Ntegra scanning probe microscope

A NTEGRA scanning probe microscope (NT-MDT Spectrum Instruments, Moscow, Russia), in atomic force microscopy (AFM) configuration, was used to collect the 2D and 3D surface images for the polyphenol-loaded XG/PVA composite hydrogel films. The film surfaces were scanned using rectangular silicon cantilevers NSG 03 (NT-MDT, Russia) having tips of equal height and aspect ratio. The Nova v.19891 for Solver software was used to process the AFM images and calculate the surface parameters [76 (link)].

The AFM scans are done in a NTEGRA scanning probe microscope from NT-MDT with a Smena measuring head. The scans are performed in tapping mode with typical parameters of a driven frequency of 340 Hz, a magnitude of 10 nA, a set point of 5 nA and scan speed of 10–30 μm s⁻¹.

Atomic force microscopy (AFM) surface images were obtained with a NTEGRA scanning probe microscope (NT-MDT Spectrum Instruments, Moscow, Russia). Rectangular silicon cantilevers NSG11 (NT-MDT, Russia) with two different tips of high aspect ratio (sharpened pyramidal tip, angle of nearly 20°, tip curvature radius of 10 nm and height of 10–15 µm) were used in order to minimize convolution effects. Here, we used the shorter (100 ± 5 µm) of those two. For sample preparation, 5 µL of the solutions were dropped onto the freshly cleaved mica surface and allowed to dry for 24 h at RT. All images were acquired in air, at room temperature (23 °C), in tapping mode, with the velocity of 6 mm/s. For image acquisition, the Nova v.19891 for Solver software was used.
Fourier Transformed Infrared Spectroscopy in the Attenuated Total Reflection (FTIR-ATR) measurements have been recorded at 4 cm⁻¹ resolution with 140 scans recording, using an IR Tracer-100 FT-IR spectrometer (Shimadzu Corporation, Japan) equipped with a GladeATR module (PIKE Technologies, Madison, WI, USA). For each sample, the evaluations were made on the average spectrum obtained from three recordings. Background and sample spectra were obtained in the 400 to 4000 cm⁻¹ wavenumber range.