Syringe adapter 300 has base member 310 and flange lock member 320. Flange lock member 320 is formed in generally arc shape as a whole so as to receive a cylinder flange inside. Flange lock member 320 has look hook 323 and engagement hook 324 formed thereon. Look hook 323 locks the cylinder flange by rotation of a syringe received in flange lock member 320 about its axis. Engagement hook 324 locks syringe adapter 300 to the apparatus so as not to release lock to the apparatus in the state in which the cylinder flange of the syringe is received in flange lock member 320.