Question

Which of the following will not be a factor governing the removal of substances through dialysis?

(a) Molecular weight

(b) Water solubility

(c) Disintegration time

(d) Protein binding

I have been asked this question during an interview for a job.

Question is taken from Pharmacokinetic in section Pharmacokinetic Drug Interactions & Basic Considerations of Drug Biotechnology

Answer 1

The correct choice is (c) Disintegration time

For explanation I would say: Disintegration time of a drug will be a factor for drug absorption, it will not directly affect the dialysis rate. Molecules with size less than 500 Dalton can be dialysed easily. Only water soluble drugs are able to be dialysed. Drugs binding to the plasma protein or the blood cells cannot be dialysed since dialysis is passive diffusion. Drug with large volume of distribution distributed throughout the body thus less readily removed through dialysis.