Current Issue : July - September Volume : 2017 Issue Number : 3 Articles : 5 Articles
Phospholipid complex is one of the most successful approaches for enhancing oral\nbioavailability of poorly absorbed plant constituents. But the sticky property of phospholipids\nresults in an unsatisfactory dissolution of drugs. In this study, a matrix dispersion of baicalein\nbased on phospholipid complex (BaPC-MD) was first prepared by a discontinuous solvent\nevaporation method, in which polyvinylpyrrolidone-K30 (PVP-K30) was employed for improving\nthe dispersibility of baicalein phospholipid complex (BaPC) and increasing dissolution of\nbaicalein. The combination ratio of baicalein and phospholipids in BaPC-MD was 99.39% and\nbaicalein was still in a complete complex state with phospholipid in BaPC-MD. Differential\nscanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and\nFourier Transform Infrared (FTIR) analyzes demonstrated that baicalein was fully transformed\nto an amorphous state in BaPC-MD and phospholipid complex formed. The water-solubility and\nn-octanol solubility of baicalein in BaPC-MD significantly increased compared with those of\npure baicalein. Compared with baicalein and BaPC, the cumulative dissolution of BaPC-MD at\n120 min increased 2.77- and 1.23-fold, respectively. In vitro permeability study in Caco-2 cells\nindicated that the permeability of BaPC-MD was remarkably higher than those of baicalein and\nBaPC. Pharmacokinetic study showed that the average Cmax of BaPC-MD was significantly\nincreased compared to baicalein and BaPC. AUC0ââ?¬â??14 h of BaPC-MD was 5.01- and 1.91-fold of\nbaicalein and BaPC, respectively. The novel BaPC-MD significantly enhanced the oral\nbioavailability of baicalein by improving the dissolution and permeability of baicalein without\ndestroying the complexation state of baicalein and phospholipids. The current drug delivery\nsystem provided an optimal strategy to significantly enhance oral bioavailability for poorly\nwater-soluble drugs....
The long-term stability of pharmaceutical formulations of poorly-soluble drugs in\npolymers determines their bioavailability and therapeutic applicability. However, these formulations\ndo not only often tend to crystallize during storage, but also tend to undergo unwanted\namorphous-amorphous phase separations (APS). Whereas the crystallization behavior of APIs in\npolymers has been measured and modeled during the last years, the APS phenomenon is still\npoorly understood. In this study, the crystallization behavior, APS, and glass-transition temperatures\nformulations of ibuprofen and felodipine in polymeric PLGA excipients exhibiting different ratios of\nlactic acid and glycolic acid monomers in the PLGA chain were investigated by means of hot-stage\nmicroscopy and DSC. APS and recrystallization was observed in ibuprofen/PLGA formulations,\nwhile only recrystallization occurred in felodipine/PLGA formulations. Based on a successful\nmodeling of the crystallization behavior using the Perturbed-Chain Statistical Associating Fluid\nTheory (PC-SAFT), the occurrence of APS was predicted in agreement with experimental findings....
Triterpene compounds like betulin, betulinic acid, erythrodiol, oleanolic acid and lupeol\nare known for many pharmacological effects. All these substances are found in the outer bark of\nbirch. Apart from its pharmacological effects, birch bark extract can be used to stabilise semisolid\nsystems. Normally, birch bark extract is produced for this purpose by extraction with organic solvents.\nEmploying supercritical fluid technology, our aim was to develop a birch bark dry extract suitable\nfor stabilisation of lipophilic gels with improved properties while avoiding the use of toxic solvents.\nWith supercritical carbon dioxide, three different particle formation methods from supercritical\nsolutions have been tested. First, particle deposition was performed from a supercritical solution in\nan expansion chamber. Second, the Rapid Expansion of Supercritical Solutions (RESS) method was\nused for particle generation. Third, a modified RESS-procedure, forming the particles directly into the\nthereby gelated liquid, was developed. All three methods gave yields from 1% to 5.8%, depending\non the techniques employed. The triterpene composition of the three extracts was comparable:\nall three gave more stable oleogels compared to the use of an extract obtained by organic solvent\nextraction. Characterizing the rheological behaviour of these gels, a faster gelling effect was seen\ntogether with a lower concentration of the extract required for the gel formation with the supercritical\nfluid (SCF)-extracts. This confirms the superiority of the supercritical fluid produced extracts with\nregard to the oleogel forming properties....
Carboxymethyl chitosan (CMCS) was synthesized and blended with gelatin (GE) to prepare\nhydrogel microspheres by w/o emulsion cross-linking in the presence of glutaraldehyde (GA), which\nacted as a cross-linker. 5-Fluorouracil (5-FU) was encapsulated to investigate its controlled release (CR)\ncharacteristics in acidic (pH 1.2) and alkaline (pH 7.4) buffer media. The microspheres which formed\nwere spherical in nature, with smooth surfaces, as judged by the scanning electron microscopy\n(SEM). Fourier transform infrared spectroscopy (FTIR) confirmed the carboxymethylation of CS\nand the chemical stability of 5-FU in the formulations. Differential scanning calorimetry (DSC)\nand X-ray diffraction (XRD) confirmed the physical state and molecular level dispersion of 5-FU.\nEquilibrium swelling of microspheres was performed in water, in order to understand the water\nuptake properties. The in vitro release of 5-FU was extended up to 12 h in pH 7.4 phosphate\nbuffer, revealing an encapsulation efficiency of 72%. The effects of blend composition, the extent of\ncross-linking, and initial drug loading on the in vitro release properties, were investigated. When\nanalyzed through empirical equations, the release data suggested a non-Fickian transport mechanism....
Novel strategies are required to manufacture customized oral solid dosage forms for\npersonalized medicine applications. 3D Pharming, the direct printing of pharmaceutical tablets,\nis an attractive strategy, since it allows for the rapid production of solid dosage forms containing\ncustom drug dosages. This study reports on the design and characterization of a biocompatible\nphotocurable pharmaceutical polymer for inkjet 3D printing that is suitable for hydrophilic active\npharmaceutical ingredients (API). Specifically, hyaluronic acid was functionalized with norbornene\nmoieties that, in the presence of poly(ethylene) glycol dithiol, Eosin Y as a photoinitiator, and a visible\nlight source, undergoes a rapid step-growth polymerization reaction through thiol-ene chemistry.\nThe engineered bioink was loaded with Ropinirole HCL, dispensed through a piezoelectric nozzle onto\na blank preform tablet, and polymerized. Drug release analysis of the tablet resulted in 60% release\nwithin 15 min of tablet dissolution. The study confirms the potential of inkjet printing for the rapid\nproduction of tablets through the deposition of a photocurable bioink designed for hydrophilic APIs....
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