elutions Flashcards
what are elutions used for
used on dat pos samples to detect Ab post transfusion
a solution of Ab will be taken off the cell
how is an acid elution done
decreased pH disrupts bonds between antigen and antibody
steps of an acid elution
- add acid to elute antibody from cells
- centrifuge and recover supernatant
- add buffer to supernatant
why is a buffer added to an acid elution
it will restore the pH,
without buffer Ab will not bind in acid
how is an elution done with heat
it denatures protein structure of antigen so antibodies are released
what are some methods of a heat elution
landsteiner miller heat 56 degrees
lui-freeze thaw
organic solvents elution
disrupts bonds between antigen and antibody by decreasing surface tension / dissolves lipid membrane
what are some organic solvents that can be used for an elution
- ether
- xylene
- dichloromethane
what is the difference between a partial elution and a regular elution
partial elution is a dissociation, cell saving elution method
detects the antigen rather than the antibody on the cell
what enzymes can be used for a dissociation methtod
- EDTA glycine acid
- Chloroquine Diphosphate
- ZZAP/ W.A.R.M
- modified heat 45 degrees
EDTA glycine acid
destroys kell antigens
ZZAP/WARM
contains papain and DTT
papain destroys MNS, Duffy, Chido & Rodgers
DTT destroys kell
will enhance Rh groups
why is modifies heat not used
historical method, would have to go back an treat more
what is the process of performing an elution
- QC
- Elutions: save the last wash and perform antibody screen -> should be neg, if pos QC failed
- Dissociation: perform a DAT -> should be neg
