Avance dmx 500 spectrometer

¹H NMR and ¹³C NMR spectra were recorded on a Bruker Avance DMX500 spectrometer in CDCl₃ or (CD₃)₂SO with tetramethylsilane as the internal standard. The molecular weight and molecular weight distribution of these polymers were all determined by gel permeation chromatography (GPC), which was recorded on a Wyatt GPC/SEC-MALS using DMF as the mobile phase with a flow rate of 1.0 mL min⁻¹. The solution concentration was 10 mg mL⁻¹ and filtered before analysis. The FT-IR spectra were measured by a Nicolet iS 10.

All chemical reagents were commercially available and used as received. Dichloromethane was dried and redistilled with CaH₂. Other solvents were employed as purchased. NMR spectra were collected on a Bruker AVANCE DMX-500 spectrometer at room temperature. Chemical shifts (δ) are given in ppm and referenced to the standard TMS or residual solvent peaks. Mass spectra were recorded on an Agilent Technologies 6530 Q-TOF mass spectrometer with ESI resource. Dynamic light scattering (DLS) were recorded on a Malvern Nanosizer S instrument at room temperature. Transmission electron microscope (TEM) was performed at 120 kV using JEM-2010 or JEM-1010. Scanning electron microscope (SEM) was done with a JSM-6390LV or TM-1000 using second electron images. High-resolution transmission electron microscope (HRTEM) was carried out on a JEM-2100F at room temperature. Atomic force microscope (AFM) was carried out on a Bruker ICON3-sys. UV-vis spectra were measured with a Hitachi UH-5300 at room temperature. Fluorescence spectra were recorded on a Perkin Elmer LS55 at room temperature. Fourier transform infrared (FTIR) spectroscopy was carried out on a Thermo Scientific Nicolet iS50 at room temperature and only noteworthy absorptions (in cm^–1) are listed.

The purified compounds from SBM were identified by electrospray ionization-mass spectrometry (ESI-MS), ¹H NMR and ¹³C NMR spectrometry. The ESI-MS was carried out in a LCQ-Fleet mass spectrometer (Thermo Fisher Scientific, Waltham, MA), with an electrospray ionization source using a negative mode (m/z 50–800). ¹H NMR spectra and ¹³C NMR spectra were recorded on a Bruker Avance DMX-500 spectrometer (Bruker Biospin GmbH, Germany), operating at 500 and 125 MHz for ¹H and ¹³C, respectively, using D₂O or deuterated dimethyl sulfoxide (DMSO-d6). In D₂O, tetramethylsilane (TMS) was used as the internal standard. In DMSO-d₆, the residual solvent was used as the internal standard. Chemical shifts were expressed in δ (ppm) downfield from TMS as an internal standard, and coupling constants were reported in hertz.

¹H-NMR spectra were recorded on a Bruker Avance DMX 500 spectrometer using CDCl₃ as solvent and tetramethylsilane as internal reference. The molecular weight and molecular weight distribution were determined by size exclusion chromatographic (SEC). The SEC system consisted of a Waters degasser, a Waters 1525 HPLC pump with 717 plus autosampler, Waters 2410 RI detector and columns: Styragel, HT 3; HT 4. The calibration was performed with commercial polystyrene standards. Tetrahydrofuran (THF) was used as the mobile phase at a flow rate of 1.0 mL/min at 40℃.