Syringe for taking samples of body fluid for analysis has a connecting system (18) for attaching a single-use sampling unit (14) to the plunger (20). Independent claims are also included for: (a) a similar syringe in which the sampling unit is fitted with a sampling needle (58) (b) a portable diagnostic apparatus incorporating the syringe (c) taking samples of body fluid for analysis using the syringe and (d) apparatus for taking samples of body fluid for analysis using disposable test units in which the sample is taken using a needle.
