logo
AAT Bioquest

Annexin V

Annexins are a family of proteins that bind to phospholipid membranes in the presence of calcium. Annexin V is a valuable tool for studying cell apoptosis. It is used as a probe to detect cells expressing phosphatidylserine on the cell surface, a feature found in apoptosis and other forms of cell death. There are a variety of parameters that can be used for monitoring cell viability. Annexin V-dye conjugates are widely used to monitor cell apoptosis by measuring the translocation of phosphatidylserine (PS). In apoptosis, PS is transferred to the outer leaflet of the plasma membrane. The appearance of phosphatidylserine on the cell surface is a universal indicator of the initial/intermediate stages of cell apoptosis and can be detected before morphological changes can be observed. This fluorescent Annexin V conjugate has spectral properties similar to Alexa Fluor® 350 (Alexa Fluor® 350 is the trademark of Invitrogen).

Example protocol

AT A GLANCE

Protocol Summary
  1. Prepare cells with test compounds (200 µL/sample).

  2. Add Annexin V conjugate assay solution.

  3. Incubate at room temperature for 30-60 minutes.

  4. Analyze with a flow cytometer or a fluorescence microscope.

Storage and Handling Conditions

The fluorescent annexin V conjugates are stored in a PBS buffer solution containing 0.1% bovine serum albumin (BSA) with a pH of 7.4. To ensure their stability, it is recommended that the solutions be stored at a temperature of -20°C and protected from light. Avoid exposing the fluorescent conjugates to repeated freeze-thaw cycles as this can have a negative effect on their integrity. These solutions can be stored for at least 6 months under the recommended conditions.

SAMPLE EXPERIMENTAL PROTOCOL

Prepare and Incubate Cells with Annexin V Conjugate
  1. Prepare an Annexin V-binding assay buffer: 10 mM HEPES, 140 mM NaCl, and 2.5 mM CaCl2, pH 7.4.

  2. Treat cells with test compounds for a desired period of time (e.g., 4-6 hours for Jurkat cells treated with staurosporine) to induce apoptosis.

  3. Centrifuge the cells to get 1-5×105 cells/tube.

  4. Resuspend cells in 200 μL of the Annexin V-binding assay buffer from Step 1.

  5. Add 2 μL of the Annexin V conjugate to the cells.

    Optional: Add a dead cell stain such as Propidium Iodide (Cat No. 17585) into the cells for necrosis cells.

  6. Incubate at room temperature for 30 to 60 minutes, protected from light.

  7. Add 300 μL of the Annexin V-binding assay buffer (from Step 1) to increase volume before analyzing the cells with
    a flow cytometer or fluorescence microscope.

  8. Monitor the fluorescence intensity by using a flow cytometer or a fluorescence microscope.

Flow Cytometer Protocol
  1. Quantify Annexin V conjugates binding by using a flow cytometer with appropriate filters.

    Note: It is not common to perform Annexin V binding flow cytometric analysis on adherent cells due to the possibility of membrane damage during cell detachment or harvesting. However, previous studies by Casiola-Rosen et al. and van Engelend et al. (refer to Refs 1 and 2) have demonstrated methods for using Annexin V in flow cytometry on adherent cell types.

Fluorescence Microscope Protocol
  1. Pipette the cell suspension from Step 6, rinse 1-2 times with Annexin V-binding assay buffer (Step 1), and then resuspend the cells with the Annexin V-binding assay buffer (Step 1).

  2. Add the cells on a glass slide that is covered with a glass cover slip.

    Note: For adherent cells, it is recommended to grow the cells directly on a cover slip. 

  3. After incubation with Annexin V conjugate (Step 6), rinse 1-2 times with Annexin V-binding assay buffer (Step 1), and add
    Annexin V-binding assay buffer (Step 1) back to the cover slip.

  4. Invert the cover slip on a glass slide and visualize the cells. The cells can also be fixed in 2% formaldehyde after incubation with Annexin V conjugate and visualized under a microscope with the appropriate filter set.

APPENDIX

References
  1. Pascal Clerc, Pauline Jeanjean, Nicolas Halalli, Michel Gougeon, Bernard Pipy, Julian Carrey, Daniel Fourmy, Véronique Gigoux. Journal of Controlled Release (2017).

  2. Hanshaw RG, Lakshmi C, Lambert TN, Johnson JR, Smith BD. Chembiochem, 6, 2214. (2005).

Spectrum

Product family

NameExcitation (nm)Emission (nm)Extinction coefficient (cm -1 M -1)Quantum yieldCorrection Factor (260 nm)Correction Factor (280 nm)
Annexin V-iFluor® 633 conjugate64065425000010.2910.0620.044
Annexin V-iFluor® 488 conjugate4915167500010.910.210.11
Annexin V-iFluor® 555 conjugate55757010000010.6410.230.14
Annexin V-iFluor® 594 conjugate58760320000010.5310.050.04
Annexin V-iFluor® 647 conjugate65667025000010.2510.030.03
Annexin V-iFluor® 680 conjugate68470122000010.2310.0970.094
Annexin V-iFluor® 750 conjugate75777927500010.1210.0440.039
Annexin V-iFluor® 700 conjugate69071322000010.2310.090.04

Citations

View all 6 citations: Citation Explorer
Cancer stem cells and somatic stem cells as potential new drug targets, prognosis markers, and therapy efficacy predictors in breast cancer treatment
Authors: Pershina, Olga and Ermakova, Natalia and Pakhomova, Angelina and Widera, Darius and Pan, Edgar and Zhukova, Mariia and Slonimskaya, Elena and Morozov, Sergey G and Kubatiev, Aslan and Dygai, Alexander and others,
Journal: Biomedicines (2021): 1223
Cancer Stem Cells and Somatic Stem Cells as Potential New Drug Targets, and Prognosis Markers, and Therapy Efficacy Predictors in Breast Cancer Treatment
Authors: Skurikhin, Evgenii and Pershina, Olga and Ermakova, Natalia and Pakhomova, Angelina and Widera, Darius and Pan, Edgar and Zhukova, Mariia and Morozov, Sergey and Kubatiev, Aslan and Dygai, Alexander
Journal: (2021)
Genetic Factors as the Basis of Sex Differences in Damage to Lung Endothelium and Regulation of Angiogenesis Cells in Modeling Pulmonary Emphysema in C57BL/6 Mice with Dyslipidemia and Hyperglycemia
Authors: Skurikhin, EG and Pakhomova, AV and Pershina, OV and Ermakova, NN and Krupin, VA and Pan, ES and Sandrikina, LA and Putrova, OD and Zhukova, MA and Kurochkina, IV and others,
Journal: Bulletin of Experimental Biology and Medicine (2021): 326--331
Pericytes and Smooth Muscle Cells Circulating in the Blood as Markers of Impaired Angiogenesis during Combined Metabolic Impairments and Lung Emphysema
Authors: Pakhomova, AV and Pershina, OV and Ermakova, NN and Krupin, VA and Pan, ES and Putrova, OD and Khmelevskaya, ES and Vaizova, OE and Pozdeeva, AS and Dygai, AM and others,
Journal: Bulletin of Experimental Biology and Medicine (2020): 334--340

References

View all 32 references: Citation Explorer
Gold fluorescent annexin A5 as a novel apoptosis detection tool
Authors: Kurschus FC, Pal PP, Baumler P, Jenne DE, Wiltschi B, Budisa N.
Journal: Cytometry A (2009): 626
Glycogen synthase kinase-3 and Omi/HtrA2 induce annexin A2 cleavage followed by cell cycle inhibition and apoptosis
Authors: Wang CY, Lin YS, Su WC, Chen CL, Lin CF.
Journal: Mol Biol Cell (2009): 4153
Evaluation of annexin V and Calcein-AM as markers of mononuclear cell apoptosis during human immunodeficiency virus infection
Authors: Palma PF, Baggio GL, Spada C, Silva RD, Ferreira SI, Treitinger A.
Journal: Braz J Infect Dis (2008): 108
Measurement of annexin V uptake and lactadherin labeling for the quantification of apoptosis in adherent Tca8113 and ACC-2 cells
Authors: Hu T, Shi J, Jiao X, Zhou J, Yin X.
Journal: Braz J Med Biol Res (2008): 750
Detection of apoptosis induced by new type gosling viral enteritis virus in vitro through fluorescein annexin V-FITC/PI double labeling
Authors: Chen S, Cheng AC, Wang MS, Peng X.
Journal: World J Gastroenterol (2008): 2174
Page updated on October 8, 2024

Ordering information

Price
Conjugate
Unit size
Catalog Number
Quantity
Add to cart

Additional ordering information

Telephone1-800-990-8053
Fax1-800-609-2943
Emailsales@aatbio.com
InternationalSee distributors
Bulk requestInquire
Custom sizeInquire
Technical SupportContact us
Purchase orderSend to sales@aatbio.com
ShippingStandard overnight for United States, inquire for international
Request quotation

Physical properties

Molecular weight

~36000

Solvent

Water

Spectral properties

Correction Factor (260 nm)

0.83

Correction Factor (280 nm)

0.23

Extinction coefficient (cm -1 M -1)

200001

Excitation (nm)

345

Emission (nm)

450

Quantum yield

0.951

Storage, safety and handling

H-phraseH303, H313, H333
Hazard symbolXN
Intended useResearch Use Only (RUO)
R-phraseR20, R21, R22

Storage

Freeze (< -15 °C); Minimize light exposure
UNSPSC12352200

Platform

Flow cytometer

Excitation355 or 405 nm laser
Emission450, 40 nm filter
Instrument specification(s)Pacific Blue channel

Fluorescence microscope

ExcitationDAPI filter set
EmissionDAPI filter set
Recommended plateBlack wall, clear bottom
The binding activity of Annexin V-iFluor® 350 conjugate to phosphatidylserine (PS) residues in Jurkat cells. Jurkat cells were treated without (Green) or with 1 μM staurosporine (Red) at 37 °C for 4 hours and then labeled with Annexin V-iFluor® 350 conjugate for 30 minutes. The fluorescence intensity was measured using an ACEA NovoCyte flow cytometer in the Pacific Blue channel.
The binding activity of Annexin V-iFluor® 350 conjugate to phosphatidylserine (PS) residues in Jurkat cells. Jurkat cells were treated without (Green) or with 1 μM staurosporine (Red) at 37 °C for 4 hours and then labeled with Annexin V-iFluor® 350 conjugate for 30 minutes. The fluorescence intensity was measured using an ACEA NovoCyte flow cytometer in the Pacific Blue channel.
The binding activity of Annexin V-iFluor® 350 conjugate to phosphatidylserine (PS) residues in Jurkat cells. Jurkat cells were treated without (Green) or with 1 μM staurosporine (Red) at 37 °C for 4 hours and then labeled with Annexin V-iFluor® 350 conjugate for 30 minutes. The fluorescence intensity was measured using an ACEA NovoCyte flow cytometer in the Pacific Blue channel.