“…Significant advances have been made in conjugation chemistry in connection to: new conjugation sites (Balan et al, 2007; Giorgi, Agusti, & de Lederkremer, 2020; Katre, 2020; Picken, Awwad, Zloh, Khalili, & Brocchini, 2020), the development of enzymatic coupling methods (Grigoletto & Maso, 2020; Grigoletto, Mero, Maso, & Pasut, 2017), and a new protein expression system that makes it possible to incorporate unnatural amino acids into the protein sequence with unique reactivities towards the desired polymer (Axup et al, 2012; Nairn, Grabstein, Shanebeck, Li, & Wang, 2020).…”