Keywords: 2-Hydroxypyridine-N-oxide (PubChem CID: 69975); Aldonic acid; Cellobionic acid; Cellobionic acid (PubChem CID: 6452827); Cellulose; Fluorescence labeling; HPLC; N,N′-diisopropylcarbodiimide (PubChem CID: 12734); N-(1-naphthyl)ethylenediamine (PubChem CID: 15107); NED.