Biosynthesis and Characterization of Copper Nanoparticles Using a Bioflocculant Produced by a Yeast Pichia kudriavzevii Isolated from Kombucha Tea SCOBY

• Published in: Applied nano 2023-08, Vol.4 (3), p.226-239
• Main Authors: Tsilo, Phakamani H., Basson, Albertus K., Ntombela, Zuzingcebo G., Dlamini, Nkosinathi G., Pullabhotla, Rajasekhar V. S. R.
• Format: Article
• Language: English
• Subjects: Amines; bioflocculant; Biosynthesis; characterization; Chemical reduction; Chemical synthesis; Copper; copper nanoparticles; Copper oxides; Fourier transforms; Functional groups; Infrared spectroscopy; Kombucha tea SCOBY; Nanomaterials; Nanoparticles; Pichia kudriavzevii; Scanning electron microscopy; Surface plasmon resonance; Toxicity; Transmission electron microscopy; X-ray diffraction; Yeast
• ISSN: 2673-3501; 2673-3501
• DOI: 10.3390/applnano4030013

Over recent years, the ‘green’ chemistry approach to synthesizing nanoparticles has made significant developments. Because of their unique features, nanoparticles have received a lot of attention. The use of a bioflocculant to promote the environmentally friendly synthesis of copper nanoparticles is described in this paper. Copper nanoparticles were biosynthesized using bioflocculant which was produced from a yeast, Pichia kudriavzevii. The chemical reduction approach was used to synthesize copper nanoparticles (CuNPs) using a bioflocculant as a capping agent. Characterization of the as-synthesized copper nanoparticles was conducted using Fourier transform infrared (FT-IR) spectroscopy, UV-visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX). The FT-IR spectra revealed characteristic peaks at 3267, 2956, 1656, 1059, and 511 cm−1 for the bioflocculant, while for the bioflocculant passivated CuNPs, the characteristic peaks were at 3482 (-OH), 3261, 1640, 1059, 580, and 519 cm−1 (Cu-O). These peaks revealed that functional groups such as hydroxyls, amines, and copper oxide bonds were present. The UV-Vis analysis showed surface plasmon resonance (SPR) at an absorbance range of 500–600 nm, with peak maxima at 555 and 575 nm for the as-synthesized CuNPs. The XRD pattern revealed planes such as (200) and (220) at 2θ = 43 and 52°, and the particle size (30 nm) was determined by the Debye–Scherrer equation. The transmission electron microscopy analysis revealed a spherical-shaped particle with an average size of 20 nm. The EDX analysis of the as-synthesized CuNPs revealed the presence of the element Cu, which was not present in the EDX image of the bioflocculant used in the synthesis of the CuNPs; this indicated the success of biosynthesis.