Home pregnancy tests determine if human chorionic gonadotropin (hCG) hormone is present in a woman’s urine. If it is present, the individual is pregnant. What type of ELISA test is an at home pregnancy test?

• A. Indirect ELISA.
• B. Sandwich ELISA.
• C. Hormone ELISA.

Answer: (B)

Verified step by step guidance

1. Understand the principle of ELISA (Enzyme-Linked Immunosorbent Assay) tests, which are used to detect the presence of specific antigens or antibodies in a sample.
2. Review the types of ELISA tests: Indirect ELISA detects antibodies, Sandwich ELISA detects antigens by 'sandwiching' them between two antibodies, and Competitive ELISA measures antigen concentration by competition.
3. Recognize that home pregnancy tests detect the hormone human chorionic gonadotropin (hCG), which is an antigen present in urine when a woman is pregnant.
4. Identify that the test uses antibodies specific to hCG to capture and detect the hormone, which fits the Sandwich ELISA format where the antigen (hCG) is 'sandwiched' between two antibodies.
5. Conclude that since the test detects an antigen (hCG) directly using two antibodies, the home pregnancy test is a Sandwich ELISA.