Nanoscope iiia software

Polyelectrolyte multilayer films were created by dip-coating of oppositely charged polyelectrolytes with a deposition robot (Riegler & Kirstein, Potsdam, Germany) according to Mohamad et al. (2019) (link). Here, we used PEI [branched, Mw = 750 kDa, polydispersity (PDI) = 12.5], polyallylamine hydrochloride (PAH, Mw = 50–60 kDa) and poly(diallyldimethylammonium chloride) (PDADMA, Mw = 322 kDa, PDI = 2.19) as polycations and poly(styrene sulfonate) sodium salt (PSS, Mw = 666 kDa, PDI < 1.2) as polyanion.
PSS-terminated PEM consisted of three double layers with the sequence PEI/PSS/(PAH/PSS)₂. PDADMA-terminated polyelectrolyte brushes were composed of 10.5 double layers with the sequence PEI/PSS/(PDADMA/PSS)₉/PDADMA. The layer stability of prepared PEM was verified by AFM measurements [DI Multimode AFM using NanoScope IIIa software from Veeco (Santa Barbara, CA, United States)]. Layers are stable in the range of pH 3–11, in solutions up to 1 M NaCl and after storage in ambient air up to 1 year unchanged.

Atomic force micrographs (AFM) were acquired using a Digital Instruments Dimension™ 3000 SPM with a NanoScope IIIa controller (Veeco instruments, Santa Barbara, California, USA) and a NanoScope IIIa software (version 4.42r4). Tapping mode was employed across the surface of the samples at a frequency of 1 Hz.
The infrared (IR) spectra were recorded in the mid-infrared region (4000–550 cm⁻¹) on a Bruker ALPHA in diamond attenuated total reflection (ATR) using Opus software. The resolution was 2 cm⁻¹ at 128 scans.
Raman spectroscopy was performed on an iHR 320 model fully automated spectrometer with a wavelength position resolution of 0.2 cm⁻¹. The excitation source was an argon ion laser (514 nm) within the wavenumber range of 0–4000 cm⁻¹.