A pH-independent instantaneous release of flurbiprofen: a study of the preparation of complexes, their characterization and in vitro/in vivo evaluation.

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.

[Preparation of valsartan nanosuspensions and its in vitro dissolution].

To increase the dissolution rate and extent of valsartan, valsartan nanosuspensions have been prepared. Controlled precipitation assisted with sonication is utilized to prepare valsartan nanosuspensions, the concentration of the drug, stabilizer and costablizer had a great effect on the stability of the preparation according to the pre-experiment. So the method of central composite design-response surface is used to optimize the prescription based on the above three factors and the particle size as the response value.

[Formulation optimization of ginkgo flavonoids matrix tablets by orthogonal design].

Sustained-release tablet has become one of the hottest research spots in the area of sustained release preparations with its unique advantages. At present, a series of shortcomings were exited in the ordinary ginkgo preparations, which were used for the treatment of cardiovascular and cerebrovascular diseases. In order to avoid these shortcomings, ginkgo flavonoids matrix tablets were prepared in this paper.

[Intestinal absorption kinetics of flurbiprofen in rats].

To study the in situ intestinal absorption kinetics of flrubiprofen in rats, the absorption of flurbiprofen in small intestine (duodenum, jejunum and ileum) and colon of rats was investigated using in situ single-pass perfusion method and the drug content was measured by HPLC. The effects of drug concentration on the intestinal absorption were investigated. The K(a) and P(app) values of flurbiprofen in the small intestine and colon had no significant difference (P > 0.

A novel small peptide as an epidermal growth factor receptor targeting ligand for nanodelivery in vitro.

The epidermal growth factor receptor (EGFR) serves an important function in the proliferation of tumors in humans and is an effective target for the treatment of cancer. In this paper, we studied the targeting characteristics of small peptides (AEYLR, EYINQ, and PDYQQD) that were derived from three major autophosphorylation sites of the EGFR C-terminus domain in vitro. These small peptides were labeled with fluorescein isothiocyanate (FITC) and used the peptide LARLLT as a positive control, which bound to putative EGFR selected from a virtual peptide library by computer-aided design, and the independent peptide RALEL as a negative control.

Further investigation of nanostructured lipid carriers as an ocular delivery system: in vivo transcorneal mechanism and in vitro release study.

This study was designed to provide further understanding of transcorneal mechanism of nanostructured lipid carriers (NLC). NLC labeled with fluorescent marker rhodamine B or coumarin-6 were produced by a melt emulsification method. By confocal laser scanning microscopy (CLSM), the interaction of NLC with corneal epithelia was traced and evaluated in rabbits in vivo.

In vitro and in vivo evaluation of gliclazide push-pull osmotic pump coated with aqueous colloidal polymer dispersions.

The objective of present work was to design and evaluate gliclazide push-pull osmotic pump (PPOP) coated with aqueous colloidal polymer dispersions-Eudragit(®) RL 30D and Eudragit(®) RS 30D. The influence of diacetin, diethyl phthalate (DEP), dibutyl sebacate (DBS) and triethyl citrate (TEC) on the free Eudragit(®) RL 30D and Eudragit(®) RS 30D films as plasticizers on drug release were studied. Among these four plasticizers, diacetin offered the smoothest surface of the cast films, and it displayed greatest water vapor transmission coefficient.

[Study on in vitro release empirical method and the release mechanism of budesonide colonic localization tablet].

The three-step dissolution experiment was established to investigate the in vitro release of budesonide colon-specific tablet and to elucidate the drug release mechanism by fitting to different mathematical models. The physiological parameters of stomach, small intestine and colon such as pH value, intestinal flora, specific organic enzyme, vermiculation and conveying time were mimicked to plot the in vitro dissolution, separately. Sample were taken at predetermined time intervals in 24 h and the accumulated drug releases were determined by using HPLC method.

[Optimization of a novel mucoadhesive drug deliver system with ion-exchange resin core loaded with berberine hydrochloride using central composite design methodology].

A novel mucoadhesive microcapsule with drug-resin complex core loaded with berberine hydrochloride (BH) was developed and optimized. Drug-ion exchange resin (IER) complex was prepared by static method which stirring IER in drug solution at certain conditions. The influences of different IERs, different temperature, pH values and concentrations of drug solution on the drug loading were investigated.

[Preparation of PEG-modified nanostructured lipid carriers loaded with hydroxycamptothecin and tissue distribution in mice].

Hydroxycamptothecin (HCPT) loaded PEG modified nanostructured lipid carriers (HCPT-PEG-NLC) and nanostructured lipid carriers (HCPT-NLC) were prepared by melt emulsification and homogenization method. The morphology, particle size and encapsulation efficiency of them were investigated. HCPT concentrations in plasma, heart, liver, spleen, lung, kidney and ovary were determined after iv of HCPT injection, HCPT-PEG-NLC and HCPT-NLC in mice.

Study on the ocular pharmacokinetics of ion-activated in situ gelling ophthalmic delivery system for gatifloxacin by microdialysis.

The poor bioavailability and therapeutic response exhibited by conventional ophthalmic solutions due to rapid precorneal elimination of the drug may be overcome by the use of gel system. The present work was conducted to evaluate the relative bioavailability of ion-activated in situ ophthalmic gel of gatifloxacin by microdialysis. The conventional ophthalmic solution of gatifloxacin was used as reference.

Preparation of budesonide-poly (ethylene oxide) solid dispersions using supercritical fluid technology.

The purpose of this study was to investigate the possibility of preparing solid dispersions of the poorly soluble budesonide by supercritical fluid (SCF) technique, using poly (ethylene oxide) (PEO) as a hydrophilic carrier. The budesonide-PEO solid dispersions were prepared, using supercritical carbon dioxide (SC CO(2)) as the processing medium, and characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), solubility test and dissolution test in order to understand the influence of the SCF process on the physical status of the drug. The endothermic peak of budesonide in the SCF-treated mixtures was significantly reduced, indicating that budesonide was in amorphous form inside the carrier system.

[Study on ingredients of essential oils of Curcuma wenyujin extracted by supercritical-CO2 fluid extraction and steam distillation].

Objective: To compare the ingredients of essential oils of Curcuma wenyujin extracted by supercritical-CO2 fluid extraction and by steam distillation.

Method: GC-MS was applied in this experiment.

Result: The ingredients and physical and chemical properties of essential oils of C.

Chitosan-based controlled porosity osmotic pump for colon-specific delivery system: screening of formulation variables and in vitro investigation.

A microbially triggered colon-targeted osmotic pump (MTCT-OP) has been studied. The gelable property at acid condition and colon-specific biodegradation of chitosan were used to: (1) produce the osmotic pressure, (2) form the drug suspension and (3) form the in situ delivery pores for colon-specific drug release, respectively. The scanning electron microscopy (SEM) study and the calculation of membrane permeability were applied to elucidate the mechanism of MTCT-OP.

Design and evaluation of jingzhiguanxin monolithic osmotic pump tablet.

A monolithic osmotic pump tablet (MOPT) of Traditional Chinese Medicine Compound Recipe (TCMCR) was successfully prepared and active components of Jingzhiguanxin prescription which has been widely used in China and Japan was selected as model drug. Analysis methods of maker compound in vitro of danshensu, paeoniflorin and safflor yellow A were built, and different methods were compared by f2 factors. The results showed that there were fine correlation among them.

Studies of the pharmacokinetics of paeoniflorin in two Jing-Zhi-Guan-Xin formulations after oral administration to beagle dogs.

Paeoniflorin is the principal bioactive component of Paeoniae Radix. The traditional chinese medicine compound recipe (TCMCR) tablets of Jing-Zhi-Guan-Xin (JZGX), which is composed of Radix Salviae Miltiorrhizae, Radix Paeoniae Rubrae, Rhizoma Chuan-xiong, Flos Carthami and Lignum Dalbergiae Odorafera, have been widely used in China and Japan. The plasma concentrations of paeoniflorin in beagle dogs after oral administration of two Jing-Zhi-Guan-Xin formulations (the dose used in the two formulations were both 200 mg paeoniflorin) were measured using a simple and rapid HPLC method.

[The pharmacokinetics and bioequivalence of acipimox sustained-release tablets after a single and multiple oral administration in healthy dogs].

Aim: To study the pharmacokinetics and bioequivalence of acipimox sustained-release tablets (SRT) after a single and multiple oral dose in healthy dogs.

Methods: The plasma concentrations of of SRT and reference capsules with a single and multiple oral doses.

Results: The drug concentration-time profiles fitted to a noncompartment model.