Sodium carbonate na2co3

Elastollan® thermoplastic polyurethane pellets with 95A shore hardness (TPU 95A) was generously supplied by DistruPol Ltd, Dublin, Ireland. Fluorescein isothiocyanate–dextran (FITC-dextran 10, MW = 8000–12,000 Da) was purchased from TdB Consultancy AB (Uppsala, Sweden). Fluorescein sodium (MW = 376 Da) and poly(ethylene glycol) (PEG) with MW = 10 000 Da were purchased from Sigma-Aldrich, Dorset, UK. Gantrez® S-97, a co-polymer of methyl vinyl ether and maleic acid (PMVE/MA) was a gift from Ashland, Kidderminster, UK. Sodium carbonate (Na₂CO₃) was purchased from BDH Laboratory Supplies, London, UK. Pearlitol® 50C-Mannitol was supplied by Roquette, Lestrem, France. Cryogel SG3 was provided by PB Gelatins, Pontypridd, UK.

Gantrez® S-97, which is poly (methylvinylether/maleic acid) (PMVE/MA) with molecular mass of 1,500,000 Da was a gift from Ashland, Kidderminster, UK.Poly (ethylene glycol) (PEG), molecular weight 10,000 Da, was purchased from Sigma-Aldrich, Steinheim, Germany. Sodium carbonate (Na₂CO₃₎ was purchased from BDH Laboratory Supplies, London, UK. HPLC grade methanol, acetonitrile and triethylamine were purchased from Sigma Aldrich, Dorset, UK. Metformin HCl was purchased from Tokyo Chemical Industry Co., LTD, Tokyo, Japan. Cryogel SG3 gelatin was purchased from PB Gelatins, Pontypridd, UK. Pearlitol® 50C-Mannitol was purchased from Roquette, Lestrem, France. Depilatory cream (Boots Expert®) was purchased from The Boots Company PLC, Nottingham, UK. Parafilm® M was purchased from Bemis, Neenah, USA. All other chemicals used were of analytical reagent grade.