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In this study, furbiprofen/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes were prepared to improve the drug dissolution and facilitate its application in hydrophilic gels. Inclusion complexes were prepared using a supercritical fluid processing and a conventional optimized co-lypholization method was employed as a reference. The entrapment efficacy and drug loading of both methods were investigated. Evaluation of drug dissolution enhancement was conducted in deionized water as well as buffer solutions of different pH. Carbopol 940 gels of both flurbiprofen and flurbiprofen/HPβCD inclusion complexes, with or without penetration enhancers, were prepared and percutaneous permeation studies were performed using rat abdominal skin samples. Formation of flurbiprofen/HPβCD inclusion complexes was confirmed by Fourier transform-infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. The results obtained showed that SCF processing produced a higher EE (81.91 ± 1.54%) and DL (6.96 ± 0.17%) compared with OCL with values of 69.11 ± 2.23% and 4.00 ± 1.01%, respectively. A marked instantaneous release of flurbiprofen/HPβCD inclusion complexes prepared by SCF processing (103.04 ± 2.66% cumulative release within 5 min, a 10-fold increase in comparison with flurbiprofen alone) was observed. In addition, this improvement in dissolution was shown to be pH-independent (the percentage cumulative release at pH 1.2, 4.5, 6.8 and 7.4 at 5 min was 95.19 ± 1.71, 101.75 ± 1.44, 105.37 ± 4.58 and 96.84 ± 0.56, respectively). Percutaneous permeability of flurbiprofen-in-HPβCD-in-gels could be significantly accelerated by turpentine oil and was related to the water content in the system. Anin vivopharmacokinetic study showed a 2-fold increase inCmaxand a shortenedTmaxas well as a comparable relative bioavailability when compared with the commercial flurbiprofen Cataplasms (Zepolas®). With their superior dissolution, these flurbiprofen/HPβCD inclusion complexes prepared by SCF processing could provide improved applications for flurbiprofen. [ABSTRACT FROM AUTHOR]

1-azido-2-hydroxypropyl cellulose ether, a novel potential energetic material, was prepared by reacting cellulose with glycidyl azide, which is synthesized from epihalohydrin via ring-opening and ring-closing reactions in the presence of diazoimide, under an alkaline condition, wherein a degree of substitution of the azido side chains as high as 0.5 and a nitrogen content of 10% (mass percentage) were achieved in the 1-azido-2-hydroxypropyl cellulose ether thus obtained. The structure and degree of substitution of the product were identified by characterizations such as elemental analysis, infrared absorption spectrum (IR), thermogravimetric analysis (TG), and nuclear magnetic resonance (NMR). [ABSTRACT FROM AUTHOR]