOVA-PAK C18柱,保护柱为RCSS Guard-PAKTMC18柱,流动相为V(5 mmol/L KH2P04-NaOH缓冲溶液,pH 7.3)∶V(甲醇)=99∶1),流速为0.6 mL/min,荧光激发波长为338 nm,荧光发射波长为420nm。蝶呤-6-羧酸在0.05~1.2μg/mL范围内呈线性关系,相关系数为0.9974,检出限为0.010μg/mL。分别添加0.625、2.50和4.50μg蝶呤-6-羧酸标准品,平均回收率(n=5)在99.7%~105%之间,相对标准偏差小于3.6%。此法可用于临床尿样中蝶呤-6-羧酸的分析。     

同步荧光法测定人尿中异黄蝶呤

研究了一种测定人尿中异黄蝶呤的同步荧光分析方法.在KH2PO4-NaOH缓冲溶液中(pH 7.8),波长差(Δλ)为65 nm的条件下进行同步荧光扫描,可有效排除尿液中其它物质对异黄蝶呤测定的干扰.异黄蝶呤的质量浓度在0～1.4 μg/mL范围内与荧光强度呈良好的线性关系.线性方程为Ⅰ=4105.3ρ 59.696, 相关系数r=0.9997.异黄蝶呤添加到健康人和胃癌病人尿样中的平均回收率分别在102.9%～108.4%及85.6%～95.6%之间,其相对标准偏差(RSD)分别为0.37%～1.2%及1.0%～2.2%.方法已应用于人尿中异黄蝶呤的测定.     

高效液相色谱-荧光分析法同时测定人体尿液中黄蝶呤与异黄蝶呤

建立了高效液相色谱-荧光法同时测定癌症病人尿液中黄蝶呤及异黄蝶呤的新方法。选择荧光检测波长λex=345nm,λem=420nm。以磷酸盐缓冲溶液(pH=7.5)-甲醇(体积比为98∶2)为流动相,流速1.0mL/min,黄蝶呤与异黄蝶呤含量分别在0.0013～0.945μg/mL及0.00017～0.118μg/mL范围内与色谱峰面积呈良好的线性关系,线性相关系数分别为0.9999和0.9996,检出限分别为0.5ng/mL和0.05ng/mL,加标平均回收率在86.2%～107.5%之间。方法应用于癌症病人尿样分析,取得了较好的结果。     

二甲基黄褪色光度法测定微量溴酸根离子的研究

研究了二甲基黄与 Br O- 3的褪色反应 ,确定了最佳反应条件 ,建立了一种光度测定微量溴酸根离子的新方法。结果表明 :方法的表观摩尔吸光系数ε′=3.2× 1 0 4L· mol- 1· cm- 1,检出限为 4.2 9× 1 0 - 8g/m L ,线性范围为 0～ 1 2μg/1 0 m L。用于化学试剂中溴酸根离子的测定 ,结果满意     

曲安奈德的荧光光谱法研究

提出了测定曲安奈德 (TA)的简单、灵敏的荧光光谱新方法。实验条件包括浓硫酸、加热温度及时间、溶剂、β CD的用量及CTMAB的影响 ,建立了两种荧光光谱法测定TA的新体系 :(1)CTMAB体系 ,线性范围为 0～ 4 .6× 10 -6mol/L ,检出限为 3.5 9× 10 -8mol/L ;(2 ) β CD与乙醇体系 ,线性范围为 0～ 2 .3× 10 -6mol/L ,检出限为 1.9× 10 -8mol/L。用于实际药物试样分析 ,获得满意结果。     

反相流动注射化学发光法测定单宁

在碱性介质中 ,单宁对高碘酸钾氧化鲁米诺的化学发光反应有较强的增敏作用 ,据此建立了反相流动注射化学发光测定单宁的新方法 ,并研究了最佳反应条件。该方法快速、准确、线性范围宽 ,测定单宁的检出限为 1 .1 2× 1 0 - 9g/ m L,方法的线性范围为 2 .0× 1 0 - 8～ 6 .0× 1 0 - 6 g/ m L,对于 4.0× 1 0 - 6 g/ m L单宁 1 0次测定的相对标准偏差为 0 .79%。应用于中药五倍子、诃子中单宁的测定 ,结果满意     

铁-荧光镓极谱络合吸附波的研究

在 p H6.1 0的 0 .1 mol/L ( CH2 ) 6 N4-HCl底液中 ,用单扫示波极谱法可获得铁( ) -荧光镓体系灵敏的络合吸附波。在 1 .0× 1 0 - 7～ 7.0× 1 0 - 6 mol/L范围内 ,铁浓度与波高呈线性关系 ,检测限达 7.0× 1 0 - 8mol/L,已成功地应用于金属镁粉中的铁和铝的测定 ,并测得电活性络合物的组成为铁∶荧光镓 =1∶ 1 ,条件形成常数β=3 .2× 1 0 4,表面电极反应速率常数 ks为 2 .9s- 1 。     

Altered pterin patterns in photobehavioral mutants of Phycomyces blakesleeanus.

Pterins were extracted with methanol from sporangiophores of the lower fungus Phycomyces blakesleeanus and separated and identified by high performance liquid chromatography (HPLC) with fluorescence detection. The following pterins were found and identified for the wild-type strain NRRL1555: carboxypterin (6.7 x 10(-6) M), neopterin (4.2 x 10(-7) M), xanthopterin (5.3 x 10(-6) M), biopterin (3.9 x 10(-7) M), pterin (9.1 x 10(-7) M), and 6,7-dimethylpterin (1.2 x 10(-6) M). The HPLC elution profiles of the wild type were compared to a set of phototropism mutants (genotype mad) with specific defects in the light-transduction pathway. The mutant profiles were qualitatively similar to those of the wild type. Quantitative differences were, however, discerned for madA, madC, and madH mutants. The madA mutation was associated with increased amounts of biopterin and 6,7-dimethylpterin and a reduction of neopterin, pterin, xanthopterin, and unidentified pterins eluting at 14-18 min. The stimulatory effect of the madA mutation on biopterin and 6,7-dimethylpterin appears to be compensated by a secondary mutation (pde) which is responsible for the loss of 75% of adenosine 3',5'-cyclic monophosphate (cAMP)-phosphodiesterase activity. In a madA pde double mutant the amounts of biopterin and 6,7-dimethylpterin fell below the wild-type level. These results suggest that an increased level of endogenous cAMP represses the biosynthesis of these pterins. The madC mutation increased the amounts of biopterin and xanthopterin and that of the unidentified pterins which could be derivatized to carboxypterin. Single madB mutations had, compared to the wild type, two times higher amounts of biopterin and two times lower amounts of neopterin.(ABSTRACT TRUNCATED AT 250 WORDS)     

DETECTION OF PTERINS IN Phycomyces SPORANGIOPHORES*

Differential fluorometry with sodium dithionite showed pterin-like signals in extracts of Phycomyces sporangiophores. After iodine oxidation, pterin, biopterin and neopterin could be separated. The concentrations determined for these three pterins exceed the calculated minimal concentration of 3 times 10^?7M for the photoreceptor.     

REDUCED NEAR-UV SENSITIVITY IN Phycomyces MUTANTS AFFECTED IN THE BIOSYNTHESIS OF 6,7-DIMETHYL-8-RIBITYLLUMAZINE

Riboflavin-requiring mutants of Phycomyces blakesleeanus with defects in the genes ribA, ribB, ribC and ribD were analyzed with respect to their contents of flavins, 6,7-dimethyl-8-ribityllu-mazine (DMRL) and pterins as well as their phototropic sensitivity. Strains were grown on minimal medium enriched with 10^?6M riboflavin (RB), and the concentrations of the respective pigments in sporangiophores were determined by HPLC. In strains A607 ribC401 and A641 ribC402 madA7 a loss of DMRL correlated with a loss of near-UV sensitivity. In general terms, the results suggest the participation of DMRL in photoreception, which does not necessarily imply DMRL as a photoreceptor chromophore. In more specific terms, the result could be understood on the basis of a UV/blue-light photoreceptor, which includes besides a flavin also a lumazine-like chromophore. Mutants C318 ribA I and C323 ribA4 accumulated DMRL, the immediate precursor of RB, as well as biopterin and neopterin. Mutant C322 ribB contained normal amounts of DMRL and pterins. Mutant C324 ribD5 had reduced amounts of neopterin and biopterin. The fact that some of the RB-requiring mutants displayed abnormal amounts of pterins indicates a common regulation for the flavin and the pterin pathway.     

用单分子胶束荧光法测定蛇床子中的蛇床子素

根据胶束增溶增敏作用 ,以β-环糊精为胶束试剂 ,测定了蛇床子中蛇床子素的含量。蛇床子素的线性范围为 2× 1 0 -8～ 8× 1 0 -7g/m L,检出限为 1 .89× 1 0 -10 g/m L,平均回收率为 98%。     

毛细管电泳在线化学发光分离及检测铬（Ⅲ）与钒（Ⅴ）

基于在碱性介质中 Cr( )和 V( )对鲁米诺和过氧化氢的催化化学发光反应 ,研究了毛细管电泳在线化学发光分离和检测 Cr( )和 V( )。方法简便、快速、灵敏、进样量少。 Cr( )和 V( )的检出限分别为 7.8× 1 0 - 8mol/L和 5.0× 1 0 - 6mol/L ,线性范围分别是 32～ 80 ng/m L和 0 .55～ 3.0μg/m L     

Determination of total oncopterin,neopterin and biopterin in human urine by high performance liquid chromatography with solid phase extraction

A new, sensitive method for the determination of oncopterin, biopterin, and neopterin in human urine has been developed using SPE with 6,7‐dimethylpterin as internal standard and gradient HPLC with fluorescence detection. SPE was tested for the pre‐treatment of urine samples on different types of sorbents (strong ion exchange resins, polar adsorbents, and reversed‐phase sorbents). RP‐SPE with subsequent evaporation of eluate has been found to be the most appropriate. The extraction efficiency exceeded 95% for all selected pterins. The extracted pterins were subsequently analyzed on a Purospher RP‐18 RP column. The LOD of oncopterin was 1.43 nmol/L of urine. The intra‐day and inter‐day imprecision at a physiological oncopterin concentration never exceeded 10%. The potential of this method was tested using urine samples of healthy volunteers and cancer patients without methotrexate therapy.     

Simultaneous determination of lappaconitine hydrobromide and isopropiram fumarate in rabbit plasma by capillary electrophoresis with electrochemiluminescence detection

A CE electrochemiluminescence (CE-ECL) method for simultaneous determination of lappaconitine hydrobromide (LH) and isopropiram fumarate (IF) has been first established, with a chemically modified platinum electrode by europium (III)-doped Prussian blue analogue film as a working electrode. The conditions for CE separation and ECL detection are discussed and optimized in detail. It has been proved that 20 mmol/L phosphate buffer (pH 8.5) containing 5% (v/v) ACN and 0.17 mol/L SDS could achieve the most favorable resolution, and the high sensitivity of detection was obtained by maintaining the detection potential at 1.23 V. Under optimized conditions, a baseline separation for the two analytes was achieved within 6 min, and the standard curves were linear in the range of 1.0×10(-7) ～ 5.0 × 10(-5) g/mL for LH and 4.0 × 10(-8) ～ 1.0 × 10(-5) g/mL for IF with the detection limits (3σ) of 6.6 × 10(-8) g/mL for LH and 3.7 × 10(-8) g/mL for IF, respectively. The precisions of intra- and interday measurements for LH and IF were less than 4.21 and 2.61%, respectively. The applicability of the proposed method was illustrated in the determination of LH and IF in rabbit plasma with recoveries between 95.6 and 103.0%.     

钯(Ⅱ)-盐酸吗啉胍螯合物与卤代荧光素类染料相互作用的共振瑞利散射光谱及其分析应用

在pH值为4.2~4.4的HAc-NaAc介质中,盐酸吗啉胍(ABOB)与Pd(Ⅱ)反应形成螯合阳离子[Pd(ABOB)2]2+,它能进一步与曙红Y(EY)、赤藓红(Ery)和二溴荧光素(DBF)阴离子形成离子缔合物,此时将引起共振瑞利散射(RRS)的急剧增强并产生新的RRS光谱。 盐酸吗啉胍与Pd(Ⅱ)和3种染料反应后的产物具有相似的光谱特征,最大RRS波长位于315 nm附近。 在一定条件下散射增强(ΔI)与ABOB浓度成正比,EY、Ery和DBF这3个体系的线性范围分别为0.012×10-6~1.2×10-6 g/mL、0.23×10-6~2.3×10-6 g/mL和0.24×10-6~1.5×10-6 g/mL。 方法具有较高的灵敏度,对于ABOB的检出限依次为0.003 6×10-6、0.070×10-6和0.025×10-6 g/mL,其中以EY体系灵敏度最高,其次是DBF和Ery。 研究了适宜的反应条件和影响因素,表明本方法具有良好的选择性,并以EY体系为例考察了共存物质的影响。 据此建立以曙红Y作探针,用RRS技术快速、简便,高灵敏测定ABOB的新方法。 文中还对离子缔合物的形成和反应机理进行了讨论。     

介孔涂层固相微萃取-高效液相色谱法测定水样中邻苯二羧酸酯化合物

以苯基官能化MCM-41介孔复合体作为固相微萃取(SPME)的吸附涂层, 与高效液相色谱(HPLC)联用测定了不同水样中邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)和邻苯二甲酸二辛酯(DOP)的含量, 对SPME的吸附和解吸时间、温度、搅拌速度进行了优化, 线性范围分别为1.19×10-4～119 μg/L、 1.12×10-4～112 μg/L、 1.05×10-4～105 μg/L和9.80×10-5～98 μg/L, 检出限依次为0.030、 0.027、 0.029和0.022 ng/L. 使用该方法测定了多种水样中邻苯二羧酸酯类化合物.