Nasal administration of metoclopramide from different dosage forms: in vitro, ex vivo, and in vivo evaluation

Tadpole-Like Anisotropic Polymer/Lipid Janus Nanoparticles for Nose-to-Brain Drug Delivery: Importance of Geometry, Elasticity on Mucus-Penetration Ability

Asymmetric geometry (aspect ratio >1), moderate stiffness (i.e., semielasticity), large surface area, and low mucoadhesion of nanoparticles are the main features to reach the brain by penetrating across the nasal mucosa. Herein, a new application has been presented for the use of multifunctional Janus nanoparticles (JNPs) with controllable geometry and size as a nose-to-brain (N2B) delivery system by changing proportions of Precirol ATO 5 and polycaprolactone compartments and other operating conditions. To bring to light the N2B application of JNPs, the results are presented in comparison with polymer and solid lipid nanoparticles, which are frequently used in the literature regarding their biopharmaceutical aspects: mucoadhesion and permeability through the nasal mucosa. The morphology and geometry of JPs were observed via cryogenic-temperature transmission electron microscopy images, and their particle sizes were verified by dynamic light scattering, atomic force microscopy, and scanning electron microscopy. Although all NPs showed penetration across the mucus barrier, the best increase in penetration was observed with asymmetric and semielastic JNPs, which have low interaction ability with the mucus layer. This study presents a new and promising field of application for a multifunctional system suitable for N2B delivery, potentially benefiting the treatment of brain tumors and other central nervous system diseases.

Fabrication and Characterization of Clozapine Nanoemulsion Sol-Gel for Intranasal Administration

Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia. However, it causes many adverse drug reactions (ADRs), which lead to poor treatment outcomes. Nose-to-brain (N2B) drug delivery offers a promising approach to reduce peripheral ADRs by minimizing systemic drug exposure. The aim of the present study was to develop and characterize clozapine-loaded nanoemulsion sol-gel (CLZ-NESG) for intranasal administration using high energy sonication method. A range of oils, surfactants, and cosurfactants were screened with the highest clozapine solubility selected for the development of nanoemulsion. Pseudoternary phase diagrams were constructed using a low-energy (spontaneous) method to identify the microemulsion regions (i.e., where mixtures were transparent). The final formulation, CLZ-NESG (pH 5.5 ± 0.2), comprising 1% w/w clozapine, 1% w/w oleic acid, 10% w/w polysorbate 80/propylene glycol (3:1), and 20% w/w poloxamer 407 (P407) solution, had an average globule size of ≤30 nm with PDI 0.2 and zeta potential of -39.7 ± 1.5 mV. The in vitro cumulative drug release of clozapine from the nanoemulsion gel at 34 °C (temperature of nasal cavity) after 72 h was 38.9 ± 4.6% compared to 84.2 ± 3.9% with the control solution. The permeation study using sheep nasal mucosa as diffusion barriers confirmed a sustained release of clozapine with 56.2 ± 2.3% cumulative drug permeated after 8 h. Additionally, the histopathological examination found no severe nasal ciliotoxicity on the mucosal tissues. The thermodynamic stability studies showed that the gel strength and viscosity of CLZ-NESG decreased after temperature cycling but was still seen to be in "gel" form at nasal temperature. However, the accelerated storage stability study showed a decrease in drug concentration after 3 months, which can be expected at elevated stress conditions. The formulation developed in this study showed desirable physicochemical properties for intranasal administration, highlighting the potential value of a nanoemulsion gel for improving drug bioavailability of clozapine for N2B delivery.

The potential of intranasal delivery of nanocrystals in powder form on the improvement of zaleplon performance: in-vitro, in-vivo assessment

OBJECTIVE

The present work focuses on improving zaleplon (ZAP) performance through nanosizing its insoluble particles which were then delivered intranasally in powder form.

SIGNIFICANCE

Since nanopowders have an exceptional ability to cross cell membrane, their absorption is facilitated in the solid form. Hence, delivering insoluble ZAP nanocrystals (NC) through intranasal route improves its bioavailability due to both nanosization and the escape of hepatic metabolism.

METHODS

Nanocrystals were prepared by anti-solvent precipitation followed by probe sonication in presence of Soluplus^®, Poloxamer-188 (0.25%), sodium lauryl sulfate (0.5%), and mannitol. Physicochemical evaluation of the prepared NC was done by DSC and XRPD. TGA was performed for stability detection. Ex vivo permeation study through isolated cattle nasal mucosal membrane, in addition to an in vivo bioavailability study was performed for assessment of the prepared NC.

RESULTS

Nanosization to 200 nm contributed to the enhancement in dissolution ∼100% within 30 min and reduced half-life to 1.63 min. Confirmation of adsorption of polymers over NC' surface was elucidated. TGA confirmed their thermal stability. Ex vivo permeation study showed a 2.7 enhancement ratio in favor of the prepared NC. Both the extent and rate of NC absorption through nasal mucosa of rabbits were significantly higher (p ˂ .05) than in case of oral tablets. The relative bioavailability of NC was increased 3.14 times as compared to the Sleep aid^® tablets.

CONCLUSION

The intranasal delivery of nanoscale ZAP powder proved to be a successful alternative to oral formulations that suffer poor absorption and limited bioavailability.

Sublingual insulin administration: application of hydroxypropyl beta-cyclodextrin and poloxamer188 as permeation enhancers

The objective of this investigation is to investigate the feasibility of sublingual insulin administration. Insulin solutions formulated with permeation enhancers (HPβCD/poloxamer 188) and their in-vitro and in-vivo performances were evaluated. Thereafter, insulin fast-dissolving film was further developed to have similar properties, upon dissolving the film, of the optimized insulin solution. In-vitro performance was evaluated via effect of HPβCD and/or poloxamer 188 concentration across cellulose acetate membrane and porcine esophagus. In-vivo performance was evaluated via pharmacodynamic and pharmacokinetic profiles of insulin solution administered. Cumulative amounts of insulin permeated at 60 min formulated with HPβCD (5%), poloxamer 188 (0.5%), and their combination were 1.31, 3.23, and 4.99 IU/cm², respectively, indicating an additive effect of combination of HPβCD and poloxamer 188. Insulin-induced hypoglycemic effect was observed for insulin solutions with combination of HPβCD and poloxamer 188 after sublingual administration to Sprague-Dawley rats. Microscopic evaluation of porcine oesophageal tissue indicates that HPβCD and poloxamer 188 are safe. Furthermore, the cumulative amount permeated across cellulose acetate membrane at 30 min was 1.13 and 1.00 IU/cm² for insulin solution and fast-dissolving film, respectively, demonstrating to be similar. In conclusion, the use of HPβCD/poloxamer 188 is feasible for the development of sublingual insulin solutions/films.

How to characterize a nasal product. The state of the art of in vitro and ex vivo specific methods

Nasal delivery offers many benefits over other conventional routes of delivery (e.g. oral or intravenous administration). Benefits include, among others, a fast onset of action, non-invasiveness and direct access to the central nervous system. The nasal cavity is not only limited to local application (e.g. rhinosinusitis) but can also provide direct access to other sites in the body (e.g. the central nervous system or systemic circulation). However, both the anatomy and the physiology of the nose impose their own limitations, such as a small volume for delivery or rapid mucociliary clearance. To meet nasal-specific criteria, the formulator has to complete a plethora of tests, in vitro and ex vivo, to assess the efficacy and tolerance of a new drug-delivery system. Moreover, depending on the desired therapeutic effect, the delivery of the drug should target a specific pathway that could potentially be achieved through a modified release of this drug. Therefore, this review focuses on specific techniques that should be performed when a nasal formulation is developed. The review covers both the tests recommended by regulatory agencies (e.g. the Food and Drug Administration) and other complementary experiments frequently performed in the field.

Green carboxymethyl cellulose-silver complex versus cellulose origins in biological activity applications

This article deals with evaluating the role of cellulose origin, from wood and non-wood, on preparing green CMC-Ag complex as biological active agent. Viscose pulp as well as bagasse and rice straw pulps were used in preparation of CMCs, followed by complexation with AgNO_3. The complex structure (free-Ag, IR-spectra and TGA), morphology (TEM), antibiological and anti-tumor activities were studied. The data revealed that, the main interaction between CMC and silver is occurred via carboxylate groups and ether link of 1ry alcohol, with formation stable 5-membered ring structure. For the case of RS-based CMC-Ag complex the interaction between COO groups and silica included RS is also possible, via hydrogen bonds. These complexes have anti-biological especially towards gram positive bacteria (B.subtilis, NCID-3610), and uni- and multi cellular fungi. AgNPs from viscose (VCMC-Ag complex) has relatively higher anti-tumor activity for breast cancer MCF-7 in vitro than bagasse-based CMC-Ag complex (BCMC-Ag complex) with IC₅₀ 128μg/ml (as Ag). It is interesting to note that; viscose-based CMC-Ag complex (VCMC-Ag) has higher efficient behaviour as bioactive agent than literature reported agents, e.g., Pyridine derivative (∼300μg/ml).

Preparation of biocompatible magnetite-carboxymethyl cellulose nanocomposite: characterization of nanocomposite by FTIR, XRD, FESEM and TEM

The preparation and characterization of magnetite-carboxymethyl cellulose nano-composite (M-CMC) material is described. Magnetite nano-particles were synthesized by a modified co-precipitation method using ferrous chloride tetrahydrate and ferric chloride hexahydrate in ammonium hydroxide solution. The M-CMC nano-composite particles were synthesized by embedding the magnetite nanoparticles inside carboxymethyl cellulose (CMC) using a freshly prepared mixture of Fe3O4 with CMC precursor. Morphology, particle size, and structural properties of magnetite-carboxymethyl cellulose nano-composite was accomplished using X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR) and field emission scanning electron microscopy (FESEM) analysis. As a result, magnetite nano-particles with an average size of 35nm were obtained. The biocompatible Fe3O4-carboxymethyl cellulose nano-composite particles obtained from the natural CMC polymers have a potential range of application in biomedical field.

Bioavailability enhancement of verapamil HCl via intranasal chitosan microspheres

Chitosan microspheres are potential drug carriers for maximizing nasal residence time, circumventing rapid mucociliary clearance and enhancing nasal absorption. The aim of the present study was to develop and characterize chitosan mucoadhesive microspheres of verapamil hydrochloride (VRP) for intranasal delivery as an alternative to oral VRP which suffers low bioavailability (20%) due to extensive first pass effect. The microspheres were produced using a spray-drying and precipitation techniques and characterized for morphology (scanning electron microscopy), particle size (laser diffraction method), drug entrapment efficiency, thermal behavior (differential scanning calorimetry) and crystallinity (X-ray diffractometric studies) as well as in vitro drug release. Bioavailability of nasal VRP microspheres was studied in rabbits and the results were compared to those obtained after nasal, oral and intravenous administration of VRP solution. Results demonstrated that the microspheres were spherical with size 21-53 μm suitable for nasal deposition. The spray-drying technique was superior over precipitation technique in providing higher VRP entrapment efficiency and smaller burst release followed by a more sustained one over 6h. The bioavailability study demonstrated that the nasal microspheres exhibited a significantly higher bioavailability (58.6%) than nasal solution of VRP (47.8%) and oral VRP solution (13%). In conclusion, the chitosan-based nasal VRP microspheres are promising for enhancing VRP bioavailability by increasing the nasal residence time and avoiding the first-pass metabolism of the drug substance.

Nasal route: an alternative approach for antiemetic drug delivery

INTRODUCTION

Antiemetic drugs are used in the treatment of nausea and emesis. Development of novel delivery systems for antiemetic drugs, as an alternative to conventional preparations, is important in terms of good patient compliance and improving bioavailability. The nasal route offers unique superiorities, such as fast and high drug absorption, and high patient compliance. Therefore, a considerable amount of research has been carried out on the development of nasal delivery systems for antiemetic drugs.

AREAS COVERED

This review deals with the importance of nasal delivery of antiemetic drugs and the studies performed on this subject. The first part of this review summarizes the properties of the nasal route, its advantages and limitations, parameters affecting drug absorption through nasal mucosa, nasal passage pathways and general approaches to improve nasal transport. The second part reviews the studies conducted on the development of nasal delivery systems.

EXPERT OPINION

Due to its superiorities, the nasal route could be considered as an attractive alternative to oral and parenteral routes. To overcome the barrier properties of the nasal epithelium and to enhance transport of antiemetic drugs, several approaches, including permeation enhancers, in situ gel formulations and micro- and nanoparticulate systems, have been evaluated. The results obtained are promising and indicate that nasal formulations of some antiemetic drugs may enter the market in the near future.

Delivery of salmon calcitonin using a microneedle patch

Peptides and polypeptides have important pharmacological properties but only a limited number have been exploited as therapeutics because of problems related to their delivery. Most of these drugs require a parenteral delivery system which introduces the problems of pain, possible infection, and expertise required to carry out an injection. The aim of this study was to develop a transdermal patch containing microneedles (MNs) coated with a peptide drug, salmon calcitonin (sCT), as an alternative to traditional subcutaneous and nasal delivery routes. Quantitative analysis of sCT after coating and drying onto microneedles was performed with a validated HPLC method. In vivo studies were carried out on hairless rats and serum levels of sCT were determined by ELISA. The AUC value of MNs coated with a trehalose-containing formulation (250 ± 83 ng/mL min) was not significantly different as compared to subcutaneous injections (403 ± 253 ng/mL min), but approximately 13 times higher than nasal administration (18.4 ± 14.5 ng/mL min). T(max) (7.5 ± 5 min) values for MN mediated administration were 50% shorter than subcutaneous injections (15 min), possibly due to rapid sCT dissolution and absorption by dermal capillaries. These results suggest that with further optimization of coating formulations, microneedles may enable administration of sCT and other peptides without the need for hypodermic injections.

Comparison of the effect of topical and systemic melatonin administration on delayed wound healing in rats that underwent pinealectomy

OBJECTIVES

Melatonin is a hormone which has many systemic effects in addition to its strong antioxidant properties. The aim of the present study was to investigate the difference between sytemic and topical administration of melatonin by forming a chronic wound model in rats whose release of basal melatonin was supressed by pinealectomy.

MATERIAL AND METHODS

Experimental animals used in the study were divided into four equal groups: (i) a group of normal animals with wound formation (control), (ii) a group of animals who underwent pinelaectomy and wound formation (PINx), (iii) a group that underwent PINx + systemic melatonin administration, and (iv) a group that underwent PINx + topical melatonin administration. Fifteen days after pinealectomy, a bipediculed flap was formed on the back of the rats under anesthesia and then six excisional skin wounds were produced in all groups. Following the treatment that lasted 7 days, on day 8 the wound surface areas were measured and wound tissues were removed under anesthesia. In these tissues the levels of malondialdehit (MDA) and hydroxyproline (OH-proline) and the activities of superoxide dismutase(SOD) and glutathion peroxidase (GSH-Px) were measured.

RESULTS

In the PINx group, OH-prolin levels decreased significantly compared to the control group and wound surface areas increased. MDA levels increased compared to the control group, and SOD and GSH-Px decreased accordingly. Conversely, in two melatonin groups in which melatonin was administered systemically or topically MDA decreased while SOD ve GSH-Px enzymes increased.

CONCLUSION

In conclusion, in the present study it was shown that wound healing was prolonged in experimental animals deprived of melatonin through pinealectomy. Melatonin exerts positive effects on wound healing, whether it is administered topically or systemically.