At pH 7.4, the Proportion of uncharged basic drugs
The pKa (or conjugate acid) can help you determine the proportion of a basic medication that remains uncharged at certain pH levels. The pKa refers to the pH at the drug is half-protonated and half-uncharged. The pH 7.4 will uncharge 12.6% of a basic drug having a pKa 10. (Brouwer, Vermeulen 2019). The reason pH 7.4 has a lower pKa than 10, it is likely that the drug will remain uncharged at pH 7.4. When estimating the percentage of uncharged drug, it is important to take into account pH. With pH increasing, so does the percentage of uncharged drugs. Basic drugs tend to remain in uncharged forms at higher pHs. (Chaudhuri and al. 2016). At pH 10, for example, approximately 80% would remain uncharged. It is therefore important to take into account the pH of the solution in order to determine the percentage of uncharged basic drugs.