Voriconazole incorporated nanofiber formulations for topical application: preparation, characterization and antifungal activity studies against Candida species

Gingerol containing polymeric nanofibers: a healing touch for accelerated wound recovery

OBJECTIVE

In the current research, 6-gingerol (GA)-loaded nanofiber drug delivery system were developed, and their potential usage in wound healing was evaluated.

SIGNIFICANCE

This study investigates the effectiveness of nanofibrous membranes composed of sodium alginate (SA), poly(vinyl alcohol) (PVA), and 6-gingerol (GA) as delivery systems for anti-inflammatory agents in the context of wound dressings.

METHODS

GA-loaded SA/PVA nanofiber was prepared using electrospinning. In vitro characterization of this nanofiber included the examination of comprehensive in vitro characterization, anti-inflammatory and antioxidant activities, cytotoxicity, a scratch tes and in vivo skin test.

RESULTS

GA was extracted from Zingiber officinale, and its successful isolation was confirmed through analyses such as H-NMR, C-NMR. Then GA was electrospuned into the SA/PVA nanofibers, and scanning electron microscopy (SEM) imaging revealed that the fiber diameters of the formulations ranged between 148 nm and 176 nm. Anti-inflammatory and antioxidant studies demonstrated that the effectiveness of GA increased with higher doses; however, this increase was accompanied by decreased cell viability. In vitro release studies revealed that GA exhibited a burst release within the first 8 h, followed by a controlled release, reaching completion within 24 h. Within the scope of in vitro release kinetics, release data are mathematically compatible with the Weibull model with high correlation. The scratch test results indicated that TB2 (%1 GA) promoted epithelialization. Furthermore, it was determined that TB2 (%1 GA) did not cause any irritation.

CONCLUSIONS

As a result, TB2 shows promise as a formulation for wound dressings, offering potential benefits in the field of wound care.

Fabrication of gelatin coated polycaprolactone nanofiber scaffolds co-loaded with luliconazole and naringenin for treatment of Candida infected diabetic wounds

The current study focuses on the development of gelatin-coated polycaprolactone (PCL) nanofibers co-loaded with luliconazole and naringenin for accelerated healing of infected diabetic wounds. Inherently, PCL nanofibers have excellent biocompatibility and biodegradation profiles but lack bioadhesion characteristics, which limits their use as dressing materials. So, coating them with a biocompatible and hydrophilic material like gelatin can improve bioadhesion. The preparation of nanofibers was done with the electrospinning technique. The solid state characterization and in-vitro performance assessment of nanofibers indicate the formation of uniformly interconnected nanofibers of 200-400 nm in diameter with smooth surface topography, excellent drug entrapment, and a surface pH of 5.6-6.8. The antifungal study showed that the nanofiber matrix exhibits excellent biofilm inhibition activity against several strains of Candida. Further, in-vivo assessment of nanofiber performance on C. albicans infected wounds in diabetic rats indicated accelerated wound healing efficacy in comparison to gauge-treated groups. Additionally, a higher blood flow and rapid re-epithelialization of wound tissue in the treatment group corroborated with the results obtained in the wound closure study. Overall, the developed dual-drug-loaded electrospun nanofiber mats have good compatibility, surface properties, and excellent wound healing potential, which can provide an extra edge in the management of complex diabetic wounds.

Nanotherapeutics for the delivery of antifungal drugs

The treatment of fungal infections is challenging with high death rates reported among immunocompromised patients. The currently available antifungals suffer from poor bioavailability and solubility, pharmacokinetics, and drug resistance, with limited cellular uptake. The clinical pipeline of new antifungals is dry. The incorporation of antifungal drugs into polymer-based nanocarriers to form nanotherapeutics is a promising approach to enhance the therapeutic outcomes of the available antifungal drugs. This review summarizes different polymer-based nanotherapeutics strategies that have been explored for the delivery of antifungals, resulting in enhanced therapeutic outcomes, such as improved pharmacokinetics, targeted/sustained delivery, prolonged drug circulation, retention of the drugs at the localized site of action, and overcoming drug resistance when compared with the free antifungal drugs.

Evolving Trends in Nanofibers for Topical Delivery of Therapeutics in Skin Disorders

Nanotechnology has yielded nanostructure-based drug delivery approaches, among which nanofibers have been explored and researched for the potential topical delivery of therapeutics. Nanofibers are filaments or thread-like structures in the nanometer size range that are fabricated using various polymers, such as natural or synthetic polymers or their combination. The size or diameter of the nanofibers depends upon the polymers, the techniques of preparation, and the design specification. The four major processing techniques, phase separation, self-assembly, template synthesis, and electrospinning, are most commonly used for the fabrication of nanofibers. Nanofibers have a unique structure that needs a multimethod approach to study their morphology and characterization parameters. They are gaining attention as drug delivery carriers, and the substantially vast surface area of the skin makes it a potentially promising strategy for topical drug products for various skin disorders such as psoriasis, skin cancers, skin wounds, bacterial and fungal infections, etc. However, the large-scale production of nanofibers with desired properties remains challenging, as the widely used electrospinning processes have certain limitations, such as poor yield, use of high voltage, and difficulty in achieving in situ nanofiber deposition on various substrates. This review highlights the insights into fabrication strategies, applications, recent clinical trials, and patents of nanofibers for different skin disorders in detail. Additionally, it discusses case studies of its effective utilization in the treatment of various skin disorders for a better understanding for readers.

Preparation, optimization, and in vitro-in vivo evaluation of sorafenib-loaded polycaprolactone and cellulose acetate nanofibers for the treatment of cutaneous leishmaniasis

The most common form of leishmaniasis is cutaneous leishmaniasis (CL). The major difficulties in the treatment of leishmaniasis include emergence of resistance, toxicity, long-term treatment, and the high cost of the current drugs. Although the therapeutic effect of sorafenib (SF) has been demonstrated in both in vitro and in vivo models of Leishmania infection, the therapeutic applications are limited due to severe drug-related toxicity; this is, in turn, due to non-specific distribution in the body. Thus, topical delivery has the advantage of the site directed delivery of SF. This research study evaluated SF-loaded hybrid nanofibers (NFs) which were composed of polycaprolactone (PCL) and cellulose acetate (CA) for the CL topical treatment. Accordingly, SF-loaded hybrid NFs were prepared using the electrospinning method. Formulation variables including total polymer concentration, drug/polymer ratio, and CA concentration were optimized using a full factorial design. The prepared SF-loaded NFs were then characterized for morphology, diameter, encapsulation efficiency (EE)%, drug loading (DL) %, and percentage of release efficiency during a 24-h period (RE_24h%); the mechanical characteristics were also considered. The physical state of the drug in the optimized NF was evaluated by the X-ray diffraction analysis. Finally, its in vivo efficacy was determined in L. major-infected mice. The optimized formulation had a smooth, cylindrical, non-beaded shape fiber with a diameter of 281.44 nm, EE of 97.96%, DL of 7.48%, RE of 51.05%, ultimate tensile strength of 1.08 MPa, and Young's moduli of 74.96 MPa. The XRD analysis also demonstrated the amorphous state of SF in NF. Further, the in vivo results displayed the higher anti-leishmanial activity of the SF-loaded hybrid NF by efficiently healing lesion and successfully reducing the parasite burden. This, thus, indicated the potential of the clinical capability of the SF-loaded hybrid NF for the effective treatment of CL.

Nanotechnology-Based Approaches for Voriconazole Delivery Applied to Invasive Fungal Infections

Invasive fungal infections increase mortality and morbidity rates worldwide. The treatment of these infections is still limited due to the low bioavailability and toxicity, requiring therapeutic monitoring, especially in the most severe cases. Voriconazole is an azole widely used to treat invasive aspergillosis, other hyaline molds, many dematiaceous molds, Candida spp., including those resistant to fluconazole, and for infections caused by endemic mycoses, in addition to those that occur in the central nervous system. However, despite its broad activity, using voriconazole has limitations related to its non-linear pharmacokinetics, leading to supratherapeutic doses and increased toxicity according to individual polymorphisms during its metabolism. In this sense, nanotechnology-based drug delivery systems have successfully improved the physicochemical and biological aspects of different classes of drugs, including antifungals. In this review, we highlighted recent work that has applied nanotechnology to deliver voriconazole. These systems allowed increased permeation and deposition of voriconazole in target tissues from a controlled and sustained release in different routes of administration such as ocular, pulmonary, oral, topical, and parenteral. Thus, nanotechnology application aiming to delivery voriconazole becomes a more effective and safer therapeutic alternative in the treatment of fungal infections.

Statistical optimization of voriconazole nanoparticles loaded carboxymethyl chitosan-poloxamer based in situ gel for ocular delivery: In vitro, ex vivo, and toxicity assessment

The research study reflects the development of novel voriconazole (VCZ) loaded nanoparticles (NPs) for prolonged delivery for the management of ocular diseases. The in situ ophthalmic gel was prepared by incorporating NPs into carboxymethyl chitosan (CMCh) and poloxamer. The central composite design was used to optimize the process for the preparation of nanoparticles by the o/w solvent evaporation method. The developed nanoparticles were evaluated for the encapsulation efficiency (89.6 ± 1.2%), particle size (219.3 ± 1.8 nm), polydispersity index (PDI, 0.1), zeta potential (- 21.1 ± 1.12 mV), saturation solubility, DSC study, and drug release. The etherification process grafts carboxyl surface functional groups, on chitosan, and was confirmed by FTIR and NMR studies. The developed CMCh-poloxamer based gelling system was found to be clear and transparent with gelation temperature varying from 33 to 40 °C. The nanoparticle-loaded gel containing CMCh demonstrated enhanced antifungal activity against Candida albicans. The optimized batch containing CMCh showed improved mucoadhesion by 2.86-fold compared to VCZ nanosuspension. The drug release was prolonged up to 8 h with an ex vivo study suggesting the enhanced permeation across goat cornea estimated via fluorescent microscope. The hen's egg chorioallantoic membrane study revealed that the formulation was non-irritant and tolerated by the chorioallantoic membrane. The present study concludes that the VCZ loaded nanoparticulate in situ ophthalmic gel using CMCh may act as a potential alternative for traditional eye drops.

Optimization of the Micellar-Based In Situ Gelling Systems Posaconazole with Quality by Design (QbD) Approach and Characterization by In Vitro Studies

Background: Fungal ocular infections can cause serious consequences, despite their low incidence. It has been reported that Posaconazole (PSC) is used in the treatment of fungal infections in different ocular tissues by diluting the oral suspension, and successful results were obtained despite low ocular permeation. Therefore, we optimized PSC-loaded ocular micelles and demonstrated that the permeation/penetration of PSC in ocular tissues was enhanced. Methods: The micellar-based in situ gels based on the QbD approach to increase the ocular bioavailability of PSC were developed. Different ratios of Poloxamer 407 and Poloxamer 188 were chosen as CMAs. Tsol/gel, gelling capacity and rheological behavior were chosen as CQA parameters. The data were evaluated by Minitab 18, and the formulations were optimized with the QbD approach. The in vitro release study, ocular toxicity, and anti-fungal activity of the optimized formulation were performed. Results: Optimized in situ gel shows viscoelastic property and becomes gel form at physiological temperatures even when diluted with the tear film. In addition, it has been shown that the formulation had high anti-fungal activity and did not have any ocular toxicity. Conclusions: In our previous studies, PSC-loaded ocular micelles were developed and optimized for the first time in the literature. With this study, the in situ gels of PSC for ocular application were developed and optimized for the first time. The optimized micellar-based in situ gel is a promising drug delivery system that may increase the ocular permeation and bioavailability of PSC.

Formulation Development, Characterization and Antifungal Evaluation of Chitosan NPs for Topical Delivery of Voriconazole In Vitro and Ex Vivo

This study aims to develop chitosan-based voriconazole nanoparticles (NPs) using spray-drying technique. The effect of surfactants and polymers on the physicochemical properties, in vitro release, and permeation of NPs was investigated. The prepared NPs containing various surfactants and polymers (e.g., Tween 20 (T20), Tween 80 (T80), sodium lauryl sulfate (SLS), propylene glycol (PG), and Polyethylene glycol-4000 (PEG-4000)) were physiochemically evaluated for size, zeta potential, drug content, percent entrapment efficiency, in vitro release, and permeation across rats' skin. A Franz diffusion cell was used for evaluating the in vitro release and permeation profile. The voriconazole-loaded NPs were investigated for antifungal activity against Candida albicans (C. albicans). The prepared NPs were in the nano range (i.e., 160-500 nm) and positively charged. Images taken by a scanning electron microscope showed that all prepared NPs were spherical and smooth. The drug content of NPs ranged from 75% to 90%. Nanoparticle formulations exhibited a good in vitro release profile and transport voriconazole across the rat's skin in a slow control release manner. The NPs containing SLS, T80, and PG exhibited the best penetration and skin retention profile. In addition, the formulation exhibited a potential antifungal effect against C. albicans. It was concluded that the development of chitosan NPs has a great potential for the topical delivery of voriconazole against fungal infection.

Nanofiber as a novel vehicle for transdermal delivery of therapeutic agents: challenges and opportunities

Background

Transdermal delivery of drugs is a quite challenging task for pharmaceutical scientists. The transdermal route is preferred over the oral route due to various advantages like avoidance of the first-pass effect, non-invasiveness, and high patient compliance. Therefore, it is necessary to develop an effective carrier system that enables the effective passage of the drug through the dermal barrier.

Main body of abstract

Various novel drug delivery systems are used to enhance the permeation of a variety of drugs through the skin barrier. Researchers around the globe have explored nanofibers for the transdermal delivery of various therapeutic agents. Nanofibers are designed to have a high concentration of therapeutic agents in them promoting their flux through various skin layers. Polymeric nanofibers can be explored for the loading of both hydrophilic and lipophilic drugs. Biopolymer-based nanofibers have been also explored for transdermal delivery. They are capable of controlling the release of therapeutic agents for a prolonged time.

Short conclusion

The literature presented in this review paper provides significant proof that nanofibers will have an intense impact on the transdermal delivery of different bioactive molecules in the future.

Graphic abstract

Diltiazem-loaded electrospun nanofibers as a new wound dressing: fabrication, characterization, and experimental wound healing

Calcium channel blockers such as diltiazem have recently been investigated for their wound-healing potential. The aims of this study were to fabricate diltiazem-loaded nanofibers for a new wound dressing and investigate their beneficial properties for wound healing. Nanofibers were electrospun using polyvinyl alcohol solution containing 0, 2 or 4% diltiazem. Fibers were characterized in terms of physicochemical properties, drug release and fibroblast viability, and in animal wound healing assays. Compared to other formulations, nanofibers containing 4% diltiazem showed thin fiber size (152.7 nm), high porosity (88.4%), high swelling (110.4%), low water contact angle (29.1°) and little weight loss (17.3%). Drug release from 4%-diltiazem nanofibers showed good fit to a Korsmeyer-Peppas model, suggesting a non-Fickian release mechanism (R ² = 96%, n = 0.52). In vitro, 4%-diltiazem mats were not cytotoxic and enhanced fibroblast proliferation by 263% after 5 days of treatment compared to control. In vivo, wounds treated with this mat for 14 days showed the smallest size (14.7%) and better histopathologic characteristics compared to other wounds. The 4%-diltiazem mat also demonstrated significant antioxidant activity by reducing tissue MDA and nitrite levels by 63 and 59% compared to normal saline. The findings support the eligibility of this novel wound dressing for additional clinical research.