King Faisal Specialist Hospital & Research Centre

About: King Faisal Specialist Hospital & Research Centre is a healthcare organization based out in Riyadh, Saudi Arabia. It is known for research contribution in the topics: Medicine & Detection limit. The organization has 58 authors who have published 157 publications receiving 3527 citations.

Chiral resolution of some piperidine 2, 6-dione drugs by high performance liquid chromatography on Kromasil CHI-DMB column.

Abstract: Kromasil CHI-DMB chiral stationary phase (CSP) is used to resolve some piperidine-2, 6-diones under normal mobile phase mode. Base-line separation was achieved using hexane and dioxane (90 : 10 v/v) for aminoglutethimide (AG), pyridoglutethimide (PG), cyclohexylaminoglutethimide (ChAG), thioglutethimide (TG), and N-acetyl aminoglutethimide (AAG). The chromatographic parameters are reported. The chiral recognition mechanisms between the analytes and the CSP depend primarily on hydrogen bonding and/or (pi-pi) interactions.

Chiral separation of several thiobarbiturates on a cellulose tris(4-methylbenzoate) phase under reversed-phase conditions

Abstract: The chiral separation of several thiobarbiturates on a tris(4-methylbenzoate) phase (Chiralcel OJ-R, 15 × 0.46 cm and Chiralcel OJ-R 15 × 0.20 cm) under reversed-phase conditions is described. The separation properties of a normal sized and a newly developed narrow-bore column were compared. The influence of buffer and organic modifiers on enantioselectvity was investigated. The three mobile phases used were water/acetonitrile (70:30,v/v), water/acetonitrile/methanol (50:25:25, v/v), and water/acetonitrile/methanol (55:15:30, v/v). Of seven thiobarbiturates investigated, five have been resolved. The values of α (1.11–1.85) and R s (0.71–5.75) have been reported.

A study of π-π interaction in high performance liquid chromatography by molecular modeling

Abstract: Molecular mechanics (MM) and molecular dynamics (MD) were used to study the π–π interaction between polynuclear aromatic hydrocarbon (PAH) and pyrene bonded silica phase. There was a good correlation coefficient (r = 0.9330, P = 2.4 × 10−4) between the logarithmic retention time (ln T r) of PAHs and −ΔG. However, there was no linearity between the retention time of substituted benzene or naphthalene compounds on pyrene bonded silica stationary phase and ΔG. Quantitative structure–retention relationship (QSRR) had been used to study the relationship of retention time and microstructure. However, by using QSRR for the substituted benzene or naphthalene derivatives, we obtained good correlation coefficient between retention time and microstructures (r 2 = 0.962, F‐test = 104.198). The MM, MD, and QSAR are very useful methods to study the π–π interaction in chromatography.

The role of ion pairing in the chromatographic study of propranolol analogues

Abstract: The partition coefficients, logP app RPLC, for a series of propranolol analogues have been determined by reversed phase high performance liquid chromatography. The hydrochloride salts and free base logP app RPLC show that charged and uncharged species can partition into the reversed phase. An extrathermodynamic relationship was found for logP app RPLC measured in two different column stationary phases, C8 and PMOS, suggesting that the same set of compounds experience a similar trend in these elution systems. The importance of using phosphate and/or MOPS buffer is due to the fact that the latter can avoid ion-pairing partitioning, but the former does play the same role for PMOS column when the free base is considered.