What are people’s views on the minimum acceptable purity for research peptides?

[bluewater]

Is there a generally accepted minimum purity percentage that you consider acceptable before you’ll use a peptide for research?

Does it depend on the specific peptide?

For example:

• Is 95% acceptable for some peptides but not others?
  
• Do you expect 98%+ or 99%+ for certain compounds?

I’m interested in hearing what standards experienced researchers use in practice, and more importantly why. If you have data, references, or real-world experience that shaped your opinion, I’d really appreciate you sharing it.

Personally many of my peps have tested at 99%+ which I obviously consider to be good, but I have had one kit test at 96.5% and another kit at 98.3%. So now I question where do I draw the line.