| 摘要 |
<p>The invention relates to apparatus for manipulating small quantities of liquid, comprising at least one test tube (1, 2) for accommodating the quantity of liquid, a cannula (10) which can be inserted into the vessel, and a control arrangement (6, 21) for controlling the system vessel and cannula in relation to one another in a manner such as to bring the cannula to the bottom of the vessel. In accordance with the invention, the cannula is provided with a suspension means (9,11, 12) which is connected to a mechanical or electronic sensor arrangement (22) which records pressure acting axially on the end of the cannula. When pressure is detected, the control arrangement halts further insertion of the cannula into the vessel.</p> |
