The comparison of two column classification systems during the chromatographic analysis of steroids

Abstract

Nowadays, due to the availability of hundreds of brands of reversed-phase liquid chromatographic columns, the selection of suitable columns can be difficult. Therefore, a good characterization and classification system is very important. Among published papers, the classification system based on quantitative structure-retention relationships and a method developed at the Katholieke Universiteit Leuven also exist. In quantitative structure-retention relationships, retention is evaluated in terms of the chemical structure of the analytes and the physicochemical properties of both the stationary and mobile phase. The second system allows to rank columns due to the values of four parameters and the calculation of specific F(KUL)-values for a reference column and to be compared with others. In this paper, the classification systems based both on quantitative structure-retention relationships and the F(KUL)-values using principal components analysis were compared. Moreover, the proposed column ranking systems have been checked in clinical practice case considering liquid chromatography determination of six steroid hormones in urine samples. Despite that the matching of both methods is not exactly the same, both classification systems provide simple, reliable and comparable results.

Chemometric evaluation of the column classification system during the pharmaceutical analysis of lamotrigine and its related substances

“…Thus, an appropriate LC separation of lamotrigine and related compounds in accordance to the SST requirement was observed for 11 high-ranked stationary phases (11/12; 91.67 %), nine columns described by the F KUL values between 2 and 6 (9/13; 69.23 %), and none with low position in the KUL list ranking (0/3; 0 %). These results are similar to those previously found in the literature [18, 20–22, 24–28]. Moreover, the separation of lamotrigine at the concentration of 0.2 mg/mL in the presence of seven related compounds, each at the level of 0.1 % of parent substance was performed using the stationary phases examined (Fig.…”

Development of the HPLC Method for Simultaneous Determination of Lidocaine Hydrochloride and Tribenoside Along with Their Impurities Supported by the QSRR Approach

“…The literature reports many column classification systems, including the QSRR, developed to solve the analytical trouble [15–28]. In the QSRR approach, each column is characterised using sets of the regression coefficient values calculated in accordance with Eqs.…”

“…All those factors may cause that the columns will not yield satisfactory results. To overcome the problem many general test methods have been extensively investigated to characterise the RP-LC columns over the last two decades [15–28]. Among them, the QSRR based on two mathematical models seems to be an interesting approach [21–28].…”

“…To overcome the problem many general test methods have been extensively investigated to characterise the RP-LC columns over the last two decades [15–28]. Among them, the QSRR based on two mathematical models seems to be an interesting approach [21–28]. The first QSRR model relates log k w as the retention factor k of the analyte extrapolated to the virtual mobile phase of pure water or pure buffer, to the theoretically calculated logarithms of n -octanol/water partition coefficients ( c log P ) [23].…”

“…where a 1 ′ to a 4 ′ are the regression coefficients. Unfortunately, only one paper has focused on the correlation of the theoretical QSRR results and the column performance in real biomedical analyse [28]. Thus, there is the need to conduct comparative studies to investigate whether the use of the QSRR increases the probability of appropriate column selection for the specific pharmaceutical separation.…”