The ultraviolet–visible (UV–Vis) spectra and Fourier transform infrared (FTIR) spectra of LPs and MLPs were measured by the methods of Han et al. [4 (link)]; periodate oxidation analyses were performed with the method described by Hu et al. [15 (link)]; and atomic force microscope (AFM) images were observed according to our previous method [17 (link)].
The Mw distributions of LPs and MLPs were detected using a HPSEC system mainly composed of a model 510 pump (Waters, Milford, MA, USA), a PL aquagel-OH 40 column (8 μm, 7.5 × 300 mm, Agilent), a multi-angle laser light scattering (MALLS) detector (DAWN HELEOS-II 18, Wyatt Technology Co., Santa Barbara, CA, USA), and a differential refractive index (RI) detector (Optilab rEX, Wyatt Technology Co., Santa Barbara, CA, USA). Ammonium acetate solution (0.2 mol/L) was used as the mobile phase at a flow rate of 0.7 mL/min. Five milligrams of samples were dissolved in 2 mL ammonium acetate solution, followed by filtration through a 0.22 μm filter for injection. The injection volume was 20 μL and the column temperature was 30 °C.
After having been kept in a vacuum drier for a week, samples (30–40 mg) were put into a 5 mm NMR tube and dissolved in 1.0 mL dimethyl sulfoxide (DMSO). A Bruker AM 400 MHz spectrometer (Bruker, Rheinstetten, Germany) was used to record 1H NMR spectrum with the operating frequency of 400.13 MHz at 30 °C.
The Mw distributions of LPs and MLPs were detected using a HPSEC system mainly composed of a model 510 pump (Waters, Milford, MA, USA), a PL aquagel-OH 40 column (8 μm, 7.5 × 300 mm, Agilent), a multi-angle laser light scattering (MALLS) detector (DAWN HELEOS-II 18, Wyatt Technology Co., Santa Barbara, CA, USA), and a differential refractive index (RI) detector (Optilab rEX, Wyatt Technology Co., Santa Barbara, CA, USA). Ammonium acetate solution (0.2 mol/L) was used as the mobile phase at a flow rate of 0.7 mL/min. Five milligrams of samples were dissolved in 2 mL ammonium acetate solution, followed by filtration through a 0.22 μm filter for injection. The injection volume was 20 μL and the column temperature was 30 °C.
After having been kept in a vacuum drier for a week, samples (30–40 mg) were put into a 5 mm NMR tube and dissolved in 1.0 mL dimethyl sulfoxide (DMSO). A Bruker AM 400 MHz spectrometer (Bruker, Rheinstetten, Germany) was used to record 1H NMR spectrum with the operating frequency of 400.13 MHz at 30 °C.
Free full text: Click here
