摘要:
Modifications in the sequence of Aequorea wild-type GFP provide products having markedly different excitation and emission spectra from corresponding products from wild-type GFP. In one class of modifications, the product derived from the modified GFP exhibits an alteration in the ratio of two main excitation peaks observed with the product derived from wild-type GFP. In another class, the product derived from the modified GFP fluoresces at a shorter wavelength than the corresponding product from wild-type GFP. In yet another class of modifications, the product derived from the modified GFP exhibits only a single excitation peak and enhanced emission relative to the product derived from wild-type GFP.
摘要:
A scanning confocal microscopes scans a sample (16) with an incident beam of ultraviolet radiation, in a raster scan pattern, causing the sample to fluoresce and emit visible radiation, a portion of which retraces a portion of the path optical of incident beam, to a dichroic mirror (8) that separates it from the incident beam for detection by a photomultiplier (22,26) tube. A clock signal for clocking the output of the photomultiplier tube is provided by a reference beam system that directs a reference beam (RB) onto the same scanning mirror (9) as is the incident beam, at a coincident location on that mirror, and from there through a Ronchi grating (44) having a uniform series of alternating transparent and opaque regions. The resulting pulsed reference beam is detected by a second photomultiplier tube (46), to produce a clock signal that is an accurate representation of the instantaneous scan rate of the reference beam and, thereby, the scanning incident beam.
摘要:
Modifications in the sequence of Aequorea wild-type GFP provide products having different excitation and emission spectra from corresponding products from wild-type GFP. In one class of modifications, the product derived from the modified GFP exhibits an alteration in the ratio of two main excitation peaks observed with the product derived from wild-type GFP. In another class, the product derived from the modified GFP fluoresces at a shorter wavelength than the corresponding product from wild-type GFP. In yet another class of modifications, the product derived from the modified GFP exhibits only a single excitation peak and enhanced emission relative to the product derived from wild-type GFP.
摘要:
Protecting groups derived from a halogenated coumarin group, a quinoline-2-one group, a xanthene group, a thioxanthene group, a selenoxanthene group, or an anthracene group are described. The protecting groups is photolabile and can be removed by irradiating the group with light, such as flash photolysis with ultraviolet radiation or pulsed infrared radiation.
摘要:
A scanning confocal microscopes scans a sample (16) with an incident beam of ultraviolet radiation, in a raster scan pattern, causing the sample to fluoresce and emit visible radiation, a portion of which retraces a portion of the path optical of incident beam, to a dichroic mirror (8) that separates it from the incident beam for detection by a photomultiplier (22,26) tube. A clock signal for clocking the output of the photomultiplier tube is provided by a reference beam system that directs a reference beam (RB) onto the same scanning mirror (9) as is the incident beam, at a coincident location on that mirror, and from there through a Ronchi grating (44) having a uniform series of alternating transparent and opaque regions. The resulting pulsed reference beam is detected by a second photomultiplier tube (46), to produce a clock signal that is an accurate representation of the instantaneous scan rate of the reference beam and, thereby, the scanning incident beam.
摘要:
A scanning confocal microscope scans a sample with an incident beam of radiation, in a raster scan pattern, causing the sample to fluoresce and emit visible radiation in at least two wavelengths. A portion of the fluorescent light retraces a portion of the path optical of incident beam, to a dichroic mirror that separates it from the incident beam for detection by a pair of photomultiplier tubes. A data processor accumulates digital data from the photomultiplier tubes to form a succession of image data frames of the sample being scanned, in the two wavelengths. Image data for a selected number of frames in each wavelength is averaged and then recorded on a single track of a recording system, in an alternating fashion with averaged data for the other wavelength. In addition, a ratio of the averaged data for the two wavelengths is delivered to a video display.