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Journal of Thermal Analysis and Calorimetry
Authors: A. Sykuła-Zając, E. Łodyga-Chruścińska, B. Pałecz, R. E. Dinnebier, U. J. Griesser, and V. Niederwanger

Molecular formula of bupivacaine hydrochloride (C 18 H 28 N 2 O·HCl, H 2 O, 342.99 g mol −1 ) The drug is still clinically available as a racemate which consists of “left-handed” S (−)- and “right-handed” R (+)- [ 3

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Molecularly imprinted polymers (MIPs) were synthesized by imprinting a new template—S(-)-1,1′-binaphthalene-2,2′-diamine (S-DABN) and applied as chiral stationary phases for chiral separation of DABN racemates by high-performance liquid chromatography (HPLC). The influence of some key factors on the chiral recognition ability of MIPs, such as the type of functional monomers and porogen and the molar ratio of template to monomer, was systematically investigated. The chromatographic conditions, such as mobile phase composition, sample loading, and flow rate, were also measured. The chiral separation for DABN racemates under the optimum chromatographic conditions by using MIP chiral stationary phase (CSP) of P3, prepared with the S-DABN/MAA ratio = 1/4 and used acetonitrile (2 mL) and chloroform (4 mL) as porogen, showed the highest separation factor (2.14). Frontal analysis was used to evaluate affinity to the target molecule of MIPs. The binding sites (B t) of MIPs and dissociation constant (K d) were estimated as 4.56 μmol g−1 and 1.40 mmol L−1, respectively. In comparison with the previous studies, this approach had the advantages, such as the higher separation factor, easy preparation, and cost-effectiveness, it not only has the value for research but also has a potential in industrial application.

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The metal-organic framework (MOF) is a kind of new type self-assembly porous coordination polymer, which possesses many characteristics such as homologic hole, controllable size of cave, high specific surface area, and good chemical stability. In this study, a three-dimensional framework [Zn2(d-Cam)2(4,4′-bpy)]n with large homochiral channel and the orderly arrangement of left- and right-handed helices was used as chiral stationary phases (CSPs) in gas chromatography (GC). [Zn2(d-Cam)2 (4,4′-bpy)]n-coated open tubular column was prepared by a dynamic coating method for high-resolution GC. Some racemates, isomers, linear alkanes, and alcohols are used as the targets for separation. The column coating properties efficiency, polarity, and selectivity were studied. The experimental results show that the stationary phase has outstanding selectivity and also possesses good recognition ability toward these compounds.

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physiological pH [ 6 ]. The pharmacokinetics of Ket is linear; at the higher recommended doses, there is a proportional increase in the concentrations of free and bound racemate. It has been observed that in humans there was very little or no interconversion of

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