Search Results (192)

Transdermal drug delivery (TDD) is an increasingly important non-invasive method for administering active pharmaceutical ingredients (APIs) through the skin barrier, offering advantages such as improved therapeutic efficacy and reduced systemic side effects. As demand increases for patient-friendly and minimally invasive treatment options, TDD has attracted substantial attention in research and clinical practice. This review summarizes recent advances enhancing skin permeability through chemical enhancers (e.g., ethanol, fatty acids, terpenes), physical (e.g., iontophoresis, microneedles, sonophoresis), and nanotechnological methods (e.g., liposomes, ethosomes, solid lipid nanoparticles, and transferosomes). A comprehensive literature analysis, including scientific publications, regulatory guidelines, and patents, was conducted to identify innovative methods and materials used to overcome the barrier properties of the stratum corneum. Special emphasis was placed on in vitro, ex vivo, and in vivo evaluation techniques for such as Franz diffusion cells for assessing drug permeation and skin interactions. The findings highlight the importance of active physical methods, passive nanostructured systems, and chemical penetration enhancers. In conclusion, integrating multiple analytical techniques is essential for the rational design and optimization of effective transdermal drug delivery systems. Full article

Bedaquiline is known to shorten the duration of therapy of tuberculosis but has limitations, e.g., poor solubility and adverse effects such as prolongation of the QT interval. In this study, bedaquiline was incorporated into an inherently targeted nanosystem for improved permeation of the drug, with ex vivo diffusion studies performed to investigate its penetration. The bedaquiline-loaded mannan–chitosan oligosaccharide lactate nanoparticles were prepared by a one-step ionic gelation probe sonication method. A PermeGear 7-in-line flow-through diffusion system was used for the ex vivo diffusion studies across porcine and human pericardia. Bedaquiline-loaded nanoparticles with a particle size and potential of 192.4 nm and 40.5 mV, respectively, were obtained. The drug-loaded mannan–chitosan nanoparticles had an encapsulation efficacy of 98.7% and drug loading of 0.6%. Diffusion data indicated a steady-state flux of 2.889 and 2.346 µg.cm⁻².min⁻¹ for porcine and human pericardia, respectively. The apparent permeability coefficients were calculated to be 2.66 × 10⁻⁴ cm.min⁻¹ and 2.16 × 10⁻⁴ cm.min⁻¹ for porcine and human pericardia, respectively. The lag phases were 52.72 min and 0 min for porcine and human pericardia, respectively. The drug permeation indicated a consistent and linear diffusion pattern across both porcine and human pericardia, additionally approving the porcine pericardium as a great comparable tissue to human tissue for pericardial studies. This study is the first to demonstrate ex vivo diffusion of bedaquiline-loaded, macrophage-targeted chitosan–mannan nanoparticles across both human and porcine pericardia, representing a novel platform for disease-targeted, localized treatment of TB pericarditis. Full article

Pediatric high-grade gliomas (pHGGs), particularly diffuse midline gliomas (DMGs), are among the most lethal brain tumors due to poor survival and resistance to therapies. DMGs possess a distinct genetic profile, primarily driven by hallmark mutations such as H3K27M, ACVR1, and PDGFRA mutations/amplifications and TP53 inactivation, all of which contribute to tumor biology and therapeutic resistance. Developing physiologically relevant preclinical models that replicate both tumor biology and the tumor microenvironment (TME) is critical for advancing effective treatments. This review highlights recent progress in in vitro, ex vivo, and in vivo models, including patient-derived brain organoids, genetically engineered mouse models (GEMMs), and region-specific midline organoids incorporating SHH, BMP, and FGF2/8/19 signaling to model pontine gliomas. Key genetic alterations can now be introduced using lipofectamine-mediated transfection, PiggyBac plasmid systems, and CRISPR-Cas9, allowing the precise study of tumor initiation, progression, and therapy resistance. These models enable the investigation of TME interactions, including immune responses, neuronal infiltration, and therapeutic vulnerabilities. Future advancements involve developing immune-competent organoids, integrating vascularized networks, and applying multi-omics platforms like single-cell RNA sequencing and spatial transcriptomics to dissect tumor heterogeneity and lineage-specific vulnerabilities. These innovative approaches aim to enhance drug screening, identify new therapeutic targets, and accelerate personalized treatments for pediatric gliomas. Full article

Objectives: Ex vivo nasal mucosa models provide physiologically relevant platforms for evaluating nasal drug permeability; however, their application is often limited by high experimental variability and the absence of standardized methodologies. This study aimed to improve experimental design by addressing two major limitations: the confounding effects of mucosal thickness and the questionable reliability of fluorescein sodium (Flu-Na) as an integrity marker for chemically induced mucosal injury. Methods: Permeability experiments were conducted using porcine nasal tissues mounted in Franz diffusion cells, with melatonin and Flu-Na as model compounds. Tissues of varying thickness were collected from both intra- and inter-individual sources, and a numerical simulation-based method was employed to normalize apparent permeability coefficients (Papp) to a standardized mucosal thickness of 0.80 mm. The effects of thickness normalization and chemically induced damage were systematically evaluated. Results: Thickness normalization substantially reduced variability in melatonin Papp, particularly within same-animal comparisons, thereby improving statistical power and data reliability. In contrast, Flu-Na exhibited inconsistent correlations across different pigs and failed to reflect the expected increase in permeability following isopropyl alcohol (IPA)-induced epithelial damage. These results suggest that the relationship between epithelial injury and paracellular transport may be non-linear and not universally applicable under ex vivo conditions, limiting the suitability of Flu-Na as a standalone marker of mucosal integrity. Conclusions: The findings highlight the importance of integrating mucosal thickness correction into standardized experimental protocols and call for a critical reassessment of Flu-Na in nasal drug delivery research. Full article

Human skin provides an effective route of delivery for selected drugs. Topical penetration of molecules is largely attributed to passive diffusion, and the degree of penetration can be represented by in silico, in vitro, and ex vivo models. Percutaneous absorption of pharmaceutical ingredients is a delicate balance between the molecular properties of the drug, the skin properties of the patients, and the formulation properties. Understanding this interplay can aid in the development of products applied to the skin. The kinetics of percutaneous absorption and an understanding of the rate-limiting steps involved can facilitate the optimization of these systems and enhance the degree to which skin drug delivery can be achieved. Solute–vehicle, vehicle–skin, and solute–skin interactions contribute notably to product release as well as the rate of absorption and diffusion across skin layers. These interactions alter the degree of permeation by interfering with the skin barrier or solubility and thermodynamic activity of the active pharmaceutical ingredient. This article aims to provide a concise understanding of some of the factors involved in the skin absorption of topical products, i.e., the pharmacokinetics of percutaneous absorption as well as the solute–vehicle–skin interactions that determine the rate of release of products and the degree of drug diffusion across the skin. Full article

Objectives: In this study, Quality by Design (QbD) was used to develop an optimized self-nanoemulsifying drug delivery system (SNEDDS) as an ophthalmic formulation of flurbiprofen (FLU). Using a Box–Behnken design (BBD), an optimal SNEDDS composition was crafted, targeting enhanced corneal permeability and increased bioavailability of the drug. Methods: The levels of each factor(X) were established using a pseudo-ternary diagram, and the Box-Behnken design (BBD) was used to evaluate the components of oil (18.9 mg), surfactant (70.7 mg), and co-surfactant (10.0 mg) to optimize the SNEDDS formulation. The response(Y) considered were particle size, polydispersity index (PDI), transmittance, and stability. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to analyze the particle size and morphology. In vitro and ex vivo diffusion tests were conducted to assess drug flux and permeability. Result: Using a response optimization tool, the values of each X factor were optimized to achieve a small particle size (nm), a low polydispersity index (PDI), and high transmittance (%), resulting in a formulation prepared with 18.9 mg of oil, 70.7 mg of surfactant, and 10.0 mg of co-surfactant. The optimized SNEDDS exhibited a small particle size of 24.89 nm, a minimal PDI of 0.068, and a high transmittance of 74.85%. A transmission electron microscopy (TEM) analysis confirmed the presence of uniform spherical nanoemulsion droplets with an observed mean diameter of less than 25 nm, corroborating the dynamic light scattering (DLS) measurements. Furthermore, the SNEDDS demonstrated improved stability under the stress conditions of heating–cooling cycles, with no phase separation, creaming, or caking observed and no differences in its particle size, PDI, or transmittance. In vitro and ex vivo diffusion tests demonstrated that the flux of the optimized SNEDDS (2.723 ± 0.133 mg/cm², 5.446 ± 0.390 μg/cm²) was about 2.5 and 4 times higher than that of the drug dispersion, and the initial diffusion was faster, which is suitable for the characteristics of eye drops. Conclusions: Therefore, the formulation of a flurbiprofen-loaded SNEDDS (FLU-SNE) was successfully optimized using the QbD approach. The optimized FLU-SNE exhibited excellent stability and enhanced permeability, suggesting its potential effectiveness in treating various ocular inflammations, including uveitis and cystoid macular edema. Full article

Background: Conventional approaches in treating psoriasis demonstrate several complications. methotrexate (MTX) has been frequently used for its efficacy in managing moderate to severe psoriasis. However, MTX acts as an antagonist in regular dosage, which creates a patient compliance issue with undesirable consequences for patients, which necessitates development of an innovative approach to enhance skin permeation. Therefore, this study examines the improved topical administration of MTX utilizing a transferosome-loaded microneedle (MNs) array patch for the management of psoriasis. Methods: A design of experiment was used assess the effect of phospholipid content and edge activator type on vesicle size and entrapment efficiency (EE) to fabricate and optimize transferosome-loaded MTX. Furthermore, the MTX was incorporated within MNs and assessed for in vitro-ex vivo-in vivo parameters. Results: The morphology result revealed vesicles mean diameter of 169.4 ± 0.40 nm and EE of 69 ± 0.48 (%). Compared to traditional formulations (MTX patch and gel), the optimized transferosome-loaded dissolving MN array patch showed a substantial increase in diffusion of MTX tested over rat skin. Furthermore, an enhanced therapeutic benefit at the application site through cumulative drug release profiles suggested sustained release of MTX over 24 h. Moreover, in vivo experiments showed that the MN array patch exhibited higher accumulation, compared to conventional formulation tested. In addition, the plasma concentration measurements demonstrated a reduction in systemic exposure to MTX, diminishing the possibility of intricacy while preserving localized therapeutic efficacy. The capability of the MN array patch to lance the epidermal layers was proven by histological assessments. Conclusions: Thus, transferosome-loaded MNs is a viable method of delivering MTX topically with prolonged drug release and reduced systemic toxicity. Full article

Background and Objectives: Current guidelines recommend contrast-enhanced CT/MRI as confirmatory imaging tests for diagnosing hepatocellular carcinoma (HCC). However, these modalities are not always able to differentiate HCC from benign/dysplastic nodules that are commonly observed in cirrhotic livers. Consequently, many lesions require either pathological confirmation via invasive biopsy or surveillance imaging after 3–6 months, which results in delayed diagnosis and treatment. We aimed to develop noninvasive imaging biomarkers of liver cell size and cellularity, using magnetic resonance imaging (MRI), and to assess their utility in identifying HCC. Methods: MR cytometry combines measurements of water diffusion rates over different times corresponding to probing cellular microstructure at different spatial scales. Maps of microstructural properties, such as cell size and cellularity, are derived by fitting voxel values in multiple diffusion-weighted images to a three-compartment (blood, intra-, and extracellular water) model of the MRI signal. This method was validated in two phases: (1) histology-driven simulations, utilizing segmented histological images of different liver pathologies, and (2) ex vivo MR cytometry performed on fixed human liver specimens. Results: Both simulations and ex vivo MR cytometry of fixed human liver specimens demonstrated that HCC exhibits significantly smaller cell sizes and higher cellularities compared to normal liver and cirrhotic regenerative nodules. Conclusion: This study highlights the potential of MR cytometry to differentiate HCC from non-HCC lesions by quantifying cell size and cellularity in liver tissues. Our findings provide a strong foundation for further research into the role of MR cytometry in the noninvasive early diagnosis of HCC. Full article

Background: Folic acid (FA) is essential for cellular functions but has limited ocular bioavailability, restricting its therapeutic effectiveness. Objective: To develop chitosan (CS)-based nanogels (NGs) for FA transport and release, with corneal permeation evaluation. Methods: NGs’ hydrodynamic diameter (Ho) and polydispersity index (PdI) were determined using dynamic light scattering (DLS). CS-FA interaction was confirmed by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) was applied for the dehydrated material characterization. Scanning electron microscopy (SEM) was used to evaluate the NGs ultraestructure. In vitro drug release studies were performed using a modified Franz diffusion cell, and the release profile was fitted to obtain kinetics parameters. Mucoadhesion properties were evaluated through ζ-potential measurements. Ex vivo corneal permeation studies were conducted in rabbit corneas to compare the permeability of FA contained in NGs. Results: NGs presented a Ho of 312.4 ± 8.2 nm and a PdI of 0.28 ± 0.04. SEM imaging revealed spherical morphologies with minor variations in size and shape induced by FA. Lyophilized and resuspended NGs exhibited a 6.8% increase in Ho and a PdI rise to 0.42, indicating slight aggregation. In vitro drug release studies demonstrated sustained FA release, as determined by the Higuchi model. Mucoadhesion studies showed a decrease in ζ-potential from +36.9 to +18.1 mV, confirming electrostatic interactions with mucin. Ex vivo corneal permeation studies indicated that encapsulated FA permeated 2.6 times slower than free FA, suggesting sustained release. Conclusions: our findings demonstrate the potential of nanostructures in the form of NGs to enhance FA-loaded ocular delivery and bioavailability. Full article

The aim of this study was to prepare nanogels based on gelatin and xanthan-aldehyde for the enhancement of ibuprofen transdermal delivery. Firstly, the process of formulating nanogels using the reaction of Schiff’s base was optimized using experimental designs. Secondly, the structural characterization of nanogels was performed using laser particle size, zetometry, FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-Ray Diffraction), SEM (scanning electron microscopy), and thermogravimetric analysis. Finally, the evaluation of pharmacological characteristics and formulation therapeutic efficacy were achieved using in vitro dissolution kinetics, ex vivo transdermal diffusion studies, and an evaluation of in vivo anti-inflammatory activity. The results of the experimental plan show that the formulations containing a ratio of 15:10 ibuprofen/polymer and a ratio of 1:2 gelatin/xanthan-aldehyde with a gelling time of 2 h exhibited the best results; the formulations showed a mean diameter of 179.9 ± 6.2 nm, a polydispersity index of 0.193, which confirms monodispersed particles, a zeta potential of 24.7 mV, denoting a high degree of particle stability, and an encapsulation rate of 93.78%. The FTIR spectroscopy analysis showed the formation of imine function in the nanogel, and scanning electron microscopy showed the globular and porous form of the formulation. The incorporation of ibuprofen into nanogels improved their in vitro dissolution kinetics and ex vivo transdermal diffusion. The incorporation of nanogels into a patch system for its in vivo anti-inflammatory activity has shown excellent efficiency with a percentage of edema inhibition at a dose of 25 mg and 50 mg of 38.77 ± 1.6% and 82.03 ± 9.03%, respectively, while the commercial reference gel presented inhibition values at a dose of 25 mg and 50 mg of 10.61 ± 1.71% and 37.03 ± 11.43%, respectively. Thus, the innovative pharmaceutical form of ibuprofen offers a promising model for enhancing drug bioavailability and therapeutic effects while reducing adverse effects. Full article

Background/Objective: This study provided a comparison of the influence of each component of the microemulsion formulation and investigated the impact of varying concentrations of the microemulsion components on curcumin’s ability to penetrate the skin using an ex vivo porcine ear model. Methods: Curcumin microemulsions with different compositions were prepared and analyzed for their physicochemical properties. The dermal penetration efficacy of curcumin was evaluated from the different formulations and compared with non-microemulsion formulations. Results: Findings proved that microemulsion formulations improve the dermal penetration efficacy for curcumin when compared with non-microemulsion formulations. The composition of the microemulsion affects the penetration efficacy of curcumin and increases with decreasing oil content and increasing surfactant and water content. The best penetration for curcumin is achieved with a microemulsion that contained 7.7 g of medium-chain triglycerides as the oil phase, 6.92 g of Tween^® 80 and 62.28 g of ethanol as the surfactant mixture, and 23.1 g water. Conclusions: The present study provides a foundational basis for further development of different microemulsion formulations for enhancing the dermal penetration of poorly water-soluble active compounds. Full article

Tattoo inks contain varying amounts of metal nanoparticles (NPs) < 100 nm that, due to their unique physicochemical properties, may have specific biological uptake and cause skin or systemic toxicities. The toxic effects of certified reference standards of metal NPs and samples of commercially available tattoo inks were investigated using an in vitro system and a novel human ex vivo model. In vitro toxicity was evaluated using vitality assays on human skin cells (HaCaT cell line, primary fibroblasts, and keratinocytes). No toxicity was observed for Al₂O₃, Cr₂O₃, Fe₂O₃, and TiO₂ NPs, whereas CuO NPs showed dose-dependent toxicity on HaCaT and primary fibroblasts. Fibroblasts and keratinocytes were also sensitive to high concentrations of ZnO NPs. Reference standards and ink samples were then injected ex vivo into human skin explants using tattoo needles. Histological analysis showed pigment distribution deep in the dermis and close to dermal vessels, suggesting possible systemic diffusion. The presence of an inflammatory infiltrate was also observed. Immunohistochemical analysis showed increased apoptosis and expression of the inflammatory cytokine interleukin-8 in explants specifically tattooed with the reference standard or red ink. Taken together, the results suggest that the tattooing technique leads to exposure to toxic metal NPs and skin damage. Full article

Background/Objectives: Oral mucositis (OM) is a common and debilitating side effect of cancer therapy, characterized by ulceration or inflammation of the oral mucosa. This study evaluates the preclinical efficacy of curcumin-loaded bicosome systems (cur-BS) in mitigating chemotherapy-induced OM in mice. Methods: BS were prepared using a combination of 1,2-di-palmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), α-tocopherol, and curcumin, encapsulated within liposomal vesicles. Three formulations with different curcumin concentrations (180, 540, and 900 μM) were characterized by particle size, polydispersity index (PDI), encapsulation efficiency (EE), appearance, and morphology. The formulation with the highest concentration (cur-BS 5×) was selected for ex vivo permeability studies, release profile analysis, and in vitro anti-inflammatory efficacy. OM was induced in mice using 5-fluorouracil (5-FU) and acetic acid. Cur-BS 5× was compared to the commercial product Dentoxol^®. Results: The results showed that cur-BS 5× provided sustained release through a mechanism involving both diffusion and matrix relaxation, enhancing curcumin retention in deeper skin layers. Treatment with cur-BS 5× downregulated the expression of inflammatory markers (IL-1β and TNF-α). Macroscopic assessments demonstrated that both cur-BS 5× and Dentoxol^® reduced OM severity, with the greatest improvement observed between days 6 and 9. By day 24, OM scores were 1.25 ± 0.5 for cur-BS 5× and 1.0 ± 0.0 for Dentoxol^®, indicating effectiveness in both treatments. However, histological analysis revealed superior tissue recovery with cur-BS 5×, showing better epithelial structure and reduced inflammation. Cur-BS 5×-treated mice also exhibited greater weight recovery and higher survival rates compared to the Dentoxol^® group. Conclusions: These findings suggest that cur-BS 5× may enhance OM treatment, offering outcomes comparable to or better than those of Dentoxol^®. Full article

Background: An over-the-counter vasoconstrictive nasal solution with oxymetazoline (NS-OXY, 0.05%) has the potential to be used as a dental pulpal hemostatic medicament. A molecular engineering approach examined NS-OXY and its molecular constituent’s antimicrobial and blood biomass removal efficacy. Methods: An ex vivo cavity model was developed where standardized prepared teeth were exposed overnight to a model dentinal caries pathogen, S. mutans, and then exposed to sheep’s blood for 10 min, which simulated a pulpal exposure. Cavity preparations were rinsed with OXY (0.05%), benzalkonium chloride (BKC-0.025%), NS-OXY (with OXY-0.05% and BKC), ferric sulfate (20%;ViscoStat, FS), and distilled water (DI). For examining the bactericidal effect of NS-OXY, a disk diffusion antimicrobial assay was used where S. mutans was grown (20 h) on brain heart infusion (BHI) w/0.5% glucose agar plates and exposed to the treatment groups. Results: NS-OXY-treated samples had a lower residual bacterial or blood biomass than FS (p = 0.003). The diffusion test showed that NS-OXY, BKC, and FS had zones of inhibition greater than 10 mm, with NS-OXY having higher activity against S. mutans than FS (p = 0.0002), but lower than BKC (p = 0.0082). Conclusions: NS-OXY may be considered as a dental hemostatic agent after traumatic and carious pulpal exposure owing to NS-OXY’s antimicrobial and vasoconstrictive properties. Full article

Background/Objectives: Although multiple magnetic resonance imaging (MRI) indices are known to be sensitive to the noninvasive assessment of myelin integrity, their relative sensitivities have not been directly compared. This study aimed to identify the most sensitive MRI index for characterizing myelin composition in the spinal cord’s gray matter (GM) and white matter (WM). Methods: MRI was performed on a deer’s ex vivo cervical spinal cord. Quantitative indices known to be sensitive to myelin, including the myelin water fraction (MWF), magnetization transfer ratio (MTR), the signal ratio between T1- and T2-weighted images (T1W/T2W), fractional anisotropy (FA), mean diffusivity (MD), electrical conductivity (σ), and T1, T2, and T1ρ relaxation times were calculated. Their mean values were compared using repeated measures analysis of variance (ANOVA) and post hoc Bonferroni tests or Friedman and post hoc Wilcoxon tests to identify differences across GM and WM columns possessing distinct myelin distributions, as revealed by histological analysis. Relationships among the indices were examined using Spearman’s rank-order correlation analysis. Corrected p < 0.05 was considered statistically significant. Results: All indices except σ differed significantly between GM and all WM columns. Two of the three WM columns had significantly different MWF, FA, MD, and T2, whereas one WM column had significantly different MTR, σ, T1, and T1ρ from the others. A significant moderate to very strong correlation was observed among most indices. Conclusions: The sensitivity of MRI indices in distinguishing spinal cord regions varied. A strategic combination of two or more indices may allow the accurate differentiation of spinal cord regions. Full article