Ftir 2000

Fourier transform infrared (FTIR) spectra of the prepared samples were measured from 400 to 4000 cm⁻¹ (Model Perkin Elmer FTIR-2000, Perkin Elmer, New York, NY, USA). FESEM images were taken to study the surface morphologies of raw biomass, unactivated and activated biochar. Elemental analysis of the prepared samples in terms of carbon, hydrogen, nitrogen and others was performed by using the Elemental Analyzer (PerkinElmer-2400, Tokyo, Japan).The surface area along with micropore volume and the area of the prepared biochar were analyzed by the Autosorb-1, Quantachrome Autosorb surface analyzer (Nova, FL, USA). Before performing the nitrogen gas adsorption-desorption at 77 K, the prepared char samples were outgassed under vacuum at 300°C for 4 h to remove any moisture content from the solid surface. At a constant temperature, a relative pressure of nitrogen gas flow over the sample inside the closed vessel of the surface area analyzer will be varied, and the volume of gas adsorbed will be recorded. The volume of gas adsorbed at different pressures was plotted until the equilibrium contact time. The porous texture of the prepared samples were obtained by using the BET equation to N₂ adsorption at 77 K. The abovementioned procedure was automatically performed by software (Micropore version 2.26, Nova, FL, USA) available within the instrument.

The chemical structures of modified CS and the synthesized MPs were determined with FTIR spectroscopy. FTIR spectra were recorded with an FTIR spectrometer (model FTIR-2000, Perkin Elmer, Waltham, MA, USA) using potassium bromide (KBr) discs (thickness of 500 μm after pressure). The spectra were collected in the range from 4000 to 400 cm⁻¹ at a resolution of 4 cm⁻¹ (total of 16 co-added scans), while the baseline was corrected and converted into absorbance mode.

The infrared band assignment of each glass composition was determined by FTIR (FT-IR 2000 and Timebase software, Perkin Elmer, Seer Green, UK). Specimens of glass powder were placed on an attenuated total reflectance accessory (Golden Gate, Specac, Orpington, UK) and spectra in the range of 2000–600 cm⁻¹ were acquired at room temperature in absorbance mode.

The chemical structures of neat PLA and PLA/J were determined with FTIR spectroscopy. FTIR spectra of the samples were recorded utilizing an FTIR-2000 (Perkin Elmer, Waltham, MA, USA). A small amount of filament was hot-pressed for a few seconds in order to create thin films for testing. The spectra were collected in the range from 400 to 4000 cm⁻¹ at a resolution of 4 cm⁻¹ (total of 16 co-added scans), while the baseline was corrected and converted into absorbance mode.

Perkin-Elmer Fourier transform infrared (FTIR) spectrophotometer was used for the FTIR analysis. The KBr salts were combined with the tested extracts using a mortar, and thin pellets were created by compression. Each sample was independently placed into the FTIR spectroscope (PerkinElmer FTIR2000, Waltham, MA, USA). The average of two separate observations from 4000 to 400 cm⁻¹ with 128 scans, each at a resolution of 2 cm⁻¹, was used to create each spectrum.

In order to prove the polydopamine coating on the fibers, the appearance photographs of PLGA and pDA/PLGA fibers were taken. The microstructure images of the membranes were obtained by an environmental scanning electron microscope (ESEM, XL30 ESEM-FEG, FEI). Fiber diameter for each sample was measured and recorded using ImageJ. The average fiber diameter was a statistic based on at least 5 photos from each sample. Fourier transform infrared spectroscopy (FT-IR, Perkin Elmer, FTIR-2000) was used to determine the chemical structure of the membranes. X-ray photoelectron spectroscopy (XPS) (Thermo) was employed to detect the protein-modified substrates. The elemental compositions of the modified substrates were obtained. The water contact angle was detected on a Kriss DSA 10 instrument. The shape of the water drop was recorded by a camera and the water contact angle was measured.