Pipetting Apparatus for Aspiration and Dispensation of a Metering Fluid

• US 20090277285A1
• Filed: 05/05/2009
• Published: 11/12/2009
• Est. Priority Date: 05/06/2008
• Status: Active Grant

• Current Assignee: Hamilton Bonaduz AG (Hamilton Company)
• Original Assignee: Hamilton Bonaduz AG (Hamilton Company)
• Inventors: Schelling, Patrick, Panzer, Armin
• Granted Patent: US 8,245,586 B2
• Time in Patent Office: Days
• US Class Current: 73/864.130
• CPC Class Codes: B01L 2200/146 Employing pressure sensors
• CPC Class Codes: B01L 2200/147 Employing temperature sensors
• CPC Class Codes: B01L 2300/0627 Sensor or part of a sensor is integrated
• CPC Class Codes: B01L 2400/0478 pistons
• CPC Class Codes: B01L 3/0217 of the plunger pump type medical syringes A61M

Abstract

For aspiration and dispensation of a metering fluid, a pipetting apparatus comprises a work fluid which differs from the former, the work fluid being accommodated in a work space with a variable volume which extends along a channel axis and, with reference to the latter, is formed by a piston-cylinder system at least along an axial section of the channel axis, having a cylinder which delimits the work space along a cylinder section in the radial direction and a piston which delimits the work space in a first axial direction, the cylinder and the piston being arranged so that they can move with respect to each other such that the piston-cylinder system has an axial longitudinal end region for metering, which is open for aspiration and dispensation, and an axial longitudinal end region for work which is closed by the piston, the piston being designed as an outer piston and surrounding the cylinder on the outside in the longitudinal end region for work of the piston-cylinder system.

Claims

1. Pipetting apparatus for aspiration and dispensation of a metering fluid with the aid of a work fluid which differs from the former, the work fluid being accommodated in a work space with a variable volume which extends along a channel axis and, with reference to the latter, is formed by a piston-cylinder system at least along an axial section of the channel axis, having a cylinder which delimits the work space along a cylinder section in the radial direction and a piston which delimits the work space in a first axial direction, the cylinder and the piston being arranged so that they can move with respect to each other such that the piston-cylinder system has an axial longitudinal end region for metering, which is open for aspiration and dispensation, and an axial longitudinal end region for work which is closed by the piston, the piston being designed as an outer piston and surrounding the cylinder on the outside in the longitudinal end region for work of the piston-cylinder system, characterized in that the piston accommodates a sensor which is designed to acquire at least one state variable of the work fluid, preferably the pressure of the latter.

2. Pipetting apparatus according to claim 1,

characterized in that a radially inner surface of the piston lies opposite a radially outer surface of the cylinder in a cylinder end region for work in the vicinity of the longitudinal end region for work of the piston-cylinder system, with a seal being provided on at least one of the two surfaces which butts against the respective other surface in order to seal the piston and the cylinder against one another.

3. Pipetting apparatus according to claim 2,

characterized in that the piston has a hollow which, with respect to the channel axis and when observed in the assembled state, is delimited in the radial direction by a piston skirt running about the channel axis and in the first axial direction by a piston head, and which is open in a second axial direction which is counter to the first axial direction.

4. Pipetting apparatus according to claim 3,

characterized in that the cylinder end region for work is accommodated in the hollow of the piston such that it can undergo relative motion.

5. Pipetting apparatus according to claim 3,

characterized in that a piston wall which delimits the hollow has an opening at which the sensor for acquiring the state variable is provided.

6. Pipetting apparatus according to claim 5,

characterized in that the sensor closes off the opening.

7. Pipetting apparatus according to claim 3,

characterized in that the sensor forms part of a piston wall which delimits the hollow of the piston.

8. Pipetting apparatus according to claim 5, characterized in that the sensor is arranged in the region of the piston head or forms part of the latter.

9. Pipetting apparatus according to claim 8, characterized in that the piston is made from at least two parts, with a casing part with at least one through-hole and with a cover part which is connected to the casing part in such a fashion that it closes off the at least one through-hole on one side.

10. Pipetting apparatus according to claim 9,

characterized in that at least one sensor for acquiring a state variable of the work fluid is provided on the cover part, preferably at a point which is axially aligned with the through-hole in the assembled state of the apparatus.

11. Pipetting apparatus according to claim 1, characterized in that it has a pipette head with a multiplicity of work spaces which are preferably arranged like a matrix.

12. Pipetting apparatus according to claim 11,

characterized in that a sensor for acquiring a state variable of the work fluid is assigned to each work space.

13. Pipetting apparatus according to claim 11, characterized in that a radially inner surface of the piston lies opposite a radially outer surface of the cylinder in a cylinder end region for work in the vicinity of the longitudinal end region for work of the piston-cylinder system, with a seal being provided on at least one of the two surfaces which butts against the respective other surface in order to seal the piston and the cylinder against one another, the piston has a hollow which, with respect to the channel axis and when observed in the assembled state, is delimited in the radial direction by a piston skirt running about the channel axis and in the first axial direction by a piston head, and which is open in a second axial direction which is counter to the first axial direction, the piston is made from at least two parts, with a casing part with at least one through-hole and with a cover part which is connected to the casing part in such a fashion that it closes off the at least one through-hole on one side and the casing part is a perforated plate.

14. Pipetting apparatus according to claim 11, characterized in that radially inner surface of the piston lies opposite a radially outer surface of the cylinder in a cylinder end region for work in the vicinity of the longitudinal end region for work of the piston-cylinder system, with a seal being provided on at least one of the two surfaces which butts against the respective other surface in order to seal the piston and the cylinder against one another, the piston has a hollow which, with respect to the channel axis and when observed in the assembled state, is delimited in the radial direction by a piston skirt running about the channel axis and in the first axial direction by a piston head, and which is open in a second axial direction which is counter to the first axial direction, the piston is made from at least two parts, with a casing part with at least one through-hole and with a cover part which is connected to the casing part in such a fashion that it closes off the at least one through-hole on one side and a multiplicity of state variable sensors are arranged, preferably like a matrix, on the cover part, preferably on an end face of the latter.