Abstract: Cartesian robots and methods for proper alignment are provided. More specifically, the invention uses reflective spheres and a laser to locate specific points that can then be used to determine correction factors.

Abstract: A method for automated loading of liquid sample to a liquid chromatography testing device is provided including installing a disposable tip on a probe, moving the probe with an automated liquid handler to a loading position proximate to a sample, and drawing a sample into the disposable tip. The probe is then moved to an injection position proximate an injection port, and the sample is injected from the disposable tip into the injection port. Also provided are the novel injection ports. After injection of the sample, the disposable tip is then removed from the probe. These steps may be repeated a plurality of times to sequentially load a plurality of samples. An exemplary method of the invention is directed to use with a liquid chromatography apparatus. An apparatus for assisting in the removal of the disposable tip is also provided.

Abstract: A probe drive system of a precision liquid handler sequentially inserts probe tips of a multiple probe array into a locator well at a known position on a locator bed. The position of each probe tip is determined by driving the probe tip into contact with points on the side wall of the locator well and sensing the contracts. The positions of the probe tips are mapped and checked for skew of the probe array. The probe tip positions are overlaid to determine probe tip scatter. If a probe tip is excessively misaligned, it is inserted into the locator well and driven against the side wall to bend the probe and reduce the misalignment of the probe tip. The center of the probe tip scatter is determined and is used by the probe drive system as a global correction factor. Probe tips with known positions are inserted into spaced apart locator wells to detect skew of the locator bed.

Abstract: A piston carrier supports an elongated, slender piston rod for reciprocation in a pump cylinder to pump fluid into and out of the cylinder. The piston rod is made of a material such as sapphire or zircon and has a diameter less than about ten millimeters, and the pump can provide flows of from about 50 nanoliters to about 250 microliters per minute at pressures of several hundred bars. A drive motor rotates a threaded screw and a drive nut of a drive system applies a linear drive force to the piston carrier. A ball and socket connection between the drive system and the piston carrier avoids the need for precise alignment to prevent breakage of the fragile piston. A magnet in the socket holds the ball in place and avoids the need for a spring or other mechanical holder. The socket also includes a ring of a low reluctance material surrounding the ball to increase the magnetic retention force.

Abstract: A probe drive system of a precision liquid handler sequentially inserts probe tips of a multiple probe array into a locator well at a known position on a locator bed. The position of each probe tip is determined by driving the probe tip into contact with points on the side wall of the locator well and sensing the contracts. The positions of the probe tips are mapped and checked for skew of the probe array. The probe tip positions are overlaid to determine probe tip scatter. If a probe tip is excessively misaligned, it is inserted into the locator well and driven against the side wall to bend the probe and reduce the misalignment of the probe tip. The center of the probe tip scatter is determined and is used by the probe drive system as a global correction factor. Probe tips with known positions are inserted into spaced apart locator wells to detect skew of the locator bed.

Abstract: A sample is fractioned prior to chromatographic separation by a multidimensional purification routine including sequential first and second solid phase extraction procedures having different first and second extraction dimensions such as ph and ion strength. The method is automated and performed with a software programmable automated liquid handler system. The first extraction routine produces step graded fractions that are extracted into step graded subfractions in the second extraction routine. The subfractions are separated in an HPLC column with the output columns going to a detector such as a mass spectrometer or a ultra violet detector.

Abstract: A liquid handler system includes a probe transport system that has a plurality of carriages movable along a support. Each of the carriages carries a second support, which in turn carries a third support. A plurality of probes are linked to a movable holder on the third supports. Through operation of a liquid handler system of the invention, liquid may be selectively delivered to one or more of a plurality of liquid receptacles.

Abstract: A piston carrier supports an elongated, slender piston rod for reciprocation in a pump cylinder to pump fluid into and out of the cylinder. The piston rod is made of a material such as sapphire or zircon and has a diameter less than about ten millimeters, and the pump can provide flows of from about 50 nanoliters to about 250 microliters per minute at pressures of several hundred bars. A drive motor rotates a threaded screw and a drive nut of a drive system applies a linear drive force to the piston carrier. A ball and socket connection between the drive system and the piston carrier avoids the need for precise alignment to prevent breakage of the fragile piston. A magnet in the socket holds the ball in place and avoids the need for a spring or other mechanical holder. The socket also includes a ring of a low reluctance material surrounding the ball to increase the magnetic retention force.

Abstract: A probe drive system of a precision liquid handler sequentially inserts probe tips of a multiple probe array into a locator well at a known position on a locator bed. The position of each probe tip is determined by driving the probe tip into contact with points on the side wall of the locator well and sensing the contracts. The positions of the probe tips are mapped and checked for skew of the probe array. The probe tip positions are overlaid to determine probe tip scatter. If a probe tip is excessively misaligned, it is inserted into the locator well and driven against the side wall to bend the probe and reduce the misalignment of the probe tip. The center of the probe tip scatter is determined and is used by the probe drive system as a global correction factor. Probe tips with known positions are inserted into spaced apart locator wells to detect skew of the locator bed.

Abstract: A number of racks make up a stack. An upper rack includes releasable catches received into orifices in the next lower rack to releasably attach the two racks to one another. A loader and receptacle cooperate with one another to release the bottommost rack from the stack and deposit it into the receptacle where pipette cones held therein are accessible for use. The bottom rack is placed into the loader where it is held by catches engaging ribs of the rack. The stack of racks with the loader attached is placed onto the receptacle. The stack of racks is pressed downwardly. The downward movement releases the bottom rack from the loader. At the same time, studs projecting up from the bottom of the receptacle engage catches of the second-from-the-bottom rack and free the bottom rack. The bottom rack now rests freely in the receptacle.

Abstract: A probe drive system of a precision liquid handler sequentially inserts probe tips of a multiple probe array into a locator well at a known position on a locator bed. The position of each probe tip is determined by driving the probe tip into contact with points on the side wall of the locator well and sensing the contracts. The positions of the probe tips are mapped and checked for skew of the probe array. The probe tip positions are overlaid to determine probe tip scatter. If a probe tip is excessively misaligned, it is inserted into the locator well and driven against the side wall to bend the probe and reduce the misalignment of the probe tip. The center of the probe tip scatter is determined and is used by the probe drive system as a global correction factor. Probe tips with known positions are inserted into spaced apart locator wells to detect skew of the locator bed.

Abstract: A rack for pipette cones (in particular multichannel cones) includes orifices in a line forming at least one row along at least an alignment direction and a support surface adapted to support cones housed in the orifices. The rack provides for simultaneous access to at least some of the cones in the row. The support surface has a generally convex transverse outline along the alignment direction.

Abstract: A locator bed has nests where sample well containing plates are held and positioned for accessing by probes moved by an X-Y-Z positioning system. Each nest includes stop posts at two sides of a rectangular base of a plate, and biasing posts at the opposed two sides. The stop posts and the biasing posts have tapered upper guide portions for guiding a descending plate into position and cylindrical lower portions receiving the base of the plate in a seated position. The stop posts are located on the surface of the locator bed by conical seat portions. The biasing posts are placed over studs fastened to the bed surface, and hoop springs are captured between the studs and the biasing posts.

Abstract: A thermal transfer comb includes numerous upwardly extending pins received in spaces around and between the sample containing wells of a well plate. Peltier effect modules are in contact with a base panel of the thermal transfer comb to apply heat to or remove heat from the comb. A heat sink and fan transfer heat from or to the modules.

Abstract: An automated liquid handler includes a probe assembly with a probe foot that can be moved down against the top of sample containers of a variety of sizes and shapes defined by racks, tubes or plates. A seal at the bottom of the foot provides a seal between the foot and the containers making it possible to prepare a SPE sample by using positive, probe introduced pressure within the containers to force liquid samples out through media at the bottom of the container. The foot seal is self sealing without the need for adhesives or other potential contaminates, and is removeably mounted to the probe foot.

Abstract: A multiple probe liquid handler includes a syringe pump assembly with multiple syringe pumps communicating with the probes. A carriage movable with respect to a fixed support base carries syringe pump pistons moving within syringe pump cylinders secured to the base. A drive system including a single drive motor has a single drive point connection to the carriage for moving the carriage and operating the syringe pumps in order to draw fluid into or discharge fluid from the multiple probes. A linear motion support assembly includes spaced rails attached to the support base and slides attached to the carriage and riding along the rails. The assembly includes two parallel rails and three slides, one riding along one rail and two riding along the other rail, providing an inexpensive yet imbalance tolerant three point support.