One concrete data point for the thread. One practical note: write down what you did and when, before you need it. Reconstructing a timeline from memory three months later is how people end up unable to answer the one question that would have resolved it.
That is the short version; the long version is somebody else's post.
One thing that is still open after DebRD_ATL’s answer:
How long did you give it before you decided it was working?
Dr.GutHealth said:One practical note: write down what you did and when, before you need it.
I am going to disagree with the direction of travel here. The thread has converged on the tidiest answer rather than the best-supported one, and those are not the same thing.
Sigma-Aldrich — Research-Grade Standards
Certified reference materials, analytical reagents, and research-grade standards for peptide verification. Trusted by laboratories worldwide.
Shop Reference StandardsDr.GutHealth said:One practical note: write down what you did and when, before you need it.
That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.
Dr.GutHealth said:One practical note: write down what you did and when, before you need it.
That reframing is the part I needed. Printing the relevant bit and taking it with me.