Developing hydrogels for gene therapy and tissue engineering

Table 3 Loading method of therapeutic genes

Types	Loading method	Principle	Loaded gene	Advantages	Ref
Physical loading	Freeze-drying	Freezing, lyophilization	RNA	High stability	[133, 134]
	Injection	High-pressure gas injection	siRNA	Low pollution, simple process	[135, 136]
	Centrifugal coprecipitation	Mixing of the original gel solution, centrifugation, precipitation of the gel	mRNA	High precision, simple process	[137, 138]
Chemical loading	Hydrogen bond	Electrostatic interaction forces between atoms	siRNA	Mechanical properties, reversibility	[139, 140]
	Ionic bond	Electric charge interaction	mRNA, siRNA	Antimicrobial, frost resistance, and electrochemical stability	[12, 141]
	Covalent bond	Common electron pair	siRNA	Good elasticity, self-healing	[43, 142, 143]
	Hydrophobic interaction	Pro/hydrophobic attraction or repulsion	siRNA	Highly sensitive, reversible	[102, 144]

ISSN: 1477-3155