Details

Autor(en) / Beteiligte

• Földes-Papp, Zeno
• Liao, Shih-Chu Jeff
• You, Tiefeng
• Barbieri, Beniamino

Titel

Reducing background contributions in fluorescence fluctuation time-traces for single-molecule measurements in solution

Ist Teil von

• Current pharmaceutical biotechnology, 2009-08, Vol.10 (5), p.532-542

Ort / Verlag

Netherlands

Erscheinungsjahr

2009

Quelle

MEDLINE

Beschreibungen/Notizen

• We first report on the development of new microscope means that reduce background contributions in fluorescence fluctuation methods: i) excitation shutter, ii) electronic switches, and iii) early and late time-gating. The elements allow for measuring molecules at low analyte concentrations. We first found conditions of early and late time-gating with time-correlated single-photon counting that made the fluorescence signal as bright as possible compared with the fluctuations in the background count rate in a diffraction-limited optical set-up. We measured about a 140-fold increase in the amplitude of autocorrelated fluorescence fluctuations at the lowest analyte concentration of about 15 pM, which gave a signal-to-background advantage of more than two-orders of magnitude. The results of this original article pave the way for single-molecule detection in solution and in live cells without immobilization or hydrodynamic/electrokinetic focusing at longer observation times than are currently available.