Ultrasensitive detection of single molecules in flowing sample streams by laser-induced fluorescence

Conference · Thu Dec 31 04:00:00 EST 1992

OSTI ID:10117383

Goodwin, P M; Wilkerson, Jr, C W; Ambrose, W P; Keller, R A

We report here on the detection and fluorescence lifetime measurement of single Rhodamine-110 molecules in a flowing, aqueous sample stream. Time-Correlated Photon Counting (TCPC) used in combination with pulsed excitation allows for the detection, in the presence of significant prompt Raman and Rayleigh background, of photon bursts due to single fluorescent molecules passing through a small detection volume ({approximately} 1 pL). The fluorescence lifetime of a detected molecule is estimated from the decay curve compiled from photon arrival times in the burst. An improved SMD apparatus which allows the detection and fluorescent lifetime measurement of individual Rhodamine-110 molecules dissolved in an aqueous sample stream. These measurements are made at a flow rate doser to those that are envisioned for rapid DNA sequencing. We present burst size distributions derived from burst data collected at Rhodamine-110 concentrations of 100 fM and 1 pM and discuss the mechanisms that lead to the observed distributions. We also present Monte Carlo generated synthetic data that supports our interpretation of the experimental results.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 10117383
• Report Number(s): LA-UR--92-4408; CONF-930159--1; ON: DE93005457
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102
550200
59 BASIC BIOLOGICAL SCIENCES
BIOCHEMISTRY
CHEMICAL AND SPECTRAL PROCEDURES
DERIVATIZATION
DESIGN
DETECTION
DNA SEQUENCING
FLUORESCENCE SPECTROSCOPY
FLUORIMETERS
LASER SPECTROSCOPY
LIFETIME
OPTIMIZATION
RHODAMINES
SENSITIVITY