The influence of the use of viscosifying agents as dispersion media on the drug release properties from PLGA nanoparticles

Dillen, Kathleen; Weyenberg, Wim; Vandervoort, Jo; Ludwig, Annick

doi:10.1016/j.ejpb.2004.03.035

Cited by 36 publications

(17 citation statements)

References 29 publications

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“…Also, at all frequency values a liquid-like behavior is observed, so the viscous properties are more pronounced than the elastic ones (22). Similar liquid type behavior has been reported for chitosan gels in the literature (22)(23)(24).…”

Section: Results Of Rheological Studiessupporting

confidence: 84%

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

et al. 2014

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Vaginal yeast infections are among the most common reasons for women seeking medical care; it has been estimated that 70-75 % of women have an episode of Candida vaginitis at least once during their lifetime (1). Local administration of antimicrobial agents has been favored in the treatment of vaginitis because of the numerous side effects of systemically applied drugs. Vaginal dosage forms used for this purpose include solutions, gels, creams, ointments, foams, pessaries, tablets and vaginal inserts (1). To achieve a desirable therapeutic effect, vaginal delivery systems need to have the ability to spread onto the vaginal mucosa surface and guarantee an intimate and prolonged contact at the site of application (2). Therefore, localized mucoadhesive dosage forms The aim of the present study was to evaluate chitosan as a vaginal mucoadhesive gel base for econazole nitrate and miconazole nitrate. To this aim, different types of chitosan with different molecular masses and viscosity properties [low molecular mass chitosan (viscosity: 20,000 mPa s), medium molecular mass chitosan (viscosity: 200,000 mPa s), high molecular mass chitosan (viscosity: 800,000 mPa s)] have been used. First, rheological studies were conducted on chitosan gels. Mechanical, syringeability and mucoadhesive properties of chitosan gels were determined. Release profiles of econazole nitrate and miconazole nitrate from chitosan gels were obtained and evaluated kinetically. In addition, anticandidal activities of formulations were determined. Finally, vaginal retention of chitosan gels in rats was evaluated by in vivo distribution studies. Based on the results, it can be concluded that gels prepared with medium molecular mass chitosan might be effectively used for different antifungal agents in the treatment of vaginal candidiosis, since it has high mucoadhesiveness, suitable mechanical and release properties with good vaginal retention.

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Section: Results Of Rheological Studiessupporting

confidence: 84%

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

et al. 2014

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“…Despite these advances, these biodegradable nanostructured systems present a greater potential for the premature release of their contents into the bloodstream or during their preparation process, due to the fact that the encapsulated material is in thermodynamic equilibrium with the aqueous medium in which it is dispersed. Thus, the demand for stability will lead the system to release the encapsulated content until a new thermodynamic equilibrium can be reached [4][5][6]. In some cases, as medicines are used in cancer treatments or nanostructures carrying radioisotopes, it is crucial that the adequate concentrations reach the tumor tissue, thus requiring that the carrier not degrade or release its contents until it reaches its final destination, in turn ensuring high concentrations of the drug in the target cells [7].…”

Section: Introductionmentioning

confidence: 99%

Mesoporous silica SBA-16 nanoparticles: Synthesis, physicochemical characterization, release profile, and in vitro cytocompatibility studies

Andrade

Soares

Santos

et al. 2013

Microporous and Mesoporous Materials

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“…4,5 Moreover, NSs have the advantage of offering a sustained release of the drug entrapped in the polymeric matrix, so that the required tear levels and therapeutic effects can be achieved. 6 Although a different number of polymers have been investigated for formulating biodegradable NSs, aliphatic polyesters such as poly(D-lactic acid) (PLA) and its copolymers with glycolic acid (PLGA) have been extensively used for controlled drug-delivery systems due to many favorable characteristics such as good biocompatibility, their ability to degrade into natural metabolites, and their safety profile for human use. 7 Surface modification of PLGA NSs with polyethylene glycol (PEG) or PEGylation can modulate the interfacial properties of the system, and thus influence mucoadhesion to prolong the residence time of the particles in the precorneal area.…”

Section: Introductionmentioning

confidence: 99%

Role of hydroxypropyl-β-cyclodextrin on freeze-dried and gamma-irradiated PLGA and PLGA–PEG diblock copolymer nanospheres for ophthalmic flurbiprofen delivery

Vega¹,

Egea²,

Calpena³

et al. 2012

IJN

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Poly(D,L-lactide-co-glycolide) and poly(D,L-lactide-co-glycolide) with poly(ethylene glycol) nanospheres (NSs) incorporating flurbiprofen (FB) were freeze-dried with several cryoprotective agents and sterilized by γ-irradiation. Only when 5.0% (w/v) hydroxypropyl-β-cyclodextrin (HPβCD) was used, a complete resuspension by manual shaking and almost identical particle size of the NSs was obtained after freeze-drying. In vitro drug release and ex vivo corneal permeation of NSs with and without HPβCD were evaluated. The presence of HPβCD resulted in a reduction of burst effect, providing a more sustained release of the drug. A significant decrease in the FB transcorneal permeation of NSs containing HPβCD was obtained, related to the slower diffusion of FB observed in the in vitro results. The uptake mechanism of the NSs was examined by confocal microscopy, suggesting that NSs penetrate corneal epithelium through a transcellular pathway. Ocular tolerance was assessed in vitro and in vivo by the Eytex™ and Draize test, respectively. Long-term stability studies revealed that γ-irradiated NSs stored as freeze-dried powders maintained their initial characteristics. Stability studies of the resuspended NSs after 3 months of storage in the aqueous form showed that NSs were stable at 4°C, while formulations stored at 25°C and 40°C increased their initial particle size.

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The influence of the use of viscosifying agents as dispersion media on the drug release properties from PLGA nanoparticles

Cited by 36 publications

References 29 publications

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Mesoporous silica SBA-16 nanoparticles: Synthesis, physicochemical characterization, release profile, and in vitro cytocompatibility studies

Role of hydroxypropyl-β-cyclodextrin on freeze-dried and gamma-irradiated PLGA and PLGA–PEG diblock copolymer nanospheres for ophthalmic flurbiprofen delivery

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The influence of the use of viscosifying agents as dispersion media on the drug release properties from PLGA nanoparticles

Cited by 36 publications

References 29 publications

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Mesoporous silica SBA-16 nanoparticles: Synthesis, physicochemical characterization, release profile, and in vitro cytocompatibility studies

Role of hydroxypropyl-&beta;-cyclodextrin on freeze-dried and gamma-irradiated PLGA and PLGA&ndash;PEG diblock copolymer nanospheres for ophthalmic flurbiprofen delivery

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Role of hydroxypropyl-β-cyclodextrin on freeze-dried and gamma-irradiated PLGA and PLGA–PEG diblock copolymer nanospheres for ophthalmic flurbiprofen delivery