IPA Convention, 2010, RA-PO 26. HPTLC of risedronate sodium on silica gel with water - methanol - 25 % ammonia 20:3:3. Densitometric evaluation at 262 nm. The method was linear in the range of 3-6 ng/band, recovery was 98.6 %. Results were comparable with HPLC results. The advantage of the HPTLC method is the simultaneous analysis of several samples.

Chromatographia 20, 683-684 (1985). TLC of some purines on silica with iso-butanol MEK - NH3 - water 8:5:4:3 and propanol - NH3 water 16:3:1. Visualization by spraying with 1 % aqueous uranyl acetate and irradiating with UV at 254 or 366 nm. Detection limit 0.01/mg.

J .Chromatogr. Sci., 29, 210-216 (1991). Determination of the retentions of 21 5-substituted deoxyuridine derivatives on cyano-, diol- and amino-bonded silica using normal phase (dichloroethane – methanol and acetonitrile – ethyl cellosolve mixtures) and reverse-phase (water – methanol mixtures). Separation of the retention strengths (potencies) and selectivities by the spectral mapping techniques, and correlation of the potencies of the solutes with the physico-chemical parameters by using stepwise regression analysis. Discussion of the retention strength and retention selectivities of the systems for nucleoside derivatives.

J. Planar Chromatogr. 9, 31-34 (1996). HPTLC of adenine, AMP, hypoxanthine, IMP, adenosine, cAMP, inosine, xanthine on silica with water - methanol - NH3 (25%) - trichloromethane 2:9:1:9. Detection by in-situ FTIR spectroscopy.

LXXXVIII. Oxidative transformations of some pyrimidine derivatives into oxazolidine derivatives. Coll. czechoslov. chem. comm. 48, 1212-1223 (1983). TLC of the title compound on silica with a) 1-propanol - NH3 - water 7:1:2, b) chloroform - methanol - NH3 2:2:1. Detection by UV 254 nm or chlorination.

J. Chromatogr. 550, 667-675 (1991). Comparison of the log k’ values of 21 natural and synthetic deoxyuridine derivatives from HPLC with the RM values from TLC on alumina with water - 2-propanol 1:9 and 85:15, or dichloroethane - methanol - acetic acid 50:50:0.01. Discussion of the correlation between log k’ and RM values, and the influence of the length of the alkyl chain, of the substituent at position 5 of deoxyuridine on the retention. Influence of the presence of double and triple bounds in the substituent on the retention in different systems.

J. Sep. Sci. 33, 3794-3799 (2010). HPTLC of caffeine (1), theobromine (2) and theophylline (3) in different types of tea on silica gel with chloroform - dichloromethane - isopropanol 4:2:1. Quantitative determination by absorbance measurement at 254 nm. The hRF of (1), (2) and (3) was 65, 45 and 56, respectively. Limits of detection and quantification were 22 and 45 ng for (1), 23 and 46 ng for (2) and 22 and 43 ng for (3), respectively. The intra-day and inter-day precisions had a %RSD lower than 2.55 % (n=6) for all substances. Recoveries (by standard addition) were between 95.1-101.5 % for all the three methylxanthine derivatives. The values of LOD and LOQ obtained are similar with those obtained by HPLC.

J.A.O.A.C. 69, 499-503 (1986). Improvement of a spray reagent for TLC identification of uric acid: aqueous solution of ferric chloride and potassium ferricyanide, requiring neither heating nor pH control. Comparison of specificity and sensitivity to 5-10 ng of uric acid with those of other sprays. The false negative rate (at 95 % confidence interval) is 0-9.7 % for this spray compared with 0.7-18.7 % for the others.