GB1014462A - Multiple pipetting apparatus - Google Patents

Abstract

1,014,462. Multiple pipetting apparatus. P. J. L. SEQUEIRA. Aug. 20, 1964 [Aug. 24, 1963], No. 33611/63. Heading B1X. [Also in Division B8] A member 108 carrying a row of pipetting tubes 112, Fig. 4, is movable to engage tubes 112 with any one of a plurality of rows of. receptacles 230 which are carried on a support 101 which is movable longitudinally on base 100 under member 108, tubes 112 each being connected to a separate syringe 200, Fig. 9, the plungers of which are operated in unison by handle 133 to draw liquids from one row of receptacles and expel measured quantities into other rows, an interlock means 115, 116, 117 preventing lowering of member 108 unless tubes 112 align with a row of receptacles. In use, racks 231 of test tubes 230 are clamped in place on tray 124 by slidable partitions 126 and clamps 128. Locating blocks 117 are clamped to rail 116, which moves with support 101, so that pin 115 can descend between adjacent blocks 117 only when tubes 112 align with a row of receptacles 230. When support 101 is so positioned marks are made on a programme card 130 adjacent pointer 131. In a typical operation, two rows of tubes 230 contain liquids which are successively drawn into tubes 112, then ejected into a further row to ensure proper mixing, then drawn up again and distributed to several other rows in different quantities. Standard quantities of diluent may be added subsequently to obtain samples diluted to different extents. Adjustable stops 134, Fig. 7 (not shown), indicate and limit movement of handle 133 to determine quantities of liquids drawn up and expelled. Member 108 is raised and lowered by handle 132, carried on movable support 101, by means of a movement-compensated pulley system, Fig. 5 (not shown). With support 101 in its far right position, member 108 is able to descend below the normal lower level and tubes 112 dip in a wash trough 142, Fig. 8 (not shown), which is fed intermittently with water from bottle 141, and has an immersion heater. Either cold water is run past the ends of tubes 112 to clean them, or a semi-automatic hot-wash is employed, controlled by a timer, Fig. 11 (not shown), and the tubes are moved up and down, by handle 132, in boiling water, and finally the plungers of syringes 200 are fully retracted (Fig. 9) and air is blown from pump 149 through drying flask 210 through the polythene tubing 113 and P.T.F.E. tubes 112. In another embodiment the pipetting tubes 32, Fig. 2B, are carried on one arm 31 of an L-shaped member whose other, tubular, arm 30 encloses the tubing 33, connecting tubes 32 to the syringes, and pivots on base 10 to effect engagement of tubes 32 with receptacles 23, whenever a locking pin 63 allows such engagement by itself engaging a slot 59 on the movable carriage 11. Carriage 11, in addition to test tubes 23, carries baths 24, 25 for receiving waste and containing diluent for drawing into tubes 32 respectively, and two plates, Fig. 3A (not shown), having rows of blind holes which form eighty more receptacles. It is within the scope of the invention to have a stationary receptacle support over which the pipetting tubes move.