R1: 5% w/v Copper Sulphate in water
R2: Benzene: carbon disulphide mixture, 4:1
R3: Strong ammonia
Standard preparation:
1. Weigh 100 mg standard.
2. Dilute to 100 mL with DM water.
3. Take 5 mL of this solution.
4. Dilute to 100 mL with DM water.
Test preparation:
1. Take a sample equivalent to about 100 mg.
2. Dilute to 100 mL with DM water.
3. Take 5 mL of this solution.
4. Dilute to 100 mL with DM water.
Colour development for both standard and test:
1. Take 10 mL of standard/test solution.
2. Add 5 mL R1.
3. Add 2 mL R2.
4. Add 20 mL R3.
5. Shake/extract properly.
6. Read the absorbance of the organic layer at 444 nm.
Pseudoephedrine HCl is a sympathomimetic drug commonly used as a nasal decongestant. It acts by stimulating alpha-adrenergic receptors, causing constriction of blood vessels in the nasal mucosa and reducing swelling, congestion, and mucus production. It is generally used in cold, flu, sinusitis, and allergic rhinitis preparations. Pseudoephedrine HCl is usually administered orally as tablets, capsules, or syrup. In pharmaceutical analysis, it can be estimated by colorimetric or spectrophotometric methods, such as complex formation followed by absorbance measurement. Because it can be misused for illegal synthesis, its sale is regulated in many countries. It should be used carefully.