Improved bioavailability of timolol maleate via transdermal transfersomal gel: Statistical optimization, characterization, and pharmacokinetic assessment

The pulmonary protective potential of vanillic acid-loaded TPGS-liposomes: modulation of miR-217/MAPK/NF-κb signalling pathway

The aim is to investigate the possible pulmonary protective effect of vanillic acid (VA) in liposome-TPGS nanoparticles, to overcome VA's poor bioavailability. VA was successfully extracted. Liposomes were prepared using thin film hydration. Central composite design was adopted for optimisation of liposomes to get the maximum entrapment efficiency (EE%) and the minimum mean diameter, where the liposomes were further modified with TPGS, and tested for PDI, zeta-potential, and in-vitro drug release. In-vivo study on mice with LPS-acute pulmonary toxicity was tested. TPGS-modified VA-liposomes showed EE% of 69.35 ± 1.23%, PS of 201.7 ± 3.23 nm, PDI of 0.19 ± 0.02, and zeta-potential of -32.2 ± 0.32 mv. A sustained drug release of the TPGS-modified VA-liposomes was observed compared to standard VA, and a pulmonary-protective effect through decreasing miR-217 expression with subsequent anti-inflammatory effect through suppression of MAPK and PI3K/NF-κB pathways was also demonstrated in the current study. TPGS-modified VA-liposomes showed an enhanced bioavailability and a sustained drug release with promising pulmonary protective effects against acute pulmonary injury diseases.

A microneedle patch realizes weight loss through photothermal induction of fat browning

As a globally prevalent disease, obesity leads to many chronic diseases, so it is important to develop safe and effective treatments with fewer side effects and lasting weight loss. In this study, we developed a biodegradable hyaluronic acid microneedle patch loaded with polydopamine nanoparticles and mirabegron, which directly acted on subcutaneous white adipose tissue, and then induced browning of white adipose tissue through mild photothermal therapy. The approach showed excellent browning-promoting ability and biocompatibility. It is noteworthy that the weight of untreated mice increased by 9%, while the weight of obese mice decreased by nearly 19% after photothermal treatment. In addition, when mirabegron was used in combination with photothermal therapy, the weight loss of obese mice was more significant, with a weight loss of about 22%. This microneedle patch exhibited attractive potential for body slimming.

Engineering nanosystems for transdermal delivery of antihypertensive drugs

To control hypertension, long-term continuous antihypertensive therapeutics are required and five classes of antihypertensive drugs are frequently involved, including diuretics, β-blockers, calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors. Although with demonstrated clinical utility, there is still room for the improvement of many antihypertensive drugs in oral tablet or capsule dosage form, in terms of reducing systemic side effects and first-pass hepatic drug uptake. Meanwhile, nanocarrier-mediated transdermal drug delivery systems have emerged as a powerful tool for various disease treatments. With benefits such as promoting patient compliance for long-time administration, enhancing skin permeability, and reducing systemic side effects, these systems are reasonably investigated and developed for the transdermal delivery of multiple antihypertensive drugs. This review aims to summarize the literature relating to nanosystem-based transdermal antihypertensive drug delivery and update recent advances in this field, as well as briefly discuss the challenges and prospects of engineering transdermal delivery nanosystems for hypertension treatment.

Development of mucoadhesive Timolol loaded chitosan-nanocomposite to treat glaucoma

Timolol Maleate is an aqueous soluble β-blocker antiglaucoma drug used to suppress intraocular pressure. Several commercially available ocular formulations are not effective in delivering to the target site due to their water-soluble property and low mucoadhesiveness. Hence, there is a requirement for a highly mucoadhesive drug-loaded nanocomposite to suppress intraocular pressure with enhanced bioavailability. Herein, we have prepared a mucoadhesive Timolol-loaded graphene quantum dot-chitosan-nanocomposite to treat glaucoma in response to lysozyme, secreted in the tear fluid. The as-prepared nanocomposite has been characterized through high resolution-transmission electron microscopic, X-ray photoelectron spectroscopic, X-ray diffraction, and Fourier transform infrared spectral studies. The nanocomposite showed 93.74 % encapsulation efficiency with a loading capacity of 7.73 %. Further, 89.26 %, 95.62 %, and 99.29 % of drug release were observed from the nanocomposite in the presence of 1, 1.5, and 2 mg/mL of lysozyme. The mucoadhesion property has been confirmed by the increment in the particle size, fluorescence spectral variations, and Fourier transform infrared spectroscopic studies in the presence of mucin nanoparticles of size 291 nm. Interestingly, mucoadhesion has been demonstrated by pointing to the quenching in the luminescence of mucin. Further, in vitro biocompatibility assay on human corneal epithelial cells showed ≥80 % cell viability. Hence, this study offers the utilization of naturally secreting enzymes for drug delivery applications instead of uncontrolled pH and temperature-triggered releases.

Quality-by-design-based development of ultradeformable nanovesicular transgelosome of standardized Piper longum extract for melanoma

Background: Melanoma is the most aggressive and deadly form of skin cancer. The stratum corneum of the skin is a major obstacle to dermal and transdermal drug delivery. Ultradeformable nanovesicular transferosome has the capacity for deeper skin penetration and its incorporation into hydrogel forms a transgelosome that has better skin permeability and patient compliance. Method: Here, the quality-by-design-based development and optimization of nanovesicular transgelosome of standardized Piper longum fruit ethanolic extract (PLFEE) for melanoma therapy are reported. Results: Compared with standardized PLFEE-loaded plain gel, the transgelosome displayed optimal pharmaceutical properties and improved ex vivo skin permeability and in vivo tumor regression in B16F10 melanoma-bearing C57BL/6 mice. Conclusion: The results reflect the potential of transgelosome for melanoma therapy.

Recent Options and Techniques to Assess Improved Bioavailability: In Vitro and Ex Vivo Methods

Bioavailability assessment in the development phase of a drug product is vital to reveal the disadvantageous properties of the substance and the possible technological interventions. However, in vivo pharmacokinetic studies provide strong evidence for drug approval applications. Human and animal studies must be designed on the basis of preliminary biorelevant experiments in vitro and ex vivo. In this article, the authors have reviewed the recent methods and techniques from the last decade that are in use for assessing the bioavailability of drug molecules and the effects of technological modifications and drug delivery systems. Four main administration routes were selected: oral, transdermal, ocular, and nasal or inhalation. Three levels of methodologies were screened for each category: in vitro techniques with artificial membranes; cell culture, including monocultures and co-cultures; and finally, experiments where tissue or organ samples were used. Reproducibility, predictability, and level of acceptance by the regulatory organizations are summarized for the readers.

Development and optimization of a tamsulosin nanostructured lipid carrier loaded with saw palmetto oil and pumpkin seed oil for treatment of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a nonmalignant growth of the prostate tissue and causes urinary tract symptoms. To provide effective treatment, tamsulosin (TM), saw palmetto oil (SP), and pumpkin seed oil (PSO) were combined and fabricated a nanostructured lipid carrier (NLC) as TM-S/P-NLC using experimental design. The purpose was to enhance the permeation and therapeutic activity of TM; combining TM with SP and PSO in an NLC generates a synergistic activity. An optimized TM-S/P-NLC was obtained after statistical analysis, and it had a particle size, percentage of entrapment efficiency, and steady-state flux of 102 nm, 65%, and 4.5 μg/cm².min, respectively. Additionally, the optimized TM-S/P-NLC had spherical particles with a more or less uniform size and a stability score of 95%, indicating a high level of stability. The in vitro release studies exhibited the optimized TM-S/P-NLC had the maximum release profile for TM (81 ± 4%) as compared to the TM-NLCs prepared without the addition of S/P oil (59 ± 3%) or the TM aqueous suspension (30 ± 5%). The plasma TM concentration–time profile for the TM-S/P-NLC and the marketed TM tablets indicated that when TM was supplied in a TM-S/P-NLC, the pharmacokinetic profile of the drug was improved. Simultaneously, in vivo therapeutic efficacy studies also showed favorable results for the TM-S/P-NLC in terms of the prostate weight and prostate index following treatment of BPH. Based on the findings of present study, we suggest that in the future, the TM-S/P-NLC could be a novel drug delivery system for treating BPH.

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.

New Peceol™/Span™ 60 Niosomes Coated with Chitosan for Candesartan Cilexetil: Perspective Increase in Absolute Bioavailability in Rats

PURPOSE

Candesartan cilexetil (CC), a prodrug of candesartan (CDT), is a class II BCS drug that suffers from poor oral bioavailability because of low aqueous solubility, P-gp efflux and first-pass metabolism. The absolute bioavailability reported for CC was only 15% and the methods to increase it remain elusive, thus the aim of our work was to prepare new CC-loaded niosomes encompassing, for the first time, glycerol monooleate GMO (Peceol™), as P-gp efflux inhibitor and promoter of lymphatic transport with Span™ 60 as bioenhancer. The prepared niosomes were further coated with chitosan for augmenting the CC oral absorption.

METHODS

The niosomes were prepared by thin film hydration method through quality by design approach, using two levels of each of three critical process parameters (CPPs), namely, XA (the molar ratio of surfactant mixture to cholesterol) at a ratio of 1:1 or 2:1; XB (the molar ratio of Span™ 60 to Peceol™) at a ratio of 1:1 or 2:1; and XC (the drug amount) at 15 mg or 30 mg. The investigated critical quality attributes (CQAs) were entrapment efficiency percent, particle size, and polydispersity index. The optimized uncoated and chitosan coated formulations were subjected to DSC and stability study. In vitro drug release, biocompatibility with Caco-2 cells and lastly the absolute bioavailability evaluation in rats were assessed.

RESULTS

The physical properties of the optimized and stable niosomes were satisfactory. The ingredients were compatible with each other and biocompatible with Caco-2 cells. The synergistic combination of Peceol™ and Span™ 60 probably surmounted the P-gp efflux with an increase in oral absolute bioavailability of niosomes to five times that of CC suspension.

CONCLUSION

The new niosomal formulations of CC containing Peceol™ with Span™ 60 and cholesterol either uncoated or coated with chitosan were a successful paradigm in achieving high oral absolute bioavailability and increased Caco-2 cells biocompatibility.

Development of polymeric nanoparticle gel prepared with the combination of ionic pre-gelation and polyelectrolyte complexation as a novel drug delivery of timolol maleate

OBJECTIVE

The purpose of this study was to overcome the undesired systemic absorption of skin topical administration of timolol maleate (TM) by developing the TM nanoparticle gel.

METHODS

TM-loaded nanoparticle (TMNP) was prepared by ionic pre-gelation of pectin (PCN) and calcium ions (CI) followed with polyelectrolyte complex using chitosan (CHI). TMNP was characterized by measuring the particle size, polydispersity index, zeta potential, encapsulation efficiency (EE), and the interaction between formula constituents. TM-loaded nanoparticle gel (TMNG) was prepared by using hydroxypropyl methylcellulose (HPMC) and was characterized by measuring the spreadability, pH, viscosity, and drug content. The drug release kinetics were analyzed using DDSolver add-in program.

RESULTS

TMNP possessed particle size of 175.2 ± 19.7 nm, polydispersity index of 0.528 ± 0.113, zeta potential of -10.86 ± 0.87 mV, and EE of 27.45 ± 2.34%. The electrostatic interactions between PCN, CI, and CHI that formed the nanoparticles were confirmed by the result of vibrational spectroscopy analysis. TMNG possessed spreadability of 60.80 ± 1.38 cm², pH of 5.154 ± 0.004, viscosity of 269.07 ± 5.83 cP, and drug content of 107.38 ± 1.77%. TM showed a sustained release manner within 24 h by following Korsmeyer-Peppas kinetical model with non-Fickian release mechanism.

CONCLUSION

The prepared nanoparticle gel can be an effective controlled release system of TM that administered topically on the skin surface.

Half-life determination of inorganic-organic hybrid nanomaterials in mice using laser-induced breakdown spectroscopy

Inorganic or inorganic-organic hybrid nanomaterials have great potential for applications in the biomedical fields. Biological half-life is an essential pharmacokinetic parameter for these materials to function in vivo. Compared to inductively coupled plasma mass spectrometry (ICP-MS), which is the gold standard, laser-induced breakdown spectroscopy (LIBS) is a faster and more efficient elemental detection method. We investigated an efficient way to quantify the metabolic rate using LIBS. Nanoparticle platforms, such as manganese dioxide-bovine serum albumin (MnO2-BSA) or boehmite-bovine serum albumin (AlO(OH)-BSA) were injected into mice through intravenous administration for LIBS spectrum acquisition. First, the spectral background was corrected using the polynomial fitting method; The spectral interference was eliminated by Lorentz fitting for each LIBS spectrum simultaneously. The support vector regression (SVR) was then used for LIBS quantitative analyses. Finally, the LIBS results were compared with the ICP-MS ones. The half-lives of MnO2-BSA calculated by LIBS and ICP-MS were 2.49 and 2.42 h, respectively. For AlO(OH)-BSA, the half-lives detected by LIBS and ICP-MS were 3.46 and 3.57 h, respectively. The relative error of LIBS is within 5% compared to ICP-MS. The results demonstrate that LIBS is a valuable tool for quantifying the metabolic rates with a high degree of accuracy.

Phospholipid Vesicles for Dermal/Transdermal and Nasal Administration of Active Molecules: The Effect of Surfactants and Alcohols on the Fluidity of Their Lipid Bilayers and Penetration Enhancement Properties

This is a comprehensive review on the use of phospholipid nanovesicles for dermal/transdermal and nasal drug administration. Phospholipid-based vesicular carriers have been widely investigated for enhanced drug delivery via dermal/transdermal routes. Classic phospholipid vesicles, liposomes, do not penetrate the deep layers of the skin, but remain confined to the upper stratum corneum. The literature describes several approaches with the aim of altering the properties of these vesicles to improve their penetration properties. Transfersomes and ethosomes are the most investigated penetration-enhancing phospholipid nanovesicles, obtained by the incorporation of surfactant edge activators and high concentrations of ethanol, respectively. These two types of vesicles differ in terms of their structure, characteristics, mechanism of action and mode of application on the skin. Edge activators contribute to the deformability and elasticity of transfersomes, enabling them to penetrate through pores much smaller than their own size. The ethanol high concentration in ethosomes generates a soft vesicle by fluidizing the phospholipid bilayers, allowing the vesicle to penetrate deeper into the skin. Glycerosomes and transethosomes, phospholipid vesicles containing glycerol or a mixture of ethanol and edge activators, respectively, are also covered. This review discusses the effects of edge activators, ethanol and glycerol on the phospholipid vesicle, emphasizing the differences between a soft and an elastic nanovesicle, and presents their different preparation methods. To date, these differences have not been comparatively discussed. The review presents a large number of active molecules incorporated in these carriers and investigated in vitro, in vivo or in clinical human tests.

Reduction of intraocular pressure using timolol orally dissolving strips in the treatment of induced primary open-angle glaucoma in rabbits

OBJECTIVE

To enhance bioavailability of timolol (TML) and utilize alternatives for traditional eye drops for more patient compliance, this study was aiming to develop biodegradable orally dissolving strips (ODSs) of TML for treatment of primary open-angle glaucoma (POAG).

METHODS

Novel ODSs of TML were formulated and optimized using solvent casting method according to full factorial design (3¹ .2² ). TML ODSs were characterized with respect to many parameters. In-vivo test was carried out using four groups of 24 New Zealand albino rabbits. POAG was induced by subconjunctival treatment of betamethasone. Histopathological examination and oxidative stress markers assay were carried out.

KEY FINDINGS

The optimized formula (F9) exhibited a remarkably 15-s disintegration time and 96% dissolution rate after 10 min. The results revealed a potent significant inhibitory effect of the optimized TML ODS to reduce IOP in induced rabbits in comparison with control rabbits and TML eye drops-treated rabbits. The formula showed also high activity against oxidative stress and absence of histopathological changes in iridocorneal angle and cornea.

CONCLUSION

The ODSs could be a promising alternative delivery system for eye drops with more compliance to enhance delivery and therapeutic activity of TML in treatment of POAG.

Percutaneous Delivery of Antihypertensive Agents: Advances and Challenges

Hypertension remains a significant risk factor for several cardiovascular disorders including coronary artery disease and heart failure. Despite the large armamentarium of drugs available for the management of high blood pressure, low oral availability is an ongoing challenge. Researchers are constantly developing alternative drug delivery systems. This review focuses on the transcutaneous delivery of antihypertensive agents. The use of diverse technologies for the delivery of specific antihypertensive agents is emphasized. The advances made and the challenges encountered are highlighted. Several transdermal drug delivery strategies are employed for the transport of this group of therapeutic agents across the skin and the most widely used techniques include microneedles, iontophoresis, sonophoresis, and chemical penetration enhancers. Each of these methods has benefits and limitations, and there are ongoing attempts by scientists to address the shortcomings. For instance, skin irritation continues to be a major challenge with iontophoretic transport while the quantity of a medication that can be incorporated into dissolving microneedles is limited. With skin permeation enhancers, concerns relating to cytotoxicity and irritation are common. Even though the use of ultrasound is exciting, this mode of delivery is also accompanied by challenges such as the design of a battery system that is potent enough to drive a low-frequency sonophoretic cymbal array, while still being portable enough to function as a wearable device. Although most researchers report enhanced drug delivery with the aforementioned methods, it is important to deliver therapeutically useful doses of these medications.

Design, Optimization and Characterization of a Transfersomal Gel Using Miconazole Nitrate for the Treatment of Candida Skin Infections

Miconazole nitrate (MIC) is an antifungal drug used for treatment of superficial fungal infections. However, it has low skin permeability. Hence, the objective of this study was to prepare miconazole nitrate using Transfersomes to overcome the barrier function of the skin. MIC Transfersomes were prepared using a thin lipid film hydration technique. The prepared Transfersomes were evaluated with respect to entrapment efficiency (EE%), particle size, and quantity of in vitro drug released to obtain an optimized formulation. The optimized formulation of MIC Transfersomes was incorporated into a Carbapol 934 gel base which was evaluated in comparison with a marketed product (Daktarin® cream 2%) for drug content, pH, spreadability, viscosity, in vitro permeation, and in vitro and in vivo antifungal activity. The prepared MIC Transfersomes had a high EE% ranging from (67.98 ± 0.66%) to (91.47 ± 1.85%), with small particle sizes ranging from (63.5 ± 0.604 nm) to (84.5 ± 0.684 nm). The in vitro release study suggested that there was an inverse relationship between EE% and in vitro release. The kinetic analysis of all release profiles was found to follow Higuchi's diffusion model. All independent variables had a significant effect on the dependent variables (p-values < 0.05). The prepared MIC transfersomal gel showed higher antifungal activity than Daktarin® cream 2%. Therefore, miconazole nitrate in the form of Transfersomes has the ability to penetrate the skin, overcoming the stratum corneum barrier.

Implementing Central Composite Design for Developing Transdermal Diacerein-Loaded Niosomes: Ex vivo Permeation and In vivo Deposition

BACKGROUND

Niosomes are surfactant-based vesicular nanosystems that proved their efficiency in transdermal delivery by overcoming skin inherent anatomic barrier; startum corneum. Central composite design is an efficient tool for developing and optimizing niosomal formulations using fewer experiments.

OBJECTIVE

The objective of this study was to prepare niosomes as a transdermal delivery system of diacerein using film hydration technique, employing central composite design, for avoiding its oral gastrointestinal problems.

METHODS

Three-level three-factor central composite design was employed for attaining optimal niosomes formulation with the desired characteristics. Three formulation variables were assessed: amount of salt in hydration medium (X1), lipid amount (X2) and number of surfactant parts (X3). DCNloaded niosomes were evaluated for entrapment efficiency percent (Y1), particle size (Y2), polydispersity index (Y3) and zeta potential (Y4). The suggested optimal niosomes were subjected to further characterization and utilized as a nucleus for developing elastic vesicles for comparative ex vivo and in vivo studies.

RESULTS

The values of the independent variables (X1, X2 and X3) in the optimal niosomes formulation were 0 g, 150 mg and 5 parts, respectively. It showed entrapment efficiency percentage of 95.63%, particle size of 436.65 nm, polydispersity index of 0.47 and zeta potential of -38.80 mV. Results of ex vivo permeation and skin deposition studies showed enhanced skin permeation and retention capacity of the prepared vesicles than drug suspension.

CONCLUSION

Results revealed that a transdermal niosomal system was successfully prepared and evaluated using central composite design which will result in delivering diacerein efficiently, avoiding its oral problems.