Jem 1400 tem

Vestibular nuclei mitochondria were fixed in 2.5% (v/v) glutaraldehyde (Merck) in 0.1 M phosphate buffer (PB), pH 7.4 at 4°C overnight. Postfixed for 2 h with 1% (w/v) osmium tetroxide (TAAB Lab) containing 0.8% (w/v) potassium hexacyanoferrate (Sigma-Aldrich) in PB, dehydrated in gradual ethanol (50–100%), embedded in Eponate 12 resin (Ted Pella Inc.), and polymerized at 60°C for 48 h. Ultrathin sections of 50 nm were collected onto carbon-coated copper grids of 200 mesh and contrasted with conventional uranyl acetate and lead citrate solutions. Sections were visualized in a TEM Jeol JEM-1400 (Jeol Ltd., Tokyo, Japan) operating at 80 kV and equipped with a CCD Gatan ES1000W Erlang Shen camera (Gatan Inc.).

Purified IBs were checked by field emission scanning microscopy (FESEM) and transmission electron microscopy (TEM). In the first technique, sample microdrops were deposited 2 min on silicon wafers (Ted Pella Inc., Redding, CA, USA) and then air-dried. Nanoparticle micrographs were acquired at a nearly native state with a high-resolution in-lens secondary electron detector in a FESEM Zeiss Merlin (Zeiss, Oberkochen, Germany) operating at 2 kV. For TEM, nanoparticles samples were fixed with aldehydes and osmium, dehydrated, and embedded in Epon resin. Ultrathin sections were deposited on copper grids, and after contrast, observed with the electron microscope TEM Jeol JEM-1400 (Jeol Ltd., Tokyo, Japan).

The size and zeta potential of HRZ/siTGF-β1 nanoliposomes were assessed by dynamic light scattering (DLS) on a Malvern ZetasizerNano ZS (Malvern Instruments, UK) in triplicate at ambient, after dilution with double-distilled water.
The surface morphology of HRZ/siTGF-β1 nanoliposomes was assessed by transmission electron microscope (TEM) (TEM Jeol JEM-1400; JEOL, Japan). A 5:1 mass ratio of cationic nanoliposomes and siRNA was spread over a copper grid and air-dried for 30 min before detection to prepare TEM samples.
As reported previously, INH, RIF, and PZA loading in HRZ/siTGF-β1 nanoliposomes were assessed with slight modifications [34 (link)]. Briefly, the mobile phase was formulated to an optimal concentration to detect the EE of HRZ/siTGF-β1 nanoliposomes on a high-performance liquid chromatography (HPLC) system (Agilent Technologies, USA). After the loading procedure, the suspensions were submitted to centrifugation at 16,873 g for 20 min (Centrifuge 5418; Eppendorf AG, Germany). Unencapsulated drugs that remained in the supernatant were quantitated by UV detection at 334.00 nm [35 (link)].
Entrapment efficiency (%) was derived as [(weight of drug-loaded initially − the weight of unencapsulated drug)/weight of drug-loaded initially] × 100%

For negative staining, aggregated peptide samples were sonicated at intensity two for 5 min in an ultrasonic bath (VWR ultrasonic cleaner, Leuven, Belgium), placed onto carbon-coated copper grids, and incubated for 1 min. The excess of the sample was removed using ashless filter paper. Then, the grids were washed with distilled water and incubated for 1 min with 2% (w/v) uranyl acetate and the excess of uranyl acetate was removed carefully using ashless filter paper. The micrographs of aggregated peptides were obtained using a TEM JEM-1400 (JEOL, Tokio, Japan) operating at an accelerating voltage of 120 kV. Representative images of each sample were selected.