In this work, polyelectrolyte microcapsules containing gold nanoparticles were prepared via layer by layer assembly. Gold nanoparticles and poly (allyamine hydrochloride) (PAH) were coated on the CaCO3 microparticles. And then EDTA was used to remove the CaCO3 core. Scanning electron microscopy (SEM) was used to characterize the surface of microcapsules. SEM images indicate that the microcapsules and the polyelectrolyte multilayer were deposited on the surface of CaCO3 microparticles. FITC-bovine serum albumin (FITC-BSA, 2 mg) was incorporated in the CaCO3 microparticles by co-precipitation. Fluorescence microscopy was used to observe the fluorescence intensity of microcapsules. The encapsulation efficiency was (34.31 +/- 2.44) %. The drug loading was (43.75 +/- 3.12) mg g(-1).

In this study, polyelectrolyte microcapsules have been fabricated by biocompatible ferrosoferric oxide nanoparticles (Fe3O4 NPs) and poly allyamine hydrochloride (PAH) using layer by layer assembly technique. The Fe3O4 NPs were prepared by chemical co-precipitation, and characterized by transmission electron microscopy (TEM) and infrared spectrum (IR). Quartz cell also was used as a substrate for building multilayer films to evaluate the capability of forming planar film. The result showed that Fe3O4 NPs were selectively deposited on the surface of quartz cell. Microcapsules containing Fe3O4 NPs were fabricated by Fe3O4 NPs and PAH alternately self-assembly on calcium carbonate microparticles firstly, then 0.2 molL(-1) EDTA was used to remove the calcium carbonate. Scanning electron microscopy (SEM), Zetasizer and vibrating sample magnetometer (VSM) were used to characterize the microcapsule's morphology, size and magnetic properties. The result revealed that Fe3O4 NPs and PAH were successfully deposited on the surface of CaCO3 microparticles, the microcapsule manifested superparamagnetism, size and saturation magnetization were 4.9 +/- 1.2 microm and 8.94 emu x g(-1), respectively. As a model drug, Rhodamin B isothiocyanate labeled bovine serum albumin (RBITC-BSA) was encapsulated in microcapsule depended on pH sensitive of the microcapsule film. When pH 5.0, drug add in was 2 mg, the encapsulation efficiency was (86.08 +/- 3.36) % and the drug loading was 8.01 +/- 0.30 mg x m(L-1).

A new mathematical equation characterizing the compression of pharmaceutical materials is presented. This equation presumed that the rate of change of the compressible volume of powder with respect to the pressure is proportional to the compressible volume. The new model provided a good fit to several model substances employing non-linear regression techniques. The validity of the model had been verified with experimental results of various pharmaceutical powders according to the Akaikes informatics criterion (AIC) and the sum of squared deviations (SS). The parameter of the new model might reflect quantitatively the fundamental compression behaviors of the powders. It had demonstrated that the proposed model could well predict the compaction characteristics of solid particles like the Kawakita model.

Aim To prepare insulin powder for inhalation by spray-drying technology, determine the deposition of the insulin powder formulation in vitro and preliminarily investigate hypoglycemic response of the dry powder with/without absorption promoters. Methods The depositions of the insulin powder for inhalation were determined by the China Pharmacopoeia 2000 version addenda XH and hypoglycemic effects were evaluated by testing serum glucose with glucose oxidase-peroxidase (GOD-PAP) method.Results The depositions of the spray-dried insulin powder for inhalation were more than 40% under significantly greater decline in blood glucose levels, while coadministration with 1% sodium caprylate, 1%effect ( P ＞ 0. 05 ). Conclusion Insulin powder for inhalation was relatively stable under various humidity pulmonary route.

The aim of the study is to prepare flurbiprofen axetil nanoemulsion-in situ gel system (FBA/NE-ISG) and observe its ocular pharmacokinetics, rheological behavior, TEM images, irritation and cornea retention. Production of nanoemulsion was based on high-speed shear and homogenization process, and then mixed with gellan gum to prepare FBA/NE-ISG. Rheological study showed that FBA/NE-ISG possesses strong gelation capacity and its viscosity and elastic modulus increases by 2 Pa*s and 5 Pa respectively when mixed with artificial tear at the ratio of 40 : 7. TEM images suggested no significant changes in particle morphology of the pre and post gelation. Good ocular compatibility of FBA/NE-ISG was testified by the irritation test based on histological examination. In vivo fluorescence imaging system was applied to investigate the characteristics of cornea retention, and the results indicated that the nanoemulsion-in situ gel (NE-ISG) prolonged the cornea retention time significantly since K(NE-ISG) (0.008 5 min(-1) was much lower compared with flurbiprofen sodium eye drops (FB-Na, 0.03% w/v) of which the K(Eye drops) was 0.105 2 min(-1), indicated that the cornea retention time of NE-ISG was prolonged significantly. Pharmacokinetics of FBA/NE-ISG in rabbit aqueous humor was studied by cornea puncture, the MRT (12.3 h) and AUC(0-12h) (126.8 microg x min x mL(-1)) of FBA/NE-ISG was 2.7 and 2.9 times higher than that of the flurbiprofen sodium eye drops respectively, which meant that the ocular bioavailability was improved greatly by the novel preparation. Therefore, FBA/NE-ISG can enhance the ocular bioavailability by prolonging drug corneal retention significantly. What's more, encapsulated by emulsion droplets prodrug flurbiprofen (FBA) instead of flurbiprofen (FB) can reduce the ocular irritation.

The aim of the study is to prepare flurbiprofen axetil nanoemulsion-in situ gel system (FBA/NE- ISG) and observe its ocular pharmacokinetics, rheological behavior, TEM images, irritation and cornea retention. Production of nanoemulsion was based on high-speed shear and homogenization process, and then mixed with gellan gum to prepare FBA/NE-ISG. Rheological study showed that FBA/NE-ISG possesses strong gelation capacity and its viscosity and elastic modulus increases by 2 Pa?s and 5 Pa respectively when mixed with artificial tear at the ratio of 40∶7. TEM images suggested no significant changes in particle morphology of the pre and post gelation. Good ocular compatibility of FBA/NE-ISG was testified by the irritation test based on histological examination. In vivo fluorescence imaging system was applied to investigate the characteristics of cornea retention, and the results indicated that the nanoemulsion-in situ gel (NE-ISG) prolonged the cornea retention time significantly since KNE-ISG (0.008 5 min-1) was much lower compared with flurbiprofen sodium eye drops (FB-Na, 0.03% w/v) of which the KEye drops was 0.105 2 min-1, indicated that the cornea retention time of NE-ISG was prolonged significantly. Pharmacokinetics of FBA/NE-ISG in rabbit aqueous humor was studied by cornea puncture, the MRT (12.3 h) and AUC0→12 h (126.8 ?g?min?mL-1) of FBA/NE-ISG was 2.7 and 2.9 times higher than that of the flrubiprofen sodium eye drops respectively, which meant that the ocular bioavailabilitywas improved greatly by the novel preparation. Therefore, FBA/NE-ISG can enhance the ocular bioavailability by prolonging drug corneal retention significantly. What’s more, encapsulated by emulsion droplets prodrug flurbiprofen (FBA) instead of flurbiprofen (FB) can reduce the ocular irritation.

Aim: To prepare novel cubosome system for effective ocular drug delivery with dexamethasone(DEX) as model drug, and investigate its pharmacokinetic profile in rabbit aqueous humor. Methods: DEX cubosomes was prepared by the method of high-pressure homogenization, and its particle size was determined by the laser particle sizer, and the microstructure observed by cryo-TEM. In addition, Draize method was used to evaluate the ocular irritation of DEX cubosomes. Finally, aqueous humor microdialysis was utilized to evaluate its pharmacokinetics in rabbits. Results: Average diameter of DEX cubosomes was about 200 nm, and the cubic structure of the particles was evident under the cryo-TEM. It was indicated by Draize scores that this dosage form exhibited excellent ocular tolerance. Results of pharmacokinetic profiles in aqueous humor showed that AUC_(0→240) and c_(max) of the rabbit group administered with DEX cubosomes were significantly higher than those of the control group( DEX sodium phosphate eye drops), with AUC_(0→240) of the formulation Fl( 10% oil content) and F2(20% oil content) is being about 1. 8 and 2. 9 times higher than those of the control group, respectively( P <0. 05). Conclusion: The novel ocular drug delivery system of DEX cubosomes was capable of increasing significantly the drug concentration in aqueous humor, and improving the ocular bioavailability.

Aim: To prepare novel aqueous polymer dispersions with high flexibility for sustained-release coating and investigate their properties. Methods: The aqueous polymer dispersions were synthesized by the emulsion polymerization. The physico-chemical properties and film-forming potential of the dispersions were investigated while the mechanical properties of the formed film and the drug release behavior when atenolol pellets were coated with the aqueous polymer dispersions were evaluated. Results: The prepared aqueous polymer dispersions (methyl methacrylate/ethyl acrylate, 1:2) were found to have proper physico-chemical properties, excellent film-forming capability and satisfying mechanical properties. It could form free film with high flexibility and low viscosity in low temperature even in absence of the plasticizer. Sustained release of atenolol pellets was achieved when the pellets were coated the polymer dispersions. 4-h and 8-h cumulative releases were more than 50% and 80%, respectively. There was no significant difference in release between pellets prior to and post compression of the coated pellets. Conclusion: The resulting aqueous polymer dispersions could be used as sustained-release coating material with high flexibility suitable for tableting.

Aim: Synthesized N-acylated chitosan(NAC) was used to anchor on the surface of plain docetaxel li-posomes( PDL) in order to to sustain drug release. Methods; NAC of low substitution degrees were prepared using hexanoic(C_6), lauric( C_(12)), and palmitic( C_(16)) anhydrides. W-palmitoyl chitosan was chosen to anchor the do-cetaxel liposomes. In vitro release profiles of conventional liposmes and the anchored liposomes was compared. Results: Hexanoic(C_6), lauric( C_(12)), and palmitic( C_(16)) -branched chitosans were synthesized. It was found that N-acylated chitosan-anchored DXL liposomes (NDL) increase stabilities of docetaxel liposomes. 70% of docetaxel was released from PDL in 24 hours but 39% from NDL Conclusion: Liposomes anchored by the low substituted N-acylated chitosan could decrease the drug release.

The study is to design chitosan-coated pilocarpine nitrate submicro emulsion (CS-PN/SE) for the development of a novel mucoadhesive submicro emulsion, aiming to prolong the precorneal retention time and improve the ocular absorption. CS-PN/SE was fabricated in two steps: firstly, pilocarpine nitrate submicro emulsion (PN/SE) was prepared by high-speed shear with medium chain triglycerides (MCT) as oil phase and Tween 80 as the main emulsifier, and then incubated with chitosan (CS) acetic solution. The preparation process was optimized by central composite design-response surface methodology. Besides the particle size, zeta potential, entrapment efficiency and micromorphology were investigated, CS-PN/SE's precorneal residence properties and miotic effect were especially studied using New Zealand rabbits as the animal model. When CS-PN/SE was administered topically to rabbit eyes, the ocular clearance and the mean resident time (MRT) of pilocarpine nitrate were found to be dramatically improved (P < 0.05) compared with PN/SE and pilocarpine nitrate solution (PNs), since the K(CS-PN/SE) was declined to 0.006 4 +/- 0.000 3 min(-1) while MRT was prolonged up to 155.4 min. Pharmacodynamics results showed that the maximum miosis of CS-PN/SE was as high as 46.3%, while the miotic response lasted 480 min which is 255 min and 105 min longer than that of PNs and PN/SE, respectively. A larger area under the miotic percentage vs time curve (AUC) of CS-PN/SE was exhibited which is 1.6 folds and 1.2 folds as much as that of PNs and PN/SE, respectively (P < 0.05). Therefore, CS-PN/SE could enhance the duration of action and ocular bioavailability by improving the precorneal residence and ocular absorption significantly.