Table 1.

Comparison of different usages of click chemistry in virus-related research.

Usage	Advantages	Disadvantages	Reference
Viral tracking	•Small monomeric tag •Can label viral nucleic acid, protein or both •Highly selective •Rapid and quantitative labeling •Specifically reacts with its substrates •Highly stable •Metal free click reaction is nontoxic	•Potential copper toxicity in the Cu(I)-catalyzed click reaction •Tracking of partial infection cycles •Requires membrane-permeable substrate •Sometimes a high amount of background	Liu et al. (2017)
Antiviral agent	•High flexibility and selectivity •Stable products •Easily synthesized	•Susceptibility to protease degradation •Poor bioavailability	Ahmad Fuaad et al. (2013), McGowan et al. (2017), Tian et al. (2017), Xiao et al. (2014), (2016)
Diagnosis of viral infection	•Highly efficient, high sensitivity and good selectivity. •Enzyme-free and amplification-free nucleic acid assays •Simple equipment and easy operation.	•Susceptibility to protease or DNase degradation •Nonspecific binding needs to be considered •Clinical samples, such as whole blood or serum, may affect the detection result	Qi et al. (2017), Thomson and Cooper (2013), Thomson et al. (2012); Yue et al. (2014)
Virus-based delivery system	•Low temperature •Controllable synthetic processes	•Copper is cytotoxic in vivo •Metabolic pathways of triazoles are not clear	Li et al. (2013), Picard-Lafond and Morin (2017)