Evolving nanotechnological trends in the management of mycotic keratitis

Recent Nanotechnological Trends in the Management of Microbial Keratitis

Microbial keratitis (MK) is a sight-threatening ocular disease that needs rapid diagnosis and treatment to prevent more serious outcomes. The broad-spectrum topical antimicrobial treatment is currently the main pharmacological approach for MK management, yet its efficacy is increasingly challenged by evolving antimicrobial resistance, including multidrug resistance. Also, the ocular surface presents numerous challenges for standard topical drug delivery. The failure and ineffectiveness of current therapies have necessitated the development of novel therapeutic strategies to manage MK. With advances in nanotechnology in the biomedical field, various nanomaterials can be employed to control MK. The primary determinants of nanoparticles' vast range of applications are their size, surface properties, and chemical makeup, which also happen to be the same elements that give rise to their poisonous and dangerous effects. In this study, we provide a perspective on the contact lens-associated corneal illnesses such as MK and explore how nanotechnology might help address this significant clinical issue. In addition, safety and toxicological concerns about the increasingly widespread use of contact lenses are also discussed.

A promising synthetic citric crosslinked β-cyclodextrin derivative for antifungal drugs: Solubilization, cytotoxicity, and antifungal activity

Effective antifungal therapy for the treatment of fungal keratitis requires a high drug concentration at the corneal surface. However, the use of natural β-cyclodextrin (βCD) in the preparation of aqueous eye drop formulations for treating fungal keratitis is limited by its low aqueous solubility. Here, we synthesized water-soluble anionic βCD derivatives capable of forming water-soluble complexes and evaluated the solubility, cytotoxicity, and antifungal efficacy of drug prepared using the βCD derivative. To achieve this, a citric acid crosslinked βCD (polyCTR-βCD) was successfully synthesized, and the aqueous solubilities of selected antifungal drugs, including voriconazole, miconazole (MCZ), itraconazole, and amphotericin B, in polyCTR-βCD and analogous βCD solutions were evaluated. Among the drugs tested, complexation of MCZ with polyCTR-βCD (MCZ/polyCTR-βCD) increased MCZ aqueous solubility by 95-fold compared with that of MCZ/βCD. The inclusion complex formation of MCZ/βCD and MCZ/polyCTR-βCD was confirmed by spectroscopic techniques. Additionally, the nanoaggregates of saturated MCZ/polyCTR-βCD and MCZ/βCD solutions were observed using dynamic light scattering and transmission electron microscopy. Moreover, MCZ/polyCTR-βCD solution exhibited good mucoadhesion, sustained drug release, and high drug permeation of porcine cornea ex vivo. Hen's Egg test-chorioallantoic membrane assay and cell viability study using Statens Seruminstitut Rabbit Cornea cell line showed that both MCZ/polyCTR-βCD and MCZ/βCD exhibited no sign of irritation and non-toxic to cell line. Additionally, antifungal activity evaluation demonstrated that all isolated fungi, including Candida albicans, Aspergillus flavus, and Fusarium solani, were susceptible to MCZ/polyCTR-βCD. Overall, the results showed that polyCTR-βCD could be a promising nanocarrier for the ocular delivery of MCZ.