Charge-coupled device attachment

Using the same PAbs an optical biosensor system has been developed for 2,4,6-TCP [224]. The principle is the detection of laser-induced fluorescence (LIF) in single microdroplets by a homogeneous quenching fluorescence immunoassay (QFIA). The competitive immunoassay occurs in microdroplets (d=58.4 mm) produced by a piezoelectric generator system. A continuous Ar ion laser (488 nm) excites the fluorescent tracer and its fluorescence is detected by a spectrometer attached to a cooled, charge-coupled device (CCD) camera... 

Sapsford etal. (2001) examined microarray-based antibody-antigen binding kinetics in real time to determine the effect of spot size. Capture antibodies were immobilized in an array pattern onto silver-clad microscope slides. Antimouse IgG was directly attached to the surface or attached via neutravidin capture of the biotinylated antibody. Cy5-labeled mouse IgG capture was monitored based upon the signal generated from the excitation of an evanescent wave guide (slide) with a 635-nm laser source detection was achieved by a charge-coupled device (CCD) camera system. Both static and flow-through conditions were employed. 

Figure 8. Sample illumination and light collection geometry to record vibrationally resolved fluorescence spectra of a single molecule. The sample is attached to the optical flber. S sample, P paraboloidal collection mirror, M flat mirror, BS beam splitter, F long pass filter, L lens, PMT photomultiplier tube, CCD charge-coupled device detector (after Ref 38).

The most successful applications of CE-LIF detection have been in the analysis of carbohydrates and nucleic acids. Carbohydrates can be derivatized with agents such as aminopyrene trisulfonic acid, which introduces a fiuorophore and also confers electrophoretic mobility to the analyte. Double-stranded nucleic acids can be detected using intercalating dyes and by covalent attachment of nucleotides carrying fluorophores. The fluorescently labeled primers or chain terminating nucleotides which are widely used in automated slab gel-based DNA sequencers are also used in capillary-based sequencers. In one multicapillary sequencer, a novel sheath flow system is used for LIF excitation of separated bands with imaging of emitted fluorescence on a charge-coupled device (CCD) detector. 

As a switching device capable for ultra-large-scale integrated circuits (ULSIs) comprises only one Coulomb island with two leads (electrodes) and a capacitively coupled gate electrode attached to it. This system works as a simple on/off switch and it is often called the SE transistor. Applying a voltage to the outer electrodes of this circuit may either cause sequential transfer of electrons onto and out of the central island or to have no charge transport, i.e. the transistor remains in non-conductive state. The result... 

---