Spectrum 100 fourier transform infrared ft ir spectrophotometer

Fourier transform infrared spectroscopy (FT-IR) analysis was carried out to evaluate potential interactions between each drug and polymer and to qualitatively evaluate the efficiency of encapsulation of both drugs using a Spectrum 100 Fourier Transform Infrared (FT-IR) spectrophotometer (Perkin Elmer, Shelton, CT, USA). FT-IR spectra were acquired for blank nanoparticles, brusatol- and docetaxel-loaded nanoparticles, pure brusatol, pure docetaxel, PLGA-PEG polymer, physical admixture of polymer and drugs, and overlaid.

^1.H and ¹³C Nuclear magnetic Resonance (NMR) spectra (collected in the Supplementary Materials) were recorded on a Bruker (Billerica, MA, US) Avance III HD 400 (¹H, 400MHz; ¹³C 100 MHz) or Bruker Ultrashield 500 (¹H, 500 Mhz; ¹³C 125 MHZ) in deuteriochloroform (CDCl₃), with either tetramethylsilane (TMS) (0.00 ppm ¹H, 0.00 ppm ¹³C), chloroform (7.26 ppm ¹H, 77.00 ppm ¹³C). Data are reported in the following order: chemical shift in ppm, multiplicities (br (broadened), s (singlet), d (doublet), t (triplet), q (quartet), m (multiplet), exch (exchangeable), app (apparent)), coupling constants, J (Hz) and integration. Infrared spectra were recorded on a Perkin Elmer (Waltham, MA, US) Spectrum 100 Fourier-transform infrared (FTIR) spectrophotometer. Peaks are reported (cm⁻¹) with the following relative intensities: s (strong, 67–100%), m (medium, 40–67%), and w (weak, 20–40%). Melting points are not corrected. TLC was conducted in Silica gel on TLC Al foils. Detection was done by UV light (254 or 365 nm). High-resolution mass spectrometry (HRMS) samples were determined on a MaXis Impact ESI-QTOF-MS (Bruker Daltonics) by electrospray ionization in positive mode (ESI+) and recorded via the time of fly (TOF) method.
The corresponding reaction conditions for each compound as well as their characterization data are detailed in the Supplementary Materials.