A catheter with a distal end having a member formed from a hydrophilic composition
is provided. The hydrophilic composition expands upon contact with an aqueous fluid
to move the member from a quiescent state to an expanded state. The member may
provide an open passageway in the quiescent state and be capable for forming a
fluid tight seal by action of expansion of the hydrophilic composition. In such
a case the member acts as a valve for permitting or preventing fluid flow through
the catheter.
