Trypsin should be fine. You should however take care for EDTA, if your trypsin solution contains EDTA. The binding of annexin to phosphatidylserine is calcium ion dependent. If you do not remove the EDTA after trypsinization (wash cells) your signal will be weak as EDTA will bind the calcium and therefore prevent annexin from binding to phosphatidylserine.   

trypsin is just fine for harvesting HCT-116 cells for annexin V assay. I did it before with no issues. 

If you still want then you can use Accutase instead of trypsin. Good Luck

I have also used trypsin to harvest my adherent cells (primary human melanocytes, keratinocytes and fibroblasts) and have had no problems to run the Annexin V/PI FACS protocol. After you pellet the cells following trypsinization (making sure to neutralize the trypsin), just do a single wash in 1X PBS before staining the cells.

I also have test Annexin V/PI double staining for HCT-116 cells before, and I have collected the cells as usual. that's mean I harvest cells and trypsinize it with no any interference with the results. 

Hi Emily,

...All of the above and: If you are afraid of trypsin artifacts, you want to use a negative control (e.g. untreated), and a positive control (e.g. staurosporin treated). You may also want to optimize your trypsination time (as short as possible) to have as little artifact as possible.

Hope that helps

Same here I have used trypsin for harvesting cells and performed Annexin V staining as well as DAPI, ethidium bromide/acridine orange staining for apoptosis assay without any issue.  

Trypsin should be fine. You should however take care for EDTA, if your trypsin solution contains EDTA. The binding of annexin to phosphatidylserine is calcium ion dependent. If you do not remove the EDTA after trypsinization (wash cells) your signal will be weak as EDTA will bind the calcium and therefore prevent annexin from binding to phosphatidylserine.   

Should be fine but if you're worried and want an alternative, annexin/PI staining can be performed on adherent cultures and analzyed by fluorescence microscopy, eliminating the need for trypsinizing. Just grow your cells up on a cover slip or chamber slide and stain them directly. 

I used to use this procedure:

Seed 6 well plates from 0.175 x 106 to 0.25 x 106 cells per well in complete media, depending on length of assay.  Allow cells to grow overnight.

 Change media in each well before adding the treatment.  This gets rid of cells that are already dead.

 Harvest cells at the desired time point as follows:  Remove media to a conical tube.  Wash 1x in PBS and remove the PBS to the conical tube.  Trypsinize, stop with media and remove the cells to the same conical tube.  Centrifuge 5 minutes at 1500 rpm.  Wash once in cold PBS.  Centrifuge again at 1500 rpm.  Resuspend the pellet in Annexin Binding Buffer to ~1.0x 106 cells/ml. (About 0.5-1.0 ml of buffer depending on the size of the pellet.)

 Transfer 100ml of resuspended cells into a clear 5 ml Falcon tube (cat# REF 352054).  Add 5ml annexin V conjugate, incubate for 5 minutes at room temperature in the dark.

 Add 21 ml of 5mg/ml propidium iodide to the Falcon tube.  Incubate another 5 minutes at room temperature in the dark.

 Add 400ml Annexin Binding Buffer to each tube and place on ice.  The samples are now ready for FACS analysis.

 Annexin Binding Buffer:

10mM HEPES

140mM NaCl

2.5mM CaCl2

pH to 7.4