Thermo nicolet avatar 330

The nanofibers were gold-coated, as described by Heunis et al. [13 (link)] and the surface structure of the nanofibers studied using a scanning electron microscope (SEM, Leo 1430VP, Zeiss, Cambridge, England). From these images, the diameter of the nanofibers was calculated using ImageJ Software, version 1.46, Scion Corporation [14 (link)]. Protrusions from the nanofibers were visualised by transmission electron microscopy (TEM), using a Philips Tecnai TF20 (FEI, OR, USA). Surface topology was studied using a Nanosurf atomic force microscope (AFM) Easyscan 2 (Nanosurf Inc., CA, USA). Interactive properties of CIP, PDLLA and PEO were studied using a Fourier transform infrared (FTIR) spectroscope (Thermo Nicolet Avatar 330, Thermo Scientific, Waltham, MA, USA), equipped with a Smart Performer Zn/Se ATR (attenuated total reflection) accessory. Crystal formation and phase compositions were observed by X-ray diffraction (XRD), using a Bruker AXS D8 Advance X-ray diffractometer (Bruker AXS, Frankfurt, Germany) operated in locked coupled mode. The instrument was equipped with a Vantec-1 position sensitive detector optimized for Cu-Kα radiation at λ = 1.5406 Å. The X-ray tube was operated at 40 mA and 40 kV. Readings were recorded at a scanning rate of 1 sec/step, with a step size of 0.0275° in a 2θ range that extended from 4° to 69.99°.

The interactions between the compounds of the liposome were investigated by mid-infrared (MIR) spectroscopy using a Thermo Nicolet Avatar 330 FT-IR spectrometer (Thermo Fisher Scientific, Inc., Waltham, MA, USA). Spectra were recorded on the freeze-dried powder samples in the 4000–400 cm⁻¹ wavenumber range with 4 cm⁻¹ spectral resolution in absorbance mode. Samples were prepared using a hydraulic tablet press by compressing the lyophilised powders into pellets with potassium bromide (KBr) powder at 10 kN for 2 min (Specac Ltd., Orpington, UK). Pure KBr pellets were used as references.