Abstract
The double-helical structure of double-stranded DNA enables it to form complexes with antibiotics and cytokines. The present study investigated the complex formation for antibiotic or cytokine towards DNA using quarts-crystal microbalance (QCM) technique. The resonance frequency decreases in QCM system linearly upon the increase of adsorbed mass on the QCM sensor at the nanogram level. Biotinylated DNA can easily bind avidin molecules, and DNA could be immobilized onto QCM sensor, which was sputtered with gold. The crystal resonant frequency shift was immediately measured after the injection of daunorubicin hydrochloride, which was an antibiotics, and of basic fibroblast growth factor (b-FGF), which was a growth factor. The present study can monitor the complex formation between daunorubicin hydrochloride or b-FGF and DNA using QCM method, and binding amount of daunorubicin hydrochloride or b-FGF towards DNA can be easily estimated by the frequency decrease. In addition, the difference of binding mode of daunorubicin hydrochloride and b-FGF towards DNA was revealed by the frequency shift. The QCM method is a useful for monitoring DNA complex formation with antibiotics or cytokines.
