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牙本质中天冬氨酸消旋化程度的测定——手性毛细管气相色谱法与高效液相色谱法的比较 总被引:1,自引:0,他引:1
应用手性毛细管气相色谱法(酸性异丙醇、三氟乙酸酐为衍生试剂)、高效液相色谱法(邻苯二甲醛-N-乙酰-L-半胱氨酸为手性衍生试剂)同时测定人类第一磨牙牙本质中天冬氨酸的消旋化程度,结果表明,两者均可有效地用于天冬氨酸对映体的分离测定,但气相色谱检测限(0.2pmol)低于高效液相色谱(1.0pmol),而变异系数(7%)、总分析时间(100min)均高于高效液相色谱(分别对应为4%,31min)。 相似文献
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建立了反相高效液相色谱法测定化妆品中氯噻酮和吩噻嗪的分析方法。化妆品中氯噻酮和吩噻嗪用丙酮超声提取,采用Kromasil C18色谱柱(5μm,250 mm×4.6 mm i.d.),以30 mmol/L NaH2PO4缓冲液(pH 5.6)和甲醇为流动相进行梯度洗脱,得到了理想的分离效果。氯噻酮和吩噻嗪在0.2~100 mg/L范围内,质量浓度与其峰面积呈良好的线性关系。在低、中、高3个添加水平下,氯噻酮的平均回收率为94.8%~104.1%,RSD为0.7%~4.4%,吩噻嗪的平均回收率为92.5%~103.1%,RSD为1.0%~6.9%。方法可用于化妆品中氯噻酮和吩噻嗪的检测。 相似文献
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提出了高效液相色谱法测定海洋涂料中的吡啶硫酮锌含量的方法。涂料样品(0.020 0g)用乙酸乙酯(10mL)超声提取10min。取上清液5mL,加入0.5mol·L-1硝酸铜溶液5mL进行衍生化。以Agilent ZORBAX Eclipse XDB-C18色谱柱为分离柱,用乙腈和水以不同体积比的混合液为流动相进行梯度洗脱,用二极管阵列检测器在检测波长242nm处进行测定。吡啶硫酮锌的质量浓度在0.25~200mg·L-1范围内与其峰面积呈线性关系,检出限(3S/N)为14mg·kg-1。在3个浓度水平进行加标回收试验,回收率在89.3%~92.9%之间,测定值的相对标准偏差(n=6)均小于3.0%。 相似文献
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建立了高效液相色谱法测定营养液中吩嗪酮含量的方法,采用Aichrom Bond-AQ C18色谱柱(250 mm×4.6 mm,5μm),流动相为甲醇∶水(40∶60,V/V),流速为1.0 mL/min,检测波长为315 nm.外标法定量,吩嗪酮在1.0~200 mg/L(r=0.9996)的浓度范围内呈线性关系.方法的检出限为0.02 mg/L,回收率为96.0%~99.0%,相对标准偏差为0.20%(n=6).该方法简便、准确、易行,可用于质量控制. 相似文献
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以R(-)_4_(N,N_Dimethylaminosulfonyl)_7_(3_isothiocyanatopyrrolidino)_2,1,3_benzoxadiazole(R(-)_DBD_PyNCS)作为手性荧光衍生化试剂, 用反相高效液相色谱法(RP-HPLC)定量分析多巴胺。衍生化反应是在含有7%吡啶溶剂中, 75 ℃温度条件下, 进行40 min, 生成具有荧光特性的多巴胺衍生物(λex= 460 nm, λem= 550nm)。生成的衍生物在流动相为乙腈-水(体积比35∶65), 流速为1.0 mL/min, 在DiamonsilTM C18(150 mm×4.6mm, i.d., 5μm)色谱柱上保留时间约为15 min。多巴胺衍生物在60~1 200 ng/mL时与峰面积呈良好的线性关系(r=0.999 6), 多巴胺浓度为1 mmol/L时, 峰面积测定结果的相对标准偏差(RSD)为2.4%, 检出限为12 ng/L(S/N=3)。检测了盐酸多巴胺注射液中多巴胺的含量。 相似文献
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高效液相色谱法对手性药物罗格列酮与吡格列酮的拆分 总被引:1,自引:1,他引:0
采用高效液相色谱法,在多糖类手性固定相Chiralpak IC上成功拆分了2种降糖类手性药物罗格列酮与吡格列酮,考察了流动相、流速、温度、酸碱添加剂等对手性分离的影响.以正己烷-异丙醇(70:30,体积比)为流动相,在流速1.0 mL/min、检测波长254 nm、柱温35 ℃的条件下,罗格列酮与吡格列酮均得到良好分离,选择因子(α)分别为1.29、1.22,分离度(Rs)分别为7.07、5.56;该法不仅适用于此类手性药物的生产及质量控制,同时还可应用于对映体制备. 相似文献
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本文研究了低温条件下温度对高效液相色谱手性拆分的影响。以消旋安息香为样品,以正己烷-乙醇(70∶30,V/V)为流动相,分别用粒径为3μm、5μm、10μm的Chiralcel OD手性柱,分别在-40℃、-25℃、-10℃、5℃、20℃、35℃柱温条件下,测定了不同流速下安息香手性拆分的保留时间和柱效。根据van Deemter方程对每个温度条件下的H-u关系图进行非线性拟合,得到A、B和C三个系数与温度的关系曲线。根据手性拆分的热力学关系式,在-40℃到35℃柱温范围内,考察各色谱柱对安息香分离的lnk2′-1/T、lnα-1/T的关系均为线性。结果显示,在整个实验温度范围内,安息香在Chiralcel OD手性柱的手性拆分机理不变,降低温度能提高手性分离的选择性,但是会降低通常流速下的柱效,从而影响分离度。随着温度的降低,各色谱柱得到的van Deemter方程中系数A基本不变,系数C随着温度降低逐渐升高。 相似文献
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Ashraf Ghanem Fabienne Lacrampe Hassan Y. Aboul-Enein Volker Schurig 《Monatshefte für Chemie / Chemical Monthly》2005,136(7):1205-1219
Summary. The dirhodium(II)-catalyzed intermolecular cyclopropanation of a set of olefins with either diazo free phenyliodonium ylides or diazo compounds afforded cyclopropanes derived from Meldrum’s acid, dimethyl malonate, (silanoxyvinyl)diazoacetates, 3,3,3-trifluoro-2-diazopropionate, ethyl diazo(triethyl)- and (dimethylphenyl)silylacetate with moderate to high yield in either racemic or enantio-enriched forms. The intramolecular cyclopropanation of triethylsilyl-substituted allyl diazoacetates in the presence of the chiral rhodium(II) catalyst [Rh2(s-nttl)4] in toluene afforded the corresponding cyclopropanes with up to 37% ee. An efficient chiral separation method based on enantioselective GC and HPLC was developed. The method provides information about the chemical yields of the cyclopropane products, enantioselectivity, substrate specifity, and catalytic activity of the chiral catalysts used in the inter- and intramolecular cyclopropanation reactions and avoids time-consuming work-up procedures. 相似文献
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The γ‐aminopropyl‐derivatized silica was treated with the (R)‐(‐)‐N‐(3,5‐dinitrobenzoyl)‐α‐phenylglycine and was packed into a standard 250 mm × 4.5 mm HPLC column to perform the chiral separation of secondary alcohol. Enantiomers of four homologous series of aryl alkyl substituted alcohol were resolved in different degrees. The chiral recognition mechanism was proposed that could be used to rationalize well the elution order and the resolution between the R‐ and S‐configuration of a secondary alcohol. The unresolved peak of the enantiomers of 1‐phenylethanol and the partially resolved peak of the enantiomers of 1‐(1‐naphthyl)ethanol were deconvoluted by the assistance of computer and a program written in BASIC computer language. Two mathematical models were used for the deconvolution and were based on modified Gaussian functions with a fixed baseline that can take into account the skew of a chromatographic peak. Parameters in the mathematical model were estimated by using a nonlinear regression algorithm. The selected mathematical models were suitable for deconvolving the less skewed overlapping peaks of 1‐phenylethanol. 相似文献
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PENG Bo FU Shiguo LI Yanxia ZHANG Junhui XIE Shengming LI Li LYU Yun DUAN Aihong CHEN Xuexian YUAN Liming 《高等学校化学研究》2019,35(6):978-982
Highly-ordered inorganic chiral mesoporous silica(HOCMS) has attracted substantial interest in recent decades. High performance liquid chromatography(HPLC) is the most important approach for the separation of enantiomers and herein reported an HPLC chiral stationary phase composed of HOCMS. The column was fabricated by conventional high pressure slurry packing. Eighteen racemates, including alcohols, ketones, amines, aldehydes and organic acids, were resolved on the column. Good chiral separations of hydrobenzoin, metoprolol, propranolol hydrochloride, 4-methyl-2-pentanol, omeprazole, 2,2'-furoin and ketoprofen were obtained. The relative standard deviations for five replicate separations of racemates were 0.1%-0.16% for retention time and 1.73%-2.64% for peak areas. The results suggest that HOCMS is a promising candidate for preparation of chiral stationary phases for HPLC. 相似文献
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饲料中生物素的高效液相色谱测定 总被引:10,自引:0,他引:10
介绍了用液相色谱测定饲料中生物素的方法,探讨了流动相中缓冲液、pH值、有机溶剂等对分离的影响,确定的较佳色谱条件:HypersilODS柱,流动相为甲醇-0.1mol·L-1KH2PO4(H3PO4调pH=3.5)(体积比25∶75),流速1.0mL/min,紫外210nm检测;方法的相对标准偏差在3.5%以内,回收率在92%~102%,检出限为1mg/kg;实验表明该法简便、快速,适应性好;方法应用于饲料样品中生物素的测定,取得了很好的结果。 相似文献