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QXY21 NHS ester [equivalent to QSY-21 NHS ester]
Ordering information
| Price | |
| Catalog Number | |
| Unit Size | |
| Quantity |
Additional ordering information
| Telephone | 1-800-990-8053 |
| Fax | 1-800-609-2943 |
| sales@aatbio.com | |
| International | See distributors |
| Bulk request | Inquire |
| Custom size | Inquire |
| Shipping | Standard overnight for United States, inquire for international |
Physical properties
| Molecular weight | 892.90 |
| Solvent | DMSO |
Spectral properties
| Absorbance (nm) | 660 |
| Correction Factor (280 nm) | 0.32 |
| Extinction coefficient (cm -1 M -1) | 890001 |
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 |  SDSProtocol |
Molecular weight 892.90 | Absorbance (nm) 660 | Correction Factor (280 nm) 0.32 | Extinction coefficient (cm -1 M -1) 890001 |
QXY21 is the same molecule to QSY-21 acid (ThermoFisher). QSY-21 has a broad and intense absorption at ~661 nm maxima with no detectable fluorescence, making it useful as an acceptor in fluorescence resonance energy transfer (FRET) applications. It is a common long-wavelength quencher to best pair with Cy5, Alexa Fluor 647, iFluor 647 or other spectrally similar fluorescent dyes.
Calculators
Common stock solution preparation
Table 1. Volume of DMSO needed to reconstitute specific mass of QXY21 NHS ester [equivalent to QSY-21 NHS ester] 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 | 111.995 µL | 559.973 µL | 1.12 mL | 5.6 mL | 11.199 mL |
| 5 mM | 22.399 µL | 111.995 µL | 223.989 µL | 1.12 mL | 2.24 mL |
| 10 mM | 11.199 µL | 55.997 µL | 111.995 µL | 559.973 µL | 1.12 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
| Absorbance (nm) | 660 |
| Correction Factor (280 nm) | 0.32 |
| Extinction coefficient (cm -1 M -1) | 890001 |
Product Family
| Name | Excitation (nm) | Emission (nm) | Extinction coefficient (cm -1 M -1) | Quantum yield | Correction Factor (260 nm) | Correction Factor (280 nm) |
| XFD488 NHS Ester *Same Structure to Alexa Fluor™ 488 NHS Ester* | 499 | 520 | 71000 | 0.921 | 0.30 | 0.11 |
| XFD350 NHS Ester *Same Structure to Alexa Fluor™ 350 NHS Ester* | 343 | 441 | 19000 | - | 0.25 | 0.19 |
| XFD532 NHS Ester *Same Structure to Alexa Fluor™ 532 NHS Ester* | 534 | 553 | 81000 | 0.611 | 0.24 | 0.09 |
| XFD594 NHS Ester *Same Structure to Alexa Fluor™ 594 NHS Ester* | 590 | 618 | 90000 | 0.661 | 0.43 | 0.56 |
| XFD555 NHS Ester *Same Structure to Alexa Fluor™ 555 NHS Ester* | 553 | 568 | 150000 | 0.11 | 0.08 | 0.08 |
| XFD647 NHS Ester *Same Structure to Alexa Fluor™ 647 NHS Ester* | 650 | 671 | 239000 | 0.331 | 0.00 | 0.03 |
| XFD680 NHS Ester *Same Structure to Alexa Fluor™ 680 NHS Ester* | 681 | 704 | 184000 | 0.361 | 0.00 | 0.05 |
| XFD700 NHS Ester *Same Structure to Alexa Fluor™ 700 NHS Ester* | 696 | 719 | 192000 | 0.251 | 0.00 | 0.07 |
| XFD750 NHS Ester *Same Structure to Alexa Fluor™ 750 NHS Ester* | 752 | 776 | 240000 | 0.121 | 0.00 | 0.04 |
Show More (10) | ||||||
Images
Figure 1. QSY-21 NHS esters (or succinimidyl esters) readily reacts with the primary amines (R-NH2) of proteins, amine-modified oligonucleotides, and other amine-containing molecules. The resulting dye conjugates are quite stable.
Figure 2. Chemical structure for QXY21 NHS ester [equivalent to QSY-21 NHS ester].
Citations
View all 12 citations: Citation Explorer
A Sensitive Near-Infrared Fluorescent Sensor for Mitochondrial Hydrogen Sulfide
Authors: Ji, A., Fan, Y., Ren, W., Zhang, S., Ai, H. W.
Journal: ACS Sens (2018): 992-997
Authors: Ji, A., Fan, Y., Ren, W., Zhang, S., Ai, H. W.
Journal: ACS Sens (2018): 992-997
Imaging intracellular quantum dots: fluorescence microscopy and transmission electron microscopy
Authors: Szymanski, C. J., Yi, H., Liu, J. L., Wright, E. R., Payne, C. K.
Journal: Methods Mol Biol (2013): 21-33
Authors: Szymanski, C. J., Yi, H., Liu, J. L., Wright, E. R., Payne, C. K.
Journal: Methods Mol Biol (2013): 21-33
Family of enhanced photoacoustic imaging agents for high-sensitivity and multiplexing studies in living mice
Authors: de la Zerda, A., Bodapati, S., Teed, R., May, S. Y., Tabakman, S. M., Liu, Z., Khuri-Yakub, B. T., Chen, X., Dai, H., Gambhir, S. S.
Journal: ACS Nano (2012): 4694-701
Authors: de la Zerda, A., Bodapati, S., Teed, R., May, S. Y., Tabakman, S. M., Liu, Z., Khuri-Yakub, B. T., Chen, X., Dai, H., Gambhir, S. S.
Journal: ACS Nano (2012): 4694-701
Reversible off-on fluorescence probe for hypoxia and imaging of hypoxia-normoxia cycles in live cells
Authors: Takahashi, S., Piao, W., Matsumura, Y., Komatsu, T., Ueno, T., Terai, T., Kamachi, T., Kohno, M., Nagano, T., Hanaoka, K.
Journal: J Am Chem Soc (2012): 19588-91
Authors: Takahashi, S., Piao, W., Matsumura, Y., Komatsu, T., Ueno, T., Terai, T., Kamachi, T., Kohno, M., Nagano, T., Hanaoka, K.
Journal: J Am Chem Soc (2012): 19588-91
Visualizing mechanical tension across membrane receptors with a fluorescent sensor
Authors: Stabley, D. R., Jurchenko, C., Marshall, S. S., Salaita, K. S.
Journal: Nat Methods (2011): 64-7
Authors: Stabley, D. R., Jurchenko, C., Marshall, S. S., Salaita, K. S.
Journal: Nat Methods (2011): 64-7
Pyrenebutyrate Leads to Cellular Binding, Not Intracellular Delivery, of Polyarginine-Quantum Dots
Authors: Jablonski, A. E., Kawakami, T., Ting, A. Y., Payne, C. K.
Journal: J Phys Chem Lett (2010): 1312-1315
Authors: Jablonski, A. E., Kawakami, T., Ting, A. Y., Payne, C. K.
Journal: J Phys Chem Lett (2010): 1312-1315
A comparative study of the binding of QSY 21 and Rhodamine 6G fluorescence probes to DNA: structure and dynamics
Authors: Kabelac, M., Zim and l, F., Fessl, T., Chval, Z., Lankas, F.
Journal: Phys Chem Chem Phys (2010): 9677-84
Authors: Kabelac, M., Zim and l, F., Fessl, T., Chval, Z., Lankas, F.
Journal: Phys Chem Chem Phys (2010): 9677-84
Evaluation of glucose sensitive affinity binding assay entrapped in fluorescent dissolved-core alginate microspheres
Authors: Chaudhary, A., Raina, M., Harma, H., Hanninen, P., McShane, M. J., Srivastava, R.
Journal: Biotechnol Bioeng (2009): 1075-85
Authors: Chaudhary, A., Raina, M., Harma, H., Hanninen, P., McShane, M. J., Srivastava, R.
Journal: Biotechnol Bioeng (2009): 1075-85
Dissolved core alginate microspheres as "smart-tattoo" glucose sensors
Authors: Chaudhary, A., Raina, M., McShane, M. J., Srivastava, R.
Journal: Conf Proc IEEE Eng Med Biol Soc (2009): 4098-101
Authors: Chaudhary, A., Raina, M., McShane, M. J., Srivastava, R.
Journal: Conf Proc IEEE Eng Med Biol Soc (2009): 4098-101
Tumor-specific detection of an optically targeted antibody combined with a quencher-conjugated neutravidin "quencher-chaser": a dual "quench and chase" strategy to improve target to nontarget ratios for molecular imaging of cancer
Authors: Ogawa, M., Kosaka, N., Choyke, P. L., Kobayashi, H.
Journal: Bioconjug Chem (2009): 147-54
Authors: Ogawa, M., Kosaka, N., Choyke, P. L., Kobayashi, H.
Journal: Bioconjug Chem (2009): 147-54
References
View all 1 references: Citation Explorer
Synthesis and characterization of a small, membrane-permeant, caspase-activatable far-red fluorescent peptide for imaging apoptosis
Authors: Bullok K, Piwnica-Worms D.
Journal: J Med Chem (2005): 5404
Authors: Bullok K, Piwnica-Worms D.
Journal: J Med Chem (2005): 5404