Abstract: Chromatographic systems for size exclusion chromatography (SEC) are provided that comprise an inlet, an outlet, an analytic column having a first interior volume that has a first length and a first cross-sectional area normal to the first length, the first interior volume containing a first stationary phase, and a guard column having a second interior volume that has a second length and a second cross-sectional area normal to the second length, the second interior volume containing a second stationary phase. The inlet is in fluid communication with the guard column, the guard column is in fluid communication with the analytic column, and the analytic column is in fluid communication with the outlet. Moreover, the second length is smaller than the first length, and the second cross-sectional area is smaller than the first cross-sectional area.

Abstract: Provided are devices and methods for sample collection and processing. A tubular body has a chamber closed at a first end by a thin penetrable barrier and open at a second end opposite the first end. The tubular body further includes a partition that divides the chamber into two adjacent compartments, wherein a first compartment of the two adjacent compartments has the partition facing opposite the open end of the chamber and a second compartment of the two adjacent compartments has the partition facing opposite the closed end of the chamber. The partition has one or more holes to allow passage of fluid from the first compartment into the second compartment. A tracking identification may be permanently affixed to the first end of the tubular body.