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Papers by Elsayed Ibrahim

International Journal of Pharmaceutics

World Journal of Pharmacy and Pharmaceutical Sciences, 2017

Azathioprine is immunosuppressant drug used effectively for treatment of gastroduodenal Crohn’s d... more Azathioprine is immunosuppressant drug used effectively for treatment of gastroduodenal Crohn’s disease, jejunoileitis and ileitis. The systemic administration of azathioprine is characterized by its slow onset of action and causing serious adverse effects. The objective of the current work was to develop and evaluate azathioprine-loaded pectin beads for intestinal release of azathioprine (i.e. the inflammatory disease site) to overcome the characteristic drawbacks of the systemic administration of azathioprine. Two different preparation techniques were followed to develop azathioprine-loaded pectin beads by ionotropic gelation. Several characterizations were carried out for the developed beads (e.g. size, morphological features, yield, drug loading capacity, drug entrapment efficiency and in vitro release) to select the better preparation technique, and further optimization studies were performed. Azathioprine-loaded pectin beads were successfully developed as spherical beads of 1.62 ± 0.04 mm diameter and high entrapment efficiency (c.a. 94%). The in vitro release profiles of the developed azathioprine-loaded pectin beads showed that most of the drug amounts released at intestinal simulating medium. The azathioprine-loaded pectin beads developed in the current study might have a promising potential for treatment of gastroduodenal Crohn’s disease, jejunoileitis and ileitis effectively, more effectively and more safely than the systemic administration of azathioprine.

Bulletin of Pharmaceutical Sciences. Assiut, 1987

Journal of Drug Delivery Science and Technology, 2020

Quercetin, a natural flavonoid has high potential for management of inflammatory bowel diseases (... more Quercetin, a natural flavonoid has high potential for management of inflammatory bowel diseases (IBD). However, its onset of action is delayed when administered systemically and high doses are needed for IBD treatment. The present study aimed to develop chitosan microparticles for colonic delivery of clinically relevant quercetin concentrations as a potential treatment for IBD. Different formulations of quercetin microparticles were prepared and evaluated in terms of pharmaceutical, morphological and compatibility aspects. The in vitro release profiles of acid-resistant capsules filled with quercetin microparticles showed that most of quercetin was released in IBD colon simulating medium. Rabbit colitis model was used to evaluate the therapeutic effects of quercetin microparticles based on various assessment criteria (e.g. index of tissue edema, clinical activity score, colon macroscopic and histopathological characteristics, biochemical assays of the levels of myeloperoxidase enzyme and tumor necrosis factor-α and the activities of superoxide dismutase and catalase). The animals treated with quercetin microparticles had significantly improved therapeutic outcomes as compared to those treated with plain drug and the untreated animal controls. The results demonstrate that the developed quercetin microparticles have suitable pharmaceutical properties and might find clinical applications in acute IBD management.

European Journal of Pharmaceutical Sciences, 2017

Azathioprine is a highly efficient immunosuppressant drug used for treatment of inflammatory bowe... more Azathioprine is a highly efficient immunosuppressant drug used for treatment of inflammatory bowel disease (IBD). Systemic administration of azathioprine results in delayed therapeutic effect and serious adverse reactions. In the current study, we have developed, for the first time, colon-targeted chitosan beads for delivery of azathioprine in colitis rabbit model. Several characterizations were performed for the azathioprine-loaded beads (e.g. drug encapsulation efficiency, drug loading capacity, yield, size, shape and compatibility with other ingredients). The in vitro release profiles of acid-resistant capsules filled with azathioprine-loaded beads showed that most of azathioprine was released in IBD colon simulating medium. The therapeutic effects of azathioprine-loaded beads and azathioprine crude drug were examined on acetic acidinduced colitis rabbit model. Improved therapeutic outcomes were observed in the animals treated with the azathioprine-loaded beads, as compared to the untreated animal controls and the animals treated with the azathioprine free drug, based on the clinical activity score, index of tissue edema, mortality rate, colon macroscopic score and colon histopathological features. In the animals treated with the azathioprine-loaded beads, the levels of the inflammatory mediators, myeloperoxidase enzyme and tumor necrosis factor-α, were significantly reduced to levels similar to those observed in the normal rabbits. Furthermore, the activities of the antioxidant enzymes, superoxide dismutase and catalase, were restored considerably in the animals treated with the drug-loaded beads. The azathioprine-loaded beads developed in the current study might have great potential in the management of IBD.

journal of Pharmaceutical Technology and Drug Research, 2014

Background: Nonviral polymeric delivery systems are explored to enhance clinical development of n... more Background: Nonviral polymeric delivery systems are explored to enhance clinical development of nucleic acids as therapeutic entities for effective management of debilitating conditions such as cancer. This study was to compare safety and efficacy of quaternary amine-containing methacrylate polymer Eudragit ® RL PO (ERL) and poly[N-(2-hydroxypropyl)methacrylamide]-poly(N,N-dimethylaminoethyl methacrylate) copolymer (pHPMA-b-pDMAEMA), which contains secondary and tertiary amines, as effective gene carriers. Methods: Polyplexes of pAcGFP1-C1 with ERL or pHPMA-b-pDMAEMA were fabricated at different N/P ratios. Formation of DNA/catiomer nanostructures was monitored by ethidium bromide intercalation and agarose gel retardation. Particle size, zeta potential and cytotoxicity of different polyplexes were characterized. Transfection efficiency in presence and absence of serum was assessed using confocal microscopy. Results: pHPMA-b-pDMAEMA demonstrated at least a 10-fold greater DNA condensation capacity per weight unit than ERL. However, DNA intercalation with pHPMA-b-pDMAEMA was reduced in presence of serum-free cell culture media, whereas polyplex formation with ERL was equivalent in phosphate-buffered saline, pH 7.4 and serum-free cell culture media. Cellular safety of HeLa cells was not compromised by polyplexes fabricated with either polymer up to N/P=4. However, ERL alone was more toxic. In absence of serum, pHPMA-b-pDMAEMA polyplexes at N/P=4 induced equivalent transgene expression as control TurboFect™ polyplexes. In contrast, ERL-containing nanoassemblies failed to produce measurable transgene expression. Inclusion of serum significantly decreased transfection efficiency of pHPMA-b-pDMAEMA-containing polyplexes by ~30% at N/P=4 and ~50% at N/P=2. Conclusion: Polyplexes fabricated with secondary and tertiary amine-containing pHPMA-b-pDMAEMA copolymer represent more effective gene delivery systems than nanoassemblies composed of quaternary amine-containing ERL and should be further explored for clinical applications.

Journal of Obstetrics and Gynaecology Research, 2011

Aim: To compare the efficacy of a novel vaginal delivery system for metronidazole (0.8% MTZ in si... more Aim: To compare the efficacy of a novel vaginal delivery system for metronidazole (0.8% MTZ in situ gel) versus a conventional MTZ vaginal gel product in the treatment of bacterial vaginosis (BV). Material and Methods: All consecutive patients who presented to a tertiary care hospital with symptoms suggestive of BV were approached to participate in the study. Forty-two eligible participants were randomly assigned to either MTZ in situ gel or a conventional vaginal gel product twice daily for 5 days. All participants were reexamined after one and 4 weeks of the beginning of treatment to ensure cure of infection and any side-effects. Results: Demographic criteria of the participants were comparable in the two treatment groups. The cure rate after one week from the treatment was 85% in the in situ gel group and 71.4% in the conventional vaginal gel group (P = 0.294), while after 4 weeks, the cure rate showed significant difference in the in situ gel group as compared to the conventional vaginal gel group (16/20 [80%]) and (9/19 [47.4%]), respectively (P = 0.034). Conclusion: Pilot testing showed that in situ MTZ vaginal gel is more effective than the conventional vaginal gel for long-term cure of BV. These findings suggest a novel and efficient long-term treatment of BV.

Acta Pharmaceutica, 2012

Development and characterization of thermosensitive pluronic-based metronidazolein situgelling fo... more Development and characterization of thermosensitive pluronic-based metronidazolein situgelling formulations for vaginal applicationThe purpose of this study was to develop pluronic-basedin situgelling formulations of metronidazole (MTZ) for treatment of bacterial vaginosis, aimed at prolonging the residence time, controlling drug release, enhancing efficacy, decreasing recurrence, and increasing patient compliance. Thein situgel formulations were prepared using different concentrations of pluronic F-127 (PF-127) alone and in combination with pluronic F-68 (PF-68). The prepared formulations were evaluated for their gelation temperature (Tgel),in vitrodrug release, rheological properties, mucoadhesion properties and tolerability by vaginal mucosa in tissue levels. TheTgeldecreased with increasing PF-127 concentration. TheTgelwas modulated by addition of PF-68 to be within the acceptable range of 25-37 °C. With increasing pluronic concentration, thein vitrodrug release decreased, visco...

International Journal of Pharmacy and Pharmaceutical Sciences, 2020

Objective: This study was undertaken to determine the bioavailability of ondansetron gel in exper... more Objective: This study was undertaken to determine the bioavailability of ondansetron gel in experimental animals and humans applying UPLC as an analytical tool and evaluation of the antiemetic effect of ondansetron gel in cisplatin-induced emesis in rats. Methods: Ondansetron gel (F13: sodium alginate 7% w/w) was used, marketed I. V. ondansetron (Zofran) ® was chosen as reference. The bioavailability study in rabbits was selected as a parallel design using nine healthy rabbits divided into three groups whereas, bioavailability study in humans was an open-label, wherein 6 healthy subjects administered ondansetron gel. The potential effect of ondansetron gel was evaluated for the prevention of different phases of emesis motivated by exposure to antineoplastic drugs (cisplatin) by determination of body weight loss, water and food intake applying kaolin-pica model in rats using seventy-two rats divided into six groups. Results: Ondansetron gel (0.5%) showed detectable plasma concentrati...

Bulletin of Pharmaceutical Sciences. Assiut, 2017

The aim of this study was to develop and evaluate ondansetron gels for transdermal effect using i... more The aim of this study was to develop and evaluate ondansetron gels for transdermal effect using in-vitro and ex-vivo permeation methods. Ondansetron gels were prepared using; sodium carboxymethyl cellulose (Na CMC), hydroxypropylmethyl cellulose (HPMC), hydroxypropyl cellulose (HPC), sodium alginate, and pluronic F-127 as gelling polymers. Polyvinyl pyrrolidone (PVP) and polyethylene glycol (PEG) 400 were used as solubility enhancers. Oleic acid, ethyl alcohol, menthol, isopropyl myristate and propylene glycol were evaluated as penetration enhancers. The effect of the employed gel bases and permeation enhancers on the physicochemical characterization and drug permeation through cellophane membrane and rat skin were determined. The results showed that both polymers and their concentrations affect the permeation of drug, by increasing the polymer concentration in the formulation, viscosity increased and invitro permeation of ondansetron decreased. Formula containing 16% of hydroxyl propyl cellulose with PVP/PEG400 (1.5/5% w/w) showed the highest amount permeation (95% over a 6 hrs period) through cellophane membrane. Both formulae containing 16% of hydroxyl propyl cellulose with PVP/PEG400 (1.5/5% w/w) and 7% of sodium alginate with PVP/ PEG400 (1.5/5% w/w) showed the best permeation through rat skin (amount permeated about 345.06 µg/cm 2) over a 6-hr period. PVP/PEG400 (1.5/5% w/w) showed the optimum solubilization enhancement.