Abstract: A method for capturing a substance having an anionic substituent by contacting a substance having an anionic substituent with a zinc complex such that the substance binds to the zinc complex, the zinc complex being represented by a formula (I): wherein each R is the same or different from each other and each R represents H; an alkyl group having 1 to 16 carbon atoms; an acyl group, a carboxyalkyl group, an acylalkyl group, a carbamoylalkyl group, a cyanoalkyl group, a hydroxyalkyl group, an aminoalkyl group or a haloalkyl group, wherein an alkyl portion of the acyl group, the carboxyalkyl group, the acylalkyl group, the carbamoylalkyl group, the cyanoalkyl group, the hydroxyalkyl group, the aminoalkyl group and the haloalkyl group has 1 to 16 carbon atoms; a carboxyl group; a carbamoyl group; a hydroxyl group; a cyano group; an amino group; or a halogeno group.

Abstract: A zinc complex represented by formula (I-0): {wherein R may be the same or different from each other and represents H; an alkyl group having 1 to 16 carbon atoms; an acyl group, a carboxyalkyl group, an acylalkyl group, a carbamoylalkyl group, a cyanoalkyl group, a hydroxyalkyl group, an aminoalkyl group or a haloalkyl group (here, a carbon number at an alkyl portion of these groups is 1 to 16); a carboxyl group; a carbamoyl group; a hydroxyl group; a cyano group; an amino group or; a halogeno group (provided that all are Hs are excluded)} which is capable of capturing a substance having an anionic substituent.