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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.)

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.)

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.)