Synthesis, Characterization, and Antifungal Activity of Silver Nanoparticles Embedded in Pullulan Matrices.

Olga Burduniuc,Sergiu Coseri,Andra-Cristina Bostanaru,Gabriela Biliuta,Mihai Mares

doi:10.3390/ma14227041

Abstract

Steady developments made in nanotechnology-based products have facilitated new perspectives for combating drug-resistant fungi. Silver nanoparticles represent one of the most attractive nanomaterials in biomedicine due to their exclusive optical, electromagnetic, and catalytic properties and antifungal potency compared with other metal nanoparticles. Most studies show that the physicochemical parameters affecting the antifungal potential of AgNPs include the shape, size, surface charge, and concentration and colloidal state. For the present study, pullulan (P) and its oxidized counterpart (PO) have been selected as matrices for the silver nanoparticles’ generation and stabilization (AgNPs). The TEMPO (2,2,6,6-tetramethylpiperidin-1-yl radical)–sodium hypochlorite–sodium bromide system was used for the C6 selective oxidation of pullulan in order to introduce negatively charged carboxylic groups in its structure. The structure and morphology of the synthesized AgNPs were analyzed using FTIR and EDX. The main objective of this study was to elucidate the antifungal activity of AgNPs on the clinical yeasts isolates and compare the performance of AgNPs with the conventional antifungals. In this study, different concentrations of AgNPs were tested to examine antifungal activity on various clinical isolates.

Highlights

Fungal diseases have been underappreciated over the last few decades, which resulted in a significant impact on human health
Despite some advances in treatment, invasive fungal infections persist as a common cause of morbidity and mortality in immunocompromised patients, especially affecting high-risk patients [10]
Most studies were focused on the synthesis of AgNPs with controlled size and shape, and a diversity of specific synthetic protocols have been proposed, including chemical, physical, or biological methods [18]

Summary

Introduction

Fungal diseases have been underappreciated over the last few decades, which resulted in a significant impact on human health. Most of the pathogenic fungi are opportunistic and cause disease under immunocompromised conditions such as long-term antibiotics administration, organ transplantation, cancer, treatments involving steroids, or HIV infections [4,5,6,7,8,9]. Silver nanoparticles (AgNPs) have attained a primary role with the most appealing nanomaterials in biomedicine due to their large range of activities and their unique physical and chemical properties [15,16]. Most studies were focused on the synthesis of AgNPs with controlled size and shape, and a diversity of specific synthetic protocols have been proposed, including chemical, physical, or biological methods [18]

Objectives

Methods

Results

Conclusion