what is the difference between pka and pi
Isoelectric point For an amino acid with only one amine and one carboxyl group, the pI can be calculated from the mean of the pKas of this molecule.[4]
Profitability index Profitability index (PI), also known as profit investment ratio (PIR) and value investment ratio (VIR), is the ratio of payoff to investment of a proposed project. It is a useful tool for ranking projects because it allows you to quantify the amount of value created per unit of investment.