Paper is extensively used as a barrier for protection from pathogens in applications such as medical face masks and protective clothing reflecting the fact that paper is inexpensive, disposable, autoclavable and can have well defined porosity. Nevertheless, in most protective applications, paper functions simply as a passive barrier or filter. Recognizing that the there is an opportunity to improve the functionality of paper, a network of Canadian academic researchers have embarked on a research program to develop "bioactive paper" which we define as paper which can which detect and repel or deactivate waterborne and airborne pathogens. A key requirement for bioactive paper is the presence of bio-recognition molecules coupled to a signaling mechanism on paper surfaces. Antibody fragments and enzymes are the most common bio-recognition agents, however, these molecules are usually very fragile and would deteriorate when dried out on a paper surface. By contrast, DNA aptamers are far more robust and thus hold promise as paper-supported bio-sensing agents. DNA aptamers are short oligonucleotides that can undergo structural rearrangement when in the presence of a specific target, resulting in the capture of the target. DNA aptamers have demonstrated the same high specificities as antibodies with pM range affinities. Furthermore, aptamers for a rapidly growing number of targets, including proteins, metals and small molecules have been obtained by in vitro selection, or SELEX (systematic evolution of ligands by exponential enrichment). We report on our initial attempts to deposit DNA aptamers onto cellulose surfaces in high yields while maintaining recognition activity. We investigated physical adsorption and covalent coupling as strategies for treating cellulose surfaces with a DNA aptamer which binds ATP. Physical adsorption was reversible and the isotherms fitted the Langmuir equation with adsorption maximum of 0.105 mg/m2 at high ionic strength (300 mM NaCl, 25 mM Tris-HCl) and only 0.024 mg/m 2 in lower ionic strength buffer (25 mM Tris-HCl). Covalent coupling of amine terminated aptamer with oxidized cellulose film (Schiff base + reduction) gave 25% coupling efficiency while maintaining the aptamer activity which was illustrated by using a known fluorescent aptamer that is capable of ATP detection. Therefore covalent coupling, without spacer molecules, is a promising approach for supporting biosensing aptamers on cellulose.