mixtures of peptoids are provided . the subject peptoid mixtures comprise at least five non - homopolymeric polymers of differing sequences having a selected number of monomer units . the polymers of the subject mixtures are preferably selected from the group of compounds of the general formula : x a -- n -- x b , x a -- n -- x b , x a -- n -- x b , x a -- n -- x b , x a -- n -- x b , x a -- n -- xb , xa -- n -- x b , x a -- n -- x b and x a -- n x b , where each r is independently a side chain capable of interaction with a protein , carbohydrate , lipid or nucleic acid ; n is an integer from 2 to 50 , inclusive ; and x a and x b are each independently h , lower alkyl , lower aryl , aralkyl , lower acyl , a polypeptide of 1 - 100 amino acids , or an effector molecule capable of exhibiting biological activity .