Analysis of inorganic compounds by paper chromatography

A Chromatographic method for the separation and detection of lead, silver, and mercury by extraction with organic solvent mixture on strips or sheets of filter paper, is described. Study of various physico-chemical factors responsible for the separation of cations has been made.

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Zusammenfassung Es wird eine chromatische Methode zur Trennung und Feststellung von Blei, Silber und Quecksilber durch Extraktion mittels Gemischen aus organischen Flüssigkeiten auf Papierstreifen beschrieben und die verschiedenen für die Trennwirkung verantwortlichen physikalisch-chemischen Faktoren werden betrachtet.

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The thanks 01 the author are due to Dr. N. Ghatak, D. So., Chemical-Examiner to the Government of Uttar Pradesh, for his keen interest in this investigation.     

Comparison of ascorbic acid and related compounds as interference suppressors in electrothermal atomic absorption spectrometry

Suppression of interferences from sodium, calcium and iron(III) chlorides by addition of ascorbic acid and related compounds was investigated for the determination of Pb, Sn, Mn, V and Mo. Absorption—time curves for these metals with and without ascorbic acid and other compounds showed that the peak appeared earlier for Pb, and later for Sn, Mn, Mo and V when ascorbic acid was present. Suppression of interferences was also achieved, but usually less effectively, by lactones, carboxylic acids, ammonium carbonate and formaldehyde. Carbon monoxide or dioxide generated by pyrolysis of the suppressors may participate in the suppression of interferences.     

反相高效液相色谱法测定叶酸及其相关物质

建立了反相高效液相色谱法对叶酸及其相关物质的分离测定方法。对叶酸原料药进行了测定,色谱柱为JASCO C18柱(250mm×4.6mmi.d.,5μm),流动相为V(0.05mol LKH2PO4):V(0.1mol LKOH)∶V(甲醇)=78∶2∶20,流速为1.0mL min,柱温为30℃。叶酸检出限为1.0ng,叶酸的质量分数为98.52%～99 87%;加标回收率为95.22%～100.83%。该法快速简捷,精密度高,重现性好,可用于叶酸的质量控制。     

Assay of 2,3-dihydroxybenzoic acid and related compounds in plant materials by high-performance liquid chromatography

Salicylic acid and its putative biosynthetic precursors were assayed isocratically by RP-HPLC with UV detection at 280 nm. Optimum resolution was provided by an HPLC mobile phase consisting of MeOH-1% aqueous HOAc (40:60, v/v), at pH 4. Furthermore, for the analysis of 2,3-dihydroxybenzoic acid (2,3-DHBA) in Catharanthus roseus cell cultures after elicitation, a mobile phase consisting of acetonitrile-1% aqueous HCOOH containing 0.25% trichloroacetic acid (1:5, v/v), at pH 2, was used. The recovery for the free form of 2,3-DHBA was about 80% after a one-step extraction of the cells. The detection limit of 2,3-DHBA was 3 microg by using saligenin as an internal standard.     

Detection of lysergic acid diethylamide, delta-9-tetrahydrocannabinol and related compounds by plasma chromatography.

Plasma chromatography as a method for ultratrace qualitative and quantitative detection of organic compounds is especially well suited for detection of gas chromatographic effluents. The optimum range of sample quantity is 10-6 to 10-12 g for detection and identification of a compound by use of its characteristic positive and negative mobility spectra. The type of reference mobility spectra produced by alkanes, aromatics, esters, halogenated compounds, nitrogenated compounds and organic acids have been previously reported. This study presents the reference mobility spectra produced for lysergic acid diethylamide (LSD), delta-9-tetrahydrocannabinol (delta-9-THC), digitoxigenin and several biochemical compounds of research significance. LSD and delat-9-THC in a mixture can be detected and identified by plasma chromatography positive mobility spectra in quantities of 10-7 g or less. All the compounds investigated in this study display strong MH-+ ions along with other ions primarily of the type (M)NO-+, (M)2H-+. None of these compounds exhibits negative mobility spectra.