1.Preparation of polyelectrolyte microcapsules contained gold nanoparticles.
Yajie SUN ; Jiabi ZHU ; Chunli ZHENG
Acta Pharmaceutica Sinica 2010;45(3):371-5
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).
2.Preparation of polyelectrolyte microcapsules containing ferrosoferric oxide nanoparticles.
Xiaoqing LIU ; Chunli ZHENG ; Jiabi ZHU
Acta Pharmaceutica Sinica 2011;46(1):115-20
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).
3.A new mathematical equation for the evaluation of the compression behavior of pharmaceutical materials.
Shengjun CHEN ; Jiabi ZHU ; Xiaole QI
Acta Pharmaceutica Sinica 2012;47(10):1384-8
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.
4.Ion-sensitive nanoemulsion-in situ gel system for ophthalmic delivery of flurbiprofen axetil.
Jinqiu SHEN ; Yong GAN ; Li GAN ; Chunliu ZHU ; Jiabi ZHU
Acta Pharmaceutica Sinica 2010;45(1):120-5
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.
5.Deposition of insulin powders for inhalation in vitro and pharmacodynamic evaluation of absorption promoters in rats
Danbo YANG ; Jiabi ZHU ; Hui ZHU ; Xusong ZHANG
Acta Pharmaceutica Sinica 2005;40(12):1069-1074
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.
6.Ion-sensitive nanoemulsion-in situ gel system for ophthalmic delivery of flurbiprofen axetil
Jinqiu SHEN ; Yong GAN ; Li GAN ; Chunliu ZHU ; Jiabi ZHU
Acta Pharmaceutica Sinica 2010;0(01):-
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.
7.Preparation of cationic dextran microspheres loaded with tetanus toxoid and study on the mechanism of protein loading.
Chunli ZHENG ; Xiaoqing LIU ; Jiabi ZHU ; Yuna ZHAO
Acta Pharmaceutica Sinica 2010;45(9):1183-7
The aim of this study is to prepare cationic biodegradable dextran microspheres loaded with tetanus toxoid (TT) and to investigate the mechanism of protein loading. Positively charged microspheres were prepared by polymerization of hydroxylethyl methacrylate derivatized dextran (dex-HEMA) and dimethyl aminoethyl methacrylate (DMAEMA) in an aqueous two-phase system. The loading of the microspheres with TT was based on electrostatic attraction. The net positive surface charge increased with increasing amounts of DMAEMA. Confocal images showed fluorescein isothiocyanate labeled bovine serum albumin (FITC-BSA) could penetrate into cationic dextran microspheres but not natural dextran microspheres. TT loading efficiency by post-loading was higher compared with by pre-loading. Even though TT is incorporated in the hydrogel network based on electrostatic interaction, still a controlled release can be achieved by varying the initial network density of the microspheres.
8.Formulation and process optimization of doxorubicin-loaded PLGA nanoparticles and its in vitro release.
Jieli LI ; Chunli ZHENG ; Jianping LIU ; Jiabi ZHU
Acta Pharmaceutica Sinica 2013;48(5):759-66
Doxorubicin-loaded PLGA nanoparticles (DOX-PLGA NPs) was prepared by double emulsion (W/O/W) solvent evaporation method with the biodegradable materials-poly (lactic-co-glycolic acid) (PLGA) used as carrier materials. Single-factor test was used to investigate the influence of the type and ratio of the organic phase, the amount of surfactant, PLGA concentration, the ratio of external water phase and oil phase (W/O), the ratio of doxorubicin and PLGA, ultrasonic time and stirring time on the preparation of nanoparticles. The best formulation and preparation conditions were optimized by orthogonal test based on single-factor test, evaluation indicator as particle size and entrapment efficiency, and the results were analyzed by overall desirability. And the in vitro release behaviors of the nanoparticles were studied as well. The size distribution, zeta potential, morphology of DOX-PLGA NPs were characterized by laser light scattering and transmission electron microscopy; encapsulation efficiency and releasing behavior of DOX-PLGA NPs in vitro were investigated by ultraviolet spectrophotometry. The results show that the DOX-PLGA NPs are regularly spherical in shape with the mean size of (189.2 +/- 5.3) nm, and the zeta-potential of the NPs is about (-28.32 +/- 0.52) mV. Drug loading and encapsulation efficiency are estimated to be (73.16 +/- 0.43) % and (1.51 +/- 0.07) %, respectively. The cumulative percentage of the drug released is 90.34%, and the in vitro release behavior made up of initial burst release and sustained-release could be described by the bidirectional kinetic equation. The results indicate that hydrophilic small-molecule drugs could be successfully entrapped into PLGA-NPs. With optimization of the formulation and preparation conditions, we obtained uniform and stable DOX-PLGA NPs with sustained release character in vitro and pH-sensitive property, which could provide the experimental basis for the development of a new anti-tumor sustained-release formulation.
9.Chitosan-coated ophthalmic submicro emulsion for pilocarpine nitrate.
Jun WEI ; Hongliang HE ; Chunli ZHENG ; Jiabi ZHU
Acta Pharmaceutica Sinica 2011;46(8):990-6
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.
10.Effect of Nimodipine Liposomes for Injection on Focal Cerebral Ischemia/Reperfusion Injury in Rats
Tianhua YAN ; Juan YANG ; Qiujuan WANG ; Zhiwei PAN ; Jiabi ZHU
International Journal of Cerebrovascular Diseases 2008;16(8):576-580
Objective:To investigate the effect of nimodipine liposomes for injection(NOLI)on focal cerebral ischemia/reperfusion(I/R)injury in rats.Methods:Seventy SD rats were divided into NDLI 1.00 mg/kg,NDLI 0.50 mg/kg,NDLI 0.25 mg/kg,nimodipine 1.00mg/kg,solvent 10 mL/kg,sham-operation and ischemic model groups.The model of middle cerelral artery occlusion in rat was replicated.The behavioral scores in rats were assessed in all groups.The infarct volume,brain water content,biochemical indices of brain homogenate and histology were detected.Results:1he NDLI 1.00mg/kg,0.50 mg/kg and 0.25 mg/kg groups could significantly improve the behavior scores in focal cerebral ischemic rats,reduce the volume of cerebral infarction,decrease the brain water content,improve the activities of Na+,K+-ATPase,Ca2+-ATPase,glutathione(GSH)and superoxide dismutazse(SOD)in brain tissues,reduce conteras of malondialdehyde(MDA),lactic acid(LA)and nitric oxide(NO),and improve histo logical injury.Conclusions:NDLI has the protective effect on focal cerebral ischemia/reperfusion injury in rats.