Comprehensive Characterisation of the Ketoprofen-β-Cyclodextrin Inclusion Complex Using X-ray Techniques and NMR Spectroscopy.

Racemic ketoprofen (KP) and β-cyclodextrin (β-CD) powder samples from co-precipitation (), evaporation (), and heating-under-reflux () were analysed using X-ray techniques and nuclear magnetic resonance (NMR) spectroscopy. On the basis of NMR studies carried out in an aqueous solution, it was found that in the samples obtained by methods and there were large excesses of β-CD in relation to KP, 10 and 75 times, respectively, while the sample obtained by method contained equimolar amounts of β-CD and KP. NMR results indicated that KP/β-CD inclusion complexes were formed and the estimated binding constants were approximately 2400 M, showing that KP is quite strongly associated with β-CD.

A new computational approach to the classification of fluoroquinolones according to the Biopharmaceutical Classification System.

Background: Two main factors, which have an influence on oral absorption from solid, immediate release dosage form, are solubility and permeability. These are considered the main fundamental properties that govern the rate and extent of oral absorption. The significance of these properties has been highlighted in the Biopharmaceutics Classification System (BCS).

Physicochemical properties of lomefloxacin, levofloxacin, and moxifloxacin relevant to the biopharmaceutics classification system.

The aim of this investigation was to identify the impact of physicochemical properties of three fluoroquinolones (second, third, and fourth generation) on bioavailability in relation to the Biopharmaceutics Classification System (BCS) by in silico and in vitro methods. These properties were estimated by analyzing the electrostatic potential pattern and values of the free energy of solvation as well as the distribution coefficients and true partition coefficients of the studied compounds. This study was based on theoretical quantum-chemical methods and the in vitro shake-flask technique with two immiscible phases (n-octanol and phosphate buffer) as well as the experimental potentiometric method to estimate protonation macro- and micro-constants.

Mass spectrometry and molecular modeling studies on the inclusion complexes between alendronate and β-cyclodextrin.

Complexation of alendronate sodium (AlnNa) with β-cyclodextrin (β-CD) was studied by means of ESI-mass spectrometry. The experimental results show that stable 1:1 inclusion complexes between selected bisphosphonates and β-CD were formed. In addition, complexes with different stoichiometry were observed.

Prediction of bioavailability of selected bisphosphonates using in silico methods towards categorization into a biopharmaceutical classification system.

The physicochemical properties relevant to biological activity of selected bisphosphonates such as clodronate disodium salt, etidronate disodium salt, pamidronate disodium salt, alendronate sodium salt, ibandronate sodium salt, risedronate sodium salt and zoledronate disodium salt were determined using in silico methods. The main aim of our research was to investigate and propose molecular determinants thataffect bioavailability of above mentioned compounds. These determinants are: stabilization energy (deltaE), free energy of solvation (deltaG(solv)), electrostatic potential, dipole moment, as well as partition and distribution coefficients estimated by the log P and log D values.