The science behind the ELISA test Used to

The science behind the ELISA test • Used to detect the presence of antigen (Neisseria meningitidis) in a sample • Different methods exist; antigen detection ELISA is often used to detect disease agents before the body has had a chance to produce antibodies Bio. Rad Animation also use Sumanas Animation Indirect method both links are on Haiku

Step 1: Step 2: Antigens in sample bind to the sides of the wells Step 3: Primary antibody binds to the specific antigen Step 4: Secondary antibody (conjugated to an enzyme) binds to primary antibody Substrate reacts with enzyme to produce a color change

ELISA Results • ELISA produces qualitative results indicating (+) or (-) for the presence of antibodies • Results can also be quantified based on the concentration

Serial Dilutions

ELISA: Day 1 Prepare concentration standard by performing a serial dilution. 100 μl antigen 50 μl PBS diluent 50 μl … X

ELISA: Day 1 • Prepare test strip for two assigned patients • Wait 5 minutes • Fill with wash buffer & pour out • Refill both strips with wash buffer overnight…

Assigned patients by Group Patients: #1 – Sue #2 – Maggie #3 – Jill #4 – Anthony #5 – Maria #6 – Wanda #7 – Marco #8 – Arnie #9 - Alvin Group # Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 Group 7 Group 8 Group 9 Assigned Patients 1 and 2 Patients 3 and 4 Patients 5 and 6 Patients 7 and 8 Patients 1 and 9 Patients 2 and 3 Patients 4 and 5 Patients 6 and 7 Patients 8 and 9

ELISA: Day 2 Remove wash buffer from both strips Process both strips in the same manner • Add primary antibody; wait 5 minutes • Wash 2 X • Add secondary antibody; wait 5 minutes • Wash 3 X • Add substrate; wait 5 minutes • Analyze results

ELISA Lab Results Patient: Sue Maggie Jill Anthony Maria Wanda Marco Arnie Alvin (+) OR (-) Color match Concentration of to well # antigen in sample

Applications of ELISA Pregnancy Tests http: //www. sumanasinc. com/webcontent/animations/content/pregtest. html other at home diagnostics http: //www. homeaccess. com/