Development of a novel cannabinoid-loaded microemulsion towards an improved stability and transdermal delivery

Cutaneous Pharmacokinetics of Topically Applied Novel Dermatological Formulations

Novel formulations are developed for dermatological applications to address a wide range of patient needs and therapeutic challenges. By pushing the limits of pharmaceutical technology, these formulations strive to provide safer, more effective, and patient-friendly solutions for dermatological concerns, ultimately improving the overall quality of dermatological care. The article explores the different types of novel dermatological formulations, including nanocarriers, transdermal patches, microsponges, and microneedles, and the techniques involved in the cutaneous pharmacokinetics of these innovative formulations. Furthermore, the significance of knowing cutaneous pharmacokinetics and the difficulties faced during pharmacokinetic assessment have been emphasized. The article examines all the methods employed for the pharmacokinetic evaluation of novel dermatological formulations. In addition to a concise overview of earlier techniques, discussions on novel methodologies, including tape stripping, in vitro permeation testing, cutaneous microdialysis, confocal Raman microscopy, and matrix-assisted laser desorption/ionization mass spectrometry have been conducted. Emerging technologies like the use of microfluidic devices for skin absorption studies and computational models for predicting drug pharmacokinetics have also been discussed. This article serves as a valuable resource for researchers, scientists, and pharmaceutical professionals determined to enhance the development and understanding of novel dermatological drug products and the complex dynamics of cutaneous pharmacokinetics.

Potential strategy of microneedle-based transdermal drug delivery system for effective management of skin-related immune disorders

Skin-related immune disorders are a category of diseases that lead to the dysregulation of the body's immune response due to imbalanced immune regulation. These disorders exhibit diverse clinical manifestations and complicated pathogenesis. The long-term use of corticosteroids, anti-inflammatory drugs, and immunosuppressants as traditional treatment methods for skin-related immune disorders frequently leads to adverse reactions in patients. In addition, the effect of external preparations is not ideal in some cases due to the compacted barrier function of the stratum corneum (SC). Microneedles (MNs) are novel transdermal drug delivery systems that have theapparent advantages ofpenetrating the skin barrier, such as long-term and controlled drug delivery, less systemic exposure, and painless and minimally invasive targeted delivery. These advantages make it a good candidate formulation for the treatment of skin-related immune disorders and a hotspot for research in this field. This paper updates the classification, preparation, evaluation strategies, materials, and related applications of five types of MNs. Specific information, including the mechanical properties, dimensions, stability, and in vitro and in vivo evaluations of MNs in the treatment of skin-related immune disorders, is also discussed. This review provides an overview of the advances and applications of MNs in the effective treatment of skin-related immune disorders and their emerging trends.

Novel phenolate salts of bioactive agents: Cannabidiol phenolate salts

Bioactive phenolic compounds are commonly found in medications, with examples including apomorphine, estrone, thymol, estradiol, propofol, o-phenylphenol, l-Dopa, doxorubicin, tetrahydrocannabinol (THC), and cannabidiol (CBD). This study is the first to explore the creation and assessment of metal and ammonium phenolate salts using CBD as an example. CBD is used in medicine to treat anxiety, insomnia, chronic pain, and inflammation, but its bioavailability is limited due to poor water solubility. In this study exploit a synthetic route to convert CBD into anionic CBD-salts to enhance water solubility. Various CBD-salts with metal and ammonium counterions such as lithium (Li+), sodium (Na+), potassium (K+), choline hydroxide ([(CH3)3NCH2CH2OH]+), and tetrabutylammonium ([N(C4H9)4]+) have been synthesized and characterized. These salts are obtained in high yields, ranging from 74 % to 88 %, through a straightforward dehydration reaction between CBD and alkali metal hydroxides (LiOH, NaOH, KOH) or ammonium hydroxides (choline hydroxide, tetrabutylammonium hydroxide). These reactions are conducted in either ethanol, methanol, or a methanol:water mixture, maintaining a 1:1 molar ratio between the reactants. Comprehensive characterization using Fourier-Transform Infrared Spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy, and elemental (CHN) analysis confirms the formation of CBD-salts, as evidenced by the absence of aromatic hydroxyl resonances or stretching frequencies. The molecular formulas of CBD salts were determined based on CHN analysis, and CBD quantification from acid regeneration experiments. Characterization data confirms that each CBD phenolate in a specific CBD salt was electrostatically stabilized by one of the either alkali metal or ammonium ion. The CBD-salts are highly susceptible to acidic conditions, readily reverting back to the original CBD. The percentage and purity of CBD in the CBD-metal/ammonium salts have been studied using High-Performance Liquid Chromatography (HPLC) analysis. Solubility studies indicate that the conversion of CBD into CBD salts significantly enhances its solubility in water, ranging from 110 to 1606 folds greater than pure CBD. Furthermore, the pharmacokinetic evaluation of oral administration of CBD-salts compared to CBD were determined in rats.

Development of an UHPLC-MS/MS method to determine cutaneous biodistribution of cannabidiol after topical application of cannabidiol gel assisted by iontophoresis

Cannabidiol has potential for use in skin disease therapy, so it is important to know the cutaneous biodistribution of cannabidiol after topical application of cannabidiol formulations. However, currently existing quantification methods for the investigation of cannabidiol skin distribution are not optimal. This study aimed to establish a method for the determination of cannabidiol in skin samples by UHPLC-MS/MS. A BEH C18 (50.0 × 2.1 mm, 2.5 μm) column was used; the mobile phase consisted of acetonitrile-0.1% formic acid (70:30, v/v), the flow rate was 0.2 μl·min-1 and the column temperature was 30°C. Positive-ion mode with multiple reaction monitoring detection was used to quantify cannabidiol (m/z 315.1 → 193.1) while diphenhydramine (m/z 256.3 → 167.08) served as the internal standard. Good linearity was shown in the range of 1-200 ng·ml-1 for cannabidiol with correlation coefficients of >0.999. The LLOQ was 1 ng·ml-1 . The intra-day and inter-day RSDs of cannabidiol were all <2%. A cryo-sectioning technique combined with the UHPLC-MS/MS method was used to successfully determine cannabidiol levels in a series of very thin skin layers.

Investigation of Cannabinoid Acid/Cyclodextrin Inclusion Complex for Improving Physicochemical and Biological Performance

This study aimed to investigate the enhancement of cannabinoid acid solubility and stability through the formation of a cannabinoid acid/cyclodextrin (CD) inclusion complex. Two cannabinoid acids, tetrahydro-cannabinolic acid (THCA) and cannabidiolic acid (CBDA), were selected as a model drug along with five types of CD: α-cyclodextrin (α-CD), β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), and methylated-β-cyclodextrin (M-β-CD). Phase solubility studies were conducted using various types of CD to determine the complex stoichiometry. The preparation methods of the CD inclusion complex were optimized by adjusting the loading pH solution and the drying processes (spray-drying, freeze-drying, spray-freeze-drying). The drying process of the cannabinoid acid/M-β-CD inclusion complex was further optimized through the spray-freeze-drying method. These CD complexes were characterized using solubility determination, differential scanning calorimetry (DSC), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), and 1H NMR spectroscopy. DSC, XRD, and FE-SEM studies confirmed the non-crystalline state of the cannabinoid acid/CD inclusion complex. The permeation of THCA or CBDA from the M-β-CD spray-freeze-dried inclusion complex was highly improved compared to those of cannabis ethanolic extracts under simulated physiological conditions. The stability of the cannabinoid acid/M-β-CD inclusion complex was maintained for 7 days in a simulated physiological condition. Furthermore, the minimum inhibitory concentration of cannabinoid acid/M-β-CD inclusion complex had superior anti-cancer activity in MCF-7 breast cancer cell lines compared to cannabinoid acid alone. The improved physicochemical and biological performances indicated that these CD inclusion complexes could provide a promising option for loading lipophilic cannabinoids in cannabis-derived drug products.

The Skin and Natural Cannabinoids-Topical and Transdermal Applications

The chemical constituents of the Cannabis plant known as cannabinoids have been extensively researched for their potential therapeutic benefits. The use of cannabinoids applied to the skin as a potential method for both skin-related benefits and systemic administration has attracted increasing interest in recent years. This review aims to present an overview of the most recent scientific research on cannabinoids used topically, including their potential advantages for treating a number of skin conditions like psoriasis, atopic dermatitis, and acne. Additionally, with a focus on the pharmacokinetics and security of this route of administration, we investigate the potential of the transdermal delivery of cannabinoids as a method of systemic administration. The review also discusses the restrictions and difficulties related to the application of cannabinoids on the skin, emphasizing the potential of topical cannabinoids as a promising route for both localized and systemic administration. More studies are required to fully comprehend the efficacy and safety of cannabinoids in various settings.

Influence of a Transparent and Edible Coating of Encapsulated Cannabidiol Nanoparticles on the Quality and Shelf Life of Strawberries

Cannabidiol (CBD) has been shown to have antioxidant and antibacterial effects. The investigation into CBD's potential as an antioxidant and antibacterial agent, meanwhile, is still in its initial stages. The study goals were to prepare encapsulated cannabidiol isolate (eCBDi), evaluate the effect of eCBDi edible active coatings on the physicochemical properties of strawberries, and determine whether CBD and sodium alginate coatings could be used as a postharvest treatment to promote antioxidation and antimicrobial activity and prolong the strawberry shelf life. A well-designed edible coating on the strawberry surface was achieved using eCBDi nanoparticles in combination with a sodium alginate polysaccharide-based solution. Strawberries were examined for their visual appearance and quality parameters. In the results, a significantly delayed deterioration was observed in terms of weight loss, total acidity, pH, microbial activity, and antioxidant activity for coated strawberries compared to the control. This study demonstrates the capability of eCBDi nanoparticles as an efficient active food coating agent.

Cannabinoid-Based Ocular Therapies and Formulations

The interest in the pharmacological applications of cannabinoids is largely increasing in a wide range of medical areas. Recently, research on its potential role in eye conditions, many of which are chronic and/or disabling and in need of new alternative treatments, has intensified. However, due to cannabinoids’ unfavorable physicochemical properties and adverse systemic effects, along with ocular biological barriers to local drug administration, drug delivery systems are needed. Hence, this review focused on the following: (i) identifying eye disease conditions potentially subject to treatment with cannabinoids and their pharmacological role, with emphasis on glaucoma, uveitis, diabetic retinopathy, keratitis and the prevention of Pseudomonas aeruginosa infections; (ii) reviewing the physicochemical properties of formulations that must be controlled and/or optimized for successful ocular administration; (iii) analyzing works evaluating cannabinoid-based formulations for ocular administration, with emphasis on results and limitations; and (iv) identifying alternative cannabinoid-based formulations that could potentially be useful for ocular administration strategies. Finally, an overview of the current advances and limitations in the field, the technological challenges to overcome and the prospective further developments, is provided.

Targeting the endocannabinoid system for the treatment of abdominal pain in irritable bowel syndrome

The management of visceral pain in patients with disorders of gut-brain interaction, notably irritable bowel syndrome, presents a considerable clinical challenge, with few available treatment options. Patients are increasingly using cannabis and cannabinoids to control abdominal pain. Cannabis acts on receptors of the endocannabinoid system, an endogenous system of lipid mediators that regulates gastrointestinal function and pain processing pathways in health and disease. The endocannabinoid system represents a logical molecular therapeutic target for the treatment of pain in irritable bowel syndrome. Here, we review the physiological and pathophysiological functions of the endocannabinoid system with a focus on the peripheral and central regulation of gastrointestinal function and visceral nociception. We address the use of cannabinoids in pain management, comparing them to other treatment modalities, including opioids and neuromodulators. Finally, we discuss emerging therapeutic candidates targeting the endocannabinoid system for the treatment of pain in irritable bowel syndrome.

Fluocinolone Acetonide Microemulsion in Combination with a Fractional Laser for the Treatment of Scalp Psoriasis

This study introduces fluocinolone acetonide (FA) microemulsion in combination with ablative fractional lasering as a new effective treatment for scalp psoriasis. A pseudo-ternary phase diagram was constructed using the aqueous titration method. The suitable ratio of surfactant mixture (S_mix):oil mixture (O_mix):water was chosen from the microemulsion region of the diagram. FA was loaded into the selected ratio to prepare FA microemulsion. Ex vivo skin permeation study of the FA microemulsion with fractional laser assistance was performed to determine a proper ablative depth. A pilot clinical study was conducted to evaluate the efficacy of FA microemulsion and FA microemulsion combination with lasering at the optimum ablation depth. The selected microemulsion base contained (in wt%) 77% water, 20% S_mix (Tween 80:ethanol, 2:1), 3% O_mix (10% benzyl benzoate and 1% benzyl alcohol in bergamot oil), and 0.2% sodium carboxymethylcellulose. FA was loaded into this base at a concentration of 0.1%. The skin lasered at an ablation depth of 50 µm was conducted in the pilot clinical study. Scalp psoriasis responded well to the FA microemulsion. Psoriasis scalp severity index (PSSI) scores indicated that the FA microemulsion plus laser treatment provides higher efficacy than the FA microemulsion alone without any topical and systemic side effects. The efficacy of the treatments could be maintained for at least 1 week after treatment discontinuation. FA microemulsion was properly formulated and evaluated. The microemulsion demonstrating the greatest benefits was used in combination with ablative fractional lasering to treat scalp psoriasis.

Cannabidiolic acid in Hemp Seed Oil Table Spoon and Beyond

Cannabidiolic acid (CBDA) is the main precannabinoid in industrial hemp. It represents a common constituent of hemp seed oil, but mainly abundant in the aerial parts of the plant (including their processing waste). Thus, the optimization of fast and low-cost purification strategies is mandatory, as well as a deep investigation on its nutraceutical and cosmeceutical properties. To this purpose, CBDA content in hemp seed oil is evaluated, and its recovery from wasted leaves is favorably achieved. The cytotoxicity screening towards HaCaT cells, by means of MTT, SRB and LDH release assays, suggested it was not able to decrease cell viability or perturb cell integrity up to 10 μM concentration. Thus, the ability of CBDA to differentially modulate the release of proinflammatory cytokines and chemokines mediators has been evaluated, finding that CBDA decreased IFN-γ, CXCL8, CXCL10, CCL2, CCL4 and CCL5, mostly in a dose-dependent manner, with 10 μM tested concentration exerting the highest activity. These data, together with those from assessing antimicrobial activity against Gram(+) and Gram(−) bacteria and the antibiofilm formation, suggest that CBDA is able to counteract the inflammatory response, also preventing bacteria colonization.

The Transdermal Delivery of Therapeutic Cannabinoids

Recently, several studies have indicated an increased interest in the scientific community regarding the application of Cannabis sativa plants, and their extracts, for medicinal purposes. This plant of enormous medicinal potential has been legalised in an increasing number of countries globally. Due to the recent changes in therapeutic and recreational legislation, cannabis and cannabinoids are now frequently permitted for use in clinical settings. However, with their highly lipophilic features and very low aqueous solubility, cannabinoids are prone to degradation, specifically in solution, as they are light-, temperature-, and auto-oxidation-sensitive. Thus, plant-derived cannabinoids have been developed for oral, nasal-inhalation, intranasal, mucosal (sublingual and buccal), transcutaneous (transdermal), local (topical), and parenteral deliveries. Among these administrations routes, topical and transdermal products usually have a higher bioavailability rate with a prolonged steady-state plasma concentration. Additionally, these administrations have the potential to eliminate the psychotropic impacts of the drug by its diffusion into a nonreactive, dead stratum corneum. This modality avoids oral administration and, thus, the first-pass metabolism, leading to constant cannabinoid plasma levels. This review article investigates the practicality of delivering therapeutic cannabinoids via skin in accordance with existing literature.

Development of Licorice Flavonoids Loaded Microemulsion for Transdermal Delivery Using CCD-Optimal Experimental Approach: Formulation Development and Characterization

In this research, we sought to surmount the poor dissolvability and transdermal absorption rate of licorice flavonoids (LFs) by fabricating a LFs microemulsion. LFs content was determined using high performance liquid chromatography. Initial studies such as dissolution testing, emulsification testing, and pseudo ternary phase diagram generation were implemented for screening components and optimized adopting the central composite design. While the tested responses were solubility, droplet size and PDI, thirteen trials were performed using two different variables, oil percentage and optimized emulsifier and co-emulsifier ratio. Microemulsions were then characterized for droplet size, PDI, transmission electron microscopy, viscosity, electrical conductivity, pH, entrapment efficiency, drug content and stability. Additionally, skin release profile, percutaneous absorption and retention were investigated adopting Franz diffusion cell. The optimal formulation was found to compose of laureth-9 (emulsifier, 6.72 g), propylene glycol (co-emulsifier, 1.80 g), isopropyl myristate (IPM, oil, 1.48 g), LFs (1.50 g) and at least more than 85% deionized water. The optimized and storage for 3 months of microemulsion was found to clear, light yellow color without phase separation or precipitation indicated the stability of the preparation to long-term placement. The mean droplet size, PDI, entrapment efficiency and drug content were discovered as 12.68 ± 0.12 nm, 0.049 ± 0.005, 97.28 ± 0.13% and 122.67 ± 0.40 mg·g−1, respectively. Furthermore, the optimal formulation sustained release LFs, remarkably deliver more LFs through the skin layer (644.95 ± 6.73 μg cm−2) and significantly retained LFs in the skin layer (9.98 μg cm−2). The study concluded that optimized microemulsion has potential and enhanced the dissolvability and cumulative penetration amount of LFs.

O/W microemulsion droplets diffuse through hydrogel network to achieve enhanced transdermal drug delivery

To overcome the poor water solubility of total flavones of Arisaematis rhizoma, microemulsions (MEs) can be used as a carrier for transdermal administration to promote their solubilization and skin permeability. Here, we investigated the physical compatibility of MEs in hydrogels and their skin permeation-enhancing effects. Transparency of microemulsion-based hydrogels (MBGs) was analyzed to evaluate ME compatibility with different hydrogel matrices. Transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) spectroscopy were used to explore the microstructures of MBGs and ME–hydrogel combinations. Uniform and transparent MBG was obtained by adding 1% sodium hyaluronate (SH) to the optimized ME. MBG prepared with SH as a matrix expressed pseudoplastic-fluid and shear-thinning characteristics, making it easy to apply in clinical settings. No new FTIR peak occurred in the MBG compared with ME and hydrogel matrix, indicating a physical combination of ME and the polymer network gel. Nanoscale droplets of ME migrated in the gel network, and the migration capacity and in vitro transdermal permeation flux negatively correlated with SH concentration in the gel system. In conclusion, in MBGs, ME can keep nanoscale droplets migrating in the hydrogel network, thereby enhancing transdermal drug delivery.