Computational Prediction of Diastereomeric Separation Behavior of Fluorescent o-Phthalaldehyde Derivatives of Amino Acids

Abstract

We have developed a convenient method for predicting the LC resolution of amino acid diastereomers through computational calculations. For acquiring experimental data, we derivatized 10 amino acids using o-phthalaldehyde and N-acetyl-L-cysteine as fluorogenic diastereomer-forming reagents and analyzed the diastereomers using reversed-phase LC and fluorescence detection. For theoretical chemical calculations, we used the publicly available semi-empirical calculation software MOPAC2012. Using the obtained experimental and theoretical data, we determined the change in analytical resolution with differences in the structure of the diastereomers. From the results obtained, we concluded that greater conformational change through diastereomeric derivatization induced an increase in the contact area with the stationary phase, leading to higher resolution.

Enhanced semiempirical QM methods for biomolecular interactions

“…Typical applications for SQM-DH methods include the fast optimization of molecular systems [80,81] , especially for the evaluation of experimental data [82–85] , the pre-optimization of biomolecular systems for subsequent higher-level computations [86,87] , dynamical QM studies of biomolecular systems [88–92] , and the use of SQM-DH methods as intermediate level for multilayer hybrid approaches, for instances within DFT-D/SQM-DH/MM computations [93] , or even as QM method in dynamical QM/MM simulations [94] . An application which will likely become more and more important in the future is the SQM-DH based X-ray structure refinement [95] .…”

Derivatization-based High-throughput Bioanalysis by LC-MS

“…Therefore, the determination using LC-MS/MS is recommended in such cases, although the derivatives are a fluorescent. [72][73][74][75][76] As an example, the analysis of the racemization and isomerization of N-terminal Asp in amyloid-β (Aβ) peptides in the brain homogenates of Alzheimer's disease (AD) patients were accomplished by (R)-DBD-PyNCS labeling and LC-MS/MS analysis ( Table 2). 77 The post-translational racemization and isomerization might induce the density and localization of plaque desposition in the brain tissue, because AD is related to the formation and aggregation of Aβ peptide plaques in the human brain.…”

Three-dimensional Representation Method Using Pressure, Time, and Number of Theoretical Plates to Analyze Separation Conditions in HPLC Columns

“…[1][2][3][4][5][6][7][8][9][10][11] However, it is difficult to select the optimal packing support, and to find suitable separation conditions, given a specific pressure in an HPLC system; and peripheral studies on the theory have thus far been limited. [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] In 2005, Desmet et al invented kinetic performance methods 28 by expanding both Bristow and Knox's, 29 and Poppe's 30 methods.…”