Planar chromatography, introduction

The latest innovation is the introduction of ultra-thin silica layers. These layers are only 10 xm thick (compared to 200-250 pm in conventional plates) and are not based on granular adsorbents but consist of monolithic silica. Ultra-thin layer chromatography (UTLC) plates offer a unique combination of short migration distances, fast development times and extremely low solvent consumption. The absence of silica particles allows UTLC silica gel layers to be manufactured without any sort of binders, that are normally needed to stabilise silica particles at the glass support surface. UTLC plates will significantly reduce analysis time, solvent consumption and increase sensitivity in both qualitative and quantitative applications (Table 4.35). Miniaturised planar chromatography will rival other microanalytical techniques. 

R Scopes, Protein Purification Principles and Practice, 3rd ed (1993), Spnnger-Verlag (Berlin). Introduction to all methods of chromatography J Sherma, Anal. Chem. 62, 371R-381R (1990) Planar Chromatography. ... 

In the two decades after its introduction, TLC advanced in a number of fields. One of these was the improvement in multidimensional planar chromatography where a different chromatographic or electrophoretic technique in the second dimension follows the first dimensional chromatography. 

SCOPE OF ULTRATHIN-LAYER CHROMATOGRAPHY-MASS SPECTROMETRY LAYERS INTRODUCTION TO MINIATURIZED PLANAR CHROMATOGRAPHY... 

A new dimension in planar chromatography started in 2001 with the introduction of miniaturized ultrathin-layer chromatography (UTLC) layers. In contrast to TLC/ HPTLC layers, the different layers developed so far do not use irregular particulate... 

Due to the open planar surface of UTLC layers, especially ambient desorption- or elution-based techniques were used to transfer analytes from the layer to the ionization region (Table 9.2). In addition, MALDI applications under vacuum were reported and the introduction of the whole ultrathin layer plate was possible without any special mounting devices, due to the small plate dimension. As UTLC-MS is a very new hyphenation, only a few applications of MS detection were reported after separation of different substances on UTLC layers. In addition, desorption- or elution-based approaches for detecting analytes without a separation directly from the UTLC layer are mentioned to show the capabilities of this hyphenation technique. However, as there is no chromatography (separation), it may not be termed UTLC-MS. 

---