ABSTRACT: A method for characterization and optimization of DNA sequencing systems based on capillary electrophoresis is proposed. A
model is developed that relates the read length of a sequencing run and the parameters of DNA sequencing systems such as the
properties of the separation medium, capillary length, injection time, concentration of the injected DNA sample, detection
sensitivity, system noise, and the illumination power. The optimization of DNA sequencing systems will allow determination
of optimum regimes for preparation, injection, and separation of DNA samples needed for achieving a read length required.
The method proposed is applied to the characterization of capillary-electrophoretic DNA sequencing systems based on single-photon
Technical Physics 04/2012; 53(6):763-775. · 0.50 Impact Factor
ABSTRACT: This paper describes design of the new ultra sensitive sensor system for fluorescence detection applications. System comprises two units: optical spectra separation unit and detection unit. Optical unit of the sensor performs spatial spectra separation of signal from the laser excited fluorescence, and resulting spectra is collected in the detection part of the system. Optical part is built using diffraction grating as spectra separation element. Detection part comprises 32-channel photomultiplier tube working in single photon counting mode with our 32-channel amplifier. Using single photon detection technique and specific signal processing algorithms for collected data, the proposed system allows to achieve unique combination of characteristics--high sensitivity, high detection speed and wide linearity dynamic range comparing to existing commercial instruments. DNA sequencing experiments with new sensor as detection device, and using two types of lasers (Ar-ion and Nd-YAG) were carried out, yielding sequencing traces which have quality factor of 20 for read lengths as long as 650 base pairs.
Biosensors and Bioelectronics 06/2008; 23(10):1512-8. · 5.60 Impact Factor
ABSTRACT: We present the design, implementation, and characterization of a single-photon counting module (SPCM) based on large-area avalanche photodiode (APD) and new logic circuit based on TTL integrated circuits (ICs) for generating precise quench and reset delays. Low dark count rate, high linearity of 2 MHz, maximum dynamic range of 12 MHz, and minimum dead time of 35 ns have been achieved with 0.2 mm peltier-cooled single photon avalanche diode (SPAD) [model C30902S-DTC, Perkin Elmer Optoelectronics (PKI)]. The developed module was fiberized and tested for the detection of fluorescently labeled DNA sequences. Detection sensitivity at the level of single fluorescent molecule has been demonstrated.
IEEE Journal of Selected Topics in Quantum Electronics 08/2007; · 3.78 Impact Factor