Rheological study of a thermoreversible morphine gel

Dumortier, G.; Grossiord, J. L.; Zuber, Mathieu; Couarraze, G.; Chaumeil, Jean‐Claude

doi:10.3109/03639049109043858

Cited by 58 publications

(45 citation statements)

References 14 publications

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“…As can be seen, these chitosan gels are characterized by lower G' and higher G" values, pointing to a mainly viscous polymer solution containing a network established by physical entanglements. 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: 66%

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: 66%

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

et al. 2014

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“…48 By using oscillatory rheology, it is possible to quantify both the elastic-like and viscous-like properties of formulations; it is thus a valuable tool for understanding the structural and dynamical properties of these systems. In oscillatory rheometry, the effects of oscillatory stresses on the viscoelastic properties are measured and two dynamic moduli are obtained: 1) the storage modulus (G′, a measure of the elasticity); and 2) the loss modulus (G″, representing viscous components at given frequency).…”

Section: Rheological Properties Of Formulationsmentioning

confidence: 99%

Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

Şenyiğit¹,

Karavana²,

İlem-Özdemir³

et al. 2015

IJN

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This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan–thioglycolic acid conjugate) and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosanthioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in situ gelling properties at body temperature, which is in conflict with the aimed formulation property. Therefore, 2% chitosan gel formulation was found to be a more promising carrier system for intravesical administration of nanoparticles.

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“…In our study, we measured the gelation temperature of the desensitizing gels with different concentrations of P407. Different from previous researches (Dumortier G et al, 1991;Lenarets V et al, 1987), the desensitizing gel existed as gel at low temperature but turned to liquid when the temperature increasing. Mechanism of the phenomenon needed further research.…”

Section: Discussionmentioning

confidence: 92%

“…Poloxamer, a copolymer of poly (oxyethylene)-poly (oxypropylene)-poly (oxyethylene), was employed as themosensitive material for the desensitizing gel. Poloxamer solutions exhibit a thermosensitive gelling property, which means they are solutions at low temperatures but turn to gels when the temperature increasing, especially P407 (Dumortier G et al, 1991;Lenarets V et al, 1987). P407 is commonly utilized in liquid suppository not only due to the thermosensitive gelling property, but also due to low toxicity, excellent water-solubility, good drug release characteristics and compatibility with other chemicals.…”

Section: Discussionmentioning

confidence: 99%

Effects of a traditional chinese medicine based desensitizing gel on dentin hypersensitivity.

Wang¹,

Zhao²,

Ji³

2015

Afr. J. Trad. Compl. Alt. Med.

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Background and Objective: Bamboo salt, Calcined oyster, Drynaria fortunei, Indigo naturalis and Rehmannia glutinosa have been the main ingredients of many formulations in Chinese medicine for the treatment of toothache. This study evaluated the effect of a new desensitizing gel on dentin hypersensitivity (DH). Materials and Methods: The desensitizing gel was prepared through a confirmed prescription of ingredients mentioned above and Poloxamer 407 (P407). The best concentration of P407 in prescription was screened according to the gelatin temperature of gel. Scanning electron microscopy (SEM) was used to evaluate the dentinal tubule occlusion of 32 human premolars under various treatments including the desensitizing gel. Randomized controlled clinical trials were conducted to evaluate the clinical effect of the desensitizing gel. Results:The best concentration of P407 in prescription was 0.30g/ml. Scanning electron micrographs of the cross-sectional and longitudinal dentin surfaces revealed most of the dentinal tubules were occluded by sedimentation after desensitizing gel treatment, and significant difference existed compared to the control groups. Randomized clinical trials showed 173.72% and 270.07% mean relative improvements on tactile hypersensitivity at one-month and two-month follow-ups, and 54.11% and 90.91% mean relative reductions on air blast hypersensitivity at one-month and two-month follow-ups (p<0.05). There was no statistical difference between the desensitizing gel and Duraphat group at different time intervals (p>0.05). Conclusions: Based on these findings, the desensitizing gel exhibits an obvious effect on dentinal tubule occlusion. Besides, data of the randomized clinical trials indicate a potential role for the desensitizing gel in managing DH.

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Rheological study of a thermoreversible morphine gel

Cited by 58 publications

References 14 publications

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

Effects of a traditional chinese medicine based desensitizing gel on dentin hypersensitivity.

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Rheological study of a thermoreversible morphine gel

Cited by 58 publications

References 14 publications

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Evaluation of chitosan based vaginal bioadhesive gel formulations for antifungal drugs

Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan&ndash;thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

Effects of a traditional chinese medicine based desensitizing gel on dentin hypersensitivity.

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Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers