Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12951-022-01511-9/MediaObjects/12951_2022_1511_Fig2_HTML.png)
A FT-IR spectra of nHA, Alg, and Col components as well as their mixture of Alg-nHA-Col. B Influence of crosslinking agent on the swelling ratio of Alg-nHA-Col composite hydrogel during 96 h incubation periods in PBS solution (n = 3). C The compressive strength-strain curve for various hydrogel compositions at strain 60%, C, a compressive strength-strain curve for various hydrogel compositions at strain 30%. The error bars indicate ± standard error, n = 8. D Secant modulus of elasticity of the hydrogels calculated from the Compressive strength–strain at strain 60% could be tuned from 200 to 300 kPa. The degradation rate of hydrogels in PBS-lysozyme solution during 28 days (n = 3). (**p < 0.01; ***p < 0.0001; and ****p < 0.00001)