High-performance thin layer

A simple, rapid, precise and economical High Performance Thin Layer Chromatographic (HPTLC) method has been developed and validated for determination of Alprazolam and Melatonine in its pharmaceutical preparation. It was performed on silica gel 60 Thin Layer... 

Commercially available pre-coated plates with a variety of adsorbents are generally very good for quantitative work because they are of a standard quality. Plates of a standardised silica gel 60 (as medium porosity silica gel with a mean porosity of 6mm) released by Merck have a specific surface of 500 m /g and a specific pore volume of 0.75 mL/g. They are so efficient that they have been called high performance thin layer chromatography (HPTLC) plates (Ropphahn and Halpap J Chromatogr 112 81 1975). In another variant of thin layer chromatography the... 

Janchen, D. Proc. Ini Symp. Instrum. High Perform. Thin-Layer Chromatogr. (HPTLC), 1st, Bad Durkheim, 1980,... 

Hezel, U. B., in Zlatkis, A., Kaiser, R. E. HPTLC - High Performance Thin Layer Chromatography. J. Chromatogr. Library, Vol. 9. Elsevier, Amsterdam 1977. 

E. Menziani, B. Tosi, A. Bonora, P. Reschiglian and G. Eodi, Automated multiple development high-performance thin-layer chromatographic analysis of natural phenolic compounds , 7. Chromatogr. 511 396-401 (1990). 

HIGH PERFORMANCE THIN-LAYER CHROMATOGRAPHY (HPTLC)... 

Recent developments in the practice of thin-layer chromatography have resulted in a breakthrough in performance which has led to the expression high performance thin-layer chromatography . These developments have not been the result of any specific advance in instrumentation (as with HPLC), but rather the culmination of improvements in the various operations involved in TLC. The three chief features of HPTLC are summarised below, but for a comprehensive account of the subject the reader is recommended to consult a more specialised text.59... 

High performance thin-layer chromatography has found its greatest application in the areas of clinical (e.g. analysis of drugs in blood) and environmental analysis. 

A Zlatkis and R E Kaiser (Eds), HPTLC High Performance Thin-Layer Chromatography, Elsevier, Amsterdam, 1977... 

HPTLC, high performance thin layer chromatography. 

Ritter, W. Proc. Int. Symp. Instrum High Perform Thin-Layer Chromatogr. (HPTLC), 2nd, p. 100-113, Interlaken 1982. 

The reason for this lies not least in the increasing instrumentalization and delibei automation of all those processes which were earlier particularly subject to eri (Fig. 2). Modem high performance thin-layer chromatography (HPTLC) is no Ion inferior to other liquid chromatographic techniques with respect to precision and s sitivity (Fig. 3) [6]. 

Gupta, A.P., Gupta, M.M., Kumar, S., Simultaneous determination of curcuminoids in curcuma samples using high performance thin layer chromatography, J. Liq. Chromatogr. Rel. TechnoL, 22, 1561, 1999. 

Morita et al. [69] optimized the mobile phase composition using the PRISMA model for rapid and economic determination of synthetic red pigments in cosmetics and medicines. The PRISMA model has been effective in combination with a super modihed simplex method for fadhtating optimization of the mobile phase in high performance thin layer chromatography (HPTLC). 

FIGURE 6.19 Circular chromatography of dyes on precoated silica gel high-performance TLC plate lipophilic dyes, mobile phase hexane-chloroform-NH3, 70 30. (From Ripphahn, J. and Halpaap, H., HPTLC High Performance Thin Layer Chromatography, Zlatkis, A. and Kaiser, R. E., Eds., Elsevier, Amsterdam, 1977, pp. 189-221. With permission.)... 

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