Testing Urine Samples

Question 1

What happens when a human embryo is implanted in the uterine lining?

Answer 1

starts secreting pregnancy hormone: human chorionic gonadotrophin (hCG), relatively small glycoprotein, mol mass = 36700, can be in urine 6 days after conception

Question 2

How do current pregnancy tests work?

Answer 2

monoclonal antibodies, only bind to hCG, strip soaked in urine, any hCG attaches to antibody that is tagged with blue bead, one blue line for comparison, 2nd = pregnant

Question 3

What are anabolic steroids?

Answer 3

increase protein synthesis within cells, drugs that mimic action of steroid hormones that increase muscle growth

Question 4

What is controversial about anabolic steroid use?

Answer 4

non medical use can give advantage in competitive sports: banned by all major sporting bodies, dangerous side effects

Question 5

What is the half life of anabolic steroids? How large are they?

Answer 5

half life: 16h, remain in blood for many days, relatively small so enter nephron easily

Question 6

What does testing for anabolic steroid involve?

Answer 6

analysing urine sample in lab with gas chromatography or mass spectrometry

Question 7

What happens in gas chromatography?

Answer 7

sample vaporised in presence of gaseous solvent and passed down tube lined by absorption agent, each substance dissolves differently in gas and stays for unique amount of time: retention time

Question 8

What does the analysis of gas chromatography produce?

Answer 8

substance comes out of tube and absorbed on lining, chromatogram, standard samples of drugs and urine samples are run so drugs can be identified, quantified