Superenhanced Removal of Fungal Biofilms by Protease‐Functionalized Amphotericin B Nanocarriers

Abstract

A strong enhancement in the antifungal activity of amphotericin B (AmpB) encapsulated into shellac nanoparticles (NPs) surface functionalized with protease is reported. These AmpB‐loaded shellac NPs are fabricated by pH‐induced nucleation of aqueous solutions of shellac and AmpB in the presence of Poloxamer 407 (P407) as a steric stabilizer. The AmpB‐loaded shellac NPs are surface coated with the cationic protease Alcalase 2.4L FG. The performance of the AmpB‐encapsulated NPs against Candida albicans is evaluated. The AmpB‐loaded shellac NPs show a remarkable boost of their antifungal action compared to free AmpB when applied to C. albicans in both planktonic and biofilm forms. The surface functionalization with a cationic protease allows the NPs to adhere to the fungal cell walls, delivering AmpB directly to their membranes. Additionally, the hydrolyzing activity of the protease coating degrades the biofilm matrix, thus increasing the effectiveness of the encapsulated AmpB compared to free AmpB at the same concentration. The protease‐coated AmpB‐loaded shellac NPs show no greater toxicity to human adult keratinocyte cells (HaCaT) compared to the free AmpB. These AmpB nanocarriers demonstrat increased efficacy against C. albicans and can be potentially used to treat fungal biofilm infection in the clinic, for example, in recalcitrant chronic wounds.

Emerging nanotechnologies for targeting antimicrobial resistance

“…The same approach was found to work on fungal biofilms from Candida albicans, where the antifungal payload of AmphotericinB (AmpB) was loaded in shellac NPs. 155 Fig. 16F shows that after two-fold dilution of the stock AmpB-loaded shellac NP formulation and the free AmpB solution, there was a significant difference in the performance of these treatments.…”

“…16G. 155 5. The "benign-by-design" concept for antimicrobial nanocarriers Similar to the abuse of antibiotics, the commonly used formulations of antimicrobial nanoparticles use ubiquitous innocuous materials with relatively low biodegradability.…”

Enhanced clearing of Candida biofilms on a 3D urothelial cell in vitro model using lysozyme-functionalized fluconazole-loaded shellac nanoparticles

“…The design of the NPs used in the current work is based on shellac core and P407. The fabrication of the current NPs was studied in the work done by Al-Obaidy et al 1,2 and Weldrick et al 3 The optimal precipitation conditions for such shellac NPs were found at pH 5.5, which was used for our following experiments. The primary purpose of the current work is to check the possibility of using the biofilm-infected 3D urothelial cell model for testing antimicrobial nanotherapeutics; the NPs were tested for their ability to act as nanocarriers for the antifungal agent.…”

Enhanced Antimould Action of Surface Modified Copper Oxide Nanoparticles with Phenylboronic Acid Surface Functionality

“…Some of these cationic nanoparticle formulations rely on electrostatic attraction with the negatively charged cell walls of microbial cells. Recently, active nanocarriers of both antibiotic and antifungal agents were developed with protease coating that can digest their way through biofilms delivering their payload to the embedded microbial cells [27][28][29]. However, in antimould applications, the strategy of using solely such electrostatic binding to the mould can be challenging due to the presence of other anionic species in the hyphae immediate environment which can render the treatment ineffective.…”