Ultrasonic sonication assisted in sol–gel stӧber and reverse microemulsion method for fabrication of silica nanoparticles and the potential application in agriculture

In this study, silica nanoparticles (SNPs) were uniformly fabricated by sol–gel Stӧber and reverse microemulsion (w/o) method under homogenisation by ultrasonic sonication at 40 kHz. As-prepared SNPs obtained robust and well-defined nanostructure with a relative standard deviation (RSD) of 0.9–3.6% for the sol–gel Stӧber method and 2.6–5.1% for the reverse microemulsion method. Practically, the examination of SNPs size was almost controlled by the ratio molar of NH₄OH and TEOS under sonication. The representative SNPs of 101.2 ± 2.8 nm were characterised by the zeta (ξ)-potential behaviour and average count range (ACR) upon ranging SNP concentrations. The results indicated that ξ-potential remained constant at about − 30 to − 31 mV under SNPs ranging from 10 to 500 μg/mL. The kilo-counts per second (kbps) value correlated linearly with increased SNPs concentrations. Also, the SiO₂ contents were distinguished by the determination of treated and untreated SNPs in plants (Broccoli) by HCl pre-treatment and subsequent thermolysis at 750 °C. It was obtained that SiO₂ content was undetectable in the untreated SNPs plant, whereas the amount of that was identified as about 0.108 mg/g in the treated plant. These findings revealed that as-prepared SNPs had uniform morphology, stability, and potential for further agricultural studies and implications.