Publications by authors named "Safaa Gamal"

To address escalating environmental and sustainability concerns of petroleum-based superplasticizers (SPs), this work aims to develop sustainable and eco-friendly starch-based SPs using gamma radiation for maintaining the desired workability of geopolymeric pastes. Specifically, two green SPs were prepared from starch via radiation-induced grafting of two sulfonic group-bearing monomers, namely 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and 4-styrene sulfonic acid sodium salt (Na4SS). The grafting reaction was improved by initial modification of starch with glycidyl methacrylate to insert vinyl groups into the starch backbone.

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In this work, the effect of adding Magnesium Oxide (MgO) and Titanium Dioxide (TiO) nanoparticles to enhance the properties of the bone cement used for hip prosthesis fixation. Related to previous work on enhanced bone cement properties utilizing MgO and TiO, samples of composite bone cement were made using three different ratios (0.5%:1%, 1.

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Brimonidine ocular hypotensive effect can be enhanced by increasing residence time and corneal penetration. The current work aimed to formulate, evaluate and compare nanostructured lipid carriers (NLCs) to solid lipid nanoparticles (SLNs) and commercial eye drops for controlled brimonidine delivery. NLCs prepared by modified high shear homogenisation were spherical with a mean size of 151.

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Nanoparticulate delivery systems have recently been under consideration for topical ophthalmic drug delivery. Brimonidine base-loaded solid lipid nanoparticles and nanostructured lipid carrier formulations were prepared using glyceryl monostearate as solid lipid and were evaluated for their physical stability following sterilization by autoclaving at 121°C for 15min. The objective of this work was to evaluate the effect of autoclaving on the physical appearance, particle size, polydispersity index, zeta potential, entrapment efficiency and particle morphology of the prepared formulations, compared to non-autoclaved ones.

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In the current study, the influence of chitosan on the dissolution rate and bioavailability of acyclovir has been illustrated through the preparation of co-crystals by simple solvent change method. Chitosan was precipitated on acyclovir crystals using sodium citrate as the salting out agent. The pure drug and the prepared co-crystals using different concentrations and molecular weights of chitosan were characterized in terms of drug content, particle size, thermal behavior, IR analysis, surface morphology, in vitro drug release and physical stability.

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The purpose of this research was to prepare a floating drug delivery system of acyclovir. Floating matrix tablets of acyclovir were developed to prolong gastric residence time and increase its bioavailability. The tablets were prepared by direct compression technique, using polymers such as hydroxypropylmethylcellulose 4000, Compritol 888.

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Metronidazole was formulated in mucoadhesive vaginal tablets by directly compressing the natural cationic polymer chitosan, loosely cross-linked with glutaraldehyde, together with sodium alginate with or without microcrystalline cellulose (MCC). Sodium carboxymethylcellulose (CMC) was added to some of the formulations. The drug content in tablets was 20%.

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