Chromatographic screening

Century, B. Vorkink, W. P. and Natelson, S. Thin layer chromatographic screening of aminoacids in plasma and urine of newborns. Clin. Chem. (1974), 20,... 

TABLE 8.2. Chromatographic Screening Methods for Prohibited Substances... 

Long AR, Crouch MD, Barker SA. 1991b. Multiresidue matrix solid phase dispersion (MSPD) extraction and gas chromatographic screening of nine chlorinated pesticides in catfish (Ictalurus punctatus) muscle tissue. J Assoc Off Anal Chem 74 667-670. 

Lott HM, Barker SA. 1993. Extraction and gas chromatographic screening of 14 chlorinated pesticides in crayfish (Procambarus clarkii) hepatopancreas. J AOAC International 76 663-668. 

L. Almela, J.A. Femandez-Lopez and M.J. Roca, High-performance liquid chromatographic screening of chlorophyll derivatives produced during fruit storage. J. Chromatogr.A 870 (2000) 483 189. 

Blake JW, Ray RS, Noonan JS, Murdick PW. 1974. Rapid, sensitive gas—liquid Chromatographic screening procedure for cocaine. Anal Chem 46 288. 

Drummer OH. 1999. Chromatographic screening techniques in systematic toxicological analysis. J Chromatogr B 733 27. 

Kuronen P, Volin P, Laitalainen T. 1998. Reversed-phase high-performance liquid chromatographic screening method for serum steroids using retention index and diode-array detection. J Chromatogr B 718(2) 211-224. 

Huang, P.Y. and Carbonell, R.G., Affinity chromatographic screening of soluble combinatorial peptide libraries, Biotechnol. Bioeng., 63, 633-641, 2000. 

PO062 Patel, R. B., C. G. Rana, M. R. Patel, PO073 H. K. Dhyani, and H. V. Chauhan. Chromatographic screening of proteins of seeds of Plantago ovata Forsk. Indian Drugs Pharm Ind 1981 16 3-5. 

WA Minnaard, J Slobodnik, JJ Vreuls, KP Hupe, UAT Brinkman. Rapid liquid-chromatographic screening of organic micropollutants in aqueous samples using a single short column for trace enrichment and separation. J Chromatogr A 696 333-340, 1995. 

B. Caddy, F. Fish, and D. Scott, Chromatographic screening for drugs of abuse using capillary columns, part 1, comparison of open tubular columns and support coated open tubular columns for the analysis of central nervous system stimulant drugs, Chro-matographia, 6 251 (1973). 

J. K. Raney, G. T. Skowronski, and R. J. Wagenhofer, Gas liquid chromatographic screening procedure for components found in clandestine phencyclidine reaction mixtures, Microgram, 77 139 (1978). 

Rapid gas chromatographic screening can be carried out using direct solvent extraction of small volumes of samples. Extractions are performed in small disposable test-tubes, and no transfer or evaporation of solvent is involved, so that drugs are not lost in the procedure. Accurate micro-pipetting and the use of internal standards enables quantification of drugs detected in serum or plasma samples. 

These cases can be most frustrating to the analyst for a negative report cannot be given when there is a most obvious detectable abnormal odour whose source has not been identified. If the material has a distinct odour, a comparative head-space gas chromatographic screen is indicated. 

This procedure employs an initial gas chromatographic screen followed by gas chromatography-mass spectrometry to provide the final confirmation. The details suggested here will cover most compounds and situations which are likely to be encountered by the toxicologist, but they may be varied to suit a particular analysis. 

Corey, E.J., Matsuda, S.P.T. and Bartel, B. (1993) Isolation oi an Arabidopsis thaliana gene encoding cycloartenol synthase by functional expression in a yeast mutant lacking lanosterol synthase by the use of a chromatographic screen. Proc. Natl. Acad. Sci. USA, 90,11628-32. 

The structural proposal 23 for this product is based on experimental proof of the constitution of rings A and B, and on mechanistic considerations (cf. Section III-B). On longer photolysis times, both compounds, 21 and 23, were consumed, and the four diastereoisomers 24-27 were isolated. According to separate irradiation experiments with each of these products, 24 and 25 on one hand, and 26 and 27 on the other are inter-convertible, with components 25 and 27 predominating in the respective photostationary equilibriums. Compound 22 yielded a very similar product mixture from which ketones 25 and 27 were isolated. Chromatographic screening indicated the presence of a product identical... 

Baker, S. A., Preparation of nfllk samples for immunoassay and liquid chromatographic screening using matrix solid-phase dispersion, JAOACInt. 77 848 (1994). 

In a paper on gas chromatographic screening of toxicological extracts for alkaloids,... 

To achieve a rapid, sensitive and relatively specific gas chromatographic screening pro-... 

Audette et al. performed a gas chromatographic screening of phaiaris species for alkaloids, mainly of the tryptamine type. Samples of 20 g dried plant material were extracted with ethanol in a Soxhlet apparatus, the ethanol was evaporated and the residue dissolved in dilute sulphuric acid. After addition of excess of ammonium hydroxide, the alkaloid bases were extracted with chloroform, and after concentration the gas chromatographic analysis was carried out on packed columns of different polarities, using Teflon tubings. After conditioning of the columns they were silanized with 10 gl of Silyl 8 (Pierce Chem. Co.). The retention times of the alkaloids on the various columns used are given in Table 17.3. 

Stuber, A., Simplified chromatographic screening test for the diagnosis of some inborn errors of metabolism. Clin. Chim. Acta 24, 221-224 (1969). 

Parker and Kirk (P2), in 1961, attempted the GLC separation of barbiturates as the free acids, using a solid support of acid-washed firebrick (apparently unsilanized). They found that the retention time varied with sample size. In a later article, Parker et al. (P3) described the use of acid-washed Chromosorb W coated with either 5% SE-30 or 1% Carbowax 20 M in an attempt to provide a gas chromatographic screening procedure for barbiturates, alkaloids, sympathomimetic amines, and tranquilizers. Their conditions probably represent a compromise, with the result that their column was not necessarily the best that could have been prepared for resolution of mixtures containing only barbiturates. 

Barker, S.A. Long, A.R. Preparation of milk samples for immunoassay and liquid chromatographic screening using matrix solid-phase dispersion. J.AOAC Int, 1994, 77, 848-854 [MSPD infant formula also albendazole, chloramphenicol, chlorsulon, chlortetracycline, fenbendazole, furazolidone, mebendazole, oxfendazole, oxytetracycUne, sulfadiazine, sulfadimethoxine, sulfamerazine, sulfa-... 

Audette, R.C.S. etal. 1969. Phytochemical investigation of Manitoba plants ii. A gas-liquid chromatographic screening technique for the identification of the alkaloids of Phalaris Journal of... 

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