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TWO-PRO™ 3 [equivalent to TO-PRO®-3] *5 mM DMSO Solution* *CAS 157199-63-8*
TWO-PRO™-3 is chemically equivalent to TO-PRO®-3 (TO-PRO® is the trademark of Invitrogen). TWO-PRO™-3 is a carbocyanine dimer with far-red fluorescence similar to Cy® 5 dyes. It is cell-impermeant and easily distinguished from fluorescein and rhodamine as a nuclear counterstain and dead cell indicator. It is non-fluorescent in the absence of nucleic acids, and generates a very bright fluorescence signal upon binding to DNA. TWO-PRO™-3 gives strong and selective nuclear staining in cultured cells and in paraffin sections. Simultaneous labeling with cell-permeable Nuclear Green™ LCS1 dye and cell-impermeant TWO-PRO™-3 can be used to assess cell viability. TWO-PRO™-3 and Nuclear Green™ both have much greater extinction coefficients than that of DNA-bound propidium iodide.
Example protocol
PREPARATION OF WORKING SOLUTION
TWO-PRO™-3 working solution
Make TWO-PRO™-3 working solution in Hanks with 20 mM Hepes buffer (HH buffer) or buffer of your choice at your desired concentration.Note In initial experiments, it may be best to try several dye concentrations to determine the optimal concentration that yields the desired result. High dye concentration tends to cause nonspecific staining of other cellular structures.
SAMPLE EXPERIMENTAL PROTOCOL
Caution: The following protocol can be adapted for most cell types. Growth medium, cell density, the presence of other cell types and factors may influence staining. Residual detergent on glassware may also affect staining of many organisms, and cause brightly stained material to appear in solutions with or without cells present.
- Grow and treat cells as desired.
- Remove the cell culture medium.
- Add TWO-PRO™-3 working solution (1 to 10 µM) into the cells (either suspension or adherent cells), and stain the cells for 15 to 60 minutes.
- Remove the dye working solution and add HH buffer or buffer of your choice.
- Analyze the cellular staining with a fluorescence microscope using Cy5 filter.
Spectrum
Product family
| Name | Excitation (nm) | Emission (nm) | Extinction coefficient (cm -1 M -1) | Quantum yield |
| TWO-PRO™ 1 [equivalent to TO-PRO®-1] *5 mM DMSO Solution* *CAS 157199-59-2* | 515 | 531 | 628001 | 0.251 |
Citations
View all 2 citations: Citation Explorer
Synergistic Activity and Mechanism of Sanguinarine with Polymyxin B against Gram-Negative Bacterial Infections
Authors: Qiao, Luyao and Zhang, Yu and Chen, Ying and Chi, Xiangyin and Ding, Jinwen and Zhang, Hongjuan and Han, Yanxing and Zhang, Bo and Jiang, Jiandong and Lin, Yuan
Journal: Pharmaceutics (2024): 70
Authors: Qiao, Luyao and Zhang, Yu and Chen, Ying and Chi, Xiangyin and Ding, Jinwen and Zhang, Hongjuan and Han, Yanxing and Zhang, Bo and Jiang, Jiandong and Lin, Yuan
Journal: Pharmaceutics (2024): 70
A lysosomal regulatory circuit essential for the development and function of microglia
Authors: Iyer, Harini and Shen, Kimberle and Meireles, Ana M and Talbot, William S
Journal: Science advances (2022): eabp8321
Authors: Iyer, Harini and Shen, Kimberle and Meireles, Ana M and Talbot, William S
Journal: Science advances (2022): eabp8321
References
View all 42 references: Citation Explorer
Daptomycin exerts rapid bactericidal activity against Bacillus anthracis without disrupting membrane integrity
Authors: Xing YH, Wang W, Dai SQ, Liu TY, Tan JJ, Qu GL, Li YX, Ling Y, Liu G, Fu XQ, Chen HP.
Journal: Acta Pharmacol Sin (2014): 211
Authors: Xing YH, Wang W, Dai SQ, Liu TY, Tan JJ, Qu GL, Li YX, Ling Y, Liu G, Fu XQ, Chen HP.
Journal: Acta Pharmacol Sin (2014): 211
Quantification of Candida albicans by flow cytometry using TO-PRO((R))-3 iodide as a single-stain viability dye
Authors: Kerstens M, Boulet G, Pintelon I, Hellings M, Voeten L, Delputte P, Maes L, Cos P.
Journal: J Microbiol Methods (2013): 189
Authors: Kerstens M, Boulet G, Pintelon I, Hellings M, Voeten L, Delputte P, Maes L, Cos P.
Journal: J Microbiol Methods (2013): 189
A silicon cell cycle in a bacterial model of calcium phosphate mineralogenesis
Authors: Linton KM, Tapping CR, Adams DG, Carter RD, Shore RC, Aaron JE.
Journal: Micron (2013): 419
Authors: Linton KM, Tapping CR, Adams DG, Carter RD, Shore RC, Aaron JE.
Journal: Micron (2013): 419
Pulsed electromagnetic field affects intrinsic and endoplasmatic reticulum apoptosis induction pathways in MonoMac6 cell line culture
Authors: Kaszuba-Zwoinska J, Chorobik P, Juszczak K, Zaraska W, Thor PJ.
Journal: J Physiol Pharmacol (2012): 537
Authors: Kaszuba-Zwoinska J, Chorobik P, Juszczak K, Zaraska W, Thor PJ.
Journal: J Physiol Pharmacol (2012): 537
Determination of the drug-DNA binding modes using fluorescence-based assays
Authors: Williams AK, Dasilva SC, Bhatta A, Rawal B, Liu M, Korobkova EA.
Journal: Anal Biochem (2012): 66
Authors: Williams AK, Dasilva SC, Bhatta A, Rawal B, Liu M, Korobkova EA.
Journal: Anal Biochem (2012): 66
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