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Purpose: Improving the treatment of psoriasis is a serious challenge today. Psoriasis is an immune-mediated skin condition affecting 125 million people worldwide. It is commonly treated with cyclosporine-A (CsA) and dithranol (DTH). CsA suppresses the activation of T-cells, immune cells involved in forming psoriatic lesions. Meanwhile, DTH is a potent anti-inflammatory and anti-proliferative drug that effectively reduces the severity of psoriasis symptoms such as redness, scaling, and skin thickness. CsA and DTH belong to BCS class II with limited oral bioavailability. We aim to develop a drug delivery system for topical co-delivery of CsA and DTH, exploring its therapeutic potential., Methods: Firstly, we developed a niosomal drug delivery system based on ceramide IIIB to form Cerosomes. Cerosomes were prepared from a mixture of Ceramide, hyaluronic acid, and edge activator using a thin-film hydration technique. To co-deliver CsA and DTH topically for the treatment of psoriasis. These two hydrophobic drugs encapsulated into our synthesized positively charged particle cerosomes., Results:  Cerosomes had an average particle size of (222.36 nm± 0.36), polydispersity index of (0.415±0.04), Entrapment Efficiency of (96.91%± 0.56), and zeta potential of (29.36±0.38mV) for selected formula. In vitro, In silico, in vivo, permeation, and histopathology experiments have shown that cerosomes enhanced the skin penetration of both hydrophobic drugs by 66.7% compared to the CsA/DTH solution. Imiquimod (IMQ) induced psoriatic mice model was topically treated with our CsA/DTH cerosomes. We found that our formulation enhances the skin penetration of both drugs and reduces psoriasis area and severity index (PASI score) by 2.73 times and 42.85%, respectively, compared to the CsA/DTH solution. Moreover, it reduces the levels of proinflammatory cytokines, TNF-α, IL-10, and IL-6 compared to CsA/DTH solution administration., Conclusion: The Cerosomes nano-vesicle-containing CsA/DTH represents a more promising topical treatment for psoriasis, giving new hope to individuals with psoriasis, compared to commercial and other conventional alternatives., Competing Interests: The authors declare no conflict of interest., (© 2024 Elhabal et al.)

Objective: Clonazepam (CP) is a potent long-acting nitrobenzodiazepine derivative that could be used for targeting peripheral benzodiazepine receptors. Phospholipid magnesome is a new vesicular nanosystem recently developed for brain targeting. Improving the uptake of 131 I-CP to the brain might be effective for the diagnosis and/or radiotherapy of certain brain diseases and/or tumors., Methods: CP was radiolabeled with 131 I using direct electrophilic substitution reaction. Quality control of 131 I-CP was performed using different techniques. Different formulas of 131 I-CP were prepared and characterized according to particle size and polydispersity index. The structural features of the optimized formula were then interpreted using transmission electron microscopy and scanning electron microscopy, whereas pharmacokinetic and in vivo behaviors were estimated using the intravenous and intranasal delivery routes., Results: The heart and blood demonstrated lower uptake of 131 I-CP, which inevitably decreased the nontarget effects of radioiodine. Intranasally administered 131 I-CP-loaded magnesomes (INMg) had noticeably higher brain uptake (7.1 ± 0.09%ID/g) with rapid onset of action within 5 min and effective pharmacokinetic behavior. INMg had a drug targeting efficiency and nose-to-brain direct transport percentage of 121.1% and 94.6%, respectively as well as a relative bioavailability of 441.04 ± 75.5%., Conclusion: The present study showed that 131 I-CP-loaded magnesomes can be a beneficial brain-targeting approach for improving the diagnosis and/or radiotherapy of certain brain diseases., (Copyright © 2021. Published by Elsevier B.V.)

The objective of this work was to design a diclofenac epolamine (DE) flash tablets (FTs) intended to dissolve in the mouth saliva, thereby improving the DE bioavailability and reducing its first-pass liver metabolism. Design-Expert software was used to build a 3 1 .2 2 full factorial design (12 runs). FTs were fabricated using lyophilization process. The dissolution response was selected to pick the optimized run. The results indicate that the optimized run (R1) showed the fastest drug dissolution (total dissolution in 12 min). The predicted run (Rp) showed a desirability of about 0.93. Differential scanning calorimetry(DSC) analysis results showed a decrease in the drug melting point of the R1 formulation. Fourier-transform infrared spectroscopy (FTIR) showed the compatibility of the drug with other components of formulation, X-ray powder diffraction (XRPD) analysis showed the evolution of the drug physical state from a crystalline to an amorphous form and scanning electron microscopy(SEM) divugled the disappearance of drug crystals in gelatin strands. The results of the pharmacokinetic study performed in 6 human volunteers evidenced an increase in the maximum DE concentration in plasma and, consequently, an increased bioavailability of the FT formulation as compared with a reference formulation(Fr). Concisely, the developed FTs (R1) showed promising results which could be able to enhance oral bioavailability, reduce the therapeutic dose of the drug, and abate of the complications accompanied with conventional dosage forms. Graphical abstract.

Ethylmorphine hydrochloride (EtM) is a derivative of morphine used as analgesic to treat severe pain in case of cancer and bone injury. This study aimed to formulate and evaluate core in cup tablets containing 2 doses of EtM, the cup was formulated as lyophilized oro-dispersible tablet (ODT) for immediate release (IR), and the core was formulated as directly compressed tablet for sustained release (SR). Factorial design was adopted for the optimization of tablets prepared via lyophilized form and direct compression techniques: a 4 1 .2 2 design was used for the former, while a 3 2 one was used for the latter. All prepared tablets showed acceptable physical properties which were in accordance with pharmacopeial standards. Two lyophilized ODTs (F9 and F10) formulae were selected as the cup for instant release. While one directly compressed tablet formula (S6) was selected based on the in vitro release profile to represent the sustained core, the outcome was 2 core in cup tablets, namely B1 and B2 which were evaluated for their in vivo absorption and showed a maximum plasma concentration (Cp max ) of 354.12 ± 17.55 ng/mL and 350.82 ± 12.15 ng/mL respectively attained after 3.0 h which were twofolds significantly higher in comparison to the market tablet with Cp max of only 172.05 ± 12.53 ng/mL attained after 2.20 ± 0.24 h.

Objective: The purpose of this study was to prepare proniosomal vesicles of Telmisartan (TEL) to be compressed into tablets which will be further evaluated in vitro and in vivo., Materials and Methods: An experimental design was adopted using surfactants of different HLB values (span 40-brij 35), different cholesterol ratios (20-50%) and different phospholipid types (egg yolk-soyabean). Different responses were measured followed by tablet manufacturing. The highest EE was shown in F3 (85%) while the lowest value was obtained in F7 (8.4%). Finally, zeta potential results were in the range of -0.67 to -27.6 mv. Compressibility percent revealed that F5 showed an excellent flowability characteristic with a value of 9.74±1.61 while F3 and F6 showed good flowability characteristics. By the end of the release, F6 showed approximately 90% drug release., Results: F6 was selected for the in vivo study; C max was increased by 1.5-fold while AUC 0-∞ also increased significantly by 3-fold when compared with commercial tablet and finally, t max was increased by 3-fold indicating sustained release pattern. The relative bioavailability was also increased by 3.2-fold., Conclusion: The results of this study suggested that the formulation of compressed tablets containing more stable proniosomal powder extended the release of TEL and increased its bioavailability as well., Competing Interests: The authors declare that they have no conflict of interests., (© 2020 Teaima et al.)

In our study, the potential of bilosomes as novel vesicular carrier for the cutaneous delivery of the sulphone compound, Dapsone, for topical treatment of acne was investigated. The effect of different formulation variables (type and concentration of bile salt, and molar ratio of Span 60:cholesterol) on the properties of DPS-loaded bilosomes was investigated using a full factorial design. Design Expert software was used for data analysis and optimization of DPS-loaded bilosomes. The optimized bilosomes, chosen on the basis of their superior properties giving maximum entrapment, in vitro release after different time intervals and RE% with minimum vesicle size. Results showed that the bilosome system prepared using Span ® 60: Cholesterol (5:1) and containing 0.25 M sodium deoxycholate as the bile salt was found to obey these criteria, with a desirability value of 0.637. Therefore, this system was chosen for further assessment for its morphological properties, zeta potential, thermal analysis using differential scanning calorimetry and X-ray diffractometry. Results revealed that the chosen bilosomes were spherical in shape with no aggregation, and contained DPS in a molecularly dispersed amorphous form. Finally, the capability of the optimized DPS-loaded bilosomes to deliver DPS through rat skin layers will be investigated and compared with that of DPS alcoholic solution. Results showed that the amounts of DPS retained in the skin treated with DPS-loaded bilosomes, and DPS alcoholic solution after 24 h were found to be 170.57 ± 55.12 and 120.24 ± 10.7 µg/mL, respectively, representing about 1.5-fold higher drug retained in the bilosomes-treated skin. Finally, the safety and the tolerability of the prepared bilosomes were assessed using histopathological examination, and revealed that the control untreated skin sections and skin sections treated with DPS-loaded bilosomes showed normal histological structures characterized by absence of defects or inflammation. Such results can be considered a good addition in the field of pharmaceutical drug delivery for effective topical therapy of acne.

Objectives: This study was aimed to develop dual-purpose natamycin (NAT)-loaded niosomes in ketorolac tromethamine (KT) gels topical ocular drug delivery system to improve the clinical efficacy of natamycin through enhancing its penetration through corneal tissue and reducing inflammation associated with Fungal keratitis (FK)., Significance: Nanosized carrier systems, as niosomes would provide great potential for improving NAT ocular bioavailability.NAT niosomal dispersion formulae were prepared and then incorporated in 0.5%KT gels using different mucoadhesive viscosifying polymers., Methods: Niosomes were prepared using the reverse-phase evaporation technique. In vitro experimental, and in vivo clinical evaluations for these formulations were done for assessment of their safety and efficacy for treatment of Candida Keratitis in Rabbits. In vitro release study was carried out by the dialysis method. In vivo and histopathological studies were performed on albino rabbits., Results: NAT niosomes exhibited high entrapment efficiency percentage (E.E%) up to96.43% and particle size diameter ranging from 181.75 ± 0.64 to 498.95 ± 0.64 nm, with negatively charged zeta potential (ZP). NAT niosomal dispersion exhibited prolonged in vitro drug release (40.96-77.49% over 24h). NAT-loaded niosomes/0.5%KT gel formulae revealed retardation in vitro release, compared to marketed-product (NATACYN ®) and NAT-loaded niosomes up to57.32% (F8). In vivo experimental studies showed the superiority for F8 in treatment of candida keratitis and better results on corneal infiltration and hypopyon level. These results were consistent with histopathological examination in comparison with F5 and combined marketed products (NATACYN ® and Ketoroline ® )., Conclusions: This study showed that F8 has the best results from all pharmaceutical in vitro evaluations and a better cure percent in experimental application and enhancing the prolonged delivery of NAT and penetrating the cornea tissues.

Dapsone (DPS) is a unique sulfone with antibiotic and anti-inflammatory activity. Owing to its dual action, DPS has a great potential to treat acne. Topical DPS application is expected to be effective in treatment of mild to moderate acne conditions. Invasomes are novel vesicles composed of phosphatidylcholine, ethanol, and one or mixture of terpenes of enhanced percutaneous permeation. In this study, DPS-loaded invasomes were prepared using the thin film hydration technique. The effect of different terpenes (Limonene, Cineole, Fenchone, and Citral) in different concentrations on the properties of the prepared DPS-loaded invasomes was investigated using a full factorial experimental design, namely, the particle size, drug entrapment, and release efficiency. The optimized formulation was selected for morphological evaluation which showed spherical shaped vesicles. Further solid-state characterization using differential scanning calorimetry and X-ray diffractometry revealed that the drug was dispersed in an amorphous state within the prepared invasomes. Finally, the ability of the prepared DPS-loaded invasomes to deliver DPS through the skin was investigated in vivo using wistar rats. The maximum in vivo skin deposition amount of DPS was found to be 4.11 mcg/cm 2 for invasomes versus 1.71 mcg/cm 2 for the drug alcoholic solution, representing about 2.5-fold higher for the invasomes compared to the drug solution. The AUC0-10 calculated for DPS-loaded invasomes was nearly 2-fold greater than that of DPS solution (14.54 and 8.01 mcg.h/cm 2 for the optimized invasomes and DPS solution, respectively). These results reveal that the skin retention of DPS can be enhanced using invasomes.

Lornoxicam is an anti-inflammatory drug used to relieve rheumatoid arthritis pain, but the low water solubility and bitter taste of the drug present challenges for formulation as fast disintegrating tablets (FDTs). Complexation of the drug with β-cyclodextrin was initially carried out to increase the drug solubility and to mask its bitter taste. Tablets were prepared by direct compression of drug complex (DC), F-Melt, mannitol, crospovidone, and sodium starch glycolate (SSG). FDTs were characterized in terms of disintegration time (DT) and dissolution. A bioequivalence study was carried out using (Zeficam® tablets (Eva Pharma) as reference with the help of human volunteers (n = 4). The chosen formula (F2, DC 24 mg, F-Melt 88.4 mg, and crospovidone 5 mg) exhibited the shortest in vitro (18 s) and in vivo DT (13 s), and the percent drug released after Q6min was 95.90%. Following administration of F2 and Zeficam®, the respective maximum drug plasma concentrations (C max ) were 510 and 532.5 ng/mL, at times (T max ) of 1 and 2.5 h, of mean residence times (MRTs) of 12.25 and 11.35 h and of areas under the plasma curve [AUC(0-24)] of 5080.253 and 4815.775 ng/h/mL. There were significant differences in T max and MRT of both treatments (p < 0.05). Moreover, the volunteers found F2 to be palatable. FDTs could be considered as promising dosage forms for lornoxicam as they exhibited a short in vivo DT and an increased rate of drug release and attained a relative bioavailability of 105.49%. This could offer a fast relief of pain accompanying rheumatoid arthritis.

Context: Muscle spasm is a painful involuntary contraction of muscles, which causes involuntary movement and distortion. Chlorzoxazone is a centrally acting muscle-relaxant with sedative properties, but given orally, it is hepatically metabolized leading to decreased bioavailability., Objective: Orodispersible tablets (ODTs) of chlorzoxazone were formulated using two different approaches; by coprocessed excipients (CE) or by liquisolid (LS) technique., Materials and Methods: Pharmaburst ® 500, Starlac ® , Pearlitol flash ® , Prosolv ® odt and F-melt ® were used as coprocessed superdisintegrants, whereas in LS, Avicel ® PH101, Microcelac ® 100 and Cellactose ® 80 were used as carriers, while Aerosil ® 200 was the coating material. ODTs were evaluated in terms of weight and thickness variations, drug content, hardness, friability, wetting time, dissolution, disintegration time (DT) and palatability., Results: In vitro DT of CE-ODTs ranged from 26.43 ± 1.693 s to >180 s, whereas it was between 25.42± 0.203 s to >180 s in LS-ODTs. Complete drug release within 15 min was attained by CE1 prepared with 92.5 mg Pharmaburst ® 500. In vivo DT of CE1 and LS3 were 19.779 ± 0.810 and 18.105 ± 0.423 s, respectively, using six volunteers. Volunteers found that CE1 had more acceptable taste and was more palatable than LS3., Conclusion: It was concluded that chlorzoxazone ODTs could be successfully formulated using either CE or LS techniques and be used as novel dosage forms for pediatrics and geriatrics showing improved drug release. Moreover, CE technique was superior to LS technique in terms of palatability.

Context: Pravastatin sodium (PVS) is a freely water-soluble HMG-CoA inhibitor that suffers from instability at gastric pH, extensive first pass metabolism, short elimination half-life (1-3 h) and low oral bioavailability (18%)., Objective: To overpower these drawbacks and to maximize drug absorption at its main site of absorption at the duodenum, enteric surface-coated PVS-loaded nanocubosomal dispersions were presented., Materials and Methods: Glyceryl monooleate (GMO)-based dispersions were developed by the fragmentation or the liquid precursor methods using Pluronic® F127 or Cremophor® EL as surfactants. As a challenging enteric-coating approach, the promising dispersions were surface-coated via lyophilization with Eudragit® L100-55; a duodenum-targeting polymer. The drug content, particle size, zeta potential, morphology and release studies of PVS-loaded dispersions were evaluated before and after surface-coating. Compared to an aqueous PVS solution, the pharmacokinetics of the best achieved system (E-F8) was evaluated (UPLC-MS/MS) in rats., Results: The enteric surface-coated nanocubosomal dispersions were more or less spherical in shape and showed high drug-loading, negative zeta potential values and fine-tuned biphasic drug-release patterns characterized by retarded (2 h) and sustained (10 h) phases in pH 1.2 and pH 6.8, respectively. E-F8 system showed significantly (p< 0.05) higher oral bioavailability, delayed T max and prolonged MRT 0-∞ following oral administration in rats., Conclusions: The duodenum-triggering potential and the controlled-release characteristics of the best achieved system for smart PVS delivery were revealed.

Context: Muscle spasm needs prompt relief of symptoms. Chlorzoxazone is a centrally muscle relaxant., Objectives: The aim of this study was to prepare chlorzoxazone orodispersible tablets (ODTs) allowing the drug to directly enter the systemic circulation and bypassing the first-pass metabolism for both enhancing its bioavailability and exerting a rapid relief of muscular spasm., Materials and Methods: ODTs were prepared by direct compression method using Pharmaburst®500, Starlac®, Pearlitol flash®, Prosolv® odt and F-melt® as co-processed excipients. Three ratios of the drug to the other excipients were used (0.5:1, 1:1 and 2:1)., Results and Discussion: All ODTs were within the pharmacopeial limits for weight and content. ODTs containing Pharmaburst®500 showed the shortest wetting time (∼45.33 s), disintegration time (DT) (∼43.33 s) and dissolution (Q 15min 100.63%). By increasing the ratio of CLZ: Pharmaburst®500 from 0.5:1 to 1:1 and 2:1, the DT increased from 26.43 to 28.0 and 43.33 s, respectively. By using Prosolv® odt, ODTs failed to disintegrate in an acceptable time >180 s. DT of ODTs using different co-processed excipients can be arranged as follows: Pharmaburst® 500 < F-melt® max (0.333 h) compared with Myofen® capsules (250 mg CLZ) (1.083 h) which is considered a promising treatment, especially for the rapid relief of muscle spasm., Conclusion: It could be concluded that orodispersible tablets are a promising carrier for CLZ designed for management of muscle spasm due to the enhanced dissolution and rapid absorption of the drug through the oral mucosa.

Meloxicam (Mel) is a non-steroidal potent anti-inflammatory drug with effective analgesic effect for various situations; e.g. postoperative pain. The early systemic exposure to Mel and hence the rapid onset of pharmacological action is limited by its poor water solubility; a situation which may be more pronounced during acute pain episode because of reduced gastric motility that affects disintegration and dissolution of solid dosage forms. To overcome delayed absorption of Mel, improvement in the dissolution behavior of Mel is essential. Firstly, Mel spherical crystalline agglomerates (SCA) were prepared. Secondly, selected Mel SCA were integrated into intraoral fast disintegrating (OF) and edible (EF) films, they possess larger surface area that leads to rapid disintegration and release of the drug into the oral cavity within seconds and hence a rapid onset of action could be achieved. Stability study of formulations resulting in faster and higher extent of dissolution and suitable mechanical properties (G3 and G12) revealed their physical and chemical stability after three months of storage under different conditions. Both G3 and G12 successfully offered rapid absorption rate and accordingly an earlier systemic exposure to Mel compared to Mobic tablets as revealed by significantly earlier T max and higher AUC 0-0.5h and AUC 0-4h . T max following G3 fast disintegrating film administration was comparable to that reported following Mel parenteral administration but avoiding patient inconvenience. Both films may be suitable alternative to conventional oral and intramuscular Mel especially when earlier onset of action is required (in acute conditions).

Granisetron hydrochloride is a potent antiemetic yet experiencing first pass metabolism. Ketorolac tromethamine is a potent analgesic NSAID that is known to cause gastrointestinal complications. The purpose of this study is to prepare combined in situ nasal copolymer thermal gel combining both drugs for the management of postoperative and cancer associated nausea, vomiting and pain while avoiding the problems associated with their therapy. In situ gelling nasal formulations with/without different mucoadhesive polymers were prepared and evaluated. Viscosity of different formulations was measured and correlated to in-vitro drug release. Selected formulae were evaluated for in-vivo mucociliary transit time. Based on in-vitro release pattern and mucociliary transit time, the selected formula F4 was evaluated for chemical and thermal anti-nociception activity in rats following intranasal or intraperitoneal administration. Only the intra-nasal administration of the selected formulation F4 showed significant analgesia against chemical nociception during both the early and late phases. Also, intranasal administration of the selected formulation F4 showed significant analgesia against thermal nociception. F4 intranasal formulation may offer higher therapeutic value than oral administration as it may not only avoid granisetron first pass metabolism but may also minimize ketorolac gastrointestinal adverse effects as well., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Pravastatin sodium (PVS) is a hydrophilic HMG-CoA reductase inhibitor that is mainly absorbed from duodenum. PVS has a short elimination half-life (1-3 h), suffers from instability at gastric pH, extensive hepatic first-pass metabolism and low absolute bioavailability (18%). The current work aimed to develop enteric surface-coated spanlastic dispersions as controlled-release duodenum-triggered systems able to surmount PVS drawbacks. PVS-loaded spanlastic dispersions were prepared by ethanol-injection method using span(®) 60. Tween(®) 60 and Tween(®) 80 were explored as edge activators. As a novel approach, the fine spanlastic dispersions were surface-coated with an enteric-polymer (Eudragit(®) L100-55) via freeze-drying. The systems were evaluated, before and after enteric-coating, for particle size, zeta potential, PVS entrapment efficiency (EE%), morphology and PVS release studies. PVS pharmacokinetics from the best achieved system and an aqueous solution were estimated in rats by UPLC-MS/MS. The best achieved enteric surface-coated spanlastic dispersion (E-S6) displayed spherical nanosized vesicles (647.60 nm) possessing negative zeta potential (-6.93 mV), promising EE% (63.22%) and a biphasic drug-release pattern characterized by a retarded-release phase (0.1 N HCl, 2 h) and a controlled-release phase (pH 6.8, 10 h). The higher Cmax, delayed Tmax, prolonged MRT(0-∞), longer elimination t50% and enhanced oral bioavailability unravel E-S6 potential for oral PVS delivery., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Granisetron hydrochloride (granisetron) is a potent antiemetic that has been proven to be effective in acute and delayed emesis in cancer chemotherapy. Granisetron suffers from reduced oral bioavailability (≈60%) due to hepatic metabolism. In this study the combined advantage of provesicular carriers and buccal drug delivery has been explored aiming to sustain effect and improve bioavailability of granisetron via development of granisetron provesicular buccoadhesive tablets with suitable quality characteristics (hardness, drug content, in vitro release pattern, exvivo bioadhesion and in vivo bioadhesion behavior). Composition of the reconstituted niosomes from different prepared provesicular carriers regarding type of surfactant used and cholesterol concentration significantly affected both entrapment efficiency (%EE) and vesicle size. Span 80 proniosome-derived niosomes exhibited higher encapsulation efficiency and smaller particle size than those derived from span 20. Also, the effect of %EE and bioadhesive polymer type on in vitro drug release and in vivo performance of buccoadhesive tablets was investigated. Based on achievement of required in vitro release pattern (20-30% at 2h, 40-65% at 6h and 80-95% at 12h), in vivo swelling behavior, and in vivo adhesion time (>14 h) granisetron formulation (F19, 1.4 mg) comprising HPMC:carbopol 974P (7:3) and maltodextrin coated with the vesicular precursors span 80 and cholesterol (9:1) was chosen for in vivo study. In vivo pharmacokinetic study revealed higher bioavailability of buccal formulation relative to conventional oral formulation of granisetron (AUC0-∞ is 89.97 and 38.18 ng h/ml for buccal and oral formulation, respectively). A significantly lower and delayed Cmax (12.09±4.47 ng/ml, at 8h) was observed after buccal application compared to conventional oral tablet (31.66±10.15 ng/ml, at 0.5 h). The prepared provesicular buccoadhesive tablet of granisetron (F19) might help bypass hepatic first-pass metabolism and improve bioavailability of granisetron with the possibility of reducing reported daily dose (2mg) and reducing dosing frequency., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Frequent instillation of terbinafine hydrochloride (T HCl) eye drops (0.25%, w/v) is necessary to maintain effective aqueous humor concentrations for treatment of fungal keratitis. The current approach aimed at developing potential positively charged controlled-release polymeric nanoparticles (NPs) of T HCl. The estimation of the drug pharmacokinetics in the aqueous humor following ocular instillation of the best-achieved NPs in rabbits was another goal. Eighteen drug-loaded (0.50%, w/v) formulae were fabricated by the nanopreciptation method using Eudragit® RS100 and chitosan (0.25%, 0.5%, and 1%, w/v). Soybean lecithin (1%, w/v) and Pluronic® F68 (0.5%, 1%, and 1.5%, w/v) were incorporated in the alcoholic and aqueous phases, respectively. The NPs were evaluated for particle size, zeta potential, entrapment efficiency percentage (EE%), morphological examination, drug release in simulated tear fluid (pH 7.4), Fourier-transform IR (FT-IR), X-ray diffraction (XRD), physical stability (2 months, 4°C and 25°C), and drug pharmacokinetics in the rabbit aqueous humor relative to an oily drug solution. Spherical, discrete NPs were successfully developed with mean particle size and zeta potential ranging from 73.29 to 320.15 nm and +20.51 to +40.32 mV, respectively. Higher EE% were achieved with Eudragit® RS100-based NPs. The duration of drug release was extended to more than 8 h. FT-IR and XRD revealed compatibility between inactive formulation ingredients and T HCl and permanence of the latter's crystallinity, respectively. The NPs were physically stable, for at least 2 months, when refrigerated. F5-NP suspension significantly (P<0.05) increased drug mean residence time and improved its ocular bioavailability; 1.657-fold.

Terbinafine hydrochloride (T-HCl) is recommended for the management of fungal keratitis. To maintain effective aqueous humor concentrations, frequent instillation of T-HCl drops is necessary. This work aimed to develop alternative controlled-release in situ ocular drug-loaded nanoemulsion (NE) gels. Twelve pseudoternary-phase diagrams were constructed using oils (isopropyl myristate/Miglyol 812), surfactants (Tween 80/Cremophor EL), a co-surfactant (polyethylene glycol 400) and water. Eight drug-loaded (0.5%, w/v) NEs were evaluated for thermodynamic stability, morphology, droplet size and drug release in simulated tear fluid (pH 7.4). Following dispersion in gellan gum solution (0.2%, w/w), the in situ NE gels were characterized for transparency, rheological behavior, mucoadhesive force, drug release and histopathological assessment of ocular irritation. Drug pharmacokinetics of sterilized F31 [Miglyol 812, Cremophor EL: polyethylene glycol 400 (1:2) and water (5, 55 and 40%, w/w, respectively)] in situ NE gel and oily drug solution were evaluated in rabbit aqueous humor. The NEs were thermodynamically stable and have spherical droplets (<30 nm). The gels were transparent, pseudoplastic, mucoadhesive and showed more retarded zero-order drug release rates. F31 in situ NE gel showed the least ocular irritation potential and significantly (P<0.01) higher C(max), delayed T(max), prolonged mean residence time and increased bioavailability., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Itraconazole (ITZ) crystalline nanoparticles were prepared using relatively simple, low-cost sonoprecipitation technique, in which both the solvent and antisolvent were organic in nature. The effect of stabilizer type (hydroxypropyl methylcellulose, hydroxypropyl cellulose, Inutec SP1®, and pluronic F127), drying method (oven and freeze drying) and matrix former used (Avicel PH101, and Aerosil®200) on the dissolution performance as a key characteristic of nanocrystals was evaluated. In 10 min, all of the prepared nanocrystals showed 3.77-8.59 times improvement in percent drug dissolved compared to pure ITZ. Concerning the effect of stabilizer type, the following rank order can be given: pluronic F127 ≥ hydroxypropyl cellulose ≥ hydroxypropyl methylcellulose (HPMC) > inutec SP1. Freeze-dried ITZ nanocrystals containing Avicel PH 101 showed better dissolution rate compared to other nanocrystals. The chemical structure of itraconazole nanocrystals was not changed as revealed by Fourier transform infrared. Stability study of selected nanocrystals (F5, F7, and F8) revealed physical and chemical stability of F7 and F8, while a decrease in dissolution rate of F5 was observed (although being chemically stable) when stored under high relative humidity conditions. Although inutec is less potent than pluronic F127 and HPMC regarding their effect on dissolution rate enhancement, it is equipotent to pluronic F127 in preserving the rapid drug dissolution.

This paper describes the preparation of two layered device comprising of tenoxicam containing layer and a drug free membrane layer based on Geomatrix Technology. Our device based on bilaminated films which produced by a casting/solvent evaporation technique. The drug-hydroxypropyl methylcellulose (HPMC) layer was covered by drug free membrane layer composed of a mixture of different ratios of HPMC and ethyl cellulose (EC). The prepared devices were evaluated for thickness, weight, drug content uniformity, water absorption capacity and in-vitro drug release. The films were also evaluated for appearance, smoothness and transparency. The influence of drug free membrane layer composition and thickness on the drug release pattern was studied on 12 devices (D1 to D12). The results indicate that, the release of drug from HPMC matrixes without the drug free membrane layer was fast and follows diffusion controlled mechanism. The release of drug from the devices D1, D4, D9 and D12 follow the same mechanism, while the release of drug from other devices become linear with time (zero order) and extended for long time especially when thickness and the ratio of EC was increased in the drug free membrane layer. From this study it is concluded that, changing the geometry of drug layer by addition of drug free membrane layer and changing its composition and thickness plays an important role in determining whether the drug free membrane layer is rate-controlling or modulator membrane. Hence it can facilitate the development of different pharmaceutical products with different release pattern.