No. 95 CAMAG Bibliography Service "yellow pages", Section 1 - 10

1. Reviews and books

95 001
J. QU (Qu Jianbo)*, H. LOU (Lou Hongxiang), P. FAN (Fan Peihong) (*School Pharm., Shandong Univ., Jinan 250012, China): (Application of TLC-bioautography in drug screening) (Chinese). J. Chinese Trad. and Herb. drugs 36 (1), 132-137 (2005). A review with 22 references on TLC-bioautography, including the screening of natural compounds with antibacterial and/or antifungal activity, cholinesterase inhibitors, free radical eliminators, and antioxidants. Discussion of the advantages of the technique compared to other related techniques. Traditional medicine, pharmaceutical research, herbal, qualitative identification, autoradiography, review, TLC-bioautography, antibacterial activity, antifungal activity, cholinesterase inhibition, free radical, antioxidation 1, 32

2. Fundamentals, theory and general

95 002
M. FILIP, Virginia COMAN*, R. GRECU, K. Albert, Z. MOLDOVAN (*'Raluca Ripan' Institute for Research in Chemistry, 30 Fantanele Street, P. O. Box 702, RO-400294 Cluj-Napoca, Romania): Characterization of some chemically modified acidic alumina T samples for TLC. J. Planar Chromatogr. 17, 424-430 (2004). Chemically modified acidic alumina T stationary phases have been prepared by organosilylation with the trifunctional organosilicon compounds n-octadecyltrichlorosilane, 3-mercaptopropyltrimethylsilane, and N-(2-aminomethyl)-3-aminopropyltrimethoxysilane. These chemically modified phases were characterized by elemental analysis, measurement of specific surface area, FTIR spectroscopy, 13C CP/MAS NMR spectroscopy, mass spectroscopy, and thermal analysis. The TLC behavior has been tested by separation and identification of some dyes and benzo[a]pyrene derivatives. Stationary phases 2a

95 003
H. KALÁSZ (Semmelweis University, Department of Pharmacology and Pharmacotherapy, H-1089 Budapest, Nagyvárad tér 4, Hungary): Planar displacement chromatography. J. Planar Chromatogr. 17, 464-467 (2004). Displacement chromatography (DC) has been widely used to separate metabolites with similar chemical characteristics. DC works with highly overloaded sample sizes, which are normal for samples not subjected to clean-up. DC successfully handles samples which contain high concentrations of salts and/or proteins, and results in consecutive steps of displaced compounds rather than Gaussian curves. Planar displacement chromatography (DTLC) is suitable for seeking new metabolites in excreted body fluids. Transfer of the radio labeled methyl group can easily be proven using spacer-displacement planar chromatography. Displacement TLC of L-deprenyl and 14C-L-deprenyl on silica gel with chloroform - triethanolamine 19:1. Detection by X-ray film with an exposure time of 120 h. Pharmaceutical research, autoradiography 2a, 32a

95 004
E. REICH*, A. SCHIBLI (*CAMAG Laboratory, Sonnenmattstr. 11, CH-4132 Muttenz, Switzerland): A standardized approach to modern high-performance thin-layer chromatography (HPTLC). J. Planar Chromatogr. 17, 438-443 (2004). Proposals for general standardized HPTLC methodology: 1. Plate material (consistent material, prewashing, direction of development, activation of plates, influence of relative humidity). 2. Sample application (precise and accurate volume, solvent, position, spot or bandwise application). 3. Preparation and storage of mobile phases (stability, possible reaction). 4. Development (saturation, use of a twin-trough chamber, influence of the vapor phase, distance, drying). 5. Derivatization (dipping, spraying, heating). 6. Documentation of plates. 7. Labeling (plates, images). 8. Quantitative evaluation 8. Documentation of work. HPTLC, standardization 2a

95 028
Irena BARANOWSKA et al., see section 17a

95 102
R. M. BAOSIC et al., see section 33a

95 041
Malgorzata JANICKA et al., see section 29d

95 036
M. NATIC et al., see section 24

95 044
Nada U. PERISIC-JANJIC et al., see section 29e

3. General techniques

95 005
V. G. BEREZKIN*, A. O. BALUSHKIN, E. B. NEPOKLONOV, A. V. TOPCHIEV (*Institute of Petrochemical Synthesis, Russian Academy of Sciences, Leninski pr. 29, 119991 Moscow, GSP- 1, Russia): Principles of electroosmotic circular thin-layer chromatography. J. Planar Chromatogr. 17, 476-479 (2004). Compared with traditional linear thin-layer chromatography, circular TLC is known to have three advantages: substantially better resolution, lower limits of detection (because of the concentration of the zones), and lower solvent consumption. The results obtained indicate that use of circular electroosmotic TLC (EO-TLC) made the chromatographic process both faster and more efficient. Traditional circular TLC and circular electroosmotic TLC of dyes (rhodamin 6G, brilliant green, sudan III, crystal violet) with DMSO. Electroosmotic circular thin-layer chromatography 3d

95 006
T. H. DZIDO*, J. MRÓZ, G. W. JÓZWIAK (*Department of Physical Chemistry, Medical University, Staszica 6, 20-081 Lublin, Poland): Adaptation of a horizontal DS chamber to planar electrochromatography in a closed system. J. Planar Chromatogr. 17, 404-410 (2004). Highly reproducible retention was achieved when the adsorbent layer of the plate was pre-wetted and equilibrated with the mobile phase after adaptation of a horizontal DS chamber for electrochromatography in a closed (pressurized) system. The disadvantages of the open system, evaporation of the mobile phase from the plate and excessive flow of mobile phase to the surface of the adsorbent layer during development, were eliminated. Separation of a test dye mixture on prewetted RP-8 and RP-18 phases with acetonitrile - buffer and application of a potential of 2 kV to create the electric field. Detection by scanning in reflectance mode at 420 or 254 nm. HPTLC, planar electrochromatography 3d

95 008
E. MINCSOVICS (OPLC-NIT, Andor u. 60, 1119 Budapest, Hungary): Flowing eluent wall processing OPLC: Using segmentation of non-segmented adsorbent layer for single and parallel separations. J. Planar Chromatogr. 17, 411-419 (2004). A new concept, the flowing eluent walls (FEW) process, for segmentation of a non-segmented adsorbent bed, has been used for single- and multi-channel on-line overpressured-layer chromatography, which leads to active and non-active regions on the adsorbent layer during the separation process. Mobile phase only is introduced to the non-active part of the layer whereas mobile phase and sample can be admitted to the active parts. The FEW concept provides the possibility of real multichannel liquid chromatographic separation on a non-segmented layer and column shaped adsorbent bed. Separation of chamomille oil, dye mixtures, ascorbigen standards, and cabbage extracts, were used as examples. The FEW configuration is suitable for rapid isolation of relatively large amounts of a substance. Flowing eluent walls process, OPLC 3d

95 010
Y. WANG (Yuping Wang), D. WANG* (Dongyuan Wang), J. WANG (Jie Wang), Z. XIONG ( Zhili Xiong), H. ZHANG (Hongxia Zhang), G. SHE, (Gaohong She) J. LI (Jian Li), S. XIAO (Shengtao Xiao) (*Department of Analytical Chemistry, Shenyang Pharmaceutical University, Shenyang, 110016 P. R. China): A new instrument for automated multiple development in thinlayer chromatography. J. Planar Chromatogr. 17, 290-296 (2004). Description of a new AMD instrument. Its main advantages are very low cost both of construction and in use. In comparison with ascending development in conventional instruments, a laboratory-made horizontal sandwich chamber is used for development. With the help of a series of special accessories no obvious mobile phase remains in the distributor after each step thus saving a large amount of solvent. All the components of the instrument are easy to obtain, so the average worker in the laboratory could construct the entire instrument except the control unit. An application of the instrument is described; the results obtained were satisfactory. Compared with the commercial instrument the main differences are 1) a horizontal sandwich chamber with funnel distributor is used as development chamber, 2) the most expensive component, a motor-driven valve, is omitted, 3) a micro air pump (normally used to supply oxygen for goldfish) is used to deliver mobile phase to the chamber. AMD separation of 13 dyes with first acetone - ethyl acetate 1:1 to compress the spots to slim bands, then seven steps with ethyl acetate - chloroform 4:21 to1:9 were completed; then seven steps with chloroform - cyclohexane 17:3 to 67:33. After these fifteen steps of AMD the mixture was separated into eighteen visible spots. AMD 3d

95 007
S. KHAWAS, D. PANJA, S. LASKAR* (*Natural Products Laboratory, Chemistry Department, University of Burdwan, Burdwan-713104, W. Bengal, India): A new reagent for identification of amino acids on thin-layer chromatography plates. J. Planar Chromatogr. 17, 314-315 (2004). Separation of 22 amino acids on silica gel with n-propanol - water 7:3. Detection by spraying with 1) 5 % 4-hydroxyacetophenone in acetone, followed by drying in air until all solvent had completely evaporated, and heating in an oven at 110 °C for 10 min, and, after cooling, spraying with 2) 0.4 % isatin-5-sulfonic acid (sodium salt) in ethanol - water 4:1, followed by drying in air and heating for 10 min at 110 °C. Detection limits were between 0.1 and 2 µg. 3e, 18

95 009
B. SPANGENBERG*, M. WEYANDT-SPANGENBERG (*University of Applied Sciences Offenburg, Badstrasse 24, 77652 Offenburg, Germany): Fluorescence evaluation using the Kubelka- Munk formula. J. Planar Chromatogr. 17, 164-168 (2004). HPTLC of flupirtine maleate on silica gel with ethyl acetate - methanol - 25 % ammonia 17:2:1 in a saturated developing chamber. Then the developed plate must be dipped for 2 s in 1:3 paraffin - hexane. Dipping increases the fluorescence tenfold and preserves the fluorescence stability for hours. Presentation of a new formula for transforming fluorescence measurements in accordance with Kubelka-Munk theory. The fluorescence signals, the absorption signals, and data from a selected reference are combined in one expression. Only diode-array techniques can measure all the required data simultaneously. The fluorescence calibration curve was linear over the range 300 to 5000 ng per spot. Quality control, HPTLC, densitometry, quantitative analysis, flupirtine maleate 3f, 32a

95 013
K. L. BUSCH et al., see section 4e

4. Special techniques

95 013
K. L. BUSCH (Wyvern Associates, 4201 Wilson Blvd, 110-440 Arlington, VA 22203, USA): Planar separations and mass spectrometric detection. J. Planar Chromatogr. 17, 398-403 (2004). Review divided into several sections: 'Summaries' contains a review of some recent research results in TLC-MS and PC-MS (use of a diode IR laser to desorb samples from a thin-layer chromatogram, with ionization of the desorbed gaseous molecules via a corona discharge; description of an interface between TLC and an electrospray ionization (ESI) mass spectrometer; on spot matrix-assisted laser desorption ionization (MALDI) mass spectrometry for TLC-MS); in 'Assessments and perspectives' new results are detailed, precedent and new instrumental developments are previewed; in the section 'Interconnections' synergies between mass spectrometry and different approaches to planar separations are explored. Finally, in 'Forecasts' expectations and future developments, in addition to recent techniques, are described. 11 references. Review, mass spectrometry, TLC-MS 4e, 3g

95 011
I. HAZAI (IVAX Drug Research Institute, Department for Pharmacokinetics, H-1325 Budapest, P. O. Box 82, Hungary): Use of multiple readings to increase the sensitivity of phosphor image detection in TLC. J. Planar Chromatogr. 17, 449-453 (2004). In thin-layer radiochromatography the high sensitivity of the phosphor imaging analyzer can be further increased by multiple reading of the image plates, because the latent image is not lost quantitatively in the reading process. Summing of the chromatograms obtained in successive readings results in increased signal-to-noise ratio. Thus, by use of this approach either the exposure time can be shortened or higher sensitivity can be achieved. TLC of a 14C-labeled test substance in rat serum on silica gel with chloroform - n-hexane - ethanol - ammonia 75:15:9:1. Detection by radioluminography. Radioscanning, quantitative analysis 4e

95 012
G. HORVÁTH*, L. G. SZABÓ, É. LEMBERKOVICS, L. BOTZ, B. KOCSIS (*Department of Botany, Faculty of Natural Sciences, University of Pécs, Ifjœság œtja 6, H-7624 Pécs, Hungary): Characterizaton and TLC-bioautographic detection of essential oils from some Thymus taxa, determination of the activity of the oils and their components against plant pathogenic bacteria. J. Planar Chromatogr. 17, 300-304 (2004). TLC of essential oils and thymol, carvacrol, geraniol as standards and streptomycin and gentamycin as positive controls on silica gel with toluene - ethyl acetate 93:7. Detection with ethanolic vanillin sulfuric acid. Quantitative determination at 500 nm. For bioautography the developed plates were dipped for 10 s in approximately 50 mL culture medium containing the test organism followed by drying for 2 min. After storage of the plates at 26 - 28 °C for 17 h they were dipped for 10 s in an aqueous solution (0.1 g/60 mL) of 3-{4,5-dimethylthiazol-2-yl}-2,5-diphenyltetrazolium bromide (MTT) the layers were incubated at 28 °C for 2 h and then dipped in 70 % ethanol and dried at room temperature. Herbal, qualitative identification, quantitative analysis, densitometry, Thymus 4e, 32e

95 014
H. LUFTMANN*, D. HOPPE, J. BECKER (*Organisch-Chemisches Institut, Westfälische Wilhelms- Universität, Corrensstr. 40, 48149 Münster, Germany, luftman@uni-muenster.de): Hyphenated HPTLC-MS as rapid method for elucidation of synthesis mixtures. CBS 94, 5-7 (2005). HPTLC of synthesis reaction products on silica gel with pentane - tert. butyl methyl ether 3:1 with chamber saturation. Detection by spraying with phosphomolybdic acid reagent (0.4g in 100 mL ethanol), followed by drying in hot air. Identification by online hyphenation with mass spectrometry. For online extraction with the ChromeXtract device the substance zones are eluted with methanol - chloroform 1:1 (flow rate 0.1mL/min). The outlet capillary is connected directly to the electrospray mass spectrometer (ESI-MS). Measurement in 2 s cycles in a mass range from m/z 100-600. Qualitative identification, HPTLC, ChromeXtract, TLC-MS online coupling, synthesis 4e

95 015
M. PROSEK*, L. MILIVOJEVIC, M. KRIZMAN, M. FIR (*National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia): On-line TLC-MS. J. Planar Chromatogr. 17, 420-423 (2004). A new on-line TLC-MS interface, with computer-controlled extraction of substances from selected spots on a TLC or HPTLC plate, has been constructed. The controlled collection of the sample and its programmed injection into the mass spectrometer is the advantage of this type of interface. It has been tested and validated with a standard solution of caffeine as test substance. HPTLC of caffeine on silica gel with dichloromethane - methanol 9:1. Quantification with a video-documentation system. HPTLC, TLC-MS interface 4e

95 016
W. WEBER*, W. SEITZ, Anna AICHINGER, R. ALBERT (*Zweckverband Landeswasserversorgung, Betriebs-und Forschungslaboratorium, Am Spitzigen Berg 1, D-89129 Langenau, Germany, weber.w@lw-online.de): Luminographic detection of toxicity with Vibrio fischeri (luminescent bacteria). CBS 94, 2-4 (2005). HPTLC-AMD of four pharmaceuticals and extracts of surface water on silica gel prewashed with 2-propanol (immersion for 24 h) with a 25-step gradient based on acetonitrile - formic acid - dichloromethane. Luminographic detection at ng-level by immersion of the developed HPTLC plates into Vibrio fischeri bacteria suspension. Visual evaluation with CCD-camera, exposure time 40 s, inversion and scaling of exposure in pseudocolors. To remove matrix (humic acids) from surface water samples size exclusion chromatography is recommended. Environmental, toxicology, AMD, HPTLC, qualitative identification, Vibrio fischeri, Bioluminex, luminographic detection, water analysis 4e, 37c

95 104
L. WILLIAMS et al., see section 35b

8. Substances containing heterocyclic oxygen

95 017
T. HOFMANN*, L. ALBERT, T. RÉTFALVI (*University of West Hungary, Institute for Chemistry, Ady Endre u. 5, 9400 Sopron, Hungary): Quantitative TLC analysis of (+)-catechin and (-)-epicatechin from Fagus Sylvatica L. with and without red heartwood. J. Planar Chromatogr. 17, 350-354 (2004). TLC of (+)-catechin and (-)-epicatechin on silica gel with diisopropyl ether - formic acid 9:1. Detection by spraying with vanillin-sulfuric acid reagent and heating at 120 °C for 5 min. Quantitative determination by absorbance measurement at 513 nm. Quantitative analysis, densitometry, Fagus Sylvatica, catechin, epicatechin 8a

95 018
B. LAPORNIK, Alenka GOLC WONDRA*, M. PROSEK (*National Institute of Chemistry, Laboratory for Food Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia) : Comparison of TLC and spectrophotometric methods for evaluation of the antioxidant activity of grape and berry anthocyanins. J. Planar Chromatogr. 17, 207-212 (2004). HPTLC of malvidin 3-glucoside, cyanidin 3-glucoside, delphinidin 3-glucoside, peonidin 3-glucoside, and petunidin 3-glucoside on silica gel with ethyl acetate - formic acid - twice distilled water 17:2:3 in an unsaturated twin trough chamber. After drying detection with methanolic 2,2-diphenyl-1-picrylhydrazyl reagent. Quantitative determination by videodensitometry. Food analysis, HPTLC, qualitative identification, quantitative analysis, densitometry, anthocyans 8a

95 019
Z. MALES*, M. PLAZIBAT, V. B. VUNDAC, I. ZUNTAR, K. H. PILEPIC (*Department of Pharmaceutical Botany, Faculty of Pharmacy and Biochemistry, University of Zagreb, Schrottova 39, 10000 Zagreb, Croatia): Thin-layer chromatographic analysis of flavonoids, phenolic acids, and amino acids in some Croatian Hypericum taxa. J. Planar Chromatogr. 17, 280-285 (2004). TLC of flavonoids (quercetin, I3,I8-biapigenin, quercitrin, isoquercitrin, hyperoside, rutin) and phenolic acids (caffeic and chlorogenic acid) on silica gel with ethyl acetate - formic acid - acetic acid - water 100:11:11:26 and ethyl acetate - formic acid - water 8:1:1. Detection by spraying with natural products - polyethylene glycol reagent and observation under UV light at 365 nm. Detection limit for flavonoids was 2.5 µg. Quantitative determination by spectrophotometry, calculated as quercetin. Also TLC of 16 amino acids on cellulose. Herbal, quantitative analysis, qualitative identification, Hypericum 8a, 11a, 18a, 32e

95 020
Marica MEDIC-SARIC*, I. JASPRICA, A. MORNAR, A. SMOLCIC-BUBALO, P. GOLJA (*Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Biochemistry, University of Zagreb, A. Kovacica 1, 10000 Zagreb, Croatia): Quantitative analysis of flavonoids and phenolic acids by two-dimensional thin layer chromatography. J. Planar Chromatogr. 17, 459-463 (2004). TLC of standard solutions of nine flavonoids and six phenolic acids (cinnamic, o-coumaric, m-coumaric, p-coumaric, caffeic, ferulic acid, galangin, quercetin, pinocembrin, naringenin, apigenin, chrysin, kaempferol, morin, acacetin) on silica gel in pre-saturated developing chambers with 1) n-hexane - ethyl acetate - glacial acetic acid 31:14:5, or 2) chloroform - methanol - formic acid 88:7:5. After drying, bands were visualized under short- and long-wavelength UV light. Detection by spraying with 1 % aluminium trichloride solution and evaluation under long-wavelength UV light. Standards were chromatographed again with a propolis extract. First, plates were developed with mobile phase 1 (or 2), the eluent was evaporated, standard solutions were applied again, and the plate was rotated through 90 ° and chromatographed again with mobile phase 2 (or 1). The presence (or absence) of all standards was determined according to their Rf values and fluorescence colors. Quantitative determination by absorbance measurement at 254 and 366 nm. Herbal, densitometry, quantitative analysis, qualitative identification, flavonoids, phenolics 8a

95 021
E. SOCZEWINSKI*, M. WOJCIAK-KOSIOR, G. MATYSIK (*Department of Chemistry, Medical University, Staszica 6, 20-081 Lublin, Poland): Analysis of glycosides and aglycones of flavonoid compounds by double-development thin-layer chromatography. J. Planar Chromatogr. 17, 261-263 (2004). HPTLC of aglycones and glycosides (flavone, hesperetin, naringenin, apigenin, kaempferol, quercetin, myricetin, tiliroside, apigenin 7-glucoside, myricitrin, kaempferol 3,7-dirhamnoside, hyperoside, hesperidin, rhoifolin, rutin, naringin) on silica gel by using mixtures of dichloromethane and ethyl acetate for aglycones and mixtures of ethyl acetate and formic acid for glycosides. The plates were conditioned for 15 min and developed face down in a horizontal chamber. To separate mixtures of flavonoids two-step gradient development was used. In the first step (for glycosides) the plates were developed to a distance of 65 mm with ethyl acetate - formic acid - water 170:30:1. In the second step (for aglycones) the plates were developed to a distance of 95 mm with dichloromethane - ethyl acetate - formic acid 170:30:1. Quantitation by densitometry at 254 nm. Herbal, HPTLC, densitometry, quantitative analysis, glycosides, aglycones 8a

95 022
M. WÓJCIAK-KOSIOR*, G. MATYSIK, A. SKALSKA (*Department of Chemistry, Medical Academy, Staszica 6, 20-081 Lublin, Poland): Densitometric determination of kinetics of hydrolysis of flavonoid glycosides. J. Planar Chromatogr. 17, 286-289 (2004). HPTLC of isoquercitrin, avicularin, rutin, apigenin 7-glucoside, naringin, and hesperidin on silica gel with ethyl acetate - methanol - formic acid 90:10:1. Detection under UV light at 254 nm and by spraying with 1 % methanolic diphenylboric acid beta-ethylamine ester, followed by spraying with 5 % ethanolic polyethylene glycol 4000. Quantitative determination by densitometry at 254 nm. Report of the possibilities and advantages of HPTLC for investigation of hydrolysis. Herbal, pharmaceutical research, HPTLC, densitometry, quantitative analysis, hydrolysis, flavonoid glycosides 8a

95 032
M. PROSEK et al., see section 20

10. Carbohydrates

95 023
Gerda MORLOCK*, Shashi PRABHA (*University of Hohenheim, Institute of Food Chemistry 170, Garbenstr. 28, 70599 Stuttgart, Germany, gmorlock@uni-hohenheim.de): Amino phases for derivatization of sucralose in milk-based confection. CBS 94, 14-15 (2005). HPTLC of sucralose on amino phases with acetonitrile - water 4:1 over 70 mm. Stability of sucralose in Burfi, a milk-based confection, was determined over a defined time period. The 2 products of hydrolysis have been monitored as well. Detection by heating for 20 min at 190° C. Quantitative determination by fluorescence measurement under UV 366. Limit of quantitation in the lower ng range. Food analysis, quantitative analysis, HPTLC, densitometry, sucralose 10a