5 channel degasser dgu 20a

GPC analysis was performed in the different stages of the degradation process with Mw 14,000 PCL. Supernatant (3 mL) was frozen in 30 mL glass vial at −15 °C and kept in lyophilic dryer at −60 °C with 80 mTor vacuum for 12 h. The sample was dissolved in 1 mL HPLC grade tetrahydrofuran (THF) for 2 h at 45 °C. The sample was filtered through 0.45 μm PTFE syringe filter in standard 2 mL chromatography vials. A GPC analyzer (Model SHIMADZU Nexera) (Shimadzu, Kyoto, Japan) equipped with 5-Channel Degasser DGU-20A, HPLC Pump LC-20AD, Autosampler SIL-20AC, Column Oven CTO-20AC, and Refractive Index Detector RID-20A was operated at 45 °C and a THF elution rate of 1.0 mL/min. The GPC Column Set PSS SDV 50 Å (300 mm × 8.00 mm × 5 μm), PSS SDV 100 Å (300 mm × 8.00 mm × 5 μm), PSS SDV Linear M (300 mm × 8.00 mm × 5 μm) were used. Shimadzu, Kyoto, Japan)

One mL of PE or UC (2900 EU for each) was incubated with one PCL pearl for each sample with a gravimetric weight 18 mg ± 3% (MW 80,000) for a week at 55 °C. A pearl in buffer was used as a control. Each sample was triple-repeated. After a week the samples were frozen in a 30 mL glass vial at −15 °C and kept in a lyophilic dryer at 60 °C with a 80 mTor vacuum for 12 h and dissolved in 1 mL HPLC grade tetrahydrofuran (THF) for 2 h at 45 °C. The samples were filtered through a 0.45 μm PTFE syringe filter in standard salinized 2 mL chromatography vials. A GPC analyzer (Model SHIMADZU Nexera) equipped with 5-Channel Degasser DGU-20A, HPLC Pump LC-20AD, Autosampler SIL-20AC, Column Oven CTO-20AC, and Refractive Index Detector RID-20A was operated at 45 °C and a THF elution rate of 1.0 mL/min. The used GPC Column Set was PSS SDV 50 Å (300 mm × 8.00 mm × 5 μm), PSS SDV 100 Å (300 mm × 8.00 mm × 5 μm), and PSS SDV Linear M (300 mm × 8.00 mm × 5 μm). Instrument Control, Data Acquisition and Data Processing were performed by GPC software Lab Solutions v.5.71 SP1.