Formulation and process optimization of doxorubicin-loaded PLGA nanoparticles and its in vitro release / 药学学报

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.

A new mathematical equation for the evaluation of the compression behavior of pharmaceutical materials / 药学学报

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.

Preparation of polyelectrolyte microcapsules containing ferrosoferric oxide nanoparticles / 药学学报

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).

Chitosan-coated ophthalmic submicro emulsion for pilocarpine nitrate / 药学学报

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.

Preparation of cationic dextran microspheres loaded with tetanus toxoid and study on the mechanism of protein loading / 药学学报

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.

Ion-sensitive nanoemulsion-in situ gel system for ophthalmic delivery of flurbiprofen axetil / 药学学报

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.

Preparation of polyelectrolyte microcapsules contained gold nanoparticles / 药学学报

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).

Evaluation with compression equations of compression behavior of pellets with different intragranular pore volumes / 药学学报

Microcrystalline cellulose (MCC), calcium phosphate (DCP)/MCC (4:1, w/w) and lactose (Lac)/MCC (4:1) pellets with different intragranular porosity were prepared in an extrusion-spheronizator and three volume ratios of ethanol/water were used as binder agents to prepare pellets. The compression behaviors of these pellets with different intragranular pore volume were evaluated with the parameters of Kawakita model. The results showed that high pore volume of pellets made up of MCC had the best compressibility and low pore volume of pellets had a poor compactibility. However, the compressibility of different porosity of pellets made up of DCP/MCC (4:1) or Lac/MCC (4:1) was good, but they were not significantly different. The reason might be the main compression mechanism of high porosity of MCC pellets was plastic deformation and that of DCP/MCC pellets or Lac/MCC pellets was not plastic deformation but fragmentation. These results can be observed directly by the SEM photographs. According to these results, the conclusion could be drawn that high porosity MCC pellets and different porosity DCP/MCC pellets and Lac/MCC pellets can be used as cushion granules to maintain the original shape and release characteristics of drug pellets when pellets were tabletted.

Electrophoresis and fluorospectrophotometry methods to determine the content and entrapment efficiency of siRNA in cationic liposomes / 药学学报

To develop different methods for determining siRNA content and the entrapment efficiency of siRNA loaded liposomes, SYBR Gold electrophoresis method and Ribogreen fluorospectrophotometry method were used respectively. SYBR Gold electrophoresis method has a good linear relation in a range at 0.2-2.0 micromol x L(-1) (R = 0.9930), and the recovery at the high, middle and low concentrations were 96.35%, 96.92%, and 100.74%, respectively (n = 3). The intra-day and inter-day RSD were far below 5% (n = 5). Ribogreen fluorospectrophotometry method has a good linear relation in a range at 10-50 nmol x L(-1) (R = 0.9971), and the recovery at the high, middle and low concentrations were 98.22%, 99.88% and 99.64%, respectively (n = 3). The intra-day and inter-day RSD were far below 5% (n = 5). The content and the entrapment efficiency of three batches of siRNA cationic liposomes were 98.52%, 97.85% and 99.20%, 96.45%, respectively, with these two methods. And there is no significant difference by ANOVA. Both of the two methods are accurate, sensitive, convenient method for determination of the siRNA content and the entrapment efficiency of siRNA loaded cationic liposomes.

A novel pulmonary delivery system--dry powder inhalers / 药学学报

Dry powder inhalers (DPIs) have received considerable attention because of their propellant-free composition and stability. DPIs include the DPI devices and inhalation powders. The purpose of this review is to address the development of the DPIs, including the mechanisms of absorption, the products, the devices, the preparation technology, and the characteristics.

Preparation and in vitro corneal retention behavior of novel cationic microemulsion/in situ gel system / 药学学报

The aim was to prepare a novel ocular cationic microemulsion-in situ gel (CM-ISG) system with vitamin A palmitate (VAP) as model drug, and investigate the corneal retention behavior and corneal irritation of the system. VAP/CM was prepared by a process based on supply of energy, and the before-and-after gelation rheology of VAP/CM-ISG was investigated. In vitro VAP release and gel dissolution of both VAP/CM-ISG and Oculotect Gel was determined. And in vitro corneal retention behavior of both formulations was evaluated by captive bubble technique. Ocular irritation test was carried out based on the Draize method. Images of TEM showed that homogenous VAP/CM was made, and no significant differences of particle size were found between the VAP/CM and VAP/CM in Poloxamer 407 gel. Rheology study illustrated that VAP/CM reduced the phase transition temperature of Poloxamer 407 gel by 1.5 degrees C, and the elastic modulus increased about 15.7 times. The in vitro release and gel dissolution profile of both formulations exhibited the characteristics of zero order kinetics. Comparing with Oculotect Gel, desorption kinetics study of VAP/CM-ISG exhibited longer corneal retention time and smaller contact angle. Irritation test showed a good ocular compatibility of VAP/CM-ISG. Therefore, VAP/CM-ISG combined both advantages of the cationic microemulsion and in situ gel system, provided better wettability and longer ocular retention time. It might be a promising ocular drug delivery system.

Preparation of verapamil hydrochloride core-in-cup tablets with double-pulsatile and multi-phasic release / 药学学报

To prepare verapamil hydrochloride (VH) core-in-cup tablets with tri-layered tablet and four-layered tablet as core tablets, separately, which can provide biphasic release with double-pulsatile and multi-phasic release, core tablets were prepared by direct compression method, and core-in-cup tablets by dry-compression coated technology. The parameter, time-lag (T(lag)), was used to evaluate the influence of factors, such as the weight of the top cover layer, the amount of hydroxypropylmethylcellulose (HPMC), and the compression load on VH release. With the increase of the weight and HPMC amount of the top cover layer, the first lag time T(lag1) was prolonged. The second lag time T(lag2) of core-in-cup tablet with four-layered tablet as core tablet increased with the increasing amount of HPMC K100M. With the increase of compression load among the range (6 - 10 kg x cm(-2)), the two lag times were prolonged. Core-in-cup tablets with double-pulsatile and multi-phasic release released VH after the first lag time (4 -5 h), then kept sustained release for 12 h or 13 h, finally released rapidly. The drug in the core-in-cup tablet only released from the top cover layer. T(lag) is determined by the erosion rate of the inhibitor layers (the top cover layer and the sustained-release layer of the multi-layer core tablet).

Preparation of tablets containing enteric-coated diclofenac sodium pellets / 药学学报

Fluidized-bed manufactured enteric-coated diclofenac sodium pellets were compressed into tablets. The blend of two aqueous acrylic resins dispersion in different ratios, Eudragit NE30D and Eudragit L30D-55, were used to prepare enteric-coated diclofenac sodium pellets of different particle sizes and coating level. The cushioning pellets with different properties and these enteric-coated pellets were compressed into tablets in different proportions. The drug release of the tablets containing these pellets would be lower than 10% in 2 h in simulated gastric fluid, but reach (83 +/- 2.42)% in 1 h in simulated enteric fluid. The mixture of Eudragit NE30D and Eudragit L30D-55 could be used to prepare enteric pellets which are suitable for compression. The cushioning pellets which were composed of stearic acid/microcrystalline cellulose (4:1, w/w) could avoid rupture of the coating of pellets during the compression.

Optimization of formulation of Fufang Danshen immediate release tablet by colligation score / 中国中药杂志

<p><b>OBJECTIVE</b>To optimize the formulation of immediate release tablet.</p><p><b>METHOD</b>The immediate release tablet was prepared by using dry granules. The preparation was optimized by using orthogonal design which took the flow property of granules, the hardness, the disintegrating time and the dissolution rate of the tablet as indices.</p><p><b>RESULT</b>The optimized formulation contained 40% microcrystalline cellulose, 10% sodium carboxymethyl starch and 15% dextrin. The hardness disintegrating time and T50 of the tablet were 4.5 kg, 3 min, 5 min respectively.</p><p><b>CONCLUSION</b>It is successful to prepare on immediate release tablet using the optimized formula above.</p>

Effect of absorption enhancers on nasal ginsenoside Rg1 delivery and its nasal ciliotoxicity / 药学学报

<p><b>AIM</b>The enhancing activity and safety of several absorption enhancers were evaluated as potential nasal absorption enhancers to increase intranasal absorption of ginsenoside Rg1.</p><p><b>METHODS</b>Nasal circulatory perfusion test in vivo had been employed to investigate the effect of absorption enhancers for nasal mucosa absorption of ginsenoside Rgl in rats. The safety of the absorption enhancers were evaluated by testing cilia movement of the in situ toad palate model, the hemolysis of erythrocyte membrane of the rabbit, leaching of protein and LDH from the mice nasal mucosa and the effect on cilia structural and specific cellular changes of nasal mucosa.</p><p><b>RESULTS</b>Absorption enhancers were necessary to facilitate ginsenoside Rg1 absorption by nasal mucosa. Among the absorption enhancers 1% sodium deoxycholate had great effect to facilite ginsenoside Rgl absorption by nasal mucosa; 1% dipotassium glycyrrhizinate and 1% azone had moderate effect to facilitate ginsenoside Rg1 absorption by nasal mucosa; 1% Tween-80, 2% beta-cyclodextrin, 0.5% borneol (dissolved in paraffin liquid), 0.5% chitosan, 5% hydroxypropyl-beta-cyclodextrin and 0.1% EDTA had low effect to facilitate ginsenoside Rgl absorption by nasal mucosa. 1% sodium deoxycholate, 1% azone and 1% dipotassium glycyrrhizinate had serious nasal toxicity; 1% Tween-80, 2% beta-cyclodextrin, 5% hydroxypropyl-beta-cyclodextrin had moderate nasal toxicity; 0.5% borneol (dissolved in paraffin liquid), 0.5% chitosan and 0.1% EDTA have little nasal toxicity.</p><p><b>CONCLUSION</b>0.5% borneol and 0.5% chitosan were the promising candidates having a good balance between enhancing activity and safety for nasal ginsenoside Rg1 delivery.</p>

Preparation of amylopectin modified dipyridamole liposome and its tissue distribution in mice / 药学学报

<p><b>AIM</b>To prepare amylopectin anchored dipyridamole (DIP) liposome and to study its tissue distribution in mice.</p><p><b>METHODS</b>The regular DIP liposomes were prepared by film-scatter method. The amphiphilic O-palmitoyl amylopectin was synthesized and added to modify the surface of liposome. The entrapping efficiency, zeta potential, mean diameter, span of modified and regular liposomes were assayed. The RP-HPLC was used for the determination of DIP concentration in mice tissue.</p><p><b>RESULTS</b>After modification, the entrapping efficiency depressed, zeta potential was raised, mean diameter and span had no obvious change. The level of DIP in lung, liver and spleen for regular liposomes were higher than that of injections. Compared with regular liposomes, the modified liposomes increased the DIP level in lung, and decreased the DIP level in liver, spleen, moreover, lengthened the retention time of DIP in lung.</p><p><b>CONCLUSION</b>The distribution of modified liposome in mice was markedly changed as compared with regular liposomes and injections. The modified liposomes had obvious lung targeting property.</p>

Study on evaluation index of acupoint transdermal administration--drug delivery coefficient / 中国针灸

<p><b>OBJECTIVE</b>To investigate the correlation of skin electric resistance changes with the blood drug content in acupoint transdermal administration, and to establish an new evaluation index for drug delivery efficiency through acupoints.</p><p><b>METHODS</b>Twenty-four rabbits were randomly divided into an observation group and a control group. In the observation group, aminophylline was administrated through "Feishu" (BL 13), "Geshu" (BL 17) and "Danzhong" (CV 17) which are commonly used for treatment of bronchial asthma, and the control group through sham-points on the back. The skin resistance and plasma aminophylline content were determined after application of aminophylline to the points, and their changes with time were observed. The ratio of Css/Rss at stability was defined as delivery coefficient (DC) which reflects the efficiency of delivering drug at acupoints and sham acupoints.</p><p><b>RESULTS</b>Both the plasma aminophylline and the skin resistance value tended to steady about 6-8 h after application of aminophyiophylline. The DC in the acupoints was higher than that in the sham-acupoints (P < 0.01). And there was significant difference as DC of the "Feishu"was significant difference (BL 13) and "Danzhongas DC of the "Feish" (BLCV 17) compared with that of "Geshu" (BL 17) (P < 0.01).</p><p><b>CONCLUSION</b>The bigger the DC is, the higher the efficiency of drug delivery is; the efficiency of drug delivery through acupoints is higher than that through sham-acupoints.</p>

Preparation of verapamil hydrochloride controlled-onset extended-release pellets and its pharmacokinetics in dogs / 药学学报

<p><b>AIM</b>To prepare verapamil hydrochloride controlled-onset extended-release pellets (VH-COERP) and study its release behavior in vitro. To compare the pharmacokinetic characteristics and bioavailability in six Beagle dogs after oral administration of VH-COERP and verapamil hydrochloride delayed-release pellets (VH-DRP) as reference.</p><p><b>METHODS</b>The core of VH-COERP were prepared in the fluidized bed (mini-glatt) by spraying water solution containing drugs onto sucrose-starch pellets with hydroroxy propyl methyl cellulose (HPMC) as the inner coating swelling layer and ethylcellulouse aqueous dispersion as the outer coating controlled layer. Through modifying the coating level of inner and outer layer, the VH-COERP with the optimized cumulative release profile was obtained. The concentration of VH in plasma of six dogs and its pharmacokinetic behaviors after oral administration of VH-COERP and VH-DRP at different times were studied by RP-HPLC. The pharmacokinetic parameters were computed by software program 3P97.</p><p><b>RESULTS</b>The lag time, the release behavior and the amount of VH from VH-COERP within 24 hours were not influenced by the pH of dissolution medium and post-process, but obviously influenced by the different kinds of added material in swelling layer and the coating level of the inner swelling layer and the outer controlled layer. In vitro the lag time of release profile of VH from VH-COERP was 5 h and then VH was extended release from VH-COERP in the following time. Compared with the VH-DRP, VH-COERP in vivo has an obviously lag time (4 h) , Tmax was also delayed (8 h) and the relative bioavailability was (94.56 +/- 7.64)%.</p><p><b>CONCLUSION</b>The release profile of VH from VH-COERP was shown to be extended-release after an conspicuous lag time in vitro and in vivo. So the drug can be taken by the patient before bed time and begin to work at the morning.</p>

Preparation of lung targeting azithromycin liposomes and its tissue distribution in mice / 药学学报

<p><b>AIM</b>To prepare lung targeting azithromycin cationic liposomes and to observe its tissue distribution in mice.</p><p><b>METHODS</b>The azithromycin cationic liposomes were prepared by thin film method with freeze-thawing steps. HPLC method was established and validated for the determination of azithromycin in tissues of mice.</p><p><b>RESULTS</b>The particle size of the liposomes was 6.582 microm with zeta potential of +19.5 mV. The entrapment efficiency was more than 75%. The liposomes was stable in 6 months stored at 4 degrees C. The release in vitro was characterized by Higuchi equation. Azithromycin liposomes and free azithromycin solution were injected intravenously at a dose of 80 mg x kg(-1) to mice. Compared with solution, liposomes were characterized by slower clearance, increased half-life and the AUC increased by 7.4 fold in lung.</p><p><b>CONCLUSION</b>Thin film method with freeze-thawing steps could increase the entrapment efficiency and increase the particle size of azithromycin liposomes. After modification of lipid membrane with stearylamine, the cationic liposomes were prepared. The azithromycin concentration and AUC increased in lung after iv administration to mice of the cationic liposomes. This offered a good information for preparing liposomes targeting on the lung.</p>

Evaluation of correlation between gelatin crosslinking indicators and influence factors / 药学学报

<p><b>AIM</b>To evaluate the correlation between the swelling equilibrium quantity (Seq), dissolution rate and amino group content which were used to estimate the degree of gelatin crosslinking, and the factors which influence the crosslinking, and to investigate the crosslinking mechanism of delayed dissolution of soft capsules.</p><p><b>METHODS</b>The swelling equilibrium quantity, dissolution rate and amino group content of formaldehyde-crosslinked capsule shells were determined. Gelatin structure was analyzed by means of DSC.</p><p><b>RESULTS</b>A good lineal relativity was found between the swelling equilibrium quantity, dissolution rate and amino group content (r = 0.9953-0.9985). The Seq of capsule shells was influenced by high temperature, lighting and some additives. Glycine and sodium pyrosulfite might retard the decrease of Seq of capsule shells.</p><p><b>CONCLUSION</b>The swelling equilibrium quantity, dissolution rate and amino group content exhibited the same rule in gelatin crosslinking extent. High temperature, lighting and some additives might induce gelatin crosslinking. Antioxidant such as glycine and sodium pyrosulfite might retard the crosslinking.</p>