Regular instrument calibration and adjustment are required for high-precision imaging of fluorescent probes, particularly in multicolor applications such as confocal laser scanning microscopy that involve multiple exposures, repetitive scans, or three-dimensional sectioning.

We offer a range Molecular Probes calibration products to help you achieve optimum performance from your imaging system:

Imaging dye standards

Fluorescence intensities are influenced by a variety of sampler- and instrument-related parameters. Consequently, comparisons between data acquired on different instruments or with long intervals (several days or more) between measurements must be made with reference to standard fluorescent materials.  

The Molecular Probes Reference Dye Sampler Kit provides samples of five extensively characterized fluorescence standards with emission spectra covering the entire visible wavelength range.

In addition, we offer a Molecular Probes NIST-traceable standard solution directly traceable to SRM 1932. This fluorescein standard can be used as a reference material for calibrating instruments or for determining molecules of equivalent soluble fluorophore (MESF) values for experimental solutions.

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Bovine pulmonary artery endothelial cells (BPAEC). FluoCells prepared slide #2.

FocalCheck Calibration Beads

Our Molecular Probes FocalCheck fluorescent microspheres are specifically designed for examining the alignment, sensitivity, and stability of confocal laser scanning microscopes. Several different multicolored configurations of fluorescent ring stains and/or contrasting fluorescent stains are available. The sharp ring stains produce a striking visual representation of instrument misalignment or other aberrations, making them ideal reference standards.

  • Matched to laser lines and common filters
  • Confirm optical sectioning thickness
  • Test alignment and spectral separation

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FocalCheck Test Slides

FocalCheck fluorescence microscope test slides are specifically designed for calibrating fluorescence microscope systems and evaluating system and filter performance. Each slide contains 10 sample areas coated with proprietary fluorescent microspheres designed specifically for microscopy applications.
  • FocalCheck fluorescence microscope test slide #1 is ideal for alignment, intensity, and calibration
  • FocalCheck fluorescence microscope test slide #2 is ideal for evaluating spectral imaging systems
  • FocalCheck fluorescence microscope test slide #3 is useful for basic evaluation of filter performance

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A double-labeled microsphere from the FocalCheck DoubleGreen Fluorescent Microsphere Kit.

InSpeck and TetraSpeck Microspheres

InSpeck Microscope Image Intensity Calibration Kits contain microsphere suspensions for use as fluorescence intensity reference standards.

TetraSpeck Fluorescent Microspheres facilitate the chromatic registration of conventional fluorescence microscopes, confocal laser scanning microscopes, and associated image-processing equipment.

TetraSpeck beads are available in five diameters, spanning the range from subresolution to nearly cell-size particles. They are stained throughout with four different fluorescent dyes, yielding beads that each display four well-separated excitation/emission peaks.

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Four exposures of three TetraSpeck beads.

FluoCells Prepared Slides

FluoCells prepared microscope slides contain multilabeled cell or cryosection preparations for observation by epifluorescence or confocal microscopy. The multicolor staining in these cell preparations results in stunning, publication-quality images. The slides are especially useful for setting up microscopes and camera systems, and for assessing the capabilities of optical filter sets.

  • FluoCells Prepared Slide #1 (BPAE Cells with MitoTracker Red CMXRos, Alexa Fluor 488 Phalloidin, DAPI)
  • FluoCells Prepared Slide #2 (BPAE Cells with Mouse Anti-α-tubulin, BODIPY FL Goat Anti-Mouse IgG, Texas Red-X Phalloidin, DAPI)
  • FluoCells Prepared Slide #3 (Mouse Kidney Section with Alexa Fluor 488 WGA, Alexa Fluor 568 Phalloidin, DAPI)
  • FluoCells Prepared Slide #4 (Mouse Intestine Section with Alexa 350 WGA, Alexa Fluor 568 Phalloidin, SYTOX Green dye)
  • FluoCells Prepared Slide #6 (Muntjac Cells with Mouse Anti-OxPhos Complex V Inhibitor Protein, Alexa Fluor 555 Goat Anti-Mouse IgG, Alexa Fluor 488 Phalloidin, TO-PRO-3 dye)

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FluoCells prepared slide #1.

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Stylesheet for Classic Wide Template adjustments
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For Research Use Only. Not for use in diagnostic procedures.