傅里叶变换近红外光谱法测定大麦中蛋白质、淀粉和赖氨酸含量

采用傅里叶变换近红外光谱法测定大麦中蛋白质、淀粉、赖氨酸的含量，并用光谱影响值法(leverage)对异常值进行判断和处理。蛋白质、淀粉和赖氨酸含量近红外光谱分析模型的测定系数R。分别为0．985、0．973和0．978；检验集的化学值与模型预测值的相关系数r分别为0．9853、0．9644和0．9172，分析模型的预测相对标准偏差RSD分别为4．0％、2．4％和5．4％，该结果可替代经典分析方法，满足农产品快速分析的需要。     

原子荧光光谱法测定水中的痕量砷、硒、汞

建立了测定水中痕量砷、硒、汞三种元素的原子荧光光谱法。利用AFS-230型双道原子荧光光度计可双道分析的特点,采用氢化物发生原子荧光光谱法联合测定砷、硒,采用冷原子荧光光谱法单独测定汞。As、Se、Hg的线性相关系数分别为：0．9994、0．9995、0．9994,检出限分别为1．60、0．89、0．029μg／L,测定结果的相对标准偏差分别为3．8％、5．7％、4．6％,平均加标回收率分别为100．1％、101．4％、99．6％。     

ICP-AES法同时测定锰矿石中铁、铝、钛、钙、镁、磷、钡、铅的含量

锰矿石样品用HNO3-HF-HClO4酸溶除硅后,对采用ICP-AES法测定其中的铁、铝、钛、钙、镁、磷时,同时测定钡、铅的相关条件进行了试验。主要对酸溶样能否分解重晶石或天青石等含钡矿物进行了探讨,测定了3个国家级标准样品。测定结果与标准值吻合。用标准加入法测得的钡和铅的回收率分别为96．0％-100．5％,97．1％～100．0％。用该法对含钡量较高的澳大利亚锰矿进行分析,测定结果的相对标准偏差为0-82％,并将测定结果与X荧光光谱法测定结果进行了比对。     

抑制型离子色谱法测定白酒中的F-、Cl-、NO2-、H2 PO4-、NO3-

用抑制型离子色谱法测定白酒中的F^-、Cl^-、NO2^-、H2PO4^-、NO3^-。流动相为4mmol／LNa2CO3—3 mmol／LNaHCO3混合溶液,流速为1．5mL／min,进样量为0、5mL,在最佳色谱条件下,5种无机阴离子10min内实现基线分离。F^-、Cl^-、NO2^-、H2PO4^_、NO3^-的检出限分别为0、008、0．012、0、030、0．068、0．077mg／L。测定结果的相对标准偏差分别为1．86％、1．30％、2．06％、1．82％、1．50％,回收率分别为108．0％、94．0％、101．0％、98．7％、94．4％。     

氢化物-原子荧光光谱法连续测定锌精矿中砷、锑、铋、锡

用氢化物-原子荧光光谱法,一次性分解样品,在L-半胱氨酸存在下,实现了锌精矿中As、Sb、Bi、Sn的连续测定。其回收率分别为92．8％～105．0％、96．0％～109．3％、96．0％～111．6％和96．7％～103．7％;检出限分别为0．35、0．31、0．19和0．35μg／L。用该方法分析锌精矿样品,结果满意。     

溴酚蓝离子对萃取分光光度法测定长春花中总生物碱

以文多灵为对照品,溴酚蓝为显色剂,在pH3．0缓冲溶液条件下于30℃显色5min,用三氯甲烷萃取,于413nm波长处采用离子对萃取分光光度法测定长春花中总生物碱的含量。结果表明：文多灵在0．04～0．28g·L^-1浓度范围内与吸光度呈线性关系,回归方程为y=0．1824X－0．03,相关系数为0．9993,文多灵的平均回收率为99．49％,总生物碱样品在10～50min内测定稳定。经测定长春花的根、茎、叶、花、种子等不同部位中总生物碱含量分别为2．230％,0．411％,1．098％,0．503％和0．013％。     

ICP-AES法测定玻璃器皿中铅、镉、砷、锑溶出量的研究

采用ICP-AES法同时测定玻璃器皿中铅、镉、砷、锑的溶出量,对ICP-AES法测定4％乙酸浸泡液时分析线的选择和射频功率、载气压力的影响,以及基体和共存离子的干扰情况等进行了研究。4种元素的检出限分别为铅0．012mg／L,镉0．0009mg／L,砷0．015mg／L,锑O．015mg／L,加标回收率为97．3％～102．0％,测定结果的相对标准偏差为0．45％～1．36％（n=6）.     

ICP-AES法测定锡精矿中锡、铜、铅、铁的含量

建立了过氧化钠熔融分解样品、电感耦合等离子发射光谱法（ICP-AES）测定锡精矿中锡、铜、铅、铁的新方法。对试样分解方法、过氧化钠用量、元素分析谱线等进行了讨论。选择过氧化钠用量为2．0g,样品熔融温度为850~C,锡、铜、铅、铁分析谱线分别为189．991,324．754,220．353,259．940nm。将该方法应用于标准样品（BY0107—1）中Sn,Cu,Pb,Fe的测定,待测元素的回收率在92．0％-101．6％之间,检出限为分别为0．006,0．002,0．005,0．001μg／mL,测定结果的相对标准偏差为0．16％～2．11％（n=5）。     

微波消解-ICP—MS法同时测定砖茶中的铅、铜、铬和16种稀土元素

采用微波消解处理样品,以电感耦合等离子质谱（ICP-MS）法同时测定砖茶中的铅、铜、铬和16种稀土元素。采用外标法绘制校准曲线,分析了茶叶国家标准物质GBW 10016,测定值与标准值吻合。检出限为0．055-0．765μg／蚝,样品测定结果的相对标准偏差为0．2％～4．7％（n=6）。用加标回收的方法评价了该方法的准确性,回收率为88．0％-102．7％。该方法测定结果与电热板湿法消解前处理测定结果相比差异不显著。     

AlCl3显色分光光度法测定香椿叶中总黄酮

建立了AlCl3显色分光光度法测定香椿叶提取液中总黄酮的测定方法。研究表明：在弱酸性条件下，香椿叶提取液中总黄酮与AlCl3形成稳定的黄色配合物，在415nm处测定显色液的吸光度确定总黄酮的量。以芦丁为标样，黄酮量在2．41—30．1mg／L范围内，服从比耳定律，回归方程A=0．0318ρ＋0．0285，相关系数R^2=0．9994，方法的回收率为96．4％。103．4％，相对标准偏差（RSD）为0．84％。     

Simultaneous determination of vitexin-2"-O-glucoside, vitexin-2"-O-rhamnoside, rutin, and hyperoside in the extract of hawthorn (Crataegus pinnatifida Bge.) leaves by RP-HPLC with ultraviolet photodiode array detection

RP-HPLC with UV photodiode array detection (UV-DAD) was developed and validated for the simultaneous determination of vitexin-2"-O-glucoside, vitexin-2"-O-rhamnoside, rutin, and hyperoside in the extract of hawthorn (Crataegus pinnatifida Bge.) leaves. The analytes of interest were separated on a Diamonsil C18 column (250 x 4.6 mm id, 5 microm) with the mobile phase consisting of THF/ACN/methanol/ 0.05% phosphoric acid solution (pH 5.0) (18:1:1:80 v/vl/v). The flow rate was set at 1.0 mL/min and the eluent was detected at 340 nm for the four flavonoids. The method was linear over the studied range of 1.00-100 microg/mL for the four analytes of interest with the correlation coefficient for each analyte greater than 0.999. The LOD and LOQwere 0.03 and 0.10 microg/mL, 0.03 and 0.10 microg/mL, 0.05 and 0.15 pg/mL, 0.10 and 0.30 microg/mL for vitexin-2"-O-glucoside, vitexin-2"-0-rhamnoside, rutin, and hyperoside, respectively. The optimized method was successfully applied to the analysis of four important flavonoids in the extract of hawthorn leaves. The total amounts of the four flavonoids were 22.2, 62.3, 4.27, and 8.24 mg/g dry weight for vitexin-2"-O-glucoside, vitexin-2"-O-rhamnoside, rutin, and hyperoside in the extract of hawthorn leaves, respectively.     

High-performance liquid chromatographic determination of oligomeric procyanidins from dimers up to the hexamer in hawthorn

An HPLC method using UV diode array detection was developed for analysing procyanidins qualitatively and quantitatively up to the hexameric level in hawthorn samples. The analysed compounds included procyanidin dimers B-2, B-4 and B-5, procyanidin trimers C-1, epicatechin-(4beta-->8)-epicatechin-(4beta-->6)-epicatechin and epicatechin-(4beta-->6)-epicatechin-(4beta-->8)-epicatechin, a tetramer D-1 and a pentamer E-1 both consisting of (-)-epicatechin units linked through C-4beta/C-8 bonds. The concentrations of two unknown tetramers and a hexamer F were also quantified. The oligomeric procyanidins (OPs) were specifically determined due to the development of a method for isolating them from hawthorn during sample preparation. The pattern of oligomeric procyanidins in the leaves, flowers and fruits was similar, but the concentrations varied depending on the part of the plant. The concentration in leaves was 1.6%, in flowers 1.2% and in fruits 0.2% of the dry mass. The method was validated with respect to repeatability, recovery, linearity, and sensitivity. The repeatability for the quantitative analytical method of all the OPs in leaves was 7.7%, in flowers 8.8%, and in fruits 12.3%. The recovery of the main OPs ranged from 91 to 97%. The correlation coefficients of calibration curves were between 0.997 and 1.000. The limits of quantitation for different procyanidin standards were 0.05-0.12 mg/ml, when 10 microl of each standard solution was injected into the HPLC.     

山楂及其中药制剂中无机元素的光谱测定

采用灰化法对山楂、焦山楂、保和丸进行了处理,利用火焰原子吸收法测定了其中无机元素的含量,方法的回收率在95.7%～106.5%之间,相对标准偏差RSD在0.1%～2.6%之间,测定结果准确可靠.结果表明,山楂及其中药制剂中K、Ca、Mg、Fe含量较高.此测定结果可为探讨山楂中微量元素含量与药效的相关性提供科学数据.     

微乳液相色谱法同时测定山楂叶提取物中4种黄酮成分

建立了一种新的微乳体系,用于微乳液相色谱同时分析山楂叶提取物中牡荆素鼠李糖苷、芦丁、牡荆素及金丝桃苷4种黄酮成分.通过对影响分离选择性的主要因素进行考察,得到最佳微乳体系的组成为: 1.0%(w/w) 聚氧乙烯月桂醇(Brij35)-1.1%(w/w)正丁醇-0.1%(w/w)正辛醇-0.3%三乙胺(V/V)(H_3PO_4调节至pH 2.5).在此微乳体系中,表面活性剂类型和浓度、油相种类、添加剂三乙胺、流动相的pH值对4种黄酮成分的分离起到了重要的作用.选择Venusil ASB C_(18)色谱柱(150 mm×4.6 mm, 5μm),流速为0.8 mL/min,检测波长为360 nm,柱温为35 ℃.结果显示,4种黄酮成分在27 min内达到基线分离,在0.95～140.8 mg/L范围内,4个黄酮成分的线性相关系数r≥0.9995,平均回收率98.6%～101.6%.本方法可应用于山楂叶提取物中4种主要黄酮成分的质量分析.     

Determination of patulin in apple and hawthorn beverages by solid-phase filtration column and liquid chromatography

The use of solid-phase filtration column (MycoSep 228) and liquid chromatography for determination of patulin in apple and hawthorn beverages was investigated. The method passed a series of validation tests, including separation efficiency, sensitivity, repeatability, validation within a collaborative trial, recoveries, and applicability. Accuracy and precision were very good for determination of patulin in both spiked and naturally contaminated apple/hawthorn beverage samples at levels of 10 microg/L and above, with limits of detection and quantification at 8 and 23 [microg/L, respectively. The applicability of the method was tested by analyzing commercially available domestic apple and hawthorn beverages. Patulin was found in 3 of 52 (5.77%) apple beverages at concentrations ranging from 63.45 to 88.44 [microg/L, and in 6 of 43 (13.95%) hawthorn beverages ranging from 19.8 to 206.88 microg/L. Among these were 3 apple and 4 hawthorn beverage samples with toxin levels that exceeded the Chinese legislative requirement of 50 microg/L in apple- and hawthorn-based products intended for human consumption. Comparable tests revealed that the results obtained by both the new MycoSep-based method and the official AOAC method are not significantly different (t value = 0.003268 < to.05, P > 0.05).     

高效液相色谱法测定山楂中的苦杏仁甙

 建立了从山楂中提取苦杏仁甙的方法,样品先用石油醚脱脂，然后用甲醇进行索氏提取。用高效液相色谱法定量测定了山楂中的苦杏仁甙,色谱条件如下：反相C18柱,流动相为15%的甲醇水溶液,检测波长为215 nm。测定了含不同比例山楂籽的山楂样品,结果表明含山楂籽比例高的山楂样品中苦杏仁甙的含量高,且山楂粗粒样品中苦杏仁甙的提取量比粉末样品的提取量高。     

Fractionation of polyphenols in hawthorn into polymeric procyanidins, phenolic acids and flavonoids prior to high-performance liquid chromatographic analysis

Polymeric procyanidins, phenolic carboxylic acids and flavonoids of hawthorn (Crataegus laevigata) were fractionated prior to HPLC analysis using column chromatography and solid-phase extraction (SPE). The flavonoid fraction also contained (-)-epicatechin. The three groups of phenolics, each with clearly different UV spectra, were examined by means of high-performance liquid chromatography-diode array detection (HPLC-DAD) analysis. The average repeatability of the method (RSD) was in the range of 8-13% for chlorogenic acid, (-)-epicatechin and hyperoside. The polymeric procyanidins of hawthorn flowers consisted mainly of (-)-epicatechin subunits, and their mean degree of polymerization (DP) was 22.2. The HPLC methods developed can be used for the qualitative and quantitative analysis of different phenolic compounds in hawthorn plant material and their extracts.     

山楂挥发性化合物的气相色谱-质谱分析

采用蒸馏－萃取法收集山楂果的挥发性化合物,通过气相色谱及气相色谱／质谱分析,鉴定了３２种化合物,占总峰面积的６１％～６８％。其中主要的１０种化合物是顺－３－己烯醇、顺－３－乙酸己烯酯、α－萜品醇、糠醛、己醇、乙酸己酯、壬醛、柠檬醛、３－戊烯－２－酮,反－２－癸烯醛等。     

Capillary electrophoretic analysis of flavonoids in single-styled hawthorn (Crataegus monogyna Jacq.) ethanolic extracts

Flavonoids are an important group of natural compounds, which can prevent coronary heart disease and have antioxidant properties. Hawthorn is a well known and widely used medicinal plant due to its cardiotonic activity. Previous studies refer mostly to the HPLC analysis of the flavonoids: vitexin, quercetin, hyperoside, oligomeric procyanidins, which appear to be primarily responsible for the cardiac action of the plant. Aqueous ethanolic extracts of single-styled hawthorn (Crataegus monogyna Jacq., f.: Rosaceae Juss.) leaves and sprouts were analyzed by means of capillary zone electrophoresis (CZE). Influence of vegetation period on the extract qualitative composition and flavonoids quantities was evaluated. Sample preparation by extraction using different concentration of aqueous ethanol (40-96%, v/v) and the influence of extractant composition on the recovery of flavonoids are discussed in detail. The results obtained using CZE are compared to the results of spectrophotometric and HPLC analysis of the extracts. The effect of storage conditions of extracts (solar irradiation, temperature and duration) on degradation of flavonoids was investigated.     

Matrix solid-phase dispersion as a tool for phytochemical and bioactivities characterisation: Crataegus oxyacantha L._A case study

The use of a matrix solid-phase dispersion (MSPD) process to extract polyphenols from hawthorn (Crataegus oxyacantha L.) a deciduous shrub with an expected rich phytochemical profile, has been evaluated. MSPD extracts of fruits and leaves have an outstanding content of polyphenols, although the particular phenolic profile is solvent dependent. The extracts were analysed by HPLC-DAD for the accurate identification of the major bioactive polyphenols, some of which have never been described for this species. MSPD has proven to be a good alternative to the classic methods of obtaining natural extracts, fast and with low consumption of organic solvents, therefore, environmentally friendly. The bioactivities can be considered also very remarkable, revealing extracts with high levels of antioxidant activity.