Atr ftir

Fourier transform infrared spectroscopy (ATR-FTIR, Thermo Scientific, Winsford, UK) analysis was performed using a Nicolet iN10 FTIR microscope with a germanium microtip. The analysis was performed in the wavenumber range of 650–4000 at a resolution of 4 cm⁻¹ with 64 scans. Three spectral measurements were performed on each sample in various locations to analyze the functional groups on the surface of the composites.

In order to explore the differences between the unmodified and modified PHBV fibrous scaffolds, the toluidine blue O (TBO) staining method was used to measure the surface carboxyl density of samples according to the previously established method [32 (link)], and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) (Thermo, American) was used to investigate the surface chemical structure of tested scaffolds. Moreover, the morphology of PHBV fibrous scaffolds and PHBV-g-QUE fibrous scaffolds was observed by scanning electron microscope (SEM) (FEI Quanta 200, FEI Company, USA), and the diameter of scaffolds was calculated by the Image J software.

A PCR amplifier was bought from Thermo Fisher (Waltham, MA, USA). Electrophoresis was implemented by a Bio-Rad apparatus (Hercules, CA, USA). An automatic microplate reader (SPARK) was bought from TECAN (Männedorf, Switzerland). An Odyssey^® Imaging system was from LI-COR (Lincoln, NE, USA). A molecular interaction analyzer (ForteBio Octet K2) was bought from SARTORIUS (Gottingen, Germany). ATR–FTIR was bought from Thermo (Waltham, MA, USA).

Dynamic light scattering (DLS) and zeta-potential of the pSiNPs samples (pSiNPs-OH, pSiNPs-F, pSiNPs-F-mPEG, pSiNPs-F-NHS, and pSiNPs-F-MAL) were measured by Malvern Instruments Zetasizer Nano ZS90 (Worcester-shire, UK). The morphologies of nanoparticles were characterized by transmission electron microscopy (Tecnai, G2 F30ST, FEI Company, Hillsboro, OR, USA). Attenuated total reflectance Fourier transform infrared (ATR-FTIR, Thermo Fisher Scientific, Waltham, MA, USA) was used to observe the surface functional group of each nanoparticle.

The morphology and structure of CeMA, CMA, and CCMA composite hydrogel bead samples were identified through scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). The samples were analyzed through SEM and EDX to identify the changes in the morphology and the elemental analysis of the composite hydrogel beads. All samples were dried out beforehand using a cold vacuum to remove the moisture trapped in the hydrogel beads while retaining their shape. Samples were coated with a thin layer of gold before morphology images were taken using an acceleration voltage of 10 kV. ATR-FTIR (Thermo Scientific, Model: Nicolet iS10, Waltham, MA, USA) was used to determine the functional groups and chemical bonds that exist in CeMA, CMA, CCMA, alginate, cellulose powder, and chitosan powder. A frequency range of spectrophotometer between 4000 and 400 cm⁻¹ was applied. The thermal stability of CeMA, CMA, CCMA, alginate, cellulose powder, and chitosan powder was determined using TGA (Mettler Toledo, Zurich, Switzerland). All samples were dried at 50 °C in a drying oven overnight beforehand. Zero-weight calibration was also conducted before analysis. Approximately 10–15 mg of the samples was placed on the pan and heated with nitrogen gas purge from 30 to 700 °C at a heating rate of 10 °C per minute.

Fourier transformed infrared spectroscopy by attenuated total reflectance (ATR-FTIR, Thermo Fisher Scientific, Waltham, MA, USA) was obtained using a Spectrometer Nicolet 6700, equipped with a source IR-Turbo fitted with a detector based on deuterated triglycine sulfate (DTGS) in a beamsplitter of KBr. Background scans were 34 with a spectral resolution of 4 cm⁻¹ at ambient temperature, using an Attenuated Total Reflectance (ATR) accessory. Gelatin was deposited in a gold support in a humid chamber to avoid evaporation during measurements. A study of the second derivative of the spectra of Amide I was carried out, using the first difference derivative (FDD) method.