The fluorescence systems offered by C&L Instruments support a wide range of applications.  Our fluorometer systems connect to fluorescence microscopes, a cuvette assembly and a bifurcated optical probe (for surface fluorescence measurements).  The modular construction of our instruments, together with the ability to measure fluorescence from up to eight excitation-emission wavelength pairs, makes this a remarkably versatile system.   The following data illustrate this versatility, as well as the sensitivity of our instruments.  Click on the images for larger versions.

Fluorescence Imaging
Our fluorometer systems can now be used for fluorescence imaging and ratio fluorescence imaging!  We support a variety of analog and digital cameras.  You can use our Model S48D Illumination Source together with a camera and our FluorImage software to image the fluorescence emission from single cells.  You can also use your existing microscope epi-illumination light source for imaging.  For further information about single cell fluorescence imaging, please visit our imaging page.

Ion Analysis (Ca²⁺, Mg²⁺, Na⁺, pH, DY, etc.)
There are numerous applications in which fluorescence can be used to measure ion concentrations or other biological parameters, such as pH and membrane potential (DY), using fluorescence indicators.  The fluorescence from these type of probes can be monitored singly or, in some cases, together in dual-probe combinations in single cells and in solution. The following examples illustrate how different configurations of the Dye Fluorometer have been used in the research laboratory. 

Calcium transients in isolated myocytes

In these experiments, the Dye Fluorometer was used to measure calcium transients in cardiac myocytes isolated from the ferret.  The effect of electrical depolarization and caffeine are shown in this figures.  Data were collected at the rate of 100 samples per second.  Myocytes were loaded with the calcium indicator fluo-3. 

Tissue Surface Fluorescence
The C&L Dye Fluorometer can connect to a bifurcated silica fiber optic probe for sensitive fluorescence measurements using the technique know as surface fluorescence. 

340/380 Fluorescence ratio from the surface of the fura-2-loaded rat heart.  Data was acquired in synchrony with the paced heart and to obtain true fluorescence ratios using the "interlace" procedure.  For details of this procedure, see Am. J. Physiol. 267:H636, 1994.  Data courtesy of Dr. Russell Scaduto, Penn State University.

Calcium in the isolated perfused heart.  In this application, alternating 340 and 380 nm light from the Model S48D Illumination Source is used to illuminate the specimen using one "leg" of a bifurcated fiber optic probe.  The common end of the probe serves to illuminate the specimen (the left ventricle of the heart in this case) and collect the fluorescence emission from the heart.  Emission light is collected and travels to the Model D48 Detector using the other leg of the bifurcated probe.  The absence of any dichroic mirrors in this arrangement allows the experimenter to use any wavelengths for excitation and emission.

Estimation of cardiac oxygen tension by surface fluorescence using the inner filter effect.

Dual probe fluorescence from the perfused rat heart.  The perfused rat heart was loaded with coumarin carboxylic acid and rhodamine to estimate the oxygenation state of mitochondrial cytochrome aa3 and myoglobin using the inner filter effect.  The excitation-emission wavelengths for each measurement are shown.  The 605/630 emission ratio is proportional to aa3 oxidation and the 415/430 excitation ratio is proportional to myoglobin oxidation.  See Am. J. Physiol. 267:H645, 1994 for details.   Data  courtesy of Dr. Russell Scaduto, Penn State University.

In this application, hearts were loaded with two fluorescent dyes that either absorb (coumarin carboxylic acid) or emit (rhodamine) light at the same wavelengths as endogenous oxygen-binding proteins in heart.  Myoglobin absorbs light at the excitation wavelength of coumarin carboxylic acid, while cytochrome aa₃ absorbs light at the emission wavelength of rhodamine.  Changes in the oxygenation state of these proteins cause their wavelengths of maximum absorbance to change, which can be observed as a change in the fluorescence properties of these probes due to the inner filter effect.