It has been brought to our attention very recently that we had an omission error in our methods section of the paper [1]. This is Section 3.4, which should have read as follows:
The tensile strength, Young’s moduli and elongation at break of the 10% hydrogels were determined on an Instron electromechanical universal tester (Model 3342) equipped with Series IX/S software, using a crosshead speed of 10 mm·min−1 and a gauge length for testing of 5 mm. Hydrogels with 0.55 mm thickness were equilibrated in PBS and cut into 10 mm × 5 mm rectangular sheets. The load cell used was 10 N.
For 18% hydrogels, measurements were made on an Instron universal test machine (Biopuls 3343, High Wycombe, UK). The measurements were carried out under water immersion at 37 °C. Dumb-bell shaped hydrogels of 0.5 mm thickness were made for the mechanical properties measurement. The grip area at each end was 6 mm × 10 mm with a gauge segment of 14 mm × 6 mm. The mechanical testing was carried out with the crosshead moving at a speed of 10 mm·min−1 and the load cell was 50 N.
A minimum of three specimens was measured for each hydrogel formulation and repeated for three independent experiments.
Reference
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