in the test sample the kit contains i 125 labeled anti ca 195 anti ca 195 coated beads ca 195 standards 0 10 30 60 90 and 120 u ca195 ml and instructions for use fifty microliters of standards or specimens are pipetted into the assigned tubes two hundred microliters of i 125 labeled anti ca 195 are then pipetted into all tubes one bead is placed into each tube the tubes are vortexed and then put on a horizontal rotator set at 170 rpm for two hours at room temperature the beads are then washed with 2 ml of wash solution three times and then read in a suitable well type gamma scintillation counter the following is an example of a procedure to manufacture crude ca 195 from human amniotic fluid human amniotic fluid is collected and immediately frozen for storage when ready to use the amniotic fluid is allowed to thaw to yield the desired quantity in weight every container is inspected for satisfactory physical characteristics all equipment is inspected for cleanliness and if needed equipment for final filtration is steam cleaned ca 195 radioimmunoassays are run as described in example 2 only samples which show greater than 800 u ml are accepted the amniotic fluid is filtered through cheesecloth and the weight recorded the ph of.