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Ahmed, M. A., A. M. Al-mahallawi, S. N. El-helaly, and W. H. Abd-Elsalam, The effect of the saturation degree of phospholipid on the formation of a novel self-assembled nano-micellar complex carrier with enhanced intestinal permeability, , vol. 569, pp. 118567, 2019. AbstractWebsite

The aim of this research was to formulate a novel nano-micellar complex carrier with intrinsically enhanced intestinal permeability for rosuvastatin calcium (RSV); as a model of BCS class III active pharmaceutical ingredients (APIs). The model drug is used primarily for treating hypercholesterolemia. Three phospholipid types with different degrees of saturation were chosen for the study. The saturation degree of the phospholipids was calculated accurately by proton NMR. A D-optimal statistical design was utilized to correlate the saturation degree of the phospholipids with the physico-chemical characteristics of the prepared nano-micellar carrier. The nature of the interaction between the phospholipids and the model drug was studied by proton NMR, photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM). Molecular docking and molecular dynamics simulations were performed to understand the formation mechanism of the complex micelles on a molecular level. The results demonstrated that the interaction of the hydrophilic drug molecule with the polar head of a saturated phospholipid induces an intramolecular self-coiling of phospholipid saturated acyl chain leading to a structural transformation from a two-tailed cylindrical configuration into a one-tailed, surfactant-like configuration owing to the flexibility of the saturated chains. This transformation leads to the construction of a novel nano-micellar structure in which the drug has lower water solubility but higher lipophilicity than in traditional micelles. Permeability studies conducted on Caco-2 cells demonstrated that the novel nano-micellar carrier had superior permeability to that of the un-complexed hydrophilic drug. The optimized nano-micellar formulation showed significantly (P < 0.5) superior bioavailability in rats to that of the aqueous drug solution in terms of both the rate and extent of drug absorption. Overall, the results confirmed that the formation of the phospholipid nano-micellar complex increased the permeability of the hydrophilic BCS class III drug and converted it to a class BCS I drug by a simple and effective formulation technique.

Ali, M., A. A. Motaal, M. A. Ahmed, A. Alsayari, and O. N. El-Gazayerly, "An in vivo study of Hypericum perforatum in a niosomal topical drug delivery system", Drug Delivery, vol. 25, no. 1: Taylor & Francis, pp. 417-425, 2018. AbstractWebsite

AbstractThe active compounds present in Hypericum perforatum L. (Hypericaceae) include hyperforin, hypericins and flavonoids, which are assumed to be responsible for the activity of the extract in the treatment of wounds and scars. The present study aimed to incorporate H. perforatum extract standardized to a known content of phloroglucinols, naphthodianthrones and polyphenolic compounds into an effective transdermal drug delivery system capable of entrapping both lipophilic and hydrophilic constituents in the form of niosomal gels for wound treatment. An 80% ethanol extract (HE) was prepared on a pilot scale using DIG-MAZ. An HPLC-DAD holistic profile was established for HE and was standardized to contain 3.4 ± 4 rutin, 1.1 ± 3 chlorogenic acid, 0.5 ± 2 quercitrin, 2.8 ± 2 hyperforin, and 0.51 ± 3% w/w total hypericins. Niosomes were prepared using the modified reverse phase evaporation technique (REV). The wound healing effect of the gel was tested on 16 adult mongrel dogs. A significant decrease in the inflammatory cell count (18.4 ± 5.3) was recorded in the niosomal gel 1.5% NaCMC-treated group at the 7th day post wounding. It induced a marked regression in the inflammatory phase and enhanced the early beginning of the proliferative phase of wound healing. After 21 days, it showed complete re-epithelization, formation of new matrix fibers and significant reduction in the wound size, compared to the control and the Panthenol® 2% cream treated groups. This is the first study of H. perforatum in a niosomal topical drug delivery system.

Elmowafy, M., H. M. Ibrahim, M. A. Ahmed, K. Shalaby, A. Salama, and H. Hefesha, "Atorvastatin-loaded nanostructured lipid carriers (NLCs): strategy to overcome oral delivery drawbacks", Drug Delivery, vol. 24, no. 1: Taylor & Francis, pp. 932-941, 2017. AbstractWebsite

AbstractAtorvastatin (AT) is a widely used lipid-regulating drug to reduce cholesterol and triglycerides. Its poor aqueous solubility and hepatic metabolism require development of drug delivery systems able to improve its solubility and bypass hepatic effect. For this purpose, atorvastatin nanostructured lipid carriers (AT-NLCs) were prepared and characterized. AT-NLCs were prepared by emulsification using high-speed homogenization followed by ultrasonication. The prepared NLCs showed particle size between 162.5 ± 12 and 865.55 ± 28 nm while zeta potential values varied between −34 ± 0.29 and −23 ± 0.36 mV. They also showed high encapsulation efficiency (>87%) and amorphous state of the drug in lipid matrix. Pharmacokinetic parameters of optimized formulation (NLC-1; composed of 2% Gelucire® 43/01, 8% Capryol® PGMC, 2% Pluronic®F68 and 0.5% lecithin) revealed 3.6- and 2.1-fold increase in bioavailability as compared to atorvastatin suspension and commercial product (Lipitor®), respectively. Administration of NLC-1 led to significant reduction (p < .05) in the rats’ serum levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) and significant increase in high-density lipoprotein (HDL). This improvement was confirmed histologically by minimizing the associated hepatic steatosis. These investigations demonstrated the superiority of NLCs for improvement of oral bioavailability and in vivo performance of AT.

Morsi, N. M., G. A. Abdelbary, A. H. Elshafeey, and A. M. Ahmed, "Engineering of a novel optimized platform for sublingual delivery with novel characterization tools: in vitro evaluation and in vivo pharmacokinetics study in human", Drug Delivery, vol. 24, no. 1: Taylor & Francis, pp. 918-931, 2017. AbstractWebsite

AbstractThe aim of this work was to develop a novel and more efficient platform for sublingual drug delivery using mosapride citrate (MSP) as a model drug. The engineering of this delivery system had two stages, the first stage was tuning of MSP physicochemical properties by complexation with pure phosphatidylcholine or phosphatidylinositol enriched soybean lecithin to form MSP-phospholipid complex (MSP-PLCP). Changes in physicochemical properties were assessed and the optimum MSP-PLCP formula was then used for formulation into a flushing resistant platform using two mucoadhesive polymers; sodium alginates and sodium carboxymethylcellulose at different concentrations. Design of experiment approach was used to characterize and optimize the formulated flushing resistant platform. The optimized formulation was then used in a comparative pharmacokinetics study with the market formulation in human volunteers. Results showed a marked change in MSP physicochemical properties of MSP-PLCP compared to MSP. Addition of mucoadhesive polymers to flushing resistant platform at an optimum concentration balanced between desired mucoadhesive properties and a reasonable drug release rate. The optimized formulation showed significantly a superior bioavailability in humans when compared to the market sublingual product. Finally, the novel developed sublingual flushing resistant platform offers a very promising and efficient tool to extend the use of sublingual route and widen its applications.

Basalious, E. B., and A. M. Ahmed, "Phospholipid based self-nanoemulsifying self-nanosuspension (p-SNESNS) as a dual solubilization approach for development of formulation with diminished food effect: Fast/fed in vivo pharmacokinetics study in human", European Journal of Pharmaceutical Sciences, vol. 109, pp. 244 - 252, 2017. AbstractWebsite

The novel self- nanoemulsifying self-nanosuspension (SNESNS) combines the advantages of two efficient solubilization technologies; the nanoemulsion and the nanosuspension. The aim of this study is to test the efficiency of phospholipid based self-nanoemulsifying self-nanosuspension (p-SNESNS) formulation as a powerful tool to diminish the food effect on bioavailability of lurasidone hydrochloride as BCS Class II model drug. Phospholipid was incorporated into SNESNS to increase the solubilization power of the in-situ formed nanoemulsion and facilitate the dispersion of the in-situ formed nanosized drug particles. P-SNESNS was evaluated for particle size, Polydispersity index, in vitro dissolution and transmission electron microscopy (TEM). The drug amount dissolved after water dilution of LSD p-SNESNS was  2 folds that dissolved after dilution of non-phospholipid SNESNS. The self-nanosuspension obtained by aqueous dilution of p-SNESNS kept the cubic morphology of LSD macroparticles. The high in vitro dissolution of LSD in the non-sink dissolution media (water and Phosphate buffer pH6.8) indicated that the p-SNESNS formulation had successfully increased the drug solubility irrespective of pH of the medium. The pharmacokinetics parameters of LSD p-SNESNS in humans were the same in both the fasted and fed states and were similar to those of LSD capsules in the fed state. Our results propose that p-SNESNS could be promising to increase patient compliance and drug efficiency of BCS class II antipsychotics by diminishing the food effect on their oral absorption and preventing the necessity to administer them with food.