Comprehensive evaluation of lipophilicity of biogenic amines and related compounds using different chemically bonded phases and various descriptors

Abstract

The retention behavior for a series of biogenic amines and related sympathomimetic drugs has been investigated in reversed-phase thin-layer chromatography using RP-2, RP-8, RP-18W, and Diol stationary phase and mixtures of phosphate buffer (pH = 7.10) and methanol in different proportions as mobile phases. Several methodologies like arithmetic mean of experimental retention values, extrapolation to zero methanol concentration procedure and principal component analysis were applied to retention data values (R(M)) in order to determine relevant parameters (mean of R(M) - mR(M), R(M0), and scores corresponding to the first principal component - PC1/R(M) respectively) encoding information on the lipophilic behavior of compounds. High similarities in lipophilicity behavior of investigated amines were highlighted by mR(M) and PC1/R(M) lipophilicity indices for all of the studied stationary phases. The experimental results were compared with some computed lipophilicity parameters expressed as distribution coefficients at working pH (logD), partition coefficients (logP(N), logP(I), and diff(logP(N-I))) concerning both neutral and fully protonated species and difference between both species, and also with various lipophilicity values (logP) generated by different commonly used software. Significant correlations were observed between the experimental lipophilicity indices mR(M) respectively PC1/R(M) and diff(logP(N-I) ) values in all cases.

Thin-layer chromatography-an image-processing method for the determination of acidic catecholamine metabolites

“…Because the presence and their level in biological fluids such as urine, plasma, and serum are very important in clinical diagnosis, recent studies led to important investigations concerning amine lipophilicity [1]. It is well known that the screening methods available for detecting of tumors arising in the sympathoadrenal system are based on the hyper excretions of these compounds in urine.…”

Chromatographic and computational assessment of lipophilicity using sum of ranking differences and generalized pair-correlation

“…Both, HPLC and TLC provide almost endless series of chromatographic descriptors that can be used for quantitative expression of lipophilicity [16,17]. They are derived either directly from retention data or extrapolated from linear relationships between retention and mobile phase composition.…”

Multivariate assessment of lipophilicity scales—computational and reversed phase thin-layer chromatographic indices

“…Aside from very specific applications of chromatographic approaches that tend to mimic biosystems such as micellar liquid chromatography (MLC) [10][11][12][13][14][15], immobilized artificial membrane chromatography (IAM) [16,17], immobilized proteins etc. [18], the mainstream methods in the determination of lipophilicity are still based on typical reversed-phase chromatography including a variety of chemically bonded stationary phases [19][20][21][22], where octyl-, octadecyl-, and cyanopropyl-modified silica beds are the most frequently used in combination with a polar mobile phase (usually binary mixtures of miscible organic solvents and water) [23][24][25].…”

“…the first principal component scores (PC1/R M ) derived from principal component analysis (PCA) of multivariate retention data [30,31], and arithmetic means of R M values, more frequently denoted as mR M [23][24][25].…”

“…Many procedures use similarities among computationally estimated values and experimentally derived lipophilicity indices as a criterion to select the best one. Such similarities are most often obtained from hierarchical clustering (HCA) [43,44], principal component analysis [21,23,25,45], or simple correlations based on parametric statistics such as Pearson's correlation coefficient [24,25,44]. The last one is applicable only if the data is normally distributed, which is often not the case.…”