Malvern nano zs instrument

SiO₂ NPs were obtained from NaBond Technologies Co., Ltd. (Shenzhen, China). The synthesis and characterization of NPs were described in detail in our previous paper [24 (link)]. Briefly, amorphous SiO₂ NPs were synthesized by the reactive laser ablation method and homogenized in Milli-Q water, ultrasonicated, and sterilized by autoclaving at 121 °C for 15 to 20 min. The NPs are spherical in shape and have a mean size of less than 10 nm. The NPs characteristics were analyzed using transmission electron microscopy (TEM) (FEI, Hillsboro, OR, USA), energy-dispersive X-ray spectroscopy (EDX) (Oxford Instruments, Abingdon, UK), and zeta potential analyses. The SiO₂ NPs were dispersed in distilled water at a concentration of 250 μg/mL. Three small drops (10 µL) of this diluted mixture were added consecutively on top of a pure carbon film copper grid (Ted Pella, Inc., Redding, CA, USA). Each time, the excess was carefully removed using filter paper. The sample was analyzed in bright field mode using a Tecnai F20 G² TWIN crio- TEM from (FEI, Hillsboro, OR, USA) at an acceleration voltage of 200 kV. The zeta potential of SiO₂ NPs (62.5 μg/mL) in ultrapure Milli-Q water was assessed using a Malvern Nano-ZS instrument (Malvern Instruments, Malvern, Worcestershire, UK). The measurements were performed in triplicate at 25 °C using the refractive index of 1.46.

The Zetasizer “Malvern Nano ZS instrument, Southborough, MA” was used for appraising the surface charges (zeta potential) and distribution of nanoparticles/nanocomposites Ps, using the Dynamic Light Scattering (DLS) technique, for synthesized NCt, NCt/RA, NCt/RA/SeNPs and SeNPs [26 ]. The dissolved samples in DW were sonicated for 35 min prior to investigation, the hydrodynamic diameters and the zeta potentials of screened particles were measured in backscatter configuration (θ = 173°) at λ = 633 nm laser wavelength. The attained data were analyzed using Zetasizer software V. 7.03.

In 5 mL of purified water, 5 mg of lyophilized liposomes was redispersed, and to reduce the inter-particle aggregation, the solution was sonicated for 5 min. The average hydrodynamic diameter (Z-average), surface charge (zeta potential), and polydispersity index (PDI) of the liposomes were analyzed in folded capillary cells using the Malvern nano ZS instrument (Malvern Instruments, Worcestershire, UK). The temperature and refractive index of the apparatus were set at 25 °C and 1.445, respectively, and the total number of scans was 17. The measurements were repeated in triplicate, and the average value of each was evaluated. The standard acceptable ranges for the Z-average, zeta potential, and PDI are 100–200 nm, ±30 to 40 (mV), and 0.0–0.03, respectively.

The zeta potential and size of nanoparticles were measured via dynamic light scattering [40 (link)] with the Malvern Nano ZS instrument (Malvern Instruments Ltd., Worcestershire, UK), as described earlier [17 (link),27 (link),41 (link)]. Each measurement was repeated three times. The average zeta potential measurement error (standard deviation) was 5 mV maximum.

The characterization of the NPs started by analyzing the average hydrodynamic diameter (Z-average), polydispersity index (PDI), and the ZP. These parameters were analyzed after redispersing the freeze-dried samples in purified water, then placing the suspensions in folded capillary cells using a Malvern Nano ZS instrument (Malvern Instruments, Worcestershire, UK). The temperature and refractive index of the apparatus were set at 25 °C and 1.755, respectively, and the total number of scans was 17. For the analysis, aliquots of the NPs colloidal solution were sampled before and after the incubation with the chitosan. Then, they were dispersed in ultrapure water (1:200 v/v) and placed in a cuvette to check the size, PDI, and ZP changes. The measurements were performed in triplicate, and the data were reported as means ± SD.