Cal-770™, potassium salt

Ordering information

Price
Catalog Number
Unit Size
Quantity

Add to cart

Additional ordering information

Telephone	1-800-990-8053
Fax	1-800-609-2943
Email	sales@aatbio.com
International	See distributors
Bulk request	Inquire
Custom size	Inquire
Shipping	Standard overnight for United States, inquire for international

Physical properties

Dissociation constant (K_d, nM)	850
Molecular weight	1688.58
Solvent	Water

Spectral properties

Excitation (nm)	758
Emission (nm)	783

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 SDS Protocol

Molecular weight

1688.58

Dissociation constant (K_d, nM)

850

Excitation (nm)

758

Emission (nm)

783

Calcium measurement is critical for numerous biological investigations. Fluorescent probes that show spectral responses upon binding calcium have enabled researchers to investigate changes in intracellular free calcium concentrations by using fluorescence microscopy, flow cytometry, fluorescence spectroscopy and fluorescence microplate readers. Cal-770™ is a near infrared (NIR) calcium indicator with maximum emission at ~775 nm. It is the only fluorescent calcium indicator with excitation and emission longer than 700 nm with a moderate calcium affinity of Kd ~850 nM. Cal-770™ is one of the very few calcium indicators that can be potentially used for in vivo imaging since it has a NIR fluorescence.

Example protocol

SAMPLE EXPERIMENTAL PROTOCOL

Calcium calibration can be carried out by measuring the fluorescence intensity of the salt form (25 to 50 µM in fluorescence microplate readers) of the indicators in solutions with precisely known free Ca²⁺ concentrations. Calibration solutions can be used based on 30 mM MOPS EGTA Ca²⁺ buffer. In general, water contains trace amount of calcium ion. It is highly recommended to use 30 mM MOPS + 100 mM KCl, pH 7.2 as buffer system. One can simply make a 0 and 39 µM calcium stock solutions as listed below, and these 2 solutions are used to make a serial solution of different Ca²⁺ concentrations.
A: 0 µM calcium: 30 mM MOPS + 100 mM KCl, pH 7.2 buffer + 10 mM EGTA
B: 39 µM calcium: 30 mM MOPS + 100 mM KCl, pH 7.2 buffer + 10 mM EGTA + 10 mM CaCl₂
To determine either the free calcium concentration of a solution or the Kd of a single-wavelength calcium indicator, the following equation is used:
[Ca]_Free = K_d [F - F_min] / [F_max - F]
Where F is the fluorescence intensity of the indicator at a specific experimental calcium level, F_min is the fluorescence intensity in the absence of calcium and F_max is the fluorescence intensity of the calciumsaturated probe.
The dissociation constant (K_d) is a measure of the affinity of the probe for calcium. The calcium-binding and spectroscopic properties of fluorescent indicators vary quite significantly in cellular environments compared to calibration solutions. In situ response calibrations of intracellular indicators typically yield K_d values significantly higher than in vitro determinations. In situ calibrations are performed by exposing loaded cells to controlled Ca²⁺ buffers in the presence of ionophores such as A-23187, 4-bromo A-23187 and ionomycin. Alternatively, cell permeabilization agents such as digitonin or Triton® X-100 can be used to expose the indicator to the controlled Ca²⁺ levels of the extracellular medium. The fluorescence can be measured at Ex/Em = 750/790 nm.

Calculators

Common stock solution preparation

Table 1. Volume of Water needed to reconstitute specific mass of Cal-770™, potassium 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	59.221 µL	296.107 µL	592.214 µL	2.961 mL	5.922 mL
5 mM	11.844 µL	59.221 µL	118.443 µL	592.214 µL	1.184 mL
10 mM	5.922 µL	29.611 µL	59.221 µL	296.107 µL	592.214 µL

Molarity calculator

Enter any two values (mass, volume, concentration) to calculate the third.

Mass (Calculate)		Molecular weight		Volume (Calculate)		Concentration (Calculate)		Moles
	/		=		x		=

Spectrum

Open in Advanced Spectrum Viewer

Spectral properties

Excitation (nm)	758
Emission (nm)	783

Product Family

Name	Excitation (nm)	Emission (nm)	Quantum yield
Cal-590™, potassium salt	574	588	0.62¹
Cal-630™, potassium salt	609	626	0.37¹
Cal-520®, potassium salt	492	515	0.75¹
Cal-520FF™, potassium salt	492	515	0.75¹
Cal-520N™, potassium salt	492	515	0.75¹
Cal-500™, potassium salt	388	482	0.48¹
Cal-670™, potassium salt	667	680	-

Images

Figure 1. Cal-770 was incubated with buffer that contains different concentration of free Ca2+. The fluorescence was monitored.

Citations

View all 10 citations: Citation Explorer

Calreticulin regulates TGF-β1-induced epithelial mesenchymal transition through modulating Smad signaling and calcium signaling
Authors: Wu, Yanjiao and Xu, Xiaoli and Ma, Lunkun and Yi, Qian and Sun, Weichao and Tang, Liling
Journal: The International Journal of Biochemistry & Cell Biology (2017)

Monosialoganglioside 1 may alleviate neurotoxicity induced by propofol combined with remifentanil in neural stem cells
Authors: Lu, Jiang and Yao, Xue-qin and Luo, Xin and Wang, Yu and Chung, Sookja Kim and Tang, He-xin and Cheung, Chi Wai and Wang, Xian-yu and Meng, Chen and Li, Qing and others, undefined
Journal: Neural Regeneration Research (2017): 945

Obtaining spontaneously beating cardiomyocyte-like cells from adipose-derived stromal vascular fractions cultured on enzyme-crosslinked gelatin hydrogels
Authors: Yang, Gang and Xiao, Zhenghua and Ren, Xiaomei and Long, Haiyan and Ma, Kunlong and Qian, Hong and Guo, Yingqiang
Journal: Scientific Reports (2017): 41781

Dexmedetomidine reduces hypoxia/reoxygenation injury by regulating mitochondrial fission in rat hippocampal neurons
Authors: Liu, Jia and Du, Qing and Zhu, He and Li, Yu and Liu, Maodong and Yu, Shoushui and Wang, Shilei
Journal: Int J Clin Exp Med (2017): 6861--6868

Di (2-ethylhexyl) phthalate-induced apoptosis in rat INS-1 cells is dependent on activation of endoplasmic reticulum stress and suppression of antioxidant protection
Authors: Sun, Xia and Lin, Yi and Huang, Qiansheng and Shi, Junpeng and Qiu, Ling and Kang, Mei and Chen, Yajie and Fang, Chao and Ye, Ting and Dong, Sijun
Journal: Journal of cellular and molecular medicine (2015): 581--594

The effect of mitochondrial calcium uniporter on mitochondrial fission in hippocampus cells ischemia/reperfusion injury
Authors: Zhao, Lantao and Li, Shuhong and Wang, Shilei and Yu, Ning and Liu, Jia
Journal: Biochemical and biophysical research communications (2015): 537--542

Role of mitochondrial calcium uniporter in regulating mitochondrial fission in the cerebral cortexes of living rats
Authors: Liang, Nan and Wang, Peng and Wang, Shilei and Li, Shuhong and Li, Yu and Wang, Jinying and Wang, Min
Journal: Journal of Neural Transmission (2014): 593--600

Propofol and remifentanil at moderate and high concentrations affect proliferation and differentiation of neural stem/progenitor cells
Authors: Li, Qing and Lu, Jiang and Wang, Xianyu and others, undefined
Journal: Neural regeneration research (2014): 2002

Fungus induces the release of IL-8 in human corneal epithelial cells, via Dectin-1-mediated protein kinase C pathways.
Authors: Peng, Xu-Dong and Zhao, Gui-Qiu and Lin, Jing and Jiang, Nan and Xu, Qiang and Zhu, Cheng-Cheng and Qu, Jain-Qiu and Cong, Lin and Li, Hui
Journal: International journal of ophthalmology (2014): 441--447

Increased expression of cell adhesion molecule 1 by mast cells as a cause of enhanced nerve--mast cell interaction in a hapten-induced mouse model of atopic dermatitis
Authors: Hagiyama, M and Inoue, T and Furuno, T and Iino, T and Itami, S and Nakanishi, M and Asada, H and Hosokawa, Y and Ito, A
Journal: British Journal of Dermatology (2013): 771--778

References

View all 53 references: Citation Explorer

A flow cytometric comparison of Indo-1 to fluo-3 and Fura Red excited with low power lasers for detecting Ca(2+) flux
Authors: Bailey S, Macardle PJ.
Journal: J Immunol Methods (2006): 220

Functional fluo-3/AM assay on P-glycoprotein transport activity in L1210/VCR cells by confocal microscopy
Authors: Orlicky J, Sulova Z, Dovinova I, Fiala R, Zahradnikova A, Jr., Breier A.
Journal: Gen Physiol Biophys (2004): 357

Comparison of human recombinant adenosine A2B receptor function assessed by Fluo-3-AM fluorometry and microphysiometry
Authors: Patel H, Porter RH, Palmer AM, Croucher MJ.
Journal: Br J Pharmacol (2003): 671

Measurement of the dissociation constant of Fluo-3 for Ca2+ in isolated rabbit cardiomyocytes using Ca2+ wave characteristics
Authors: Loughrey CM, MacEachern KE, Cooper J, Smith GL.
Journal: Cell Calcium (2003): 1

A sensitive method for the detection of foot and mouth disease virus by in situ hybridisation using biotin-labelled oligodeoxynucleotides and tyramide signal amplification
Authors: Zhang Z, Kitching P.
Journal: J Virol Methods (2000): 187

Kinetics of onset of mouse sperm acrosome reaction induced by solubilized zona pellucida: fluorimetric determination of loss of pH gradient between acrosomal lumen and medium monitored by dapoxyl (2-aminoethyl) sulfonamide and of intracellular Ca(2+) chang
Authors: Rockwell PL, Storey BT.
Journal: Mol Reprod Dev (2000): 335

MRP2, a human conjugate export pump, is present and transports fluo 3 into apical vacuoles of Hep G2 cells
Authors: Cantz T, Nies AT, Brom M, Hofmann AF, Keppler D.
Journal: Am J Physiol Gastrointest Liver Physiol (2000): G522

Use of co-loaded Fluo-3 and Fura Red fluorescent indicators for studying the cytosolic Ca(2+)concentrations distribution in living plant tissue
Authors: Walczysko P, Wagner E, Albrechtova JT.
Journal: Cell Calcium (2000): 23

[Ca2+]i following extrasystoles in guinea-pig trabeculae microinjected with fluo-3 - a comparison with frog skeletal muscle fibres
Authors: Wohlfart B., undefined
Journal: Acta Physiol Scand (2000): 1

Determination of the intracellular dissociation constant, K(D), of the fluo-3. Ca(2+) complex in mouse sperm for use in estimating intracellular Ca(2+) concentrations
Authors: Rockwell PL, Storey BT.
Journal: Mol Reprod Dev (1999): 418