Cal-520®, sodium salt
Ordering information
Price | |
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Additional ordering information
Telephone | 1-800-990-8053 |
Fax | 1-800-609-2943 |
sales@aatbio.com | |
Quotation | Request |
International | See distributors |
Shipping | Standard overnight for United States, inquire for international |
Physical properties
Dissociation constant (Kd, nM) | 320 |
Molecular weight | 840.54 |
Solvent | Water |
Spectral properties
Excitation (nm) | 493 |
Emission (nm) | 515 |
Quantum yield | 0.751 |
Storage, safety and handling
H-phrase | H303, H313, H333 |
Hazard symbol | XN |
Intended use | Research Use Only (RUO) |
R-phrase | R20, R21, R22 |
Storage | Freeze (< -15 °C); Minimize light exposure |
UNSPSC | 12352200 |
Overview | ![]() ![]() |
Molecular weight 840.54 | Dissociation constant (Kd, nM) 320 | Excitation (nm) 493 | Emission (nm) 515 | Quantum yield 0.751 |
Cal-520® provides a robust homogeneous fluorescence-based assay tool for detecting intracellular calcium mobilization. Cal-520® AM is a new fluorogenic calcium-sensitive dye with a significantly improved signal to noise ratio and intracellular retention compared to the existing green calcium indicators (such as Fluo-3 AM and Fluo-4 AM). Cells expressing a GPCR or calcium channel of interest that signals through calcium can be preloaded with Cal-520® AM which can cross cell membrane. Once inside the cell, the lipophilic blocking groups of Cal-520™ AM are cleaved by esterases, resulting in a negatively charged fluorescent dye that stays inside cells. Its fluorescence is greatly enhanced upon binding to calcium. When cells stimulated with agonists, the receptor signals the release of intracellular calcium, which significantly increase the fluorescence of Cal-520®. The characteristics of its long wavelength, high sensitivity, and >100 times fluorescence enhancement, make Cal-520® AM an ideal indicator for the measurement of cellular calcium. The high S/N ratio and better intracellular retention make the Cal-520® calcium assay a robust tool for evaluating GPCR and calcium channel targets as well as for screening their agonists and antagonists. Cal-520® sodium or potassium salt is the hydrolyzed salt of Cal-520® AM in cells. It selectively binds to calcium ion, and has the fluorescence that is strongly dependent on calcium concentration.
Calculators
Common stock solution preparation
Table 1. Volume of Water needed to reconstitute specific mass of Cal-520®, sodium salt to given concentration. Note that volume is only for preparing stock solution. Refer to sample experimental protocol for appropriate experimental/physiological buffers.
0.1 mg | 0.5 mg | 1 mg | 5 mg | 10 mg | |
1 mM | 118.971 µL | 594.856 µL | 1.19 mL | 5.949 mL | 11.897 mL |
5 mM | 23.794 µL | 118.971 µL | 237.942 µL | 1.19 mL | 2.379 mL |
10 mM | 11.897 µL | 59.486 µL | 118.971 µL | 594.856 µL | 1.19 mL |
Molarity calculator
Enter any two values (mass, volume, concentration) to calculate the third.
Mass (Calculate) | Molecular weight | Volume (Calculate) | Concentration (Calculate) | Moles | ||||
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Spectrum
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Spectral properties
Excitation (nm) | 493 |
Emission (nm) | 515 |
Quantum yield | 0.751 |
Product Family
Name | Excitation (nm) | Emission (nm) | Quantum yield |
Cal-520®, potassium salt | 493 | 515 | 0.751 |
Cal-590™, sodium salt | 574 | 588 | 0.621 |
Cal-630™, sodium salt | 609 | 626 | 0.371 |
Images

Figure 1. ATP-stimulated calcium responses of endogenous P2Y receptor in CHO-K1 cells incubated with Cal-520™ AM (red curve), or Fluo-4 AM (blue curve) respectively with (left) or without probenecid (right) under the same conditions. CHO-K1 cells were seeded overnight at 50,000 cells per 100 µL per well in a Costar black wall/clear bottom 96-well plate. 100 µL of 5 µM Fluo-4 AM or Cal 520™ AM in HHBS (with or without probenecid) was added into the cells, and the cells were incubated at 37 °C for 1 hour. ATP (50 μL/well) was added using FlexSation to achieve the final indicated concentrations.
Citations
View all 94 citations: Citation Explorer
High hydrostatic pressure induces slow contraction in mouse cardiomyocytes
Authors: Yamaguchi, Yohei and Nishiyama, Masayoshi and Kai, Hiroaki and Kaneko, Toshiyuki and Kaihara, Keiko and Iribe, Gentaro and Takai, Akira and Naruse, Keiji and Morimatsu, Masatoshi
Journal: Biophysical Journal (2022)
Authors: Yamaguchi, Yohei and Nishiyama, Masayoshi and Kai, Hiroaki and Kaneko, Toshiyuki and Kaihara, Keiko and Iribe, Gentaro and Takai, Akira and Naruse, Keiji and Morimatsu, Masatoshi
Journal: Biophysical Journal (2022)
Advances in Two-Photon Scanning and Scanless Microscopy Technologies for Functional Neural Circuit Imaging
Authors: Schultz, Simon R and Copel, undefined and , Caroline S and Foust, Am and a J , undefined and Quicke, Peter and Schuck, Renaud
Journal: Proceedings of the IEEE (2017): 139--157
Authors: Schultz, Simon R and Copel, undefined and , Caroline S and Foust, Am and a J , undefined and Quicke, Peter and Schuck, Renaud
Journal: Proceedings of the IEEE (2017): 139--157
Interstitial cell modulation of pyeloureteric peristalsis in the mouse renal pelvis examined using FIBSEM tomography and calcium indicators
Authors: Hashitani, Hikaru and Nguyen, Michael J and Noda, Haruka and Mitsui, Retsu and Higashi, Ryuhei and Ohta, Keisuke and Nakamura, Kei-Ichiro and Lang, Richard J
Journal: Pflügers Archiv-European Journal of Physiology (2017): 1--17
Authors: Hashitani, Hikaru and Nguyen, Michael J and Noda, Haruka and Mitsui, Retsu and Higashi, Ryuhei and Ohta, Keisuke and Nakamura, Kei-Ichiro and Lang, Richard J
Journal: Pflügers Archiv-European Journal of Physiology (2017): 1--17
Extensive Ca 2+ leak through K4750Q cardiac ryanodine receptors caused by cytosolic and luminal Ca 2+ hypersensitivity
Authors: Uehara, Akira and Murayama, Takashi and Yasukochi, Midori and Fill, Michael and Horie, Minoru and Okamoto, Toru and Matsuura, Yoshiharu and Uehara, Kiyoko and Fujimoto, Takahiro and Sakurai, Takashi and others, undefined
Journal: The Journal of general physiology (2017): 199--218
Authors: Uehara, Akira and Murayama, Takashi and Yasukochi, Midori and Fill, Michael and Horie, Minoru and Okamoto, Toru and Matsuura, Yoshiharu and Uehara, Kiyoko and Fujimoto, Takahiro and Sakurai, Takashi and others, undefined
Journal: The Journal of general physiology (2017): 199--218
Synchronicity and Rhythmicity of Purkinje Cell Firing during Generalized Spike-and-Wave Discharges in a Natural Mouse Model of Absence Epilepsy Complex Spike Synchronicity during GSWDs
Authors: Kros, Lieke and Lindeman, S and er , undefined and Eelkman Rooda, Oscar HJ and Murugesan, Pavithra and Bina, Lorenzo and Bosman, Laurens WJ and De Zeeuw, Chris I and Hoebeek, Freek E
Journal: Frontiers in Cellular Neuroscience (2017): 346
Authors: Kros, Lieke and Lindeman, S and er , undefined and Eelkman Rooda, Oscar HJ and Murugesan, Pavithra and Bina, Lorenzo and Bosman, Laurens WJ and De Zeeuw, Chris I and Hoebeek, Freek E
Journal: Frontiers in Cellular Neuroscience (2017): 346
Simultaneous Measurement of Neural Activities of Acute Mouse Hippocampal Slices Using Multi-Electrode Array System and Laser Confocal Calcium Imaging
Authors: Hamasaki, Yuuta and Haba, Natsumi and Iwata, Naoki and Uno, Yoshiki and Saito, Minoru
Journal: Journal of Behavioral and Brain Science (2017): 68
Authors: Hamasaki, Yuuta and Haba, Natsumi and Iwata, Naoki and Uno, Yoshiki and Saito, Minoru
Journal: Journal of Behavioral and Brain Science (2017): 68
Ca 2+ signals initiate at immobile IP 3 receptors adjacent to ER-plasma membrane junctions
Authors: Thillaiappan, Nagendra Babu and Chavda, Alap P and Tovey, Stephen C and Prole, David L and Taylor, Colin W
Journal: Nature Communications (2017): 1505
Authors: Thillaiappan, Nagendra Babu and Chavda, Alap P and Tovey, Stephen C and Prole, David L and Taylor, Colin W
Journal: Nature Communications (2017): 1505
Mechanical loading disrupts osteocyte plasma membranes which initiates mechanosensation events in bone
Authors: Yu, Kanglun and Sellman, David P and Bahraini, Anoosh and Hagan, Mackenzie L and Elsherbini, Ahmed and Vanpelt, Kayce T and Marshall, Peyton L and Hamrick, Mark W and McNeil, Anna and McNeil, Paul L and others, undefined
Journal: Journal of Orthopaedic Research (2017)
Authors: Yu, Kanglun and Sellman, David P and Bahraini, Anoosh and Hagan, Mackenzie L and Elsherbini, Ahmed and Vanpelt, Kayce T and Marshall, Peyton L and Hamrick, Mark W and McNeil, Anna and McNeil, Paul L and others, undefined
Journal: Journal of Orthopaedic Research (2017)
Neonatal CX26 removal impairs neocortical development and leads to elevated anxiety
Authors: Su, Xin and Chen, Jing-Jing and Liu, Lin-Yun and Huang, Qian and Zhang, Li-Zhao and Li, Xiao-Yang and He, Xiang-Nan and Lu, Wenlian and Sun, Shan and Li, Huawei and others, undefined
Journal: Proceedings of the National Academy of Sciences (2017): 201613237
Authors: Su, Xin and Chen, Jing-Jing and Liu, Lin-Yun and Huang, Qian and Zhang, Li-Zhao and Li, Xiao-Yang and He, Xiang-Nan and Lu, Wenlian and Sun, Shan and Li, Huawei and others, undefined
Journal: Proceedings of the National Academy of Sciences (2017): 201613237
Flexible polygon-mirror based laser scanning microscope platform for multiphoton in-vivo imaging
Authors: Li, YX and Gautam, V and Brüstle, A and Cockburn, IA and Daria, VR and Gillespie, C and Gaus, K and Alt, C and Lee, WM
Journal: Journal of Biophotonics (2017)
Authors: Li, YX and Gautam, V and Brüstle, A and Cockburn, IA and Daria, VR and Gillespie, C and Gaus, K and Alt, C and Lee, WM
Journal: Journal of Biophotonics (2017)
Application notes
A Comparison of Fluorescent Red Calcium Indicators for Detecting Intracellular Calcium Mobilization in CHO Cells
A Meta-Analysis of Common Calcium Indicators
A New Red Fluorescent & Robust Screen Quest™ Rhod-4™ Ca2+Indicator for Screening GPCR & Ca2+ Channel Targets
A New Robust No-Wash FLIPR Calcium Assay Kit for Screening GPCR and Calcium Channel Targets
A Novel NO Wash Probeniceid-Free Calcium Assay for Functional Analysis of GPCR and Calcium Channel Targets
A Meta-Analysis of Common Calcium Indicators
A New Red Fluorescent & Robust Screen Quest™ Rhod-4™ Ca2+Indicator for Screening GPCR & Ca2+ Channel Targets
A New Robust No-Wash FLIPR Calcium Assay Kit for Screening GPCR and Calcium Channel Targets
A Novel NO Wash Probeniceid-Free Calcium Assay for Functional Analysis of GPCR and Calcium Channel Targets
FAQ
Are there any calcium indicators that don't require probenecid (PBC)?
Are there upgraded trypan blue derivatives for cell viability testing?
Can I intracellularly measure mitochondria calcium flux and changes in mitochondria membrane potential at the same time?
Do you offer any products for measuring intracellular calcium concentration or movement by flow cytometry?
How do I make an AM ester stock solution?
Are there upgraded trypan blue derivatives for cell viability testing?
Can I intracellularly measure mitochondria calcium flux and changes in mitochondria membrane potential at the same time?
Do you offer any products for measuring intracellular calcium concentration or movement by flow cytometry?
How do I make an AM ester stock solution?