Table 2.

Main functions through the covalent pathway of grapheme oxide and its applications

Covalent functioning method
Mechanism	Reagents	Application	References
Amination	DNA	Biosensor	Li et al. [135]
	Chitosan		Begum et al. [132]
	BSA		Ye et al. [134]
	PANI		Yang et al. [317]
	Octa-arginine	Carrier	Imani et al. [138]
	PEGA		Abdollahi et al. [139]
	HPAA		Liu et al. [140]
	mPEG – NH2		Yang et al. [141]
	TETA	Water of remediation	Sun et al. [318]
	PEI		Wang et al. [143]
	DABu and DABe	Catalysis	Ahmed and Kim [319]
	TPAPAM	Electronic device	Fan et al. [320]
Esterification	FcAED	Biosensor	Xiao et al. [144]
	Borneol	Carrier	Li et al. [145]
	β-Cyclodextrin		Meng et al. [146]
	TAA	Tissue engineering	Sarvari et al. [147]
	Starch		Wu et al. [148]
	Polyglycerol	Water of remediation	Yu et al. [321]
	TBPP		Yao et al. [322]
	PPy–COOH and PPy–COOCl	Catalysis	Luceño-Sánchez and Díez-Pascual [323]
	Benzyl alcohol	Electronic device	Tachi et al. [324]
	Glycerol		Raheem et al. [149]
	PVA		Li et al. [325]
Silanization	AEAPTMS	Theranostics	Wen et al. [151]
	CPTS	Water of remediation	Hassan et al. [152]
	β-CD/GPTMS		Yu et al. [155]
	GPTMS-MTES	Electronic device	Lee et al. [326]