A metering pump , comprising: - a chamber having a proximal portion and a distal portion; - a piston (104; 504; 604) accommodated in the chamber (102; 502; 602) and being movable in the chamber (102; 502; 602); - a drive for driving the piston (104; 504; 604) reciprocally form a proximal dead center to a distal dead center in the chamber , wherein the distal dead center is located at the distal portion of the chamber and the proximal dead center is located at the proximal portion of the chamber ; - an outlet valve (116; 516; 616) located adjacent to the distal portion of the chamber , wherein the outlet valve (116; 516; 616) allows a flow of fluid from the chamber , if the piston (104; 504; 604) is moved in the distal direction, and blocks a fluid flow into the chamber , if the piston (104; 504; 604) is moved into the proximal direction; - a seal (122; 522; 622') located at the distal portion of the chamber , wherein the seal (122; 522; 622') seals the chamber , if the piston (104; 504; 604) is positioned at the distal dead center and contacts the seal (122; 522; 622'), wherein the seal (122; 522; 622') is located at the distal dead center position of the piston (104; 504; 604) and wherein the distal portion of the piston (104; 504; 604) compresses the seal (122; 522; 622') elastically in the distal dead center position of the piston (104; 504; 604); and - an inlet valve (114; 514; 614), wherein the inlet valve (114; 514; 614) allows a flow of fluid into the chamber , if the piston (104; 504; 604) is moved in the proximal direction, and blocks a fluid flow out of the chamber , if the piston (104; 504; 604) is moved in the distal direction. - a chamber having a proximal portion and a distal portion; - a piston (104; 504; 604) accommodated in the chamber (102; 502; 602) and being movable in the chamber (102; 502; 602); - a drive for driving the piston (104; 504; 604) reciprocally form a proximal dead center to a distal dead center in the chamber , wherein the distal dead center is located at the distal portion of the chamber and the proximal dead center is located at the proximal portion of the chamber ; - an outlet valve (116; 516; 616) located adjacent to the distal portion of the chamber , wherein the outlet valve (116; 516; 616) allows a flow of fluid from the chamber , if the piston (104; 504; 604) is moved in the distal direction, and blocks a fluid flow into the chamber , if the piston (104; 504; 604) is moved into the proximal direction; - a seal (122; 522; 622') located at the distal portion of the chamber , wherein the seal (122; 522; 622') seals the chamber , if the piston (104; 504; 604) is positioned at the distal dead center and contacts the seal (122; 522; 622'), wherein the seal (122; 522; 622') is located at the distal dead center position of the piston (104; 504; 604) and wherein the distal portion of the piston (104; 504; 604) compresses the seal (122; 522; 622') elastically in the distal dead center position of the piston (104; 504; 604); and - an inlet valve (114; 514; 614), wherein the inlet valve (114; 514; 614) allows a flow of fluid into the chamber , if the piston (104; 504; 604) is moved in the proximal direction, and blocks a fluid flow out of the chamber , if the piston (104; 504; 604) is moved in the distal direction. <EOS>