Anal. Sci. 3, 11-15 (1987). Description of a photoacoustic densitometry technique by laser beam scanning on a photoacoustic cell without chopping or modulation. Conversion and processing of the photoacoustic signals by microcomputer. The reproducibility of measurement for 0.03 to 0.25 µg Malachite Green was 1.7-4.5% RSD.

Realised in the systems containing binary and ternary mobile phases. Annales Universitatis Mariae Curie- Skodowska XLI 11, 120-127 (1986). Description of a graphical method for the evaluation and comparison of the resolution obtained with binary and ternary solvent mixtures. It is based on position, shape and size of two neighbouring spots and serves for the optimization of the solvent ratio. The method is demonstrated by TLC of aromatic hydrocarbons on silica with mixtures of carbon tetrachloride, benzene, chloroform, dioxane and acetone.

Chem. Anal. (N.Y.) 108, 185-196 (1990). Studies of the measurement of two-dimensional gel electrophoretic and HPTLC patterns. Presentation of two qualitative mapping techniques. Examination of quantitative analysis of partial spots using calibration curves.

Anal. Chem. 64, 3176-3179 (1992). Description of a square-wave anodic stripping voltametric method for ppm determination of heavy metals. Separation by TLC on carboxymethyl cellulose using a cellulose dialysis membrane - covered mercury film electrode placed directly on the TLC plate surface in a thin-film of supporting electrolyte solution. Presentation of the results for a mixture of Pb(II), Cd(II), and Zn(II). Calibration curves for Pb(II).

Chromatogram evaluation using video systems. BioTec 2, 28-30 (1997). State of modern video evaluation is given. The same dyestuff chromatogram is evaluated in UV and white light once by a conventional scanner and once by an electronical video system. The results are comparable. Advantages of video systems are: fast evaluation, low additional cost (if an video documentation system is already available) and later quantification of formerly documented chromatograms. Advantages of conventional scanners are: spectral selectivity, use of the whole UV range up to 190 nm, spectra recording and often a slightly better precision. (Note: The paper is not correctly reproduced by the journal - please order it from the authors directly.)

J. Chromatogr. A 898, 265-269 (2000). Presentation of a HPTLC scanner in which a special fibre arrangement is used as HPTLC plate scanning interface. Measurements are taken with a set of 50 fibres at a distance of 400-500 µm above the plate. Spatial resolution of HPTLC plate better than 160 µm. It takes less than 2 min to scan 450 spectra simultaneously in a range of 198-610 nm.

J. Chromatogr. A 1090 (1-2), 165-171 (2005). This paper presents the first study of imaging of spots on thin-layer chromatographic plates whilst still wet with solvent. Imaging and quantification of Sudan II after development with dichloromethane was carried out in both reflectance and transmission modes, using a charge coupled device (CCD) camera. The relationship between peak area and sample loading was established at low sample loading, and found to be linear over an order of magnitude for both wet and dry modes with r2-values > 0.99. All data processing was carried out using the Beer-Lambert equation. Curvature at high loadings in the plots of integrated absorbance as a function of sample loading was accounted for using an empirical expression designed for use with the Kubelka-Munk treatment and apparent absorbance of the stationary phase due to scattering. Results are consistent with an effective pathlength significantly longer than the thickness of the sorbent layer. The limit of detection on a dry plate (0.5 ng) was found to be lower than on a wetted plate (2 ng). Precision was found to be 1-4 % RSD intra-plate and 8-14 % RSD inter-plate. Results are compared with quantification of the same analyte on dried plates.

J. Planar Chromatogr. 2, 149-151 (1989). The design of an integrated CCD camera unit which is interchangeable with a modular SIMS mass spectrometer detection system is described, to measure both optical data and mass spectral data within the same planar coordinates.