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1.
离子排斥色谱法测定马齿苋中低分子羧酸   总被引:20,自引:2,他引:18  
郜志峰  刘鹏岩  傅承光 《色谱》1996,14(1):50-52
 以2.0mmol/L对甲苯磺酸为淋洗液,用非抑制型电导检测离子排斥色谱法测定了马齿苋叶及茎中的柠檬酸、丙二酸、苹果酸、抗坏血酸、琥珀酸、反丁烯二酸和乙酸。  相似文献   

2.
离子排斥色谱法同时测定果汁中11种有机酸   总被引:17,自引:0,他引:17  
郭德华  夏琳 《色谱》2001,19(3):276-278
 用离子排斥色谱法实现了对果汁中 11种有机酸 (草酸、柠檬酸、酒石酸、苹果酸、抗坏血酸、乳酸、琥珀酸、甲酸、乙酸、戊二酸、富马酸 )的分离测定。以 17mmol/L硫酸为淋洗液 ,样品在ICE ION 30 0离子排斥柱上分离后 ,用紫外检测器在 2 10nm处测定其中的有机酸。各组分质量浓度测定的相对标准偏差在 1.5 %~ 9.8% (n =10 )。  相似文献   

3.
研究了用10mmol/L的NaOH溶液超声波提取,离子色谱法同时检测烟草中有机酸和阴离子的分析方法。采用美国Dionex公司DX-500型离子色谱仪,用H2O、5mmol/L NaOH和100mmol/L NaOH梯度淋洗,流速为1.5mL/min,成功地测定了烟草中的苹果酸、柠檬酸、NO3^-1、NO2^-、Cl^-、SO4^2-等成份。这些成分在检测条件下有良好的线性关系,相关系数r^2〉0.99,检出限为0.005~0.2mg/L,相对标准偏差为0.52%。9.14%,回收率为93.5%~107.7%;实验表明该方法具有分析时间短、线性范围宽、灵敏和准确、简单快速、试剂用量少等优点。  相似文献   

4.
建立了天然水果发酵液中8种有机酸(草酸、L-酒石酸、L-苹果酸、L-乳酸、乙酸、柠檬酸、富马酸、琥珀酸)和抗坏血酸的高效液相色谱分析方法。样品经离心后过C_(18)萃取小柱净化除去色素等杂质,用Agilent ZORBAX StableBond-C_(18)反相色谱柱(4. 6 mm×250 mm,5μm)进行分离,流动相为NH_4H_2PO_4(0. 04 mol/L,pH 2. 6)-CH_3OH(V:V,99:1),检测波长为210 nm,9种目标分析物在9 min内能被很好地分离。9种目标分析物在对应的线性范围内,线性相关系数r~2均大于0. 9990,检出限为0. 034~6. 020 mg/L,回收率为91. 9%~108. 2%,相对标准偏差为2. 3%~9. 4%。该方法可应用于天然水果发酵液中有机酸和抗坏血酸的同时分析。  相似文献   

5.
本文研究了反相HPLC同时测定食物中草酸、酒石酸、苹果酸、乳酸、乙酸、柠檬酸和琥珀酸的条件,提出了用C_(18)固定相、2.5%NH_4H_2PO_4(pH2.50)溶液的流动相和在200nm下紫外检测这七种有机酸的测定方法。该法简便快速、具有较高的准确度和精密度。另外,还对有机酸的分离机理作了探讨。对十种食物中的有机酸进行了定量测定。  相似文献   

6.
建立了固相萃取-高效液相色谱法(SPE-HPLC)同时测定食品中的7种酸度调节剂(酒石酸、苹果酸、乳酸、乙酸、柠檬酸、富马酸、己二酸)含量的方法.样品经SAX强阴离子交换柱净化,高效液相色谱分析,色谱条件为采用Synergi4u Hydro-RP色谱柱,以KH2PO4缓冲溶液-乙腈(用H3PO4调PH值为3.2)为流动...  相似文献   

7.
曹家兴  杭义萍  陆建平  童张法 《色谱》2010,28(9):893-897
建立了固相萃取-离子色谱测定甘蔗糖蜜及糖蜜酒精废液中乙酸、乳酸、琥珀酸、苹果酸、酒石酸、草酸、富马酸、柠檬酸、乌头酸等非氮有机酸和盐酸根、硫酸根、磷酸根等3种无机阴离子的方法。样品稀释液经强阴离子(SAX)固相萃取小柱净化除去糖类和色素等干扰基质,再用稀KOH溶液洗脱,经0.45 μm水膜过滤后,用IonPac AS15阴离子分离柱、KOH溶液梯度淋洗-抑制电导检测分离分析。考察了固相萃取小柱对待测离子的保留和洗脱条件。实验结果表明,除乙酸和乳酸的分离不完全、苹果酸与琥珀酸的组分重叠外,其余组分可达到完全分离,被测组分的浓度与其峰高在一定的范围呈良好的线性关系,检出限均低于0.20 mg/L,相对标准偏差(RSD)小于6.7%。测定了2种甘蔗糖蜜和1种糖蜜酒精废液中有机酸及无机阴离子,结果满足检测的要求,样品中各组分的加标回收率为94%~109%。  相似文献   

8.
柠檬酸试剂中痕量无机阴阳离子的离子色谱法测定   总被引:5,自引:0,他引:5  
选用柱容量较高、亲水性较强的阴离子分析柱IonPac AS18,以30mmol/L KOH为淋洗液,等度淋洗分析了高浓度柠檬酸中的痕量无机阴离子。选用柱容量较高的阳离子分析柱IonPac CS12A,以H2SO4作淋洗液分析了柠檬酸试剂中的痕量阳离子。在所选色谱条件下,无需样品前处理,直接进样,电导检测,高浓度柠檬酸不影响痕量阴离子或阳离子的测定。方法具有良好的线性(r=0.9941~1.000),样品中所测离子峰面积的相对标准偏差(RSD)均在9.0%以下(n=7),回收率在82.7%~110%之间,检出限低于3.7μg/L。  相似文献   

9.
小麦根系中有机酸的离子色谱法分析研究   总被引:5,自引:0,他引:5  
 研究了离子交换和离子排斥法用于小麦根系中有机酸分析的色谱条件,首次建立了植物报系中有机酸的高子色谱分析方法。分别用Na_2CO_3/NaHCO_3,Na_2CO_3/NaOH和HCl作离子交换和离子排斥分高的流动相,选用化学抑制型电导检测器。对样品中柠檬酸、苹果酸、丁二酸、反丁烯二酸、乙酸、草酸的检测限为O1~0.5μg/mL,相对标准偏差为1.78%~2.97%,样品加标回收率为100±10%。  相似文献   

10.
有机酸的非抑制型离子排斥色谱法测定   总被引:2,自引:0,他引:2  
原小寓  吴伟  于泓 《分析测试学报》2008,27(1):76-78,83
研究了非抑制型离子排斥色谱分离测定7种有机酸(柠檬酸、酒石酸、苹果酸、琥珀酸、乳酸、甲酸、乙酸)的方法.以Shim-pack SCR-102H柱为分离柱,选用对甲苯磺酸-乙腈为淋洗液,考察了淋洗液浓度、流速、pH、色谱柱温度及淋洗液中乙腈含量等条件对分离和测定的影响.通过实验确定最佳的色谱条件:2.0 mmol/LP-甲苯磺酸-乙腈(体积比91:9)为淋洗液,流速1.0 mL/min,柱温50℃,pH 2.8.该法对所测有机酸的检出限在0.06~1.05.mg/L之间,相对标准偏差在3.3%以下(n=5),加标回收率在96%-101%之间,整个分析过程在11 min内完成.  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

13.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

14.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

17.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

18.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

19.
20.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

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