ELECTROCHEMICAL ANALYSIS IN PICOLITER MICROVIALS

Lithographically fabricated templates have been used to imprint picoli ter to femtoliter microvials in polystyrene. The clear microvials prod uced in conjunction with a transmission optical microscope and microma nipulators make it possible to handle volumes as small as 1 pt. Voltam metry has been carried out in these well-defined microenvironments wit h restriction of reagents near the electrode surface. Ferrocenecarboxy lic acid has been utilized to characterize the electrochemical respons e in these ultrasmall volumes. Sigmoidal voltammograms (0.4-2 V/s) are obtained for vial sizes down to 1 pL.