Isolation of the Active Ingredient in an Analgesic Drug

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Sasha Thiel
CH203 Lab
Experiment 1: Isolation of the Active Ingredient in an Analgesic Drug Pre-Lab:
A. Least accurate to most accurate
1. Beakers (5ml markings)
2. 10ml graduated cylinder (0.1 markings)
3. 5ml vials (0.1 and 0.3 markings)
4. 1ml plastic pipets (0.1 ml markings)
5. 1ml syringes (0.1 ml markings)
6. 1ml graduated volumetric pipets (0.01 ml markings)
B. A 1ml graduated volumetric pipet is the best to use if you want 0.15 ml of reactant C. 1ml plastic pipets (used 2 times) are best to use when you want 2 ml of solvent

Safety Hazards:
1. Methanol is flammable and toxic. Don’t breathe it in or drink it. 2. All organic waste goes in the waste containers and not down a sink

Drug| Melting Point|
Acetylsalicylic acid (Aspirin) | 135°-136° C|
Acetaminophen (Tylenol)| 169°-170.5° C|
Ibuprofen (Advil, Motrin) | 75°-77° C|

Acetylsalicylic acid, acetaminophen, and ibuprofen are all active ingredients for pain relievers. However, these pain relievers are not purely composed from one of these three active ingredients. Analgesics (pain-relievers) also contain starch or other inert substances to keep the tablet from falling apart and make them large enough to handle. Also, many of these drugs have coating so that the tablet is easier to swallow and doesn’t taste bitter. In this experiment we will learn microscale level lap techniques such as vacuum filtration, column chromatography, and centrifugation to extract the active ingredient from tablets.

Separation and Purification Scheme:
Analgesic with Binder
Add methanol (CH3OH)
dissolve analgesic
Analgesic in solution with binder
Centrifuge +filtersome binder

Analgesic in solution with binder
Alumina columnremaining binder

Analgesic in solution with methanol
Evaporate most CH3OH (methanol)

Analgesic and some methanol
Remaining CH3OH (methanol)
Ice bath
Analgesic crystal and methanol

Vacuum filtration
Pure analgesic crystal

1. Use one tablet of aspirin, acetaminophen, or ibuprofen. 2. Crush tablet using a mortar and pestle. Makes sure all the tablet’s coating is removed by using forceps. 3. Add crushed tablet, without coating material, into a 3-ml council vial 4. Add 2ml of methanol to the 3-ml conical vial using a glass pipet 5. Cap the vial and shake it thoroughly, making sure the solution is well mixed. Allow for a release in pressure build up by opening the cap. 6. Wait for the larger un-dissolved powder portions have settled in the vial (about 5 minutes) 7. Use a pipet to transfer the remaining liquid into a centrifuge tube 8. Add another 2ml of methanol to the vial and repeat steps 5-7. Add this liquid to the same centrifuge tube. 9. Place the centrifuge tube opposite a tube with the same weight in the centrifuge for 2-3 minutes. Repeat (longer and faster) if supernatant liquid is not clear 10. Transfer supernatant liquid to a test tube with a pipet Column Chromatography

1. Insert a small cotton ball to the bottom of a pipet. Push the cotton down with a stirring rod. 2. Add 0.5 g alumina and tap the pipet to pack
3. Clamp the pipet so that it is vertical above a 5ml conical vial 4. Add 2ml of methanol and allow it to drain until it is equal with the top of the alumina. Make sure to add more methanol to prevent the top of the alumina from running dry. 5. Add the solution from the test tube

6. After the solution has drained, add another 1mL of methanol to the filtration system. Evaporation of Solvent
Note: evaporation must be done in 10-15minutes if handling aspirin 1. Use a pipet to transfer the liquid into small beaker
2. Place the beaker in a 50°C water bath
3. Use a stream of dry air or nitrogen to evaporate faster 4. Evaporate solvent until there is less than 0.5 ml left 5. Remove beaker from bath...
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