共查询到10条相似文献,搜索用时 421 毫秒
1.
《Pharmaceutical development and technology》2013,18(3):385-392
This study explored the application of chitosan–alginate (CA) and chitosan–pectin (CP) complex films as drug release regulator for the preparation of multiunit controlled-release diclofenac sodium capsules. Pellets containing drug and microcrystalline cellulose, in a ratio of 3:5, were prepared in a fluidized rotary granulator. The pellets were coated with CA, CP, sodium alginate, pectin, and chitosan solutions. The pellets, equivalent to 75 mg drug, were filled into capsules. After 2 h of dissolution test in acidic medium, the amount of the drug released from any preparation was negligible. The pellets were further subject to pH 6.8 phosphate buffer. More than 80% drug release at 12 h was observed with the uncoated pellets and those coated with sodium alginate, pectin or chitosan. Both 1% CA and 3% CP coated pellets exhibited drug release profiles similar to that of Voltaren SR75. It was found that approximately 60% and 85% of the drug were released at 12 and 24 h, respectively. Both Differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR) analyses revealed complex formation between chitosan and these anionic polymers. It could be concluded that CA and CP complex film could be easily applied to diclofenac sodium pellets to control the release of the drug. 相似文献
2.
3.
Filipović-Grcić J Perissutti B Moneghini M Voinovich D Martinac A Jalsenjak I 《The Journal of pharmacy and pharmacology》2003,55(7):921-931
In this study, the potential of the spray-drying technique for preparing microspheres able to modify the release profile of carbamazepine was investigated. Low-, medium- and high-molecular-weight chitosan and hydroxypropyl methylcellulose (HPMC) in different drug-polymer ratios were used for the preparation of microspheres. The microspheres, characterized by X-ray powder diffractometry (XRD) and differential scanning calorimetry (DSC), were also studied with respect to particle size distribution, drug content and drug release. The results indicated that the entrapment efficiency (EE), as well as carbamazepine release profile, depended on polymeric composition and drug-polymer ratios of the microspheres prepared. The best entrapment efficiencies were obtained when chitosan of low-molecular-weight (CL) or HPMC were used for the microencapsulation. For all types of polymer used, the microspheres with low carbamazepine loading (6.3% w/w) showed better control of drug release than the microspheres with higher drug loadings. The HPMC microspheres showed the slowest carbamazepine release profile with no initial burst effect. Carbamazepine release profiles from ternary systems, carbamazepine-CL-HPMC microspheres, depended mostly on HPMC content and showed similar carbamazepine release profile as CL microspheres when HPMC content was low (9:1 CL-HPMC ratio, w/w). Otherwise, the carbamazepine release from CL-HPMC microspheres was remarkably faster than from either chitosan or HPMC microspheres. The release profile of carbamazepine from the microspheres was highly correlated with the crystalline changes occurring in the matrix. 相似文献
4.
Silvia Rossi Marzia Marciello Giuseppina Sandri Franca Ferrari Maria Cristina Bonferoni Adele Papetti 《Pharmaceutical development and technology》2013,18(4):415-422
In the present work wound dressings, based on chitosan hydrochloride (HCS), 5-methyl-pyrrolidinone chitosan (MPC), and their mixtures with an anionic polymer, hyaluronic acid (HA), were prepared by freeze-drying. Chlorhexidine diacetate (CX) was used as an antimicrobic drug. The mechanical properties of the wound dressings were investigated. In particular, the wound dressings were subjected to dynamic hydration measurements to evaluate their capability to absorb wound exudate and to rheological analysis to investigate their resistance to mechanical stresses on hydration. The wound dressings were also characterized for drug release properties. The antioxidant and antimicrobial activities of medicated and non-medicated wound dressings were also investigated. All the wound dressings are characterized by mechanical resistance suitable for skin application. The addition of hyaluronic acid to chitosans leads to a reduction in wound dressing hydration properties and a modulation of drug release. The wound dressing based on MPC is characterized by the highest elastic properties and by the best scavenger activity. Antimicrobial activity against bacteria and C. albicans is shown by the dressing based on chitosan also in absence of chlorhexidine. 相似文献
5.
Preparation and in vitro evaluation of mucoadhesive properties of alginate/chitosan microparticles containing prednisolone 总被引:3,自引:0,他引:3
Wittaya-areekul S Kruenate J Prahsarn C 《International journal of pharmaceutics》2006,312(1-2):113-118
This study describes the preparation of mucoadhesive alginate/chitosan microparticles containing prednisolone intended for colon-specific delivery. Two methods have been used for the preparation of the particles: the one-step method is the method in which prednisolone was dispersed within sodium alginate solution and this dispersion was then dropped in a solution containing both calcium chloride and chitosan. The two-step method consisted also of the dispersion of prednisolone in alginate solution and then dropping this dispersion into a solution containing calcium chloride, the particles were then transferred to a chitosan solution. The concentration of sodium alginate solution at 2% (w/v), various concentrations of calcium chloride solution (0.5-1.0%, w/v), chitosan solutions (0.5, 1.0 and 1.5%, w/v) and prednisolone drug load (2, 5, 10 and 15%, w/v) have been used. The results for both preparation methods show that the particle size and drug content were mainly depending on the amount of the drug concentration and not the amount of chitosan and calcium chloride. The in vitro mucoadhesive tests for particles prepared from both methods were carried out using the freshly excised gut of pigs. The particles prepared by the one-step method exhibited excellent mucoadhesive properties after 1h test. Increased chitosan concentrations from 0, 0.5, 1.0 to 1.5% (w/v) resulted in 43, 55, 82 and 88% of the particle remaining attached on the gut surface after 1 h, respectively. However, the particles prepared by the two-step method showed significant less mucoadhesion under the same experimental conditions. At chitosan concentrations of 0, 0.5, 1.0 and 1.5% (w/v) the amount of particles remaining attached to the mucosal surface of the pig gut after 1 h was 43, 3, 11 and 11%, respectively. The prednisolone release at a pH of 6.8 after 4 h was between 63 and 79% for the particles prepared by the one-step method and between 57 and 88% for the particles prepared by the two-step method with a prednisolone drug load of 5 and 10% (w/v), respectively. The results show that depending on the preparation method these chitosan coated alginate particles show different mucoadhesiveness whereas their other properties are not statistically significant different. 相似文献
6.
Turbidimetric titration revealed that there were electrostatic attractive interactions between citrate and chitosan in the pH region of 4.3-7.6, depending on their degree of ionization. Citrate cross-linked chitosan film was prepared simply by dipping chitosan film into sodium citrate solution. The swelling ratio of citrate/chitosan film was sensitive to pH, ionic strength etc. Under acidic conditions, citrate/chitosan film swelled and even dissociated in the pH less than 3.5, and the model drugs (brilliant blue and riboflavin) incorporated in the film were released quickly (usually within 2 h released completely in simulated gastric fluid at 37 degrees C) while under neutral conditions the swelling ratio of citrate/chitosan film was less significant and the release rate of brilliant blue and riboflavin was low (less than 40% released in simulated intestinal fluid in 24 h). Sodium chloride weakened the electrostatic interaction between citrate and chitosan, and therefore facilitated the film swelling and accelerated drug release. The parameters of film preparation such as citrate concentration, solution pH etc. influencing the film swelling and drug release profiles were examined. The lower concentration and the higher pH of citrate solution resulted in a larger swelling ratio and quicker riboflavin release. To improve the drug controlled release properties of citrate/chitosan film, heparin, pectin and alginate were further coated on the film surface. Among them only the coating of alginate prolonged riboflavin release noticeably (for 80% of drug released the time was extended from 1.5 to 3.5 h with 0.5% w/v alginate used). The results indicated that the citrate/chitosan film was useful in drug delivery such as for the site-specific drug controlled release in stomach. 相似文献
7.
Wound dressings based on chitosans and hyaluronic acid for the release of chlorhexidine diacetate in skin ulcer therapy 总被引:2,自引:0,他引:2
Rossi S Marciello M Sandri G Ferrari F Bonferoni MC Papetti A Caramella C Dacarro C Grisoli P 《Pharmaceutical development and technology》2007,12(4):415-422
In the present work wound dressings, based on chitosan hydrochloride (HCS), 5-methyl-pyrrolidinone chitosan (MPC), and their mixtures with an anionic polymer, hyaluronic acid (HA), were prepared by freeze-drying. Chlorhexidine diacetate (CX) was used as an antimicrobic drug. The mechanical properties of the wound dressings were investigated. In particular, the wound dressings were subjected to dynamic hydration measurements to evaluate their capability to absorb wound exudate and to rheological analysis to investigate their resistance to mechanical stresses on hydration. The wound dressings were also characterized for drug release properties. The antioxidant and antimicrobial activities of medicated and non-medicated wound dressings were also investigated. All the wound dressings are characterized by mechanical resistance suitable for skin application. The addition of hyaluronic acid to chitosans leads to a reduction in wound dressing hydration properties and a modulation of drug release. The wound dressing based on MPC is characterized by the highest elastic properties and by the best scavenger activity. Antimicrobial activity against bacteria and C. albicans is shown by the dressing based on chitosan also in absence of chlorhexidine. 相似文献
8.
9.
《Saudi Pharmaceutical Journal》2022,30(10):1507-1520
PurposeThis work aimed to develop and analyze the performance of chitosan/alginate polyelectrolyte complex (PEC). Multiple regression and Lab fit curve fitting were applied to derive empirical models for the prediction of zeta potential of plain systems as a function of alginate chitosan ratio. Venlafaxine-HCl was loaded as a model charged drug and empirical models for prediction of its release as a function of time were also derived.MethodsCoacervation method was used for the preparation of green PECs. Preliminary studies were conducted to optimize the preparation method. Pre-adjustment of the pH of alginate and chitosan sols enabled the formation of PECs at alginate/chitosan ratios starting from 1:9 to 9:1. On mixing of alginate and chitosan sols, equal volume dilution method produced spherical particles, while direct mixing method gave fibrous particles. Twenty-seven PECs nanoparticle formulae were prepared using nine alginate/chitosan ratios and three levels of total polymer concentrations.ResultsStatistical analysis showed that Zeta potential of the nanoparticle was significantly dependent on alginate/chitosan ratio, while particle size was a function of total polymer concentration. Nine fiber formulae were prepared and evaluated for their appearance and zeta potential. Venlafaxine-HCl release followed anomalous transport mechanism. FT-IR and DSC studies confirmed complexation at the carboxylate and amine site at alginate and chitosan respectively.ConclusionChitosan/alginate PECs were successfully obtained without a cross-linker and empirical equations were obtained to help finding the best composition for loading charged drugs and to predict their release profiles. 相似文献
10.
Lira AA Rossetti FC Nanclares DM Neto AF Bentley MV Marchetti JM 《Journal of microencapsulation》2009,26(3):243-250
Chitosan treated alginate microparticles were prepared with the purpose of incorporating all-trans retinoic acid (ATRA) using an inexpensive, simple and fast method, enhancing dermal localization and sustaining the release of ATRA into the skin. Microparticles characterization, drug-polymer interaction, release profile and in vitro skin retention were investigated. Microparticles presented spherical shape and drug loading capacity of 47%. The drug content of these microparticles was affected by ATRA concentration and by the solvent used and it was more weakly affected by chitosan concentration. The release of ATRA was also affected by chitosan concentration. Microparticles prepared with 0.4% chitosan (w/w) resulted in drug release with a more sustained profile. The results of in vitro retention studies showed that chitosan treated alginate microparticles decreased the drug retention in the stratum corneum (SC), where occur the skin irritation, but maintained the ATRA concentration in the deeper skin layers, where occur the pathologies treated with ATRA. Then, the microparticles developed in this work can be a good candidate to improve the topical therapy with retinoid. 相似文献