Evaluation of the Release Kinetics of a Pharmacologically Active Substance from Model Intra-Articular Implants Replacing the Cruciate Ligaments of the Knee

The Hitchhiker's Guide to Human Therapeutic Nanoparticle Development

Nanomedicine plays an essential role in developing new therapies through novel drug delivery systems, diagnostic and imaging systems, vaccine development, antibacterial tools, and high-throughput screening. One of the most promising drug delivery systems are nanoparticles, which can be designed with various compositions, sizes, shapes, and surface modifications. These nanosystems have improved therapeutic profiles, increased bioavailability, and reduced the toxicity of the product they carry. However, the clinical translation of nanomedicines requires a thorough understanding of their properties to avoid problems with the most questioned aspect of nanosystems: safety. The particular physicochemical properties of nano-drugs lead to the need for additional safety, quality, and efficacy testing. Consequently, challenges arise during the physicochemical characterization, the production process, in vitro characterization, in vivo characterization, and the clinical stages of development of these biopharmaceuticals. The lack of a specific regulatory framework for nanoformulations has caused significant gaps in the requirements needed to be successful during their approval, especially with tests that demonstrate their safety and efficacy. Researchers face many difficulties in establishing evidence to extrapolate results from one level of development to another, for example, from an in vitro demonstration phase to an in vivo demonstration phase. Additional guidance is required to cover the particularities of this type of product, as some challenges in the regulatory framework do not allow for an accurate assessment of NPs with sufficient evidence of clinical success. This work aims to identify current regulatory issues during the implementation of nanoparticle assays and describe the major challenges that researchers have faced when exposing a new formulation. We further reflect on the current regulatory standards required for the approval of these biopharmaceuticals and the requirements demanded by the regulatory agencies. Our work will provide helpful information to improve the success of nanomedicines by compiling the challenges described in the literature that support the development of this novel encapsulation system. We propose a step-by-step approach through the different stages of the development of nanoformulations, from their design to the clinical stage, exemplifying the different challenges and the measures taken by the regulatory agencies to respond to these challenges.

Characterizing the Drug-Release Enhancement Effect of Surfactants on Megestrol-Acetate-Loaded Granules

In this study, the effect of Cremophor® RH 40 (CR 40) classic micelles and Soluplus® (SP) polymeric micelles were investigated on a novel granule-type drug-delivery system containing megestrolacetate (MGA). Using a risk assessment-based approach on the formulation via melt technology resulted in the formation of these granules, presented as the dosage, with proper particle size and flow characteristics. Due to the application of a eutectic carrier base composition, gentle process conditions were reached, retaining the crystalline structure of the carrier system and allowing for the proper distribution of MGA in the granules. The increased water solubility (0.111 mg/mL to 2.154 mg/mL), and the decreased nano particle size (102.27 nm) with uniform distribution (polydispersity index of 0.259) and colloid stability (zeta potential of −12.99 mV) resulted in SP polymeric micelles prevailing over CR 40 micelles in this gastric dissolution study, performed in biorelevant fasted and fed state drug-release media. Mathematical characterization and kinetic model fitting supported the fast drug-release mechanism of polymeric micelles over micelles. The value-added polymeric micelle-containing formulation developed can be successfully administered perorally and the enhanced drug release offers the possibility of greater drug absorption in the gastrointestinal tract.

Chitosan Nanoparticle-Based System: A New Insight into the Promising Controlled Release System for Lung Cancer Treatment

Lung cancer has been recognized as one of the most often diagnosed and perhaps most lethal cancer diseases worldwide. Conventional chemotherapy for lung cancer-related diseases has bumped into various limitations and challenges, including non-targeted drug delivery, short drug retention period, low therapeutic efficacy, and multidrug resistance (MDR). Chitosan (CS), a natural polymer derived from deacetylation of chitin, and comprised of arbitrarily distributed β-(1-4)-linked d-glucosamine (deacetylated unit) and N-acetyl-d-glucosamine (acetylated unit) that exhibits magnificent characteristics, including being mucoadhesive, biodegradable, and biocompatible, has emerged as an essential element for the development of a nano-particulate delivery vehicle. Additionally, the flexibility of CS structure due to the free protonable amino groups in the CS backbone has made it easy for the modification and functionalization of CS to be developed into a nanoparticle system with high adaptability in lung cancer treatment. In this review, the current state of chitosan nanoparticle (CNP) systems, including the advantages, challenges, and opportunities, will be discussed, followed by drug release mechanisms and mathematical kinetic models. Subsequently, various modification routes of CNP for improved and enhanced therapeutic efficacy, as well as other restrictions of conventional drug administration for lung cancer treatment, are covered.

Chrysin-Loaded Microemulsion: Formulation Design, Evaluation and Antihyperalgesic Activity in Mice

Chrysin is a bioactive flavonoid found in pollens, passion flowers, honey, royal jelly, and propolis, which is commonly used as an ingredient in natural food supplements and is primarily responsible for their pharmacological properties. A transparent chrysin-loaded microemulsion (CS-ME) prepared through a ternary phase diagram was evaluated for use as an antihyperalgesic formulation. It was formulated with 40% Labrasol® (surfactant), 5% isopropyl myristate (oil phase) and 55% water (aqueous phase) and classified as an oil-in-water (O/W) microsized system (74.4 ± 15.8 nm). Its negative Zeta potential (−16.1 ± 1.9 mV) was confirmed by polarized light microscopy and dynamic light scattering analysis. In vitro studies in Franz-type static diffusion cells showed that chrysin release from CS-ME followed zero-order kinetics. Oral administration of CS-ME in mice resulted in a statistically significantly reduction (p < 0.05) in carrageenan-induced mechanical hyperalgesia compared to the control group. Treatment with CS-ME also showed anti-inflammatory activity by significantly decreasing the TNF-α level (p < 0.01) and increasing that of IL-10 (p < 0.05) compared to the control group. These results suggest that the proposed microsystem is a promising vector for the release of chrysin, being able to improve its capacity to modulate inflammatory and nociceptive responses.

Optimizing and Evaluating the Transdermal Permeation of Hydrocortisone Transfersomes Formulation Based on Digital Analysis of the In Vitro Drug Release and Ex Vivo Studies

BACKGROUND

Transfersomes can be used to enhance transdermal drug delivery due to their flexibility and ability to incorporate various molecules. For example, hydrocortisone (HC), a corticosteroid, is taken by different routes and serves as immunosuppressive, anticancer, and antiallergenic; however, it is poorly absorbed by the skin.

OBJECTIVE

Therefore, the current study suggested HC-loaded transfersomes as an alternative route of administration for reaching deeper skin layers or systemic circulation, to reduce the side effects of HC and improve its bioavailability.

METHODS

HC transfersomes were prepared by the thin-film hydration method and characterized for their vesicular size, zeta potential, drug entrapment efficiency, elasticity, FTIR spectroscopy, in vitro drug release, ex vivo permeation, and irritancy in rabbits. The optimized formulation, F15 (containing HC 20 mg, egg phosphatidylcholine (EPC) 400 mg, and 75 mg of Span 80), was chosen because it showed the highest (p< 0.05) EE% (60.4±0.80) and optimized sustained in vitro drug release (Q8 = 87.9±0.6%).

RESULTS

Extensive analysis of the drug release data from all formulas was performed using the DDSolver software which quantitatively confirmed the successful formulation. The Weibull equation was the best model to fit the release data compared to others, and the release mechanism was Fickian diffusion.

CONCLUSION

The simulated pharmacokinetic parameters showed that F15 had the highest AUC, MDT, and DE. Furthermore, F15 significantly enhanced HC permeation by 12-folds compared to the control through the excised rat's skin. The skin irritancy test has proven F15 safety and skin compatibility.

Stability and release mechanisms of double emulsions loaded with bioactive compounds; a critical review

Double emulsions (DEs), known as emulsions of emulsions, are dispersion systems in which the droplets of one dispersed liquid are further dispersed in another liquid, producing double-layered liquid droplets. These systems are widely used in the food and pharmaceutical industries due to their ability to co-encapsulate both hydrophilic and hydrophobic bioactive compounds. However, they are sensitive and unstable and their controlled release is challenging. In this study, first, the stability of DEs and their release mechanisms are reviewed. Then, the factors affecting their stability, and the release of bioactive compounds are studied. Finally, modeling of the release in DEs is discussed. This information can be useful to optimize the formulation of DEs in order to utilize them in different industries.

The Interactions and Release Kinetics of Sodium Hyaluronate Implemented in Nonionic and Anionic Polymeric Hydrogels, Studied by Immunoenzymatic ELISA Test

Hyaluronan is a natural polymer that was introduced to wound therapy. Formulations based on synthetic polymers such as methylcellulose (MC) and polyacrylic acid (PA) containing hyaluronan (HA) were proposed for the development of prospective wound-healing preparations. The formulations of different carrier concentrations containing a fixed amount of HA were prepared, and their viscosity was measured. The HA release was evaluated by employing the apparatus paddle over a disc. The hydrogels were introduced to the donor chamber, and HA was released to the pH = 7.4 buffer. The amount of HA released was obtained using the ELISA test. The release was analyzed on the basis of different kinetic models: zero-, first-, and second-order kinetics, as well as Higuchi and Korsmeyer-Peppas equations. The release rate constants and the half release time were calculated from these equations. According to the value of the coefficient of the determination, the best model describing the observed process was selected. The comparison between the dissolution profiles was carried out by calculating the difference factor f1 and the similarity factor f2. The interaction between the hydrogel components was investigated by Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) measurements. The study revealed that the zero-order equation best described the release of HA from the formulations studied. The FTIR research and the DSC study showed the intermolecular interaction between HA chains in MC-based compositions, as well as between HA and the synthetic polymer in the PA-based formulations. The study revealed that the formulation with a higher concentration of synthetic polymer may prolong the release of HA. The obtained results indicated that the proposed hydrogels have potential for wound healing and may accelerate skin regeneration.

Does skin permeation kinetics influence efficacy of topical dermal drug delivery system?: Assessment, prediction, utilization, and integration of chitosan biomacromolecule for augmenting topical dermal drug delivery in skin

Skin permeation is an integral part of penetration of topical therapeutics. Zero order in addition to Higuchi permeation kinetic is usually preferred in topical drug delivery cargo. Penetration of therapeutic entities through epidermal barrier is a major challenge for scientific fraternity. Furthermore, penetration of therapeutic entities determines the transportation and ultimately therapeutic efficacy of topical dermal dosage forms. Apart from experimentation models, mathematical equations, in silico docking, molecular dynamics (MDs), and artificial neural network (Neural) techniques are being used to assess free energies and prediction of electrostatic attractions in order to predict the permeation phenomena of therapeutic entities. Therefore, in the present review, we have summarized the significance of kinetic equations, in silico docking, MDs, and ANN in assessing and predicting the penetration behavior of topical therapeutics through dermal dosage form. In addition, the role of chitosan biomacromolecule in modulating permeation of topical therapeutics in skin has also been illustrated using computational techniques.

Description of Release Process of Doxorubicin from Modified Carbon Nanotubes

The article discusses the release process of doxorubicin hydrochloride (DOX) from multi-wall carbon nanotubes (MWCNTs). The studies described a probable mechanism of release and actions between the surface of functionalized MWCNTs and anticancer drugs. The surface of carbon nanotubes (CNTs) has been modified via treatment in nitric acid to optimize the adsorption and release process. The modification efficiency and physicochemical properties of the MWCNTs+DOX system were analyzed by using SEM, TEM, EDS, FTIR, Raman Spectroscopy and UV-Vis methods. Based on computer simulations at pH 7.4 and the experiment at pH 5.4, the kinetics and the mechanism of DOX release from MWNT were discussed. It has been experimentally observed that the acidic pH (5.4) is appropriate for the efficient release of the drug from CNTs. It was noted that under acidic pH conditions, which is typical for the tumour microenvironment almost 90% of the drug was released in a relatively short time. The kinetics models based on different mathematical functions were used to describe the release mechanism of drugs from MWCNTs. Our studies indicated that the best fit of experimental kinetic curves of release has been observed for the Power-law model and the fitted parameters suggest that the drug release mechanism of DOX from MWCNTs is controlled by Fickian diffusion. Molecular dynamics simulations, on the other hand, have shown that in a neutral pH solution, which is close to the blood pH, the release process does not occur keeping the aggregation level constant. The presented studies have shown that MWCNTs are promising carriers of anticancer drugs that, depending on the surface modification, can exhibit different adsorption mechanisms and release.

Multilevel Self-Healing Characteristics of Smart Polymeric Composite Coatings

Smart polymeric composite coatings demonstrating multilevel self-healing characteristics were developed and characterized. The pH-responsive smart carriers were synthesized by loading halloysite nanotubes (HNTs) with the benzotriazole corrosion inhibitor (BTA) using the vacuum cycling method, referred to as (BTA-loaded HNTs). Similarly, mechanically triggered melamine urea-formaldehyde microcapsules encapsulated with the boiled linseed oil-self-healing agent (LO) denoted as (MUFMCs) having an average size of a ∼120 μm diameter with a wall thickness of ∼1.84 μm were synthesized by the in situ polymerization technique. The newly designed double-layered smart polymeric composite coatings (DLPCs) were developed by mixing 3 wt % BTA-loaded HNTs with epoxy and applying it on the clean steel substrate to form a primer layer. After its complete curing, a top layer of epoxy containing 5 wt % of MUFMCs was deposited on it. For an exact comparison, single-layer polymeric composite coatings (SLPCs) containing 3 wt % BTA-loaded HNTs were also developed. The Fourier transform infrared radiation spectra of MUFMCs and BTA-loaded HNTs indicate the existence of all desired functional groups, confirming the presence of loaded chemical species such as LO and BTA into the smart carriers. Thermogravimetric analysis (TGA) indicates that ∼18% BTA is successfully loaded into HNTs. Quantitative UV-spectroscopic analysis indicates a pH-responsive release of BTA from BTA-loaded HNTs, which is time-dependent, attaining its maximum value of ∼ 90% in an acidic medium after 30 h. Electrochemical impedance spectroscopy analysis conducted in 3.5 wt % NaCl solution at room temperature for different immersion times reveals that SLPC exhibits the maximum charge-transfer resistance (R_ct) of 55.47 GΩ cm² after the 7th day of immersion, and then, a declining trend is observed, reaching 26.6 GΩ cm² after the 9th day. However, in the case of DLPC, the R_ct values show a continuous increment, attaining a maximum value of 82.11 GΩ cm² after the 9th day of immersion. The improved performance of DLPC can be ascribed to the efficient triggering of the individual carriers in the isolated matrices, resulting in the release of LO and BTA to form individual protective films at the damaged area due to the oxidative polymerization process and triazoles' ability of passive film formation on the substrate, respectively. The tempting self-healing properties of DLPCs justify their decent role for long-term corrosion protection in many industrial applications.

Vitamin D3/vitamin K2/magnesium-loaded polylactic acid/tricalcium phosphate/polycaprolactone composite nanofibers demonstrated osteoinductive effect by increasing Runx2 via Wnt/β-catenin pathway

Vitamin D₃, vitamin K₂, and Mg (10%, 1.25%, and 5%, w/w, respectively)-loaded PLA (12%, w/v) (TCP (5%, w/v))/PCL (12%, w/v) 1:1 (v/v) composite nanofibers (DKMF) were produced by electrospinning method (ES) and their osteoinductive effects were investigated in cell culture test. Neither pure nanofibers nor DKMF caused a significant cytotoxic effect in fibroblasts. The induction of the stem cell differentiation into osteogenic cells was observed in the cell culture with both DKMF and pure nanofibers, separately. Vitamin D_3, vitamin K₂, and magnesium demonstrated to support the osteogenic differentiation of mesenchymal stem cells by expressing Runx2, BMP2, and osteopontin and suppressing PPAR-γ and Sox9. Therefore, the Wnt/β-catenin signaling pathway was activated by DKMF. DKMF promoted large axonal sprouting and needle-like elongation of osteoblast cells and enhanced cellular functions such as migration, infiltration, proliferation, and differentiation after seven days of incubation using confocal laser scanning microscopy. The results showed that DKMF demonstrated sustained drug release for 144 h, tougher and stronger structure, higher tensile strength, increased water up-take capacity, decreased degradation ratio, and slightly lower Tm and Tg values compared to pure nanofibers. Consequently, DKMF is a promising treatment approach in bone tissue engineering due to its osteoinductive effects.

Manufacturing and Examination of Vaginal Drug Delivery System by FDM 3D Printing

Vaginal drug delivery systems can provide a long-term and constant liberation of the active pharmaceutical ingredient even for months. For our experiment, FDM 3D printing was used to manufacture the vaginal ring samples from thermoplastic polyurethane filament, which enables fast manufacturing of complex, personalized medications. 3D printing can be an excellent alternative instead of industrial manufacturing, which is complicated and time-consuming. In our work, the 3D printed vaginal rings were filled manually with jellified metronidazole or chloramphenicol for the treatment of bacterial vaginosis. The need for manual filling was certified by the thermogravimetric and heatflow assay results. The manufactured samples were analyzed by an Erweka USP type II Dissolution Apparatus, and the dissolution profile can be distinguished based on the applied jellifying agents and the API's. All samples were considered non-similar based on the pairwise comparison. The biocompatibility properties were determined by prolonged MTT assay on HeLa cells, and the polymer could be considered non-toxic. Based on the microbiological assay on E. coli metronidazole and chitosan containing samples had bactericidal effects while just metronidazole or just chitosan containing samples bacteriostatic effect. None of these samples showed a fungistatic or fungicide effect against C. albicans. Based on our results, we successfully manufactured 3D printed vaginal rings filled with jellified metronidazole.

Development and optimization of tibezonium iodide and lignocaine hydrochloride containing novel mucoadhesive buccal tablets: A pharmacokinetic investigation among healthy humans

OBJECTIVE

It is clinically important to deliver sustained-release mucoadhesive dosage of local anesthetic and antimicrobial agent for pain control. The current study aimed to develop and evaluate chitosan (CHI) based buccal mucoadhesive delivery for local release of tibezonium iodide (TBN) and lignocaine hydrochloride (LGN).

METHODS

Direct compression technique was employed, aided by other mucoadhesive polymers like hydroxypropylmethylcellulose (HPMC) and sodium alginate (SA) and evaluated for physicochemical and in vivo character.

RESULTS

Fourier transform infrared spectral analysis (FTIR), powdered X-ray diffraction (XRPD), and differential scanning calorimetry (DSC) absence of physical interaction between ingredients. The physical parameters complied with USP specifications for all formulations. Optimum swellability (551.9%) was offered from formulation TL15, containing 30% SA. Highest ex vivo mucoadhesive strength (24.79 g) and time (18.39 h) was found with TL8. Formulation TL8 also exhibited maximum in vivo residence time (11.37 h). Almost complete drug release at 6 h was possessed by formulation TL5 (HPMC and CHI, 20% each) for TBN (99.98%) and LGN (99.06%). The optimized formulation TL5 exhibited dosage stability up to 6 months at 75% relative humidity and retained drug contents. TL5 was well tolerated by the volunteers with no inflammation, pain or irritation found. Almost 73% of volunteers reported an increase in salivary secretion. The first-order salivary C_max of TBN and LGN were found as 16.02 and 7.80 µg/mL within 4 h, respectively.

CONCLUSION

Therefore, the sustained release mucoadhesive dosage form of TBN and LGN can be an effective and alternative option to conventional delivery.

Hyaluronic acid-coated chitosan nanoparticles as carrier for the enzyme/prodrug complex based on horseradish peroxidase/indole-3-acetic acid: Characterization and potential therapeutic for bladder cancer cells

Hybrid nanoparticles composed of different biopolymers for delivery of enzyme/prodrug systems are of interest for cancer therapy. Hyaluronic acid-coated chitosan nanoparticles (CS/HA NP) were prepared to encapsulate individually an enzyme/pro-drug complex based on horseradish peroxidase (HRP) and indole-3-acetic acid (IAA). CS/HA NP showed size around 158 nm and increase to 170 and 200 nm after IAA and HRP encapsulation, respectively. Nanoparticles showed positive zeta potential values (between +20.36 mV and +24.40 mV) and higher encapsulation efficiencies for both nanoparticles (up to 90 %) were obtained. Electron microscopy indicated the formation of spherical particles with smooth surface characteristic. Physicochemical and thermal characterizations suggest the encapsulation of HRP and IAA. Kinetic parameters for encapsulated HRP were similar to those of the free enzyme. IAA-CS/HA NP showed a bimodal release profile of IAA with a high initial release (72 %) followed by a slow-release pattern. The combination of HRP-CS/HA NP and IAA- CS/HA NP reduced by 88 % the cell viability of human bladder carcinoma cell line (T24) in the concentrations 0.5 mM of pro-drug and 1.2 μg/mL of the enzyme after 24 h.

Encapsulation of folic acid (vitamin B9) into sporopollenin microcapsules: Physico-chemical characterisation, in vitro controlled release and photoprotection study

Folic acid (FA) is a crucial vitamin for all living creatures. However, it is susceptible to degradation under pH, heat, ultraviolet (UV) and day sunlight conditions, resulting in lowering its bioavailability. Therefore, a versatile protective encapsulation system for FA is highly required to overcome its inherent instability. We report the use of the robust Lycopodium clavatum sporopollenin (LCS) microcapsules, extracted from their natural micrometer-sized raw spores, for FA microencapsulation. The physico-chemical characterisation of the LCS microcapsules are comprehensively investigated before and after the microencapsulation using SEM, elemental, CLSM, FTIR, TGA/DTG and XRD analyses, revealing a successful FA encapsulation within the LCS in an amorphous form. The phenylpropanoid acids, responsible for the UV protection and the autofluorescence of the LCS, were found in the LCS as evidenced by FTIR analysis. TGA/DTG results revealed that the hemi-cellulose and cellulose are the major component of the LCS. A controlled and sustained release of FA from FA-loaded LCS were achieved where the release profile of FA-loaded LCS was found to be pH-dependent. The percentages of cumulative FA released after 10 h at 37 ± 0.5 °C were 45.5% and 76.1% in pH 1.2 and 7.4, respectively, ensuring controlled and slow release in simulated physiological conditions. The FA release kinetic studies indicated the prevalence of the Fickian diffusion mechanism in pH 1.2, while anomalous non-Fickian transport was ascribed for FA release in pH 7.4. The in vitro cytotoxicity assay revealed that the obtained formulations were biocompatible against the human skin fibroblast (HSF) cell line. The versatile LCS microcapsules exhibited intriguing photostability for FA under UV or sunlight irradiation. Concretely, the obtained FA sustained delivery and photoprotection properties of these LCS microcapsules validate their multifunctional characteristics, opening up intriguing applications in oral and topical drug delivery as well as in food industry.

Sustained In Vitro and In Vivo Delivery of Metformin from Plant Pollen-Derived Composite Microcapsules

We developed a dual microencapsulation platform for the type 2 diabetes drug metformin (MTF), which is aimed to increase its bioavailability. We report the use of Lycopodium clavatum sporopollenin (LCS), derived from their natural spores, and raw Phoenix dactylifera L. (date palm) pollens (DPP) for MTF microencapsulation. MTF was loaded into LCS and DPP via a vacuum and a novel method of hydration-induced swelling. The loading capacity (LC) and encapsulation efficiency (EE) percentages for MTF-loaded LCS and MTF-loaded DPP microcapsules were 14.9% ± 0.7, 29.8 ± 0.8, and 15.2% ± 0.7, 30.3 ± 1.0, respectively. The release of MTF from MTF-loaded LCS microcapsules was additionally controlled by re-encapsulating the loaded microcapsules into calcium alginate (ALG) microbeads via ionotropic gelation, where the release of MTF was found to be significantly slower and pH-dependent. The pharmacokinetic parameters, obtained from the in vivo study, revealed that the relative bioavailability of the MTF-loaded LCS-ALG beads was 1.215 times higher compared to pure MTF, following oral administration of a single dose equivalent to 25 mg/kg body weight MTF to streptozotocin (STZ)-induced diabetic male Sprague-Dawley rats. Significant hypoglycemic effect was obtained for STZ-induced diabetic rats orally treated with MTF-loaded LCS-ALG beads compared to control diabetic rats. Over a period of 29 days, the STZ-induced diabetic rats treated with MTF-loaded LCS-ALG beads showed a decrease in the aspartate aminotransferase (AST), alanine aminotransferase (ALT), triglycerides, cholesterol, and low-density lipoprotein-cholesterol (LDL-C) levels, as well as an increase in glutathione peroxidase (GPx) and a recovery in the oxidative stress biomarker, lipid peroxidation (LPx). In addition, histopathological studies of liver, pancreas, kidney, and testes suggested that MTF-loaded LCS-ALG beads improved the degenerative changes in organs of diabetic rats. The LCS-ALG platform for dual encapsulation of MTF achieved sustained MTF delivery and enhancement of bioavailability, as well as the improved biochemical and histopathological characteristics in in vivo studies, opening many other intriguing applications in sustained drug delivery.

Green Synthesis of Thermo-Responsive Hydrogel from Oil Palm Empty Fruit Bunches Cellulose for Sustained Drug Delivery

Drug delivery is a difficult task in the field of dermal therapeutics, particularly in the treatment of burns, wounds, and skin diseases. Conventional drug delivery mediums have some limitations, including poor retention on skin/wound, inconvenience in administration, and uncontrolled drug release profile. Hydrogels able to absorb large amount of water and give a spontaneous response to stimuli imposed on them are an attractive solution to overcome the limitations of conventional drug delivery media. The objective of this study is to explore a green synthesis method for the development of thermo-responsive cellulose hydrogel using cellulose extracted from oil palm empty fruit bunches (OPEFB). A cold method was employed to prepare thermo-responsive cellulose hydrogels by incorporating OPEFB-extracted cellulose and Pluronic F127 (PF127) polymer. The performance of the synthesized thermo-responsive cellulose hydrogels were evaluated in terms of their swelling ratio, percentage of degradation, and in-vitro silver sulfadiazine (SSD) drug release. H8 thermo-responsive cellulose hydrogel with 20 w/v% PF127 and 3 w/v% OPEFB extracted cellulose content was the best formulation, given its high storage modulus and complex viscosity (81 kPa and 9.6 kPa.s, respectively), high swelling ratio (4.22 ± 0.70), and low degradation rate (31.3 ± 5.9%), in addition to high t50% value of 24 h in SSD in-vitro drug release to accomplish sustained drug release. The exploration of thermo-responsive cellulose hydrogel from OPEFB would promote cost-effective and sustainable drug delivery system with using abundantly available agricultural biomass.

Efficient drug delivery vehicles of environmentally benign nano-fibers comprising bioactive glass/chitosan/polyvinyl alcohol composites

Nano-fiber composites have shown promising potential in biomedical and biotechnological applications. Herein, novel nano-fiber composites constituting a blend of polyvinyl alcohol (PVA) and chitosan (CS) along with different weight ratios of nano-bioactive glass (BG) were prepared by electrospinning. Nano-fibers incorporating 10% (by wt.) of BG were uniform, dense and defect-free with a diameter of 20-125 nm. The model osteoporotic drug (Risedronate sodium) was blended with the electrospinning forming solution and the in-vitro drug release was further studied. About 30% of the drug was released after only 30 min and the release pattern was sustained over 96 h. Drug release took place through a two-stage intra-particle diffusion mechanism. BG-incorporated nano-fibers markedly retarded the drug release profile relative to their BG-free counterparts. They also enhanced the drug release efficiency by releasing 93 ± 4% of the drug. The developed nano-fiber composites can be potentially used as drug-delivery vehicles due to their efficiency and sustained drug release capacity.

Pharmacokinetics and Pharmacodynamics of Curcumin-Loaded Solid Lipid Nanoparticles in the Management of Streptozotocin-Induced Diabetes Mellitus: Application of Central Composite Design

Due to poor bioavailability and chemical instability, the effectiveness of curcumin is negligible in the treatment of numerous diseases. Solid lipid nanoparticles (SLNs) increase the bioavailability of lipophilic compounds and protect the drug from gastrointestinal degradation. The objective of our study is the utilization of SLNs to improve the pharmacokinetics and pharmacodynamics of curcumin in the management of diabetes mellitus. Central composite design was used to prepare curcumin-loaded SLNs (Cur-SLN). The analysis of independent variables like drug concentration, lipid concentration, and surfactant concentration was carried out using analysis of variance (ANOVA) to obtain the optimized batch (optimized Cur-SLN) having the desired values of dependent variables particle size and entrapment efficiency. In vitro release, differential scanning calorimeter (DSC), transmission electron microscopy (TEM), and Fourier Transform Infra-Red (FTIR) studies of optimized Cur-SLN were carried out and then its pharmacokinetic and pharmacodynamic studies were performed. The model was found to be significant for particle size and entrapment efficiency based on F-value and p-value. The optimized batch's predicted values were in close agreement with the actual values of particle size and entrapment efficiency. TEM results confirm mono-dispersion and spherical shape of particles in the formulation. The DSC results confirmed the changing of drug from crystalline to amorphous form. Burst release followed by the sustained release was obtained in the in vitro release studies. The pharmacokinetic study shows enhanced bioavailability of optimized Cur-SLN compared with a plain drug suspension. The optimized Cur-SLN achieved higher antidiabetic activity in streptozotocin-induced diabetes mellitus rats than the plain drug suspension. SLNs can be used as a promising technique for delivering curcumin in the management of diabetes mellitus.

Development of In Situ Gelling Meloxicam-Human Serum Albumin Nanoparticle Formulation for Nose-to-Brain Application

The aim of this study was to develop an intranasal in situ thermo-gelling meloxicam-human serum albumin (MEL-HSA) nanoparticulate formulation applying poloxamer 407 (P407), which can be administered in liquid state into the nostril, and to increase the resistance of the formulation against mucociliary clearance by sol-gel transition on the nasal mucosa, as well as to improve drug absorption. Nanoparticle characterization showed that formulations containing 12-15% w/w P407 met the requirements of intranasal administration. The Z-average (in the range of 180-304 nm), the narrow polydispersity index (PdI, from 0.193 to 0.328), the zeta potential (between -9.4 and -7.0 mV) and the hypotonic osmolality (200-278 mOsmol/L) of MEL-HSA nanoparticles predict enhanced drug absorption through the nasal mucosa. Based on the rheological, muco-adhesion, drug release and permeability studies, the 14% w/w P407 containing formulation (MEL-HSA-P14%) was considered as the optimized formulation, which allows enhanced permeability of MEL through blood-brain barrier-specific lipid fraction. Cell line studies showed no cell damage after 1-h treatment with MEL-HSA-P14% on RPMI 2650 human endothelial cells' moreover, enhanced permeation (four-fold) of MEL from MEL-HSA-P14% was observed in comparison to pure MEL. Overall, MEL-HSA-P14% can be promising for overcoming the challenges of nasal drug delivery.

Alginate sulfate-based hydrogel/nanofiber composite scaffold with controlled Kartogenin delivery for tissue engineering

In this study, we fabricated two different arrangements of laminated composite scaffolds based on Alginate:Alginate sulfate hydrogel, PCL:Gelatin electrospun mat, and Kartogenin-PLGA nanoparticles (KGN-NPs). The optimized composite scaffold revealed a range of advantages such as improved mechanical features as well as less potential of damage (less dissipated energy), interconnected pores of hydrogel and fiber with adequate pore size, excellent swelling ratio, and controlled biodegradability. Furthermore, the synthesized KGN-NPs with spherical morphology were incorporated into the composite scaffold and exhibited a linear and sustained release of KGN within 30 days with desirable initial burst reduction (12% vs. 20%). Additionally, the cytotoxicity impact of the composite was evaluated. Resazurin assay and Live/Dead staining revealed that the optimized composite scaffold has no cytotoxic effect and could improve cell growth. Overall, according to the enhanced mechanical features, suitable environment for cellular growth, and sustained drug release, the optimized scaffold would be a good candidate for tissue regeneration.

Formulation and Evaluation of Levofloxacin and Betamethasone Ophthalmic Emulgel

OBJECTIVE

Drug delivery to ocular tissues is challenging due to rapid removal of instilled drug due to low resident time in ocular tissues. The aim of the study was to formulate an ophthalmic emulgel that delivers two drugs (betamethasone sodium phosphate [BSP] and levofloxacin). The new combination will allow the simultaneous administration and extended release of the two drugs which potentially improve resident time in ocular tissues, patient compliance, and adherence to treatment.

MATERIALS AND METHODS

Formulations containing different gelling agents at different concentrations were prepared to choose the optimum combination regarding physical properties and release. The emulgel formulations F1, F2, F3, and F4 were made using gelling agent 1% and 2% xanthan gum, 1% carbopole 934, and 2% methyl cellulose, respectively. F5 was formulated using 2% methyl cellulose with double the amount of poloxamer 188 as emulsifying agent. All the formulations were examined regarding their physical appearance, pH, viscosity, drug content, and in vitro drug release. The optimum formula was also examined for antibacterial activity.

RESULTS

The results demonstrated that F5 was the optimum formulation having a proper physical characteristics and release profile of both drugs, 96% and 90% for BSP and levofloxacin, respectively, compared to other formulations and commercial eye drops.

CONCLUSION

Simultaneous and extended release of the two drugs was achieved using one formulation of emulgel. The ability to deliver hydrophilic and hydrophobic drug through the same formulation without the need to use two drops will improve patient compliance and hence patient adherence to treatment.

Controlled Release of Anti-Inflammatory and Proangiogenic Factors from Macroporous Scaffolds

The simultaneous local delivery of anti-inflammatory and proangiogenic agents via biomaterial scaffolds presents a promising method for improving the engraftment of tissue-engineered implants while avoiding potentially detrimental systemic delivery. In this study, polydimethylsiloxane (PDMS) microbeads were loaded with either anti-inflammatory dexamethasone (Dex) or proangiogenic 17β-estradiol (E2) and subsequently integrated into a single macroporous scaffold to create a controlled, dual-drug delivery platform. Compared to a standard monolithic drug dispersion scaffold, macroporous scaffolds containing drug-loaded microbeads exhibited reduced initial burst release and increased durability of drug release for both agents. The incubation of scaffolds with lipopolysaccharide (LPS)-stimulated M1 macrophages found that Dex suppressed the production of proinflammatory and proangiogenic factors when compared to drug-free control scaffolds; however, the coincubation of macrophages with Dex and E2 scaffolds restored their proangiogenic features. Following implantation, Dex-loaded microbead scaffolds (Dex-μBS) suppressed host cell infiltration and integration, when compared to controls. In contrast, the codelivery of dexamethasone with estrogen from the microbead scaffold (Dex+E2-μBS) dampened overall host cell infiltration, but restored graft vascularization. These results demonstrate the utility of a microbead scaffold approach for the controlled, tailored, and local release of multiple drugs from an open framework implant. It further highlights the complementary impacts of local Dex and E2 delivery to direct the healthy integration of implants, which has broad applications to the field of tissue engineering and regenerative medicine.

Synthesis and Characterization of Chitosan-Based Nanodelivery Systems to Enhance the Anticancer Effect of Sorafenib Drug in Hepatocellular Carcinoma and Colorectal Adenocarcinoma Cells

The formation of two nanodelivery systems, Sorafenib (SF)-loaded chitosan (SF-CS) and their folate-coated (SF-CS-FA) nanoparticles (NPs), were developed to enhance SF drug delivery on human Hepatocellular Carcinoma (HepG2) and Colorectal Adenocarcinoma (HT29) cell lines. The ionic gelation method was adopted to synthesize the NPs. The characterizations were performed by DLS, FESEM, TEM, XRD, TGA, FTIR, and UV-visible spectroscopy. It was found that 83.7 ± 2.4% and 87.9 ± 1.1% of encapsulation efficiency; 18.2 ± 1.3% and 19.9 ± 1.4% of loading content; 76.3 ± 13.7 nm and 81.6 ± 12.9 nm of hydrodynamic size; 60–80 nm and 70–100 nm of TEM; and FESEM sizes of near-spherical shape were observed, respectively, for SF-CS and SF-CS-FA nanoparticles. The SF showed excellent release from the nanoparticles under pH 4.8 PBS solution, indicating a good delivery system for tumor cells. The cytotoxicity study revealed their better anticancer action towards HepG2 and HT29 cell lines compared to the free sorafenib. Moreover, both NPs systems showed negligible toxicity to normal Human Dermal Fibroblast adult cells (HDFa). This is towards an enhanced anticancer drug delivery system with sustained-release properties for better cancer management.

Radiolabeled Tedizolid Phosphate Liposomes for Topical Application: Design, Characterization, and Evaluation of Cellular Binding Capacity

Nowadays, the incidence of acute bacterial skin and skin structure infection (ABSSSI) is increasing. The increased bioavailability and reduced drug resistance of antibiotics are crucial to obtain a more effective treatment response in these infections. These favorable properties could be achieved by different drug delivery systems such as liposomes. In this study, nanosized, radiolabeled tedizolid phosphate liposomal formulations were prepared and evaluated with their in vitro cellular binding capacity and biocompatible profile for topical treatment of ABSSSI. Liposomes were characterized by evaluation of their visual inspection, particle size (about 190-270 nm), zeta potential value (around 0), and encapsulation efficiency (nearly 10%). The release rate of tedizolid phosphate from liposomes was also studied using dialysis membranes and evaluated kinetically. The stability of formulations was observed at three different temperatures and humidity conditions for 28 days. Afterward, liposomes were labeled with ^99mTc, and the optimal amount of reducing agent (stannous chloride) was determined as 500 μg in this direct labeling procedure. All liposome formulations were successfully radiolabeled with high efficiency and exhibited high radiochemical purity (> 80%) during 6 h in different media. Furthermore, the cellular bindings of liposomal formulations were evaluated in human skin fibroblast cells by measuring the radioactivity. Higher radioactivity values were obtained in CCD-1070Sk cells incubated by liposome formulations compared to sodium pertechnetate. This finding suggested that liposomal formulation increased the cellular binding of radioactivity. By the result of our study, nanosized, tedizolid phosphate encapsulated liposome formulation was found to be a favorable carrier system in the treatment of ABSSSI.

Preparation of solid dispersion systems for enhanced dissolution of poorly water soluble diacerein: In-vitro evaluation, optimization and physiologically based pharmacokinetic modeling

Diacerein (DCN), a BCS II compound, suffers from poor aqueous solubility and limited bioavailability. Solid dispersion systems (SD) of DCN were prepared by solvent evaporation, using hydrophilic polymers. In-vitro dissolution studies were performed and dissolution parameters were evaluated. I-Optimal factorial design was employed to study the effect of formulation variables (drug:polymer ratio and polymer type) on the measured responses including; drug content (DC) (%), dissolution efficiency at 15 min (DE _{(15 min)}%) and 60 min (DE _{(60 min)}%) and mean dissolution time (MDT) (min). The optimized SD was selected, prepared and evaluated, allowing 10.83 and 3.42 fold increase in DE _{(15 min)}%, DE _{(60 min)}%, respectively and 6.07 decrease in MDT, compared to plain drug. DSC, XRD analysis and SEM micrographs confirmed complete amorphization of DCN within the optimized SD. Physiologically based pharmacokinetic (PBPK) modeling was employed to predict PK parameters of DCN in middle aged healthy adults and geriatrics. Simcyp^® software established in-vivo plasma concentration time curves of the optimized SD, compared to plain DCN. Relative bioavailability of the optimized SD compared to plain drug was 229.52% and 262.02% in healthy adults and geriatrics, respectively. Our study reports the utility of PBPK modeling for formulation development of BCS II APIs, via predicting their oral bio-performance.

How Molecular Mobility, Physical State, and Drug Distribution Influence the Naproxen Release Profile from Different Mesoporous Silica Matrices

Aiming to evaluate how the release profile of naproxen (nap) is influenced by its physical state, molecular mobility, and distribution in the host, this pharmaceutical drug was loaded in three different mesoporous silicas differing in their architecture and surface composition. Unmodified and partially silylated MCM-41 matrices, respectively MCM-41 and MCM-41_sil, and a biphenylene-bridged periodic mesoporous organic matrix, PMO_Bph, were synthetized and used as drug carriers, having comparable pore sizes (∼3 nm) and loading percentages (∼30% w/w). The loaded guest was investigated by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, powder X-ray diffraction (XRD), differential scanning calorimetry (DSC), and dielectric relaxation spectroscopy (DRS). DSC and XRD confirmed amorphization of a nap fraction incorporated inside the pores. A narrower glass transition was detected for PMO_Bph_nap, taken as an indication of the impact of host ordering, which also hinders the guest molecular mobility inside the pores as probed by DRS. While the PMO_Bph matrix is highly hydrophobic, the unmodified MCM-41 readily adsorbs water, accelerating the nap relaxation rate in the respective composite. In the dehydrated state, the faster dynamics was found for the silylated matrix since guest-host hydrogen bond interactions were inhibited to some extent by methylation. Nevertheless, in all the prepared composites, bulk-like crystalline drug deposits outside pores in a greater extent in PMO_Bph_nap. The DRS measurements analyzed in terms of conductivity show that, upon melting, nap easily migrates into pores in MCM-41-based composites, while it stays in the outer surface in the ordered PMO_Bph, determining a faster nap delivery from the latter matrix. On the other side, the mobility enhancement in the hydrated state controls the drug delivery in the unmodified MCM-41 matrix vs the silylated one. Therefore, DRS proved to be a suitable technique to disclose the influence of the ordering of the host surface and its chemical modification on the guest behavior, and, through conductivity depletion, it provides a mean to monitor the guest entrance inside the pores, easily followed even by untrained spectroscopists.

Development of Water-Soluble Electrospun Fibers for the Oral Delivery of Cannabinoids

Cannabidiol (CBD) and cannabigerol (CBG) are two active pharmaceutical ingredients, derived from cannabis plant. In the present study, CBD and CBG were formulated with polyvinyl(pyrrolidone) (PVP) and Eudragit L-100, using electrohydrodynamic atomization (electrospinning). The produced fibers were smooth and uniform in shape, with average fiber diameters in the range of 700-900 nm for PVP fibers and 1-5 μm for Eudragit L-100 fibers. The encapsulation efficiency for both CB and CBG was high (over 90%) for all formulations tested. Both in vitro release and disintegration tests of the formulations in simulated gastric fluids (SGF) and simulated intestinal fluids (SIF) indicated the rapid disintegration and dissolution of the fibers and the subsequent rapid release of the drugs. The study concluded that the electrospinning process is a fast and efficient method to produce drug-loaded fibers suitable for the per os administration of cannabinoids.

Synthesis of resilient hybrid hydrogels using UiO-66 MOFs and alginate (hydroMOFs) and their effect on mechanical and matter transport properties

Herein, we report the preparation of an organic-inorganic hybrid hydrogel architecture using vinyl alginate and UiO-66 MOFs (metal-organic frameworks) modified with acrylic acid (AA) UiO-66AA. UiO-66 MOFs with different crystal sizes (600, 1500, and 2500 nm) were synthesized and the effect on the mechanical and transport properties of the resulting materials, such as water absorption capacity and drug release, were evaluated. HydroMOF showed higher water absorption capacity than the pure hydrogel and enhanced mechanical properties, which depend on crystal size and the amount of UiO-66AA MOF used. The initial release rate of drug (burst release) from hydroMOFs was lower when small-sized crystals or a small amount of large-sized crystals were used; thus these are essential in changing half-life values of release rates. Finally, the cytotoxicity screening successfully showed that hydroMOFs are promising biocompatible compounds proven to have the advantages of minimized burst release and mechanical robustness.

The strategies for the modelling of the passive mass transport through porous membranes: Applicability to transdermal delivery systems

The paper concerns the modelling of the passive solute transport through porous membranes. A general scheme for the mass transport has been developed upon the mixed diffusion-advection-reaction model. The passive advection has been introduced as a certain simplification of the Navier-Stokes problem, involving a pressure gradient-induced creeping flow of an incompressible Newtonian fluid. Nine scenarios for the drug transport process have been tested versus two experimental datasets acquired earlier (photoacoustic depth-profiling and contact angle surface wettability techniques) for the characterization of bulk and interfacial processes in a model pharmaceutical system: the synthetic dodecanol-collodion porous membrane in contact with a photodegradable pigment dithranol. The scenarios considered include three mass transport models (the diffusion-advection-reaction, diffusion-advection and diffusion-reaction models) under three distinct types of the lower (the donor/acceptor interface) boundary conditions: the Dirichlet-type instantaneous source, the Dirichlet-type interface relaxation, and the Neumann-type concentration gradient. The results obtained indicate a considerable agreement between the experimental data and predictions of the diffusion-reaction and the general models for long times, however, some deviations were exhibited at the initial stages of the permeation process. It is considered, that the discrepancies originate from a specific penetrant behaviour at the interfaces, which violates boundary transfer schemes classically employed for the mass transport phenomena quantification. Moreover, an additional mixing process taking place close to the interface related to the liquid flow driven by the surface tension gradients (so-called classic and thermal Marangoni effect) could play a still underestimated role in the trans-interfacial mass transport.

Tadalafil-Loaded Limonene-Based Orodispersible Tablets: Formulation, in vitro Characterization and in vivo Appraisal of Gastroprotective Activity

Background

Gastric ulcer is a prevalent disease with various etiologies, including non-steroidal anti-inflammatory drugs and alcohol consumption. This study aimed to explore the dual gastric protection effect of tadalafil and limonene as a self-nanoemulsifying system (SNES)-based orodispersible tablets.

Methods

Tadalafil-loaded limonene-based SNES was prepared, and the optimum formula was characterized in terms of particle size (PS), polydispersity index (PDI), and zeta potential (ZP) then loaded on various porous carriers to formulate lyophilized orodispersible tablets (ODTs). The ODTs were evaluated via determining hardness, friability, content uniformity, wetting, and disintegration time. The selected ODT was examined for its gastric ulcer protective effect against alcohol-induced ulcers in rat model. Ulcer score and ulcer index were computed for rats stomachs that were inspected macroscopically and histopathologically.

Results

The prepared SNES had droplet size of 104 nm, polydispersity index of 0.2, and zeta potential of −15.4 mV. From the different ODTs formulated, the formula with superior wetting time: 23.67 s, outstanding disintegration time: 28 s, accepted hardness value: 3.11 kg/cm² and friability: 0.6% was designated. A significant gastroprotective effect of the unloaded and tadalafil-loaded ODTs was recognized compared to the omeprazole pre-treated group. Moreover, the histopathological analysis displayed very mild inflammation in the limonene-based ODTs group and intact structure in the tadalafil-loaded pre-treated animals.

Conclusion

Limonene gastroprotective effect functioned along with tadalafil in the form of SNES-incorporated ODTs could serve as a promising revenue for better efficacy in gastric ulcer prevention.

In Vitro Tests of FDM 3D-Printed Diclofenac Sodium-Containing Implants

One of the most promising emerging innovations in personalized medication is based on 3D printing technology. For use as authorized medications, 3D-printed products require different in vitro tests, including dissolution and biocompatibility investigations. Our objective was to manufacture implantable drug delivery systems using fused deposition modeling, and in vitro tests were performed for the assessment of these products. Polylactic acid, antibacterial polylactic acid, polyethylene terephthalate glycol, and poly(methyl methacrylate) filaments were selected, and samples with 16, 19, or 22 mm diameters and 0%, 5%, 10%, or 15% infill percentages were produced. The dissolution test was performed by a USP dissolution apparatus 1. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide dye (MTT)-based prolonged cytotoxicity test was performed on Caco-2 cells to certify the cytocompatibility properties. The implantable drug delivery systems were characterized by thermogravimetric and heatflow assay, contact angle measurement, scanning electron microscopy, microcomputed tomography, and Raman spectroscopy. Based on our results, it can be stated that the samples are considered nontoxic. The dissolution profiles are influenced by the material properties of the polymers, the diameter, and the infill percentage. Our results confirm the potential of fused deposition modeling (FDM) 3D printing for the manufacturing of different implantable drug delivery systems in personalized medicine and may be applied during surgical interventions.

An Injectable Hydrogel Scaffold With Kartogenin-Encapsulated Nanoparticles for Porcine Cartilage Regeneration: A 12-Month Follow-up Study

BACKGROUND

Treatment of cartilage lesions is clinically challenging. A previous study demonstrated that a hyaluronic acid hydrogel (m-HA) with kartogenin (KGN)-loaded PLGA nanoparticles (m-HA+KGN treatment) achieved superior cartilage repair in a rabbit model. However, large animals serve as a bridge to translate animal outcomes into the clinic.

HYPOTHESES

(1) m-HA+KGN treatment could facilitate hyaline cartilage and subchondral bone tissue repair in a porcine model. (2) Defect size and type (full-thickness chondral vs osteochondral) influence the therapeutic efficacy of m-HA+KGN treatment.

STUDY DESIGN

Controlled laboratory study.

METHODS

48 minipigs were randomized into 3 treatment groups: m-HA hydrogel with KGN-loaded PLGA nanoparticles (m-HA+KGN treatment), m-HA hydrogel (m-HA treatment), and untreated (blank treatment). Full-thickness chondral (6.5 mm or 8.5 mm in diameter) or osteochondral (6.5 mm or 8.5 mm in diameter; 5-mm depth) defects were prepared in the medial femoral condyle. At 6 and 12 months postoperatively, defect repair was assessed by macroscopic appearance, magnetic resonance imaging (MRI), micro-computed tomography (µCT), and histologic and biomechanical tests.

RESULTS

The m-HA+KGN group exhibited superior gross and histological healing after evaluation at 6 and 12 months postoperatively. Improved quality of the repaired cartilage demonstrated by MRI and better subchondral bone reconstruction assessed by µCT were observed in the m-HA+KGN group. The m-HA+KGN group showed more hyaline-like cartilage exhibited by histological staining in terms of extracellular matrix, cartilage lacuna, and type II collagen. The biomechanical properties were improved in the m-HA+KGN group. With m-HA+KGN treatment, defects with a diameter of 6.5 mm or full-thickness chondral-type defects possessed significantly higher ICRS macroscopic and histological scores compared with diameter 8.5 mm or osteochondral-type defects.

CONCLUSION

(1) m-HA+KGN treatment facilitated hyaline cartilage and subchondral bone tissue repair in a porcine model at the 12-month follow-up. (2) m-HA+KGN treatment demonstrated better therapeutic efficacy in defects with a diameter of 6.5 mm or full-thickness chondral-type defects.

CLINICAL RELEVANCE

This study verified the efficacy of this innovative KGN release system on cartilage repair. The KGN release system can be injected into defect sites arthroscopically. This convenient and minimally invasive operation holds important prospects for clinical application.

Curcumin-Loaded Nanoemulsion for Better Cellular Permeation

Curcumin nanoemulsion was prepared using coconut oil, Tween 80 (surfactant) and polyethylene glycol (co-solvent) with the addition of honey and glycerol as additives. The nanoemulsion was optimized and systematically characterized for transdermal delivery. Small particle size (15.92 nm), low polydispersity index (0.17) and slight acidic (pH 4.18) curcumin nanoemulsion was obtained without any chemical degradation based on the Fourier transform infrared (FTIR) spectrum. The incorporation of curcumin inside nanoglobul improved curcumin stability and skin permeability. Its high permeability can be seen from Nile dyed curcumin in different layers of skin through fluorescent imaging. The release kinetic of curcumin followed the Higuchi model, which explains why the skin permeation was a Fickian diffusion-controlled process because the Korsmeyer constant was proven to be 0.3 (<0.5). Nanoencapsulation slightly decreased the antioxidant capacity of curcumin for about 7.9% compared to its free counterpart. It showed low cytotoxicity (EC50 2.3552 µg/mL) to human skin fibroblasts. Cell death was noticed at a high concentration (2.5 µg/mL) of treatment. Curcumin was also found to promote wound closure at low concentration 0.1563 µg/mL and was comparable with the performance of ascorbic acid based on scratch assay. Therefore, this nutritious curcumin nanoemulsion is a promising transdermal delivery system for topical application.

Development and characterization of ethyl cellulose nanosponges for sustained release of brigatinib for the treatment of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) contributes to about 85% of lung cancer. By 2040, lung cancer cases estimated to rise to 3.6 million globally. Brigatinib (BG) acts as tyrosine kinase inhibitors that target the epidermal growth factor receptor of the epithelial lung cancer cells. BG loaded nanosponges (NSs) were prepared by the emulsion solvent evaporation technique using ethylcellulose (EC) and polyvinyl alcohol (PVA) as a stabilizer. Eight formulations were developed by varying the concentration of the drug (BG), EC and PVA followed by optimization through particle characterization; size, polydispersity index (PDI), zeta potential (ZP), drug entrapment and loading efficiency. The optimized formulation BGNS5 showed particles size (261.0 ± 3.5 nm), PDI (0.301) and ZP(−19.83 ± 0.06 Mv) together with entrapment efficiency (85.69 ± 0.04%) and drug loading (17.69 ± 0.01%). FTIR, DSC, XRD, and SEM showed drug-polymer compatibility, entrapment of drug in EC core, non-crystallinity of BG in NS and confirm spherical porous nature of the NS. BGNS5 reflects drug release in a sustained manner, 86.91 ± 2.12% for about 12 h. BGNS5 significantly decreased the cell viability of A549 human lung cancer cell lines with less hemolytic ratio compared to pure drug BG and EC. Based on the aforementioned results BGNS5 could be used in the effective treatment of NSCLC.

Development of 3D-Printed Layered PLGA Films for Drug Delivery and Evaluation of Drug Release Behaviors

3D printing has been widely used to rapidly manufacture a variety of solid dosage forms on-demand, without sacrificing precision. This study used extrusion-based 3D printing to prepare single-layered, tri-layered, and core-in-shell poly(lactic-co-glycolic acid) (PLGA) films carrying paclitaxel and rapamycin in combination or lidocaine alone. Each layer was composed of either low molecular weight (MW) PLGA or high MW PLGA. In vitro drug release kinetics of paclitaxel, rapamycin, and lidocaine for PLGA films were assessed and compared with PLGA-polyethylene glycol (PEG)-PLGA hydrogel discs. Regardless of the structure of PLGA film, paclitaxel (half-time: 54-63 days) was released faster than when compared with rapamycin (half-time: 74-80 days). In contrast, single-layered PLGA-PEG-PLGA discs released rapamycin (half-time 5.7 h) at a more rapid rate than paclitaxel (half-time: 7.3 h). Single-layered PLGA-PEG-PLGA discs enabled a faster drug release than PLGA films, noting that the disc matrices dissolve in water in 24 h. Similarly, lidocaine incorporated in PLGA films (half-time: 13-36 days) exhibited slower release patterns than that in PLGA-PEG-PLGA discs (half-time: 2.6 h). In vitro drug release patterns were explained using molecular models that simulate drug-polymer interactions. Analysis of models suggested that drug-polymer interactions, location of each drug in the polymeric matrix, and solubility of drugs in water were major factors that determine drug release behaviors from the polymeric films and discs.

Pharmacokinetic and Pharmacodynamic Evaluation of Resveratrol Loaded Cationic Liposomes for Targeting Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. The destructive nature of the disease makes it difficult for clinicians to manage the condition. Hence, there is an urgent need to find new alternatives for HCC, as the role of conventional cytotoxic drugs has reached a plateau to control HCC associated mortality. Antioxidant compounds of plant origin with potential anti-tumor effect have been recognized as alternate modes in cancer treatment and chemoprevention. Resveratrol (RS) is a model natural nonflavonoid drug known for its anti-cancer activity. However, its clinical application is limited due to its poor bioavailability. The current research work aims to formulate, optimize, and characterize RS loaded cationic liposomes (RLs) for specific delivery in HCC. The optimized liposomes formulation (RL5) was spherical with a vesicle size (VS) of 145.78 ± 9.9 nm, ζ potential (ZP) of 38.03 ± 9.12 mV, and encapsulation efficiency (EE) of 78.14 ± 8.04%. In vitro cytotoxicity studies in HepG2 cells demonstrated an improved anti-cancer activity of RL5 in comparison with free RS. These outcomes were supported by a cell uptake study in HepG2 cells, in which RL5 exhibited a higher uptake than free RS. Furthermore, confocal images of HepG2 cells after 3 and 5 h of incubation showed higher internalization of coumarin 6 (C6) loaded liposomes (CL) as compared to those of the free C6. Pharmacokinetic and pharmacodynamic (prophylactic and therapeutic treatment modalities) studies were performed in N-nitrosodiethylamine (NDEA-carcinogen) induced HCC in rats. Pharmacokinetic evaluation of RL5 demonstrated increased localization of RS in cancerous liver tissues by 3.2- and 2.2-fold increase in AUC and Cmax, respectively, when compared to those of the free RS group. A pharmacodynamic investigation revealed a significant reduction in hepatocyte nodules in RL5 treated animals when compared to those of free RS. Further, on treatment with RL5, HCC-bearing rats showed a significant decrease in the liver marker enzymes (alanine transaminase, alkaline phosphatase, aspartate transaminase, total bilirubin levels, γ-glutamyl transpeptidase, and α-fetoprotein), in comparison with that of the disease control group. Our findings were supported by histopathological analysis, and we were first to demonstrate that NDEA induced detrimental effect on rat livers was successfully reversed with the treatment of RL5 formulation. These results implied that delivery of RS loaded cationic liposomes substantially controlled the severity of HCC and that they can be considered as a promising nanocarrier in the management of HCC.

Novel On-Demand 3-Dimensional (3-D) Printed Tablets Using Fill Density as an Effective Release-Controlling Tool

This research demonstrates the use of fill density as an effective tool for controlling the drug release without changing the formulation composition. The merger of hot-melt extrusion (HME) with fused deposition modeling (FDM)-based 3-dimensional (3-D) printing processes over the last decade has directed pharmaceutical research towards the possibility of printing personalized medication. One key aspect of printing patient-specific dosage forms is controlling the release dynamics based on the patient's needs. The purpose of this research was to understand the impact of fill density and interrelate it with the release of a poorly water-soluble, weakly acidic, active pharmaceutical ingredient (API) from a hydroxypropyl methylcellulose acetate succinate (HPMC-AS) matrix, both mathematically and experimentally. Amorphous solid dispersions (ASDs) of ibuprofen with three grades of AquaSolveTM HPMC-AS (HG, MG, and LG) were developed using an HME process and evaluated using solid-state characterization techniques. Differential scanning calorimetry (DSC), powder X-ray diffraction (pXRD), and polarized light microscopy (PLM) confirmed the amorphous state of the drug in both polymeric filaments and 3D printed tablets. The suitability of the manufactured filaments for FDM processes was investigated using texture analysis (TA) which showed robust mechanical properties of the developed filament compositions. Using FDM, tablets with different fill densities (20-80%) and identical dimensions were printed for each polymer. In vitro pH shift dissolution studies revealed that the fill density has a significant impact (F(11, 24) = 15,271.147, p < 0.0001) and a strong negative correlation (r > -0.99; p < 0.0001) with the release performance, where 20% infill demonstrated the fastest and most complete release, whereas 80% infill depicted a more controlled release. The results obtained from this research can be used to develop a robust formulation strategy to control the drug release from 3D printed dosage forms as a function of fill density.

Optimal Design, Characterization and Preliminary Safety Evaluation of an Edible Orodispersible Formulation for Pediatric Tuberculosis Pharmacotherapy

The severity of tuberculosis (TB) in children is considered a global crisis compounded by the scarcity of pharmaceutical formulations suitable for pediatric use. The purpose of this study was to optimally develop and evaluate a pyrazinamide containing edible orodispersible film formulation potentially suitable for use in pediatrics actively infected with TB. The formulation was prepared employing aqueous-particulate blending and solvent casting methods facilitated by a high performance Box Behnken experimental design template. The optimized orodispersible formulation was mechanically robust, flexible, easy to handle, exhibited rapid disintegration with initial matrix collapse occurring under 60 s (0.58 ± 0.05 min ≡ 34.98 ± 3.00 s) and pyrazinamide release was controlled by anomalous diffusion coupled with matrix disintegration and erosion mechanisms. It was microporous in nature, light weight (57.5 ± 0.5 mg) with an average diameter of 10.5 mm and uniformly distributed pyrazinamide load of 101.13 ± 2.03 %^w/_w. The formulation was physicochemically stable with no evidence of destructive drug–excipient interactions founded on outcomes of characterization and environmental stability investigations. Preliminary inquiries revealed that the orodispersible formulation was cytobiocompatible, palatable and remained intact under specific storage conditions. Summarily, an edible pyrazinamide containing orodispersible film formulation was optimally designed to potentially improve TB pharmacotherapy in children, particularly the under 5 year olds.

Basit A. 3D Printing of Tunable Zero-Order Release Printlets

Zero-order release formulations are designed to release a drug at a constant rate over a prolonged time, thus reducing systemic side effects and improving patience adherence to the therapy. Such formulations are traditionally complex to manufacture, requiring multiple steps. In this work, fused deposition modeling (FDM) 3D printing was explored to prepare on-demand printlets (3D printed tablets). The design includes a prolonged release core surrounded by an insoluble shell able to provide zero-order release profiles. The effect of drug loading (10, 25, and 40% w/w paracetamol) on the mechanical and physical properties of the hot melt extruded filaments and 3D printed formulations was evaluated. Two different shell 3D designs (6 mm and 8 mm diameter apertures) together with three different core infills (100, 50, and 25%) were prepared. The formulations showed a range of zero-order release profiles spanning 16 to 48 h. The work has shown that with simple formulation design modifications, it is possible to print extended release formulations with tunable, zero-order release kinetics. Moreover, by using different infill percentages, the dose contained in the printlet can be infinitely adjusted, providing an additive manufacturing route for personalizing medicines to a patient.