Adsorption and covalent coupling of ATP-binding DNA aptamers onto cellulose

Langmuir. 2007 Jan 30;23(3):1300-2. doi: 10.1021/la060961c.

Abstract

With the long-term goal of developing paper surfaces that will detect pathogens, we have investigated physical adsorption and covalent coupling as strategies for treating cellulose surfaces with a DNA aptamer that binds ATP. Physical adsorption was reversible and the isotherms fitted the Langmuir equation with an adsorption maximum of 0.105 mg/m2 at high ionic strength (300 mM NaCl, 25 mM Tris-HCl) and only 0.024 mg/m2 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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / chemistry*
  • Adsorption
  • Aptamers, Nucleotide / chemistry*
  • Biosensing Techniques / methods
  • Buffers
  • Cellulose*
  • Osmolar Concentration

Substances

  • Aptamers, Nucleotide
  • Buffers
  • Adenosine Triphosphate
  • Cellulose