Advanced Serology

Advanced Serology Immunofluorescence Western Direct Indirect Sandwich Competitive MAC Immunoblotting Northen Southern Sample Washing Conjugate Washing Substrate Stop Sol 1. a) b) c) d) ………………………..is used to detect and amplify an antigen-antibody reaction. Calorimetric biosensor ELISA Potentiometric biosensor Optical biosensor 2. which is working principle of ELISA ? a) Ag-Ab neutralization a) Ag-Ab complex b) A and B c) None of the above 3. ELISA assay………………………. a) Use a secondary radiolabelled antibody b) Require RBC c) Use complement mediated lysis d) Use a secondary enzyme-labelled antibody 4. Which of the following enzymes are used for ELISA ? a) Beta - galactosidase b) Horseradish peroxidase c) Alkaline phosphatase d) All options 5. ELISA detect………………….. a) Antigen b) Antibody c) Both a & b d) None of these 6. ELISA is so sensitive because ofa) specificity of antigen - antibody binding b) sensitivity of enzyme c) both a and b d) none of these 7. Please arrange the following steps about ELIZA (Enzyme-linked immunosorbent assay) in chronological order i. incubate with antibody-enzyme complex that binds primary antibody ii. Add stop solution & take reading. iii. add substrate, formation of coloured product. iv. incubate with primary antibody against specific antigen a) i, iv, ii, iii b) i, iv, iii, ii c) ii, iv, iii, i d) ii, iv, i, iil 8. What is the role of goat anti-rabbit IgG horseradish peroxidase conjugate in the experiment? a) Antigen b) Primary antibody c) Second antibody d) Substrate 9. In order to stop the reaction between enzyme and substrate, what process is needed? a) Incubate the sample at 100°C b) Add strong acid to sample c) Wash sample with PBS-Tween d) Add blocking solution to sample 10. What does the acronym "ELISA" stand for? a) Enzyme-Linked Immunosorbent Assay b) Enzyme-Linked Immunostatic Assay c) Electro-Luminescent Immunoassay d) Efficient Luminescence and Immunostasis 11. What is the purpose of the "blocking" step in an ELISA? a) To promote the binding of antigens b) To prevent nonspecific binding of antibodies c) To inhibit the activity of enzymes d) To enhance the sensitivity of the assay 12. In a competitive ELISA, what competes with the sample antibody for binding to the antibody? a) A blocking agent b) A substrate c) Another antibody d) labeled antibody 13. What is the purpose of the wash step in ELISA? a) To dilute the sample b) To remove unbound molecules c) To label the antigen d) To add more enzymes to the reaction 14. Which color change is typically observed when the enzyme substrate reacts in a positive ELISA result? a) From colorless to yellow b) From colorless to blue c) From yellow to colorless d) From green to red 15. Which type of ELISA is commonly used to measure the concentration of specific proteins, such as cytokines or hormones, in a sample? a) Indirect ELISA b) Direct ELISA c) Competitive ELISA d) Sandwich ELISA 16. Which of the following is NOT a common application of ELISA? a) Diagnosis of infectious diseases b) Monitoring of autoimmune diseases c) Allergy testing d) DNA sequencing 17. What does a high optical density (OD) value in an ELISA result indicate? a) A low concentration of the target molecule b) A negative result c) An error in the assay d) A positive result or a high concentration of the target molecule 18. What does a high optical density (OD) value in a competitive ELISA result indicate? a) A low concentration of the target molecule b) A negative result c) An error in the assay d) A positive result or a high concentration of the target molecule RIA 1. a) b) c) d) What is the primary purpose of Radioimmunoassay (RIA)? Detection of antibodies in blood samples Visualization of cells using radioisotopes Quantification of radioactive isotopes Measurement of specific antigens or hormones 2. In RIA, what component is labeled with a radioactive isotope for detection? a) Antibodies b) Substrates c) Antigens d) Enzymes 3. Which radioactive isotope is commonly used in RIA? a) Hydrogen-3 (tritium) b) Iodin 125 c) Carbon-14 d) Uranium-238 4. What type of binding does competitive RIA measure? a) Antibody-antigen interaction b) Radioisotope interactions c) Antibody-antigen binding inhibition d) Antigen-antibody complex formation 5. What is the main advantage of using RIA over other immunoassays, such as ELISA? a) RIA is faster. b) RIA does not require a standard curve. c) RIA requires smaller sample volumes. d) RIA is highly sensitive and can detect low concentrations of antigens. 6. What is the primary application of RIA in the field of medicine? a) Measuring RNA concentration b) Detecting gene mutations c) Determining blood type d) Quantifying hormone levels and diagnosing diseases CLIA/ ECLIA ECLIA: ElectroChemiLuminescence ImmunoAssay CLIA: ChemiLuminescence ImmunoAssay ❑ Much more sensitive & specific as compared to ELISA ❑ CLIA Detection limit: 10−18 moles ❑ ECLIA Detection limit: 10−21 moles Luminol HRP 𝐻2 𝑂2 Ground state Excited state Excited state Ground state Light Reagents Ruthenium Streptavidin Biotin Magnetic beads Tripropylamine(TPA) (Added streptavidin coated magnetic beads) ELECTRODE Excited state ELECTRODE ELECTRODE ELECTRODE Ground state ELECTRODE ELECTRODE ELECTRODE 1. a) b) c) d) What is the primary detection method used in ECLIA? Absorbance Fluorescence Electrochemiluminescence Radioactivity 2. Which of the following is a key characteristic of ECLIA compared to other immunoassay techniques? a) High sensitivity and broad dynamic range b) Low background signal and high throughput c) Simplicity and low cost d) High efficiency and minimal sample preparation 3. What is the purpose of the electrochemical reaction in ECLIA? a) To create an electrochemical signal b) To generate a fluorescent signal c) To initiate a chemical reaction d) To detect an analyte 4. Which of the following element is used in ECLIA ? a) Uranium b) Lead c) Ruthenium d) Iodin South ka Dosa, North ki Roti, West ka Pizza B lotting Tec hnique Northern Blot RNA Southern Blot DNA Dosa- DNA Western Blot Protein Roti- RNA Pizza- Protein Mnemonic Note No: 6 © Kaushik Sen 1. a) b) c) d) What is the primary purpose of Western blotting? Gene expression analysis Protein detection and analysis DNA amplification RNA quantification 2. Which type of molecules is separated by size in a Western blot? a) Carbohydrates b) Antibodies c) Proteins d) Nucleotides 3. Which blotting technique is used for DNA molecules, as opposed to proteins? a) Western blotting b) Southern blotting c) Northern blotting d) Eastern blotting 4. What is the purpose of the blotting step in Western blotting? a) To increase protein size b) To digest proteins c) To transfer proteins from the gel to the membrane d) To amplify proteins