Positioning of dispensing means in fraction collector
View Patent ↗A method in a fraction collector for accurate positioning of a dispensing device with respect to wells of a micro plate in which prior to the dispensing a sensing device is moved over the micro plate the sensing device being able to detect the number of walls between the wells in the rows and columns of the micro plate.
1. A method for operating a fraction collector, said method comprising the steps of:
i) providing a liquid dispenser for dispensing into one or more of a plurality of receptacles each including a matrix of rows and columns of wells in a plate; and
providing a sensing device capable of sensing the positions of the wells;
ii) operating the sensing device to scan at least one of the rows or columns and thereby generating a signal corresponding to the number of wells in the scanned row(s) or column(s);
iii) sequentially dispensing fractions of liquid from the dispenser into a respective receptacle by displacing said receptacle relative to said dispenser; and
iv) using said signal for controlling said relative displacement of said dispenser.
2. The method of claim 1 , wherein said sensing device is integrated in said dispensing means.
3. The method of claim 1 , wherein at least one row and one column of said plate are scanned by said sensing device.
4. The method of claim 1 , wherein at least two rows and/or columns are scanned by said sensing device.
5. The method of claim 1 , wherein said plate is arranged in a cassette provided with a bar code equally readable by said sensing device.
6. The method of claim 1 , wherein said sensing device consists of an IR sender and IR detector.
7. A fraction collector comprising a combined sensing and dispensing head movable in x- and y-directions and a plurality of cassettes arranged in a cassette tray, said cassettes holding micro plates including liquid wells, said sensing and dispensing head being movable to detect the number of wells in the x- and/or y-directions, by moving across said wells, the head further providing a signal corresponding to the number of wells in at least one of said rows or columns and said signal being used for controlling the displacement of said head during dispensing.