Zetasizer nano zs instrument

TEM was used to observe the morphology and mesostructure of the NPs. The samples were prepared and dried by dropping them onto a carbon-coated copper grid and then observing them on a JEOL JSM-1200 EX II transmission electron microscope operated at 100 kV. Total surface areas and average pore diameters were determined by measuring the nitrogen adsorption–desorption isotherm on a Micrometerics ASAP 2010 apparatus and calculation by the BET and Barrett–Joyner–Halenda (BJH) methods. The hydrodynamic diameters of the NPs in water, PBS, serum-free, and culture medium supplemented with 10% fetal bovine serum (FBS) were assessed using DLS on a Malvern Zetasizer Nano ZS instrument. Zeta potential measurements were performed on a Malvern Zetasizer Nano ZS instrument by determining the electrophoretic mobility and applying Henry’s equation.

A previously optimized method for the preparation of nanoemulsions was employed [14 (link)]. The nanoemulsions formula contains the organic phase consisting of SPC (9.8 mM), Mal-PEG-DSPE (0.2 mM) and 0.5% v/v soybean oil, reconstituted in an aqueous phase containing glycerin, as surfactant. Lipid nanoemulsions were prepared by the ultrasonication method. Briefly, the protocol was carried out as follows: the organic phase, and a fixed volume of ethanol (60 µL) containing or not the flavonoid, was evaporated on a rotary evaporator (Laborota 4000, Heidolph) at 40 °C, in vacuum. The residual was resuspended in the aqueous phase, containing 1 mL of water and 10% glycerin. The coarse emulsion was sonicated for 10 min using a UPH200H probe-type sonicator from Hielscher. The nanoemulsions was further centrifuged using a 100 kDa cut-off Amicon centrifugal column to remove non-encapsulated flavonoid and traces of organic solvents. Light exposure was minimized to prevent the photodegradation of flavonoids. The lipid nanoemulsions were characterized by determining the size and zeta potential using a ZetaSizer NanoZS instrument (Malvern Instruments, Malvern, UK).
To fluorescently label the lipid nanoemulsions, 1.5% (mole/mole) Rhodamine-PE was added as an ethanol solution subsequent to LN preparation and incubated 30 min at room temperature in the dark.

A Malvern Zetasizer Nano ZS
instrument was used to analyze 6 μm PMMA latex particles before
and after chitosan adsorption and silica deposition. The Smoluchowski
approximation was applied to calculate zeta potentials using the Henry
equation. PMMA latex suspensions were diluted to 0.05% w/w using 1
mM KCl as background electrolyte. The pH of each suspension was monitored
using a pH probe and adjusted as required using either 0.5 M HCl or
0.5 M NaOH. Each measurement was performed in triplicate to obtain
a mean value.

PLGA-encapsulated CRIF1 siRNA nanoparticles were prepared by Nanoglia Inc. (Daejeon, Republic of Korea). First, 20 μM CRIF1 siRNA in 200 μL Tris–ethylenediaminetetraacetic acid buffer (pH 8.0) was added dropwise to 800 µL of dichloromethane, containing 25 mg of PLGA (Corbion, Amsterdam, Netherlands); the mixture was emulsified by sonication (50 W, 1 min; Vibra-Cell VCX 130, Sonics, Newtown, CT, USA) into a W1/O emulsion. The emulsion was diluted with 5 mL of 1% PVA1500 (w/v), then stirred with a magnetic stirring bar for 3 h at room temperature to evaporate the dichloromethane. Finally, the PLGA nanoparticles were collected by ultracentrifugation at 15,000× g for 15 min at 4 °C, then washed with deionized water, and freeze-dried for 24 h. The physical characteristics of the nanoparticles were analyzed using a Zetasizer Nano ZS instrument (Malvern Instruments, Malvern, UK) and an electron microscope. The release of CRIF1 siRNA from the nanoparticles was assessed by incubation for 0, 1, 2, or 3 days. The supernatant was harvested and diluted with PBS, and the percentage of released CRIF1 siRNA was measured using a NanoDrop (Thermo Fisher Scientific, Waltham MA, USA).

The SPION (5 mg) in 1 mL n-hexan was mixed with 13 mg F127 and 2 mg F127-Folate in 10 mL deionized water. The mixture was emulsified by vortexing for 2 min and further sonicated in water bath for 10 min. The n-hexan was allowed to evaporate overnight by magnetic stirring at 200 rpm/min. The nanoparticles were further washed with deionized water by centrifugation at 30,000 g for 30 min. This process was conducted in triplicate.
For fluorescent labeling, Nile Red (0.05 mg)—a hydrophobic fluorescent dye- was added to the n-hexane before emulsion. Nile Red absorbed to the hydrophobic layer of particles, thus making F127-Folate coated SPION/Nile Red [19 (link)].
The particle core size, morphology and diffraction (Figure A1) were also visualized by TEM instrument (TEMEDAX-20, Hillsboro, OR, USA) on a carbon coated copper grid.
The particle hydrodynamic size, polydispersity index (PDI), and zeta potential were characterized using Malvern Zetasizer Nano ZS instrument, Wocestershire, UK. The F127 coated SPION were synthesized in the same way and used as the control nanoparticles.