Heba F. Salem

In vitro/in vivo correlation and modeling of emitted dose and lung deposition of inhaled salbutamol from metered dose inhalers with different types of spacers in noninvasively ventilated patients

Abstract Substituting spacer by another in noninvasive ventilation (NIV) involves many variables, e.g. total emitted dose (TED), mass median aerodynamic diameter (MMAD), type of spacer, total lung deposition and total systemic absorption, which must be adjusted to ensure patient optimum therapy. Data mining based on artificial neural networks and genetic algorithms were used to model in vitro inhalation process, predict and optimize bioavailability from inhaled doses delivered by metered dose inhaler (MDI) using different spacers in NIV. Modeling of data indicated that in vitro performance of MDI-spacer systems was dependent mainly on fine particle dose (FPD), fine particle fraction (FPF), MMAD and to lesser extent on spacer type. Ex vivo model indicated that amount of salbutamol collected on facemask filter was directly affected by FPF. In vivo model (24hQ) depended directly on spacer type, FPF and TED. Female patients showed higher 0.5hQ and 24hQ values than males. AeroChamber VC spacer demonstrated higher TED and 24hQ in vivo values. Results indicated suitability of MDI-spacer systems in achieving appropriate in vitro inhalation performance. The possibility of modeling and predicting both ex vivo and in vivo capabilities of MDI-spacer systems from knowledge of in vitro attributes enabled detailed focus on important variables required to deliver safe and accurate doses of salbutamol to ventilated patients.

5-Fluorouracil shell-enriched solid lipid nanoparticles (SLN) for effective skin carcinoma treatment

Abstract Context: The effective treatment of skin carcinoma is warranted for targeting the chemotherapeutic agents into tumor cells and avoiding unwanted systemic absorption. Objective: This work was dedicated to the purpose of engineering highly penetrating shell-enriched nanoparticles that were loaded with a hydrophilic chemotherapeutic agent, 5-fluorouracil (5-FU). Methods: Varying ratios of lecithin and poloxamer188 were used to produce shell-enriched nanoparticles by enabling the formation of reversed micelles within this region of the SLN. The localization of 5-FU within the shell region of the SLN, was confirmed using 5-FU nanogold particles as a tracer. SLN were introduced within sodium carboxy methylcellulose hydrogel, and then applied onto the skin of mice-bearing Ehrlich’s ascites carcinoma. The mice were treated with the gel twice daily for 6 weeks. Results: The transmission electron microscope (TEM) revealed the formation of uniform nanoparticles, which captured reversed micelles within their shell region. The SLNs’ had particle size that ranged from 137 ± 5.5 nm to 800 ± 53.6, zeta potential of −19.70 ± 0.40 mV and entrapment efficiency of 47.92 ± 2.34%. The diffusion of the drug-loaded SLN (269.37 ± 10.92 μg/cm2) was doubled when compared with the free drug (122 ± 3.09 μg/cm2) when both diffused through a hydrophobic membrane. SLN-treated mice exhibited reduced inflammatory reactions, with reduced degrees of keratosis, in addition to reduced symptoms of angiogenesis compared to 5-FU-treated mice. Conclusion: SLN possesses the capacity to be manipulated to entrap and release hydrophilic antitumor drugs with ease.

In vitro/in vivo evaluation of an optimized fast dissolving oral film containing olanzapine co-amorphous dispersion with selected carboxylic acids.

Abstract Improvement of water solubility, dissolution rate, oral bioavailability, and reduction of first pass metabolism of OL (OL), were the aims of this research. Co-amorphization of OL carboxylic acid dispersions at various molar ratios was carried out using rapid solvent evaporation. Characterization of the dispersions was performed using differential scanning calorimetry (DSC), Fourier transform infrared spectrometry (FTIR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM). Dispersions with highest equilibrium solubility were formulated as fast dissolving oral films. Modeling and optimization of film formation were undertaken using artificial neural networks (ANNs). The results indicated co-amorphization of OL-ascorbic acid through H-bonding. The co-amorphous dispersions at 1:2 molar ratio showed more than 600-fold increase in solubility of OL. The model optimized fast dissolving film prepared from the dispersion was physically and chemically stable, demonstrated short disintegration time (8.5 s), fast dissolution (97% in 10 min) and optimum tensile strength (4.9 N/cm2). The results of in vivo data indicated high bioavailability (144 ng h/mL) and maximum plasma concentration (14.2 ng/mL) compared with the marketed references. Therefore, the optimized co-amorphous OL-ascorbic acid fast dissolving film could be a valuable solution for enhancing the physicochemical and pharmacokinetic properties of OL.

An Additional risk of Lung Cancer from Recurrent Exposure to EthylCarbamate (EC) in BALB/C Mice

Ethyl carbamate (EC); urethane is a chemical carcinogen (IARC group 2A). It has been commonly found in the fermented food and beverages. EC induced cancerous lesion in different sites due to the formation of active metabolite; vinyl carbamate (VC). The current study aims to investigate the potential risk of cancerous lesions in small and repeated exposure of ethyl carbamate in BALB/C mice. Three groups of BALBL/C mice were treated for 120 days included untreated control; group treated with a single dose of urethane (1.5 g/kg B.w/i.p) at a day one; group treated with repeated doses, the first at a day one and a second at day sixty (1.5g/ kg B.w/i.p). Ethyl carbamate (EC) exposure showed sever changes of serum biochemical markers, apoptosis markers, inflammatory cytokines as well as lipid peroxide formation in lung homogenate, these changes were pronounced in repeated exposure to ethyl carbamate. In addition, histological examinations revealed that epithelial changes in pulmonary tissues were advanced in animals treated with repeated doses of ethyl carbamate. These findings indicate that repeated exposure to ethyl carbamate of fermented foods and beverages is an additional risk for lung cancer due to permanent mitochondrial dysfunction and increase the cellular mitotic activity.

Nanotransfersomes-loaded thermosensitive in situ gel as a rectal delivery system of tizanidine HCl: preparation, in vitro and in vivo performance

Abstract The purpose of the current study was to develop tizanidine HCl (TIZ; a myotonolytic agent used for treatment of spasticity) loaded nanotransfersomes intended for rectal administration, aiming to bypass the hepatic first-pass metabolism. TIZ-loaded nanotransfersomes were prepared by thin-film hydration method followed by characterization for various parameters including entrapment efficiency, vesicle diameter, in vitro release and ex vivo permeation studies. Transfersomal formulation composed of phosphatidylcholine and Tween 80 at a weight ratio of (85:15) gave a satisfactory results. It exhibited encapsulation efficiency of 52.39%, mean diameter of 150.33 nm, controlled drug release over 8 h and good permeation characteristics. Optimum formula was then incorporated into Pluronic-based thermoreversible gel using hydroxypropyl methylcellulose (HPMC) as a mucoadhesive polymer. Pharmacokinetic study was performed by rectal administration of transfersomes-loaded in situ gel to rabbits and compared with oral drug solution and rectal TIZ in situ gel. The pharmacokinetic study revealed that the transfersomal formulation successively enhanced the bioavailability of TIZ by about 2.18-fold and increased t1/2 to about 10 h as compared to oral solution. It can be concluded that encapsulation of TIZ into nanotransfersomes can achieve a dual purpose of prolonged TIZ release and enhanced bioavailability and so may be considered as a promising drug delivery system for the treatment of spasticity.

Antitumor activity of intratracheal inhalation of temozolomide (TMZ) loaded into gold nanoparticles and/or liposomes against urethane-induced lung cancer in BALB/c mice

Abstract The current study aimed to develop gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) as drug carriers for temozolomide (TMZ) and investigate the possible therapeutic effects of intratracheal inhalation of nanoformulation of TMZ-loaded gold nanoparticles (TGNPs) and liposome-embedded TGNPs (LTGNPs) against urethane-induced lung cancer in BALB/c mice. Physicochemical characters and zeta potential studies for gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) were performed. The current study was conducted by inducing lung cancer chemically via repeated exposure to urethane in BALB/C mice. GNPs and LGNPs were exhibited in uniform spherical shape with adequate dispersion stability. GNPs and LGNPs showed no significant changes in comparison to control group with high safety profile, while TGNPs and LTGNPs succeed to improve all biochemical data and histological patterns. GNPs and LGNPs are promising drug carriers and succeeded in the delivery of small and efficient dose of temozolomide in treatment lung cancer. Antitumor activity was pronounced in animal-treated LTGNPs, these effects may be due to synergistic effects resulted from combination of temozolomide and gold nanoparticles and liposomes that may improve the drug distribution and penetration.

Edge activators and a polycationic polymer enhance the formulation of porous voriconazole nanoagglomerate for the use as a dry powder inhaler.

Abstract Purpose: Voriconazole has both low aqueous solubility and stability. We hypothesize that designing voriconazole in the form of a nano powder inhaler at a geometric diameter within 1–5 μm will enhance its stability and solubility. Therefore, we prepared nanoagglomerates of voriconazole which will collapse in the lungs to reform the nanoparticles. Method: The nanoparticles were formulated using both stearic acid and sodium deoxycholate as edge activators. Osmogenic polycation polyethyleneimine (PEI) was used to form agglomerates of controllable size. Results: Voriconazole nanoparticles and agglomerates showed a significant higher cumulative drug release than the pure powder (p < 0.05) with R2 = 0.95. Small-sized particles were formed (353 nm), while their zeta potential was −30.7 mV. The agglomerates were 2.7 μm in size and their zeta potential was −20.9 mV. The formation of porous agglomerates was confirmed using a transmission electron microscope. Cascade impactor was used to evaluate the aerodynamic properties of the nanoparticles and the agglomerates. The aerodynamic characterization of the nanoparticles and the agglomerates resulted in a significant smaller mass median aerodynamic diameter (MMAD) (p < 0.05) and higher fine particle dose (FPD) (p < 0.01), fine particle fraction (FPF) (p < 0.01), and total emitted dose (TED) (p < 0.01) than the pure powder. Conclusion: The results suggest that using the combination of edge activators and diluted polycationic polymer solution provides porous voriconazole nanoagglomerates in a respirable range, which is proved successful in enhancing both the deposition and the dissolution of water insoluble-drugs in the lung.

Formulation Development of Self-Nanoemulsifying Drug Delivery System of Celecoxib for the Management of Oral Cavity Inflammation

Abstract The oral administration of celecoxib (CLX) is a real problem because of its low aqueous solubility that results in high variability in absorption and its severe adverse effect such as cardiotoxic effects and gastrointestinal toxicity. Self-nanoemulsifying drug delivery systems (SNEDDS) can enhance the poor dissolution and erratic absorption of poorly water-soluble drugs such as CLX. This study was conducted to investigate the potential of SNEDDS to enhance the efficacy of CLX on inflamed mucous tissue and reduce systemic adverse effects by increasing its poor dissolution properties. A pseudo-ternary phase diagram was derived from the results of CLX solubility experiments in various excipients. These studies revealed the use of Labrafil M 2515 CS as oil, tween 80 as a surfactant, and polyethylene glycol 400 as a co-surfactant for the optimization of SNEDDS formulations. Eight formulations were formulated and characterized by their particle size, polydispersity index, viscosity, globular shape, drug solubility, self-emulsification efficiency, in vitro drug release, and permeation. The anti-inflammatory effect of CLX-SNEDDS was evaluated by carrageenan-induced cheek oedema in rats. The cheeks were treated with CLX-SNEDDS before oedema induction and then noticed for narrow periods (2 h) followed by histopathological studies to determine the efficacy of treatment. The selected formulations (F3 and F5) showed spherical morphologies under transmission electron microscopy, mean droplet sizes of 116.9 ± 1.78 and 124 ± 1.87 nm, respectively, complete in vitro drug release, and high cumulative amounts of drug permeation in 8 h. They also showed significant remarkable cheek oedema inhibition in comparison with the control groups (p < 0.05). CLX-SNEDDS was found to achieve effective local therapeutic concentration and intended to reduce cheek oedema, congestive capillary, inflammatory cells, and side effects due to lower dose size.

Progesterone-loaded nanosized transethosomes for vaginal permeation enhancement: Formulation, statistical optimization and clinical evaluation in anovulatory polycystic ovary syndrome

Abstract Bio-identical progesterone (PRG) is an exogenous female steroidal hormone which is used for treatment of polycystic ovary syndrome (PCOS). However, it suffers from poor bioavailability due to hepatic metabolism and poor solubility. The target of this work was to evaluate and statistically optimize PRG-loaded nanovesicle transethosomes (NVTEs) based in mucoadhesive gel for transvaginal delivery of PRG as potential luteal-phase support. A 24 full factorial design was used to explore the effect of phosphatidylcholine (PC), Tween 80, cetyltrimethyl ammonium bromide and ethanol concentration on particle size, entrapment efficiency (EE%), % in vitro PRG release after 24 h and transvaginal flux. PRG-loaded NVTEs were prepared by injection sonication method. The results revealed that the mean particle sizes ranged from 133.3 ± 3.42 to 349.5 ± 1.24 nm, zeta potential ranged from –23.5 ± 3.84 to +74.6 ± 4.97 mV, EE% ranged from 87.93 ± 3.58 to 97.05 ± 2.61%, % PRG release ranged from 50.9 ± 2.75 to 90.69 ± 2.07 and transvaginal flux ranged from 0.274 ± 0.03 to 0.531 ± 0.04 mg/cm2/h. The optimized formulation was subjected to transmission electron microscope for morphological examination and then incorporated in the mucoadhesive vaginal gel using Carbopol 974, hydroxyl propyl methylcellulose and sodium alginate. The optimized formulation was clinically studied in anovulatory PCOS and showed a significant increase in the serum PRG, endometrial thickness, echogenicity degree and the pregnancy rate. Briefly, PRG-loaded NVTEs vaginal gel might be a promising formulation for luteal phase support and increase pregnancy rate in anovulatory PCOS.

Preparation and optimization of tablets containing a self-nano-emulsifying drug delivery system loaded with rosuvastatin

Abstract Background: Rosuvastatin (ROS) calcium is the latest synthetic drug in the statin group that has an anti-hyperlipidemic activity. It is available as tablets, and its poor aqueous solubility, slow dissolution rate and low-absorption extent result in less than 20% bioavailability and about 80% being excreted unchanged in the feces without absorption. Objective: To utilize nanotechnology to reformulate ROS as a self-nano-emulsifying drug delivery system (SNEDDS), and utilizing design optimization to fabricate the SNEDDS as a tablet. Methods: The solubility of ROS in different oils, surfactants and co-surfactants was tested. Pseudo-ternary phase diagrams were developed and various SNEDDS formulations were prepared and evaluated regarding globule size, self-emulsification, viscosity and transmittance. The optimized system was examined using transmission electron microscopy. The self-nano-emulsifying tablets were prepared using two types of nano-silica and different percentages of Avicel as a binder and Ac-Di-Sol as a disintegrant. The prepared tablets were evaluated for their physicochemical properties. Bioavailability in human volunteers was assessed. Results: A SNEDDS system was successfully developed with a droplet size range of 15 nm and a composition of 10% Labrafac, 80% Cremophore RH40 and 10% Propylene glycol. The optimized tablet formula contained: hydrophilic nano-silica, 3% Ac-Di-Sol and 30% Avicel. The pharmacokinetic study revealed that the bioavailability was enhanced by more than 2.4-fold compared with the commercially available tablet. Conclusions: Tablets containing SNEDDS loaded with ROS represent a promising novel formula that has higher gastrointestinal absorption and enhanced systemic bioavailability.