Comparison of Inhibitory Effect of Colloidal Silver and Silver Nanoparticle against Propionibacterium acnes bacteria

Published: 28 June 2024| Version 1 | DOI: 10.17632/kk7r9j99pk.1
suparno suparno, Eka Sentia Ayu Lestari, Kapabihi Kapabihi, Deby Grace


The paper describes a comparison between Colloidal Silver (CS) and Silver Nanoparticles (SNP) in terms of production technique, absorption peak wavelength, particle size, clear zone diameter, and the duration before the emergence of resistance in Propionibacterium acnes. CS was produced using an electrolysis technique employing a pair of slab electrodes made from 99.95% silver with some additional bromide (AgBr). Observations of silver concentration as a function of time were conducted over 2 hours at a voltage difference of 24 Volts. The SNP was produced using a synthesis technique that involved mixing silver nitrate (AgNO3) and trisodium citrate (Na3C6H5O7). Both CS and SNP samples were prepared at concentrations of 10 ppm and 30 ppm. Absorption wavelength observations were performed using a UV-visible spectrophotometer and found that the absorption peak wavelengths of CS and SNP were 437 nm and 425 nm, respectively. The differences in these absorption peak wavelengths were discussed in the paper. Particle size measurements were conducted using dynamic light scattering, revealing that the particle diameter of CS is significantly larger than that of SNP. These size measurement differences were also properly discussed. The assessment of antibacterial inhibition was carried out using the Kirby-Bauer disk diffusion method. The clear zone diameters of CS and SNP were compared to each other and to chloramphenicol as a positive control. The comparison also included the duration before the emergence of bacterial resistance for CS, SNP, and chloramphenicol.


Steps to reproduce

The production of SNP simply done using electrolysis technique at 24 Volts voltage difference between the electrodes which were submerged into 400ml of distilled water. The data of SNP concentration (ppm) vs time (minute) were collected once in 10 minutes for a total of two hours resulted in maximum concentration of 31 ppm. This was then diluted to 10 ppm and 30ppm. The production of CS was done by synthesis technique. This was done by preparing a stock sample of AgNO3 (10mM with a volume of 1 liter) by mixing 1079mg of AgNO3 with water to a total volume of 1 liter which resulted in 1079ppm. The dilution was done by preparing 2 ml of this stock sample and 2 ml of the stabilizer and mixed them with 36ml of water to obtain CS of 54ppm. This was then once again diluted to get 10ppm and 30ppm by using C1V1=C2V2 equation. Some samples were sent to UV-visible laboratory and some were sent to Particle Size Analyzer laboratory for the determination of absorption peak wavelength and particle size respectively. The observation of antibacterial bacterial activity of CS and SNP were done in Microbiology laboratory.


Universitas Negeri Yogyakarta Program Pascasarjana


Colloidal Nanomaterials, Nanomedicine