Zeta pals potential analyzer

For the analysis of the Zeta Potential, 10 mg of each encapsulated were dispersed in 4 mL of distilled water, then disposed in acrylic cuvettes with lateral electrodes. A total of 10 runs, 1 minute each, were performed in the NanoBrook ZetaPlus potential Analyzer, coupled with the Software Brookhaven Instruments–PALS Zeta potential Analyzer. The experiment was performed in triplicate.

Particle size distribution was assessed using a particle size analyzer (Brookhaven Instruments Corporation, operated by particle sizing v.5 Brookhaven instruments software, Holtsville, NY, USA). The qualitative particle properties were determined in PH-SIDI and PH/CHL-SIDI in solution, in external and internal NP coating and NP-secondary coating I and II layers in powder. The dried particles were dispersed in ethanol 99% to avoid probable agglomeration and sonicated (SOLTEC, SONICA 2200MH S360Hz, Milano, Italy) for 7 min to eliminate the agglomeration and deformation of external layer. In the case of PH-SIDI and PH/CHL-SIDI solutions, the small droplets were dispersed in ethanol 99% and sonicated for more 7 min to avoid aggregation of lipid colloids. The particle size was characterized by mean size in volume and number, obtained in six runs of 1 min at 21 °C. The particles surface charges were obtained with ZetaPLAS (Zeta Potential Analyzer, Brookhaven Instruments Corporation, operated by the PALS Zeta Potential Analyzer v.5 Brookhaven Instruments software, Holtsville, NY, USA), after 6 runs of 30 s at 21 °C. All samples were analyzed regarding individual parameters in separated runs.

The size distribution of the rapamycin PFC nanoparticles was evaluated by dynamic light scattering (Brookhaven Instruments Corp., Holtsville, NY, USA). The surface charge of the nanoparticles was determined using a PALS Zeta Potential Analyzer (Brookhaven Instruments Corp.). Data were collected in the mode of phase-analysis light-scattering (PALS) after the solution was equilibrated at 25 °C. All samples were diluted in MilliQ water.

UV–Vis spectra of the samples were recorded at 25 °C using a Jasco V-670 spectrophotometer (Jasco Europe S.R.L., Milano, Italy), using 10 mm path length quartz cuvettes. As a first approximation, the particle size was determined directly from UV–Vis spectra using the tabulated theoretical data of uncoated spherical gold nanoparticles in water described in Haiss et al. [72 (link)]. The size of the different AuNPs was qualitatively confirmed by means of TEM. The surface charge of AuNP samples was measured in suspension of 50 μg/mL in water at 25 °C using a phase amplitude light scattering (PALS) zeta potential analyzer (Brookhaven Instruments Corporation, Hotsville, NY, USA). The Smoluchowski approximation [73 (link)] was fitted to 15 cycles of electrophoretic mobility (EPM) measurements and 10 replicates were obtained for each sample to estimate the mean and SD. Dynamic light-scattering (DLS) measurements were carried out at room temperature and at a scattering angle of 90°, using a 3D LS spectrometer (LS instruments AG, Fribourg, Switzerland) equipped with a 21 mW HeNe laser (632.8 nm). Data was collected over 4 min, and five independent correlation functions were measured. The corresponding correlation functions were analyzed using the constrained regularized cumulant method [74 (link)].

The size distributions of the PFC nanoparticles were evaluated by dynamic light scattering (Brookhaven Instruments Corp., Holtsville, NY, USA). The surface charges of the nanoparticles, indicated by zeta-Potential values, were determined with a PALS Zeta Potential Analyzer (Brookhaven Instruments Corp.). Data were collected in the mode of phase-analysis light-scattering (PALS) after the solution was equilibrated at 25 °C. All samples were diluted in MilliQ water (Merck, Rachway, NJ, USA).

The surface morphology of raw vitexin and vitexin nanoparticles were observed by SEM (Quanta 200, FEI Company, Eindhoven, The Netherlands). The MPS of vitexin nanosuspensions and the particle size distribution (PSD) of lyophilized powder dispersed in deionized water were measured with dynamic light scattering (DLS) (Zeta-PALS, Brookhaven Instruments Corp., Holtsville, NY, USA). The zeta potential values of vitexin particles obtained through ASP and vitexin nanosuspensions prepared by ASP-HPH techniques were measured using a PALS Zeta Potential Analyzer (Brookhaven Instruments Corp., Holtsville, NY, USA) with the samples diluted in deionized water to approximately 1 mg/mL for each measurement. All measurements were made in triplicate.

Particle size, poly-dispersity index (PDI), and zeta (ζ) potential of SO-TSO microcapsules were determined using a PALS Zeta potential analyzer (Brookhaven instruments corp, Holtsville, NY, USA). Microcapsule samples were suitably diluted in ethanol and measured at 25 °C for size, PDI, and ζ potential.