Comparison of RPMI 2650 cell layers and excised sheep nasal epithelial tissues in terms of nasal drug delivery and immunocytochemistry properties

Cod liver oil nano-structured lipid carriers (Cod-NLCs) as a promising platform for nose to brain delivery: Preparation, in vitro optimization, ex vivo cytotoxicity & in vivo biodistribution utilizing radioiodinated zopiclone

“…(Cairo, Egypt). After creating a longitudinal excision in the lateral walls of the nose away from the septum to expose the nasal cavity, the nasal mucosa from the anterior and posterior sections was meticulously isolated from the sheep ( Gerber et al, 2022 ). Immediately after isolation the nasal mucosa was washed to remove any adhesive or connective tissues ( Gadhave et al, 2021 ), then immersed in ice-cold PBS pH 6.4 ( Nagaraja et al, 2021 ).…”

In vitro and ex vivo experimental models for evaluation of intranasal systemic drug delivery as well as direct nose‐to‐brain drug delivery

“…Specimens are taken prior to and after conducting permeation studies, whereafter the tissue samples are fixed in normal-buffered formalin (10%), dehydrated, embedded in wax, sliced with a microtome, rehydrated, stained, dehydrated, and evaluated under a microscope for physiological, anatomical and morphological features (Gerber et al, 2022).…”

“…A histology assay can evaluate the effect of mechanistic tissue damage that could potentially be inflicted during the excision and mounting of the epithelial tissue and/or to determine the potentially toxic effect of a drug or excipient on the tissue (Agu & Ugwoke, 2008). Specimens are taken prior to and after conducting permeation studies, whereafter the tissue samples are fixed in normal‐buffered formalin (10%), dehydrated, embedded in wax, sliced with a microtome, rehydrated, stained, dehydrated, and evaluated under a microscope for physiological, anatomical and morphological features (Gerber et al., 2022).…”

“…Gerber et al (2022) found that both RPMI 2650 cell line models and excised ovine respiratory tissue presented with similar permeation for a large molecular weight compound (fluorescein isothiocyanate [FITC]-dextran 4000 Da) and an efflux transporter substrate (Rhodamine 123). Similarities were also found with regard to immunohistochemistry properties, tight junction expression, and epithelial thickness.5 | EXPERIMENTAL CONSIDERATIONS DURING DRUG PERMEATION STUDIES TO DETERMINE INTRANASAL DRUG DELIVERYIn order to draw a correlation between in vitro or ex vivo and in vivoresults, and ultimately ensure that the model is of value to the drug development process, researchers should develop and adhere to standardized procedures with clear working parameters and F I G U R E 2 Correlation of the fractional absorption (FA) after IN administration to rats to the permeation of selected compounds across various cell lines, that is, (a) EpiAirway™, (b) MucilAir™, (c) Caco-2, (d) Calu-3, and (e) MDCK.…”

Formulation of Chitosan Microparticles for Enhanced Intranasal Macromolecular Compound Delivery: Factors That Influence Particle Size during Ionic Gelation

“…The knowledge obtained from this phase of the study was then implemented in the second phase of the study to produce two different fluorescein isothiocyanate dextran (FD-4) containing chitosan microparticles with distinctive target sizes (i.e., ±20 µm and ±200 µm) and to evaluate these delivery systems in terms of size, size distribution, FD-4 release, and FD-4 delivery across excised ovine nasal epithelial tissues. FD-4 has been widely used in several published studies [ 19 , 20 , 21 , 22 ] as a macromolecular compound that is representative of a group of macromolecular drugs, therefore making it an ideal macromolecular compound for the current study.…”