Radioactive D- and L-alanine hydrochloride in 10 -5 molar dimethylformamide solution was adsorbed by d - and l -quartz to the extent of 20 to 30 percent, as shown by radioactivity loss. d -Quartz preferentially adsorbs D-alanine and l -quartz adsorbs L-alanine. The extent of asymmetric preferenti…