Mwco 12400

The resulting supernatant obtained from the isolation of proteins was subjected to dialysis (dialysis bags, MWCO 12400, 99.99%, Sigma-Aldrich, Germany) to remove all impurities (excess of salts, ions). The process of dialysis was carried out using a magnetic stirrer at 4°C for 24 hours. Polyacrylamide gel electrophoresis under denaturing conditions (SDS-PAGE) was conducted according to the Laemmli method [10 ] in 4% stacking gel and 20% separating gel (Mini-PROTEAN TGX Precast Gels, Bio-Rad). To determine the molecular weight, an appropriate molecular weight marker (Precision Plus Protein Dual Xtra Standards, Bio-Rad) was used. To visualize protein bands, the gels were stained with Coomassie Brilliant Blue R-250. Electrophoretically separated proteins were documented with GelDoc 2000 Gel Documentation System (Bio-Rad, France).

TEMPO oxidised cellulose nanofibrils (OCNF) [4 (link),5 (link)] with ~25% degree of oxidation were produced from softwood pulp via a high-pressure homogeniser [36 (link),37 (link)]. The OCNF were further purified via dialysis (using cellulose acetate dialysis tubing, MWCO 12400, Sigma-Aldrich, Gillingham, UK) under ultra-pure DI water, 18.2 MΩ cm, for five days (refreshed twice daily). After dialysis, never-dried OCNF suspensions (1 and 2 wt%) were prepared by dilution of the dialysed stock, dispersed using a sonication probe (1 s on 1 s off pulse mode for a net time of 60 min at 30% amplitude, Ultrasonic Processor, FB-505, power 500 W).
starch (Soluble, S9765) with amylose content ~34% [14 (link)] was purchased from Sigma-Aldrich, UK. starch dispersion (1 and 2 wt%) was also prepared by dissolving the required amount of starch in DI water at 80 °C for 45 min under continuous stirring. Blend gels were prepared by mixing the OCNF (2 wt%) and starch (2 wt%) suspensions (at 1:1 ratio with a total solid content of 2 wt%), followed by vortex mixing until homogeneous hydrogels were obtained. The required amount of sodium chloride (Sigma-Aldrich, UK) was added to the starch solution prior to mixing with OCNF. The pH of the gels was adjusted using HCl and NaOH solutions. Ultra-pure DI water (18.2 MΩ cm) was used for dilutions and sample preparation.