Zetasizer nano zen3600

The particle size, polydispersity index (PDI) and zeta potential of the nanoemulsion at room temperature for 0 d and 35 d were determined based on dynamic light scattering (DLS) measurements made using a Zetasizer Nano ZEN3600 instrument (Malvern Instruments Ltd., Malvern, UK) equipped with a He-Ne laser (633 nm) at 25 °C and 90° collecting optics. All measurements were performed in triplicate. The size and zeta potential results are expressed in nm and millivolts, respectively [25 (link)].

The purity, absolute molecular weight (M_w), polydispersity (M_w/M_n), and radius of gyration (R_g) of OPP-D were determined by high-performance size-exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID, Wyatt Technology Co., Santa Barbara, CA, USA) on the basis of the previous method [9 (link)].
The hydrodynamic radius (R_h) of OPP-D was measured by using a dynamic light scattering (DLS, Zetasizer Nano, ZEN3600, Malvern Instruments, UK) according to a previous study with some modifications [25 (link)]. The sample was dissolved in 0.9% of NaCl aqueous solution. The determination was carried out at a constant temperature of 25 °C and at a scattering angle of 90°. The wavelength of the laser beam was set as 633 nm and the signal acquisition time was 5 s for 10 times.

Changes in the surface groups of the bacteria were indirectly measured by determining the surface charge of the fresh and rehydrated freeze-dried Lp. plantarum HAC03 cells with or without the food additives incorporated into the mix. The assay was carried out by mixing the previously rehydrated bacteria with 9 mL of double-distilled water (DDW) at pH 2.0 to reach a final concentration of 1 × 10⁸ CFU/mL. The pH was measured and corrected to pH 2.0 by adding 0.1 N HCl or 0.1 N NaOH, and 800 μL samples were loaded in DTS1070 cuvettes. The samples were measured on a Zetasizer Nano ZEN 3600 after 2 min equilibration time (Malvern Panalytical, Malvern, UK) and the Smoluchowski model was used to convert electrophoretic mobility data to zeta potential values [34 (link)], which were considered as the average of three reads.

Buspirone NDS was analyzed using a Malvern Zetasizer-nano, ZEN 3600, Malvern Instruments, Malvern, UK. The system was diluted 1:500 with suitable diluent one hour prior to measurement. Three batches of each system were tested. Each batch was analyzed by intensity, three times, at 25 °C. The duration and the set position of each measurement were fixed automatically by the apparatus.

Submicron particle size analysis was performed using a Zetasizer nano (ZEN 3600, Malvern Instruments, UK). Measurements were made at 25°C at a scattering angle of 90°. The mean particle size and polydispersity index were determined in a single run while the zeta potential was similarly determined by phase analysis light scattering (PALS) using the same instrument.

Size distribution and polydispersity index (PDI) were determined by Dynamic Light Scattering (DLS) using a Zetasizer Nano ZEN3600 (Malvern Instruments Ltd, Worcestershire, UK) equipped with a 633 nm He–Ne laser. Particles were dissolved in PBS to a final concentration of 1 mg/ml and filtered 0.22 µm. A particle refractive index (RI) of 1590 and an absorption value of 0.01 were assumed and a detection angle of 173° was used.

The lipids DLPC and DLPG, and POPC and POPG used for liposome construction were from Avanti Polar Lipids. The lipids were weighted up, dissolved in chloroform–methanol (2:1, v/v), dried under a nitrogen stream and placed under vacuum overnight. The resulting film was hydrated to 10 mg mL^–1 total lipid concentration in 10 mM phosphate buffer, pH 7.4. The suspension was then extensively vortexed, sonicated (30 °C) and extruded (15 times) through polycarbonate filters (0.05 μm) using a hand-held extruder (Avanti Polar Lipids) to give a clear solution containing small unilamellar vesicles (SUV), which were analysed (50 nm) by photon correlation spectroscopy using a Zetasizer Nano (ZEN3600, Malvern Instruments, UK) following the re-suspension of vesicles to a final concentration of 1 mg mL⁻¹. DLS batch measurements were carried out in a low-volume disposable cuvette at 25 °C. Hydrodynamic radii were obtained through the fitting of autocorrelation data using the manufacture’s software, Dispersion Technology Software (DTS version 5.10).