Urine samples and diagnosis

• State what can be tested for in urine

  • Glucose - diagnosis of diabetes
  • Alcohol - in drivers
  • Recreation drugs - random testing in workplace
  • Anabolic steroids - sports
  • HcG- pregnancy testing
• When is HcG triggered

  When embryo binds to uterus lining
• Why do we test for anabolic steroids?

  • Liver damage
  • Can improve performance so considered unfair
  • can test for illegal drugs
  • can test for alcohol
• How can we test for anabolic steroids?

  • Initial sample tested using monoclonal antibodies
  • If this test is positive, second sample ran through mass spectrometry/gas chromatography
• what is the hormone detected in a pregnancy test called?

  hcG
• describe how monoclonal antibodies are made to help in the detection of hCG

  • mouse injected with hCG so it makes the appropriate antibody
  • B-cells that make the required antibody are removed from the spleen of the mouse and fused with a myeloma, a cancer cell which divides rapidly
  • This fused cell is called a hybridoma
  • the hybridomas reproduce rapidly, forming millions of clones making the desired antibody
  • antibodies are collected and purified
• Describe how pregnancy tests work

  • woman passes urine first thing in the morning- highest [hCG] present in urine
  • hCG molecules bind to mobile antibodies with coloured beads forming hCG-mobile antibody complexes. These mobile antibodies are carried up test in urine
  • The hCG-mobile antibody complexes approach the 1st window. They bind to immobilised antibodies with coloured beads that only bind to hCG-mobile antibody complexes to form coloured line if woman is pregnant
  • Excess mobile antibodies travel further up the test to the second window, bind to immobilised antibodies that only bind to the mobile ones not carrying the hCG hormone. This is to ensure the test is working properly and forms coloured line whether the woman is pregnant or not