Hybrid AgNPs/eggshell calcium carbonate particles and their antimicrobial efficiency
Creators: name: Sutapun, Wimonlak
name: Zin, Moe Ei Ei
name: Moolkaew, Pornpimol
name: Junyusen, Thiraporn
Publisher: name: Zenodo
Year: 2023
Subjects: Antimicrobial agent
Silver nanoparticles
Eggshell calcium carbonate
Silver loaded eggshell calcium carbonate
Food packaging
Co-precipitation

description: In this study, hybrid particles of AgNPs-loaded eggshell calcium carbonate (AgNPs/eCaCO<sub>3</sub>) were prepared<em> in situ</em> by precipitating the eggshell in the presence of freshly prepared AgNPs with a particle size of 10-30 nm. The hybrid particles were comparatively precipitated<em> in situ</em> at 25 °C and 35 °C using poly (sodium 4-styrenesulphonate) as a polyelectrolyte. The AgNPs/eCaCO<sub>3</sub> particles prepared at 25 °C had a spherical morphology with a mean diameter of 3.56 mm, and BET surface area of 85.08 m<sup>2</sup>/g. On the other hand, the particles prepared at 35 °C had a broader size distribution with a mean diameter of 3.19 mm, and a BET surface area of 79.25 m<sup>2</sup>/g. AgNPs-loaded commercial calcium carbonate particles (AgNPs/e=CaCO<sub>3</sub>) comparatively prepared at 35 °C were perfectly spherical with a mean diameter of 5.61 mm. At preparing temperature of 25 °C, the hybrid particles contain AgNPs of 0.78 wt% for AgNPs/eCaCO<sub>3</sub> and 3.20 wt% for AgNPs/CaCO<sub>3</sub>. The AgNPs/eCaCO<sub>3</sub> and AgNPs/CaCO<sub>3</sub> particles exhibited the same efficiency against bacteria extracted from beef with an average inhibition zone diameter of 7–10 mm according to the modified Kirby–Bauer disc diffusion assay depending on their concentration and beef source. Freshly prepared silver colloids showed comparatively poorer antimicrobial efficiency with an inhibition zone diameter around 7 mm.
description: Excel and image-related program.Funding provided by: Suranaree University of Technology<br>Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100004352<br>Award Number: Funding provided by: Thailand Science Research and Innovation<br>Crossref Funder Registry ID: http://dx.doi.org/10.13039/501100017170<br>Award Number: NRIIS #160344Funding provided by: National Science, Research, and Innovation Fund (NSRF)*<br>Crossref Funder Registry ID: <br>Award Number: NRIIS #160344
description: I. Particle diameter Field Emission Scanning Electron Microscopy (FESEM) was carried out on Carl Zeiss, Auriga to observe the particle morphology and particle size of AgNPs, eCaCO<sub>3</sub>, AgNPs/eCaCO<sub>3</sub>, and AgNPs/CaCO<sub>3</sub> using an accelerating voltage of 3.0 kV. Prior to the observation, each sample was coated using a gold sputter coater (Neo Coater) for 2 min. The diameter of the particles was measured from the SEM micrographs using an analysis software (Image J) and calculated by randomly selecting 200 particles. MATLAB R2022a was used to obtain the mean diameter, size distribution, and respective histogram. II. Inhibition zone diameters The digital images of the Inhibition zone diameters against beef-extracted bacteria obtained from AgNPs/eCaCO<sub>3</sub> and AgNPs/CaCO<sub>3</sub> were measured three times from a disc using ImageJ and an average made from three replica. The antimicrobial test was performed in triplicate and the average diameter of the inhibition zone with standard deviation was calculated.