Hello,

I and a group of hobbyists have managed to acquire a used Shimadzu GC-17A and QP5000A GCMS unit from the mid-90s. Unfortunately, it didn't come with the PC software, so I'm wondering, does anyone have access to a copy of the PC software for it that we could examine and decompile?

We're currently trying to pull firmware off the device so that we can reverse engineer the protocol it uses, and write a driver for it able to run on a modern operating system, but having desktop-side software available would definitely make the process easier. If we do successfully reverse engineer it, we'll post what we've managed to get on GitHub.

Yes ninhydrin reacts with a lot of amino containing stuff.

It should not absorb strongly.  Its presence may change R_f values of other compounds, depending upon the solvent system.  I have sometimes thought about removing it from TLC samples, but I have not actually done so.

Please read the forum rules, you have to show your efforts at answering the question to receive help.

Technically you should start by writing the reaction equation, after that calculations are rather easy.

That being said I am not convinced the obvious reaction that you can find here and there by googling is correct, my bet is that the process of thermal decomposition of KSCN is not something that follows a well defined, stoichiometric path, which makes the result of simple calculations unrealistic.

Acidifying the solution is a sure way of speeding up the decomposition.

Buffers composition is typically calculated using Henderson-Hasselbalch equation, see examples here: https://www.chembuddy.com/buffers-composition-calculation