Study of the Interaction of Methylene Violet with Calf Thymus DNA Using an SPR-Based DNA Sensor

Abstract

Electrochemical and surface plasmon resonance technologies were combined to detect binding of low-molecular-weight compounds to DNA. First, zirconia thin films were electrochemically deposited onto bare gold electrodes. Second, calf thymus DNA was attached onto the zirconia thin films. Finally, the interaction of methylene violet with the DNA-modified surface was tested. The binding isotherm gave a K_D of 2.21 × 10⁻⁵ M. Fluorescence quenching experiments were performed to confirm the interaction. Regenerating surfaces with 1 mM NaOH provided reusable surfaces. This study provides a generic platform which can be tailored for the study of interactions of small molecules with DNA.

Keywords:

• DNA biosensor
• Interaction
• Methylene violet
• Surface plasmon resonance
• Zirconia thin films

Notes

^a Mean ± SD (n = 3).