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酸溶ICP—AES法测定岩石,土壤样品中的硼 总被引:1,自引:0,他引:1
磷酸与许多金属有很强的络合能力,生成的磷酸盐在一定的pH值范围内易生成沉淀。本方法的特点是利用混合酸分解样品,以元素的磷酸盐沉淀分离样品中大量元素,然后用ICP-AES法测定。本方法适用于岩石,土壤样中硼的测定,其检出限0.8ng/mL。 相似文献
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介绍利用肝素亲和色谱和高效液相色谱二步法分离纯化基因重组的人血小板第四因子(rhPF4)。采用肝素柱,用含不同浓度的NaCl的磷酸盐缓冲液(sodiumphosphatbufer,即PBS)(20mmol/L,pH7.4)分级洗脱,得到初步纯化的rhPF4(纯度达80%);再采用C18柱,乙腈(含0.1%三氟醋酸即TFA)-水(含0.1%TFA)为流动相梯度洗脱,得到进一步纯化的产物。方法快速、准确、分离效果好,经过两次分离后产物纯度达95%以上。 相似文献
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本文研究了水溶性试剂1-(2-吡啶偶氮)-2-萘酚-6-磺酸(PAN-S)与铁(Ⅱ)、钴(Ⅱ)和镍(Ⅱ)之螯合物的衍生和液相色谱分离条件。在Nova-PakTMC18柱上,用含10mmol/L的pH5.0的醋酸-醋酸钠缓冲溶液的甲醇-水溶液(50:50,V/V)作流动相,溴化四丁基铵(TBA·Br)作离子对试剂,流动相流速为1.0mL/min,在550nm波长处进行光度检测。在Ⅱmin内用高效液相色谱分离测定了Fe(Ⅱ)、Co(Ⅱ)和Ni(Ⅱ)与PAN—S的螯合物,提出了离子对反相高效液相色谱快速分离测定痕量铁、钴、镍的新方法。信噪比(SNR)为2时,检测下限分别为0.043、0.007和0.012mg/L。 相似文献
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离子对高效液相色谱—TPPS4光度法测定痕量锌和铜 总被引:1,自引:1,他引:1
本文用TPPS4作柱前衍生试剂,研究了试剂与锌和铜的配位反应,在ODS柱上,用乙腈/水体系作流动相,苄基三乙基氯化铵作离子对试剂,在415nm处检测,提出了离子对高效液相色谱-光度法快速分离测定痕量锌铜的新方法,检测限:Zn和Cu分别为0.15和0.10ng/mL,本法用于花生样品中痕量Zn,Cu的测定。结果与AAS一致。 相似文献
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P Rotllán Pascual A Ramos Carrillo A Rodríguez del Castillo 《Journal of chromatography. A》1991,563(1):37-52
The reversed-phase high-performance liquid chromatographic separation of purine dinucleoside polyphosphates on octadecyl- and phenyl-bonded silica packings using phosphate-based eluents was studied. The effects of pH, ionic strength and the content of the organic modifiers methanol and acetonitrile in the mobile phase on the retention and other chromatographic parameters are reported. The data obtained were used to establish an isocratic assay for diguanosine and diadenosine polyphosphates. 相似文献
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Abstract The on-line coupling system of high-performance liquid chromatography (HPLC) and flow injection analysis (FIA) was developed for the rapid separation and sensitive detection of inorganic polyphosphates. Effects of gradient elution conditions on the chromatographic behavior were studied. The column temperature as well as a chloride concentration gradient were found to be very effective for the improvement of resolution(1). To minimize analysis time and to maximize resolution, the gradient elution conditions were optimized by use of a computer-assisted retention prediction system(2). More than 35 kinds of inorganic polyphosphates could be separated completely within 200 min under the optimum conditions as shown in Fig. 1. 相似文献
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The influence of buffer composition and pH on the electrophoretic behavior of diadenosine polyphosphates with a phosphate chain ranging from two to five phosphate groups has been examined. The electrophoretic mobility in carbonate buffer increases according to the number of phosphates, whereas in borate buffer the mobility changes in an irregular way as a function of pH. This finding can be rationalized by a well-known interaction of borate with ribose rings, which modifies the charge and the hydrodynamic radius of each diadenosine polyphosphate in a different way. Our study shows that the best separation of diadenosine polyphosphates can be achieved at the highest pH values of the range examined both in borate and carbonate buffers. 相似文献
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Jankowski J Grosse-Hüttmann P Zidek W Schlüter H 《Rapid communications in mass spectrometry : RCM》2003,17(11):1189-1194
Dinucleoside polyphosphates are a group of intra- and extracellular mediators controlling numerous physiological functions. In this study dinucleoside polyphosphates were examined by positive ion matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MADLI-TOFMS). 3-Hydroxypicolinic acid was used as UV-absorbing matrix. For the individual dinucleoside polyphosphates Ap(n)A (n = 2-7), Ap(n)G (n = 2-6) and Gp(n)G (n = 2-6), MALDI post-source decay (PSD) mass spectra were measured. Each mass peak in the MALDI-PSD mass spectra could be assigned to individual fragments of dinucleoside polyphosphates. The comparison of the fragmentation patterns of the dinucleoside polyphosphates presented here demonstrates that dinucleoside polyphosphates preferably cleave to fragment ions consisting of the corresponding mononucleoside polyphosphates as well as the corresponding nucleosides and bases during flight in the field-free drift path of the MALDI mass spectrometer. Therefore, the MALDI-PSD approach described here is suitable for identification of other dinucleoside polyphosphates. The present MALDI-PSD mass spectra may be used as MALDI-PSD mass reference spectra for future identification of dinucleoside polyphosphates and other nucleotides. 相似文献
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通过含酪氨酸的聚磷酸酯与药物分子进行大分子反应,制备了含5-氟尿嘧啶或氨甲蝶呤的聚磷酸酯。所得聚磷酸酯均具有两亲性,部分聚磷酸酯在水中能形成胶束。研究了这些聚合物的体外降解和释药性能,体外抗肿瘤实验表明,有些聚磷酸酯药物具有较强的抗肿瘤活性。 相似文献
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Naoya Ogata Kohei Sanui Masashi Harada 《Journal of polymer science. Part A, Polymer chemistry》1979,17(8):2401-2411
Direct polycondensation of various nylon salts (salts of dicarboxylic acid and diamine) took place under mild conditions in the formation of polyamide in the presence of polyphosphates and organic bases. Among organic bases imidazole was the best in terms of polymer yields. The reactivity of the polyphosphates was arranged in following order: pyrophosphate ? tripolyphosphate > tetrapolyphosphate. Otimum reaction conditions were investigated in terms of solvents, temperatures, and concentration of monomers. A reaction mechanism was proposed for the phosphorylation reaction, due to polyphosphates, which led to the direct polycondensation of nylon salts. 相似文献
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沸水阻断多聚磷酸盐分解离子色谱法检测水产品中的多聚磷酸盐 总被引:8,自引:0,他引:8
多聚磷酸盐在水产品中的快速分解影响其准确测定.用沸水破坏使多聚磷酸盐分解的物质,并用三氯甲烷去除水产品中蛋白质等杂质,离子色谱准确测定多聚磷酸盐各组分的量.实验中采用淋洗液自动发生器产生的KOH溶液作为流动相,保护柱和分离柱采用Ionpac AG11-HC和Ionpac AS11-HC抑制电导检测,可以较好地分离所检测焦磷酸根和三偏磷酸根.该方法操作简单,检出限为10 mg/kg,当水产品中添加多聚磷酸盐标准物质浓度达到10~1000 mg/kg范围时,回收率在70%~110%之间,相对标准偏差小于12% . 相似文献
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SYNTHESISANDDRUGRELEASEOFCROSSLINKINGPOLYPHOSPHATESLuoYi;ZhuoRenxi;FanChanglie(DepartmentofChemistry,WuhanUniversity,Wuhan430... 相似文献
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Separation on a Preparative Scale and Quantitative Aanalysis of Oligophosphates by Means of Liquid Chromatography New methods for the chromatographic analysis and isolation of oligophosphates have been developed. The qualitative separation has been optimized for thin layer chromatography. Quantitative analysis and isolation of the various oligophosphate species has been achieved using liquid chromatography. For ion exchange and molecular sieve-gel columns packing material, column parameters, and eluent were optimized. The on line detection system included a differential refractometer coupled to a strip chart recorder. The applicability of the technique was demonstrated by the quantitative analysis of oligophosphate mixtures. Good reproducibility and accuracy was found. It has been ascertained that the stability of polyphosphates is sufficient to allow efficient separations. 相似文献