[peptideismylife]

Hey guys,
Hi colleagues,

I have troubles to calculate the yield of a peptide synthesis. The point is that I dont understand how I have to use the substitution of the aminoacid in the resin. I will put you one example:

Peptide that I want to synthesize: Lys-Ser-Ala-Wang Resin
Fmoc-Ala-Wang Resin (substitution 0.72 mmol/g)

the goal is to synthesize 0.1 mmol peptide so it means that I have to use 0.139 g of the a.a.-resin (m=0.1mmol peptide/0.72 mmol/g = 0.139g).

So how I have to calculate the theoretical yield?

Thanks for advance

[karbon]

If you want to synthesize 0.1 mmol of the tripeptide you first have to figure out how much yield you get per step right? First would be deprotection step, then react with Fmoc-Ser, deprotect and then Fmoc-Lys right? If all these steps each are 95% yield you would do 4 steps right? That would give an overall yield of ~81% to get the Fmoc-Lys-Ser-Ala-Wang resin, which means you would need to start with ~ 0.124 mmol wang resin.

If you just want the theoretical yield then its easy, because you start with 0.1 mmol... so the theoretical yield in the end should br 0.1mmol....