The invention discloses photoresponsive
protein hydrogel with wide-area mechanical regulation characteristics. The photoresponsive
protein hydrogel is formed by polymerizing a specific
mutant of photoactivated xanthoprotein (PYP) and a multi-arm
polyethylene glycol derivative with the
tail end modified with a
maleimide group. Through
rational design of
molecular dynamics and material
mechanics,
cysteine mutation is carried out on the 48th site and the 85th site of a
wild type PYP sequence, and the PYP (48 / 85)
double mutant with an anisotropic unfolding energy scene is constructed. According to the
mutant, exposed sulfydryl and a multi-arm
polyethylene glycol derivative are subjected to Michael
addition reaction to form a cross-linked network. Compared with the prior art (such as PYP 36 / 128 hydrogel), the method has the advantages that higher mechanical sensitivity and unfolding probability of PYP 48 / 85 under network tension are utilized, the limitation that traditional design only depends on
chain length change is overcome, and remarkably larger macroscopic rigidity adjusting amplitude (the mechanical switch ratio can reach 70% or above) is achieved. The material has the characteristics of good
biocompatibility, high response speed (
millisecond level), complete reversibility and wide rigidity
dynamic range, and can meet the biological application requirements of
stem cell differentiation,
tissue fibrosis model construction and the like with high requirements on a mechanical
signal threshold.