The document discusses enzyme-linked immunosorbent assay (ELISA), a technique used to detect substances like proteins. ELISA uses an enzyme to detect the binding of antibodies to antigens, producing a color change that indicates the presence of the antibody-antigen complex. There are direct and indirect ELISA methods, as well as variations like immobilized antigen ELISA for antibody detection and sandwich ELISA for antigen detection. ELISA has applications in medical diagnostics to detect antibodies in patients and test for substances like allergens in food.

1. Advances in Drug Delivery 23rd of May 2011 ELISA: Enzyme-Linked Immunosorbent Assay Slides by Mathias Bader and Simon Loew

2. ELISA: Enzyme-Linked Immunosorbent Assay 2 ELISA detects substances with antigenic properties (mainly proteins) Based on enzymatic color-reaction Slides by Mathias Bader and Simon Loew

3. Basic principle of ELISA 3 Enzyme is used to detect the binding of Antibody - Antigen Enzyme converts colorless substrate into colored product, indicating the presence of Antibody - Antigen complex ELISA can be used to detect either presence of Antigens or Antibodies Slides by Mathias Bader and Simon Loew

4. Direct and Indirect ELISA 4 Indirect ELISA Direct ELISA Slides by Mathias Bader and Simon Loew

5. 5 Direct ELISA Slides by Mathias Bader and Simon Loew

6. 6 Antibody is adsorbed onto microtiter plate Add serum to test for antigen Specific antigen binds if contained Slides by Mathias Bader and Simon Loew

7. 7 Remove test fluid and unbound antigen Binding of antigen is strong enough to withstand rinsing Slides by Mathias Bader and Simon Loew

8. 8 Remove test fluid and unbound antigen Binding of antigen is strong enough to withstand rinsing Slides by Mathias Bader and Simon Loew

9. 9 Slides by Mathias Bader and Simon Loew

10. 10 Add enzyme labeled antibody Labeled antibody binds to antigens E E E E E E E E Slides by Mathias Bader and Simon Loew

11. 11 Wash sample to remove unbound antibodies E E E E E E E E Slides by Mathias Bader and Simon Loew

12. 12 Wash sample to remove unbound antibodies E E E E E E E E Slides by Mathias Bader and Simon Loew

13. 13 Wash sample to remove unbound antibodies E E E Slides by Mathias Bader and Simon Loew

14. 14 Add substrate Measure color change Positive Negativ E E E Slides by Mathias Bader and Simon Loew

15. Direct and Indirect ELISA 15 Indirect ELISA Direct ELISA Slides by Mathias Bader and Simon Loew

16. 16 Antigen is adsorbed onto microtiter plate Indirect ELISA Add serum to test for antibody Slides by Mathias Bader and Simon Loew

17. 17 Antigen is adsorbed onto microtiter plate Add serum to test for antibody Slides by Mathias Bader and Simon Loew

18. 18 Antigen is adsorbed onto microtiter plate Add serum to test for antibody Wash sample Slides by Mathias Bader and Simon Loew

19. 19 Antigen is adsorbed onto microtiter plate Add serum to test for antibody Wash sample Slides by Mathias Bader and Simon Loew

20. 20 Slides by Mathias Bader and Simon Loew

21. 21 Add secondary antibody E E E E E E E E Primary antibody binds to secondary anitbody Slides by Mathias Bader and Simon Loew

22. 22 Add secondary antibody E E E E E E E E Wash unbound antibodies Slides by Mathias Bader and Simon Loew

23. 23 Add secondary antibody E E E E E E E E Wash unbound antibodies Slides by Mathias Bader and Simon Loew

24. 24 Add secondary antibody E E E Wash unbound antibodies Slides by Mathias Bader and Simon Loew

25. 25 Add substrate Measure color change Positive Negativ E E E Slides by Mathias Bader and Simon Loew

26. Direct vs. Indirect ELISA 26 Advantages of Indirect ELISA: Immunoreactivity of primary antibody is not affected by labeling E E E Wide variety of secondary antibodies available on the market Signal amplification (several epitopes) Advantages of Direct ELISA: Quick methodology – only one AB E E E Cross-reactivity of second AB eliminated Slides by Mathias Bader and Simon Loew

27. Immobilized Antigen vs. Sandwich 27 Immobilized Antigen: Mainly used for antibodydetection E E E Mainly used for antigen detection Sandwich ELISA: E E E Slides by Mathias Bader and Simon Loew

28. Competitive ELISA 28 Step 2: Add antibodys Step 1: Add sample Step 3: Washing Step 4: Add substrate E E E E E E E Quick methodology – just one washing step Slides by Mathias Bader and Simon Loew

29. Applications 29 Medical diagnostic to detect presence of antibodies in patient HIV Test West Nile Virus Detection of potential allergens in food Test kits for eggs and peanuts Drug tests But: high material costs Slides by Mathias Bader and Simon Loew

30. Thankyou 30 Slides by Mathias Bader and Simon Loew