Patent ID: 7703485

Claim:
A self-sealing reaction vessel having an access opening, such that the reaction vessel may be repeatedly accessed by a fluid transfer mechanism, and subsequently self-sealed, comprising: a cap sized to fit over the reaction vessel access opening, said cap having an access port located above said reaction vessel access opening when said cap is attached to said reaction vessel, wherein said cap has an internal surface which faces the reaction vessel, and an external surface, which faces away from the reaction vessel, wherein the reaction vessel is a serum vial having a neck portion and a body portion, wherein the body portion of the reaction vessel has a greater diameter than the neck portion of the reaction vessel, wherein the reaction vessel is further comprised of a septum which is mounted to the cap external surface, and wherein the septum covers the access port; a fastening mechanism for fastening said cap to the reaction vessel, wherein said fastening mechanism comprises a threaded portion formed on said internal surface of said cap and a mating threaded portion formed on an external surface of said reaction vessel adjacent said reaction vessel access opening; a ball sized to fit over said cap access port, wherein the ball is comprised of a magnetizable material such that a portion of said ball seats partially in said cap access port on said cap internal surface, sealing said cap access port; and a ring magnet which produces a magnetic field, wherein said ring magnet is mounted to said cap on said cap external surface, and spaced from said cap such that the magnetic field is sufficient to hold said ball in said cap access port such as said ball does not directly contact said ring magnet, and to reseat said ball in said cap access port after said reaction vessel is accessed.