GRADIENT-COATED ALUMINUM COLUMNS FOR GAS CHROMATOGRAPHY

WE PROPOSE TO EVALUATE AND REFINE A NOVEL GAS CHROMATOGRAPHIC COLUMN WITH THE FOLLOWING FEATURES: (1) A STATIONARY PHASE OF HIGH THERMAL STABILITY BONDED TO ALUMINUM, (2) A GRADIENT OF FILM THICKNESS OF STATIONARY PHASE TO PROVIDE BOTH HIGH SAMPLE CAPACITY AND HIGH RESOLVING POWER, AND (3) THE ABILITY TO PERFORM SIZE-EXCLUSION CHROMATOGRAPHY IN ADDITION TO PARTITION CHROMATOGRAPHY. THE COLUMNS WILL BE PREPARED BY ANODIZING THE INTERNAL SURFACE OF THE TUBING AND BONDING STATIONARY PHASES IRREVERSIBLY TO THE ANODIZED LAYER. PORES ARE PRODUCED IN THE ANODIZED LAYER, AND IT IS POSSIBLE TO CONTROL THE DEPTH AND DIAMETER OF THE PORES BY VARYING THE ANODIZATION CONDITIONS. DEEPER PORES (I.E., GREATER SURFACEAREA) CAN BE MADE AT THE INLET END OF THE COLUMN TO PROVIDE FOR A GREATER FILM THICKNESS OF STATIONARY PHASE. THE EFFECTIVE DIAMETER OF THE PORES CAN BE VARIED BY SELECTING STATIONARY PHASES WITH DIFFERENT MOLECULAR DIMENSIONS. THE COMBINATION OF ALL OF THESE FEATURES SHOULD EXPAND THE UTILITY OF GAS CHROMATOGRAPHY.