Methods: AgNPs were synthesized by two methods: following a natural technique using silver nitrate (AgNO3) as precursor and Geranium maculatum extract as a reducing agent obtaining the (AgNPs-N); and using the chemical synthesis (AgNPs-Ch) using sodium borohydride as a reducing agent. The synthesized AgNPs were characterized by Infrared Spectroscopy (FT-IR), Raman-Dispersive Spectroscopy, UV-Vis Spectroscopy and Transmission Electron Microscopy (TEM). For the evaluation of the antifungal effect, it was culture Candida albicans ATCC-90026 (1x106) into agar plates. Discs of the sodium alginate Max Print Cyan® (MP) with/without nature and chemical AgNPs (1 mg/mL) were prepared: i) MP, ii) MP-AgNPs-N and iii) MP-AgNPs-Ch; (n=4). The discs were placed in the Candida albicans cultures and incubated at 37 °C for 24 h, then the size of the inhibition zones were measured. One-Way ANOVA (p<0.05) and Tukey test were applied. The test was performed in duplicate.
Results: Spectroscopy analyses showed the presence of characteristic peaks of the silver nanoparticles of the naturally and chemically synthesized AgNPs. Spherical silver nanoparticles were obtained with a diameter of 10-12 nm according to TEM observations for both kinds of AgNPs. Measurements of the inhibition zones of MP, MP-AgNPs-N and MP-AgNPs-Ch groups were: 0.45 ± 0.21, 1.03 ± 0.4 and 3.0 ± 0.2 mm respectively, showing significant statistical difference (p<0.05) among the alginate with chemically synthesized nanoparticles compared with the natural synthesized nanoparticles and the control group without silver nanoparticles.
Conclusions: The alginate added with AgNPs obtained by the chemical synthesis showed the highest growth inhibition of Candida albicans demonstrating broad antifungal effect. PAPIIT IN227411