Robitussin Severe Cough, Cold & Flu Formulation is a complex mixture of organic and inorganic compounds. The main active drug ingredients are acetaminophen, phenylephrine, guaifenesin, and dextromethorphan. Inactive ingredients include anhydrous citric acid, edetate disodium, FD&C red no. 40, glycerin, menthol, natural and artificial flavors, polyethylene glycol, propyl gallate, propylene glycol, purified water, sodium benzoate, sodium citrate, sorbitol solution, sucralose, triacetin, xanthan gum. Acetaminophen or paracetamol is a relatively hydrophilic drug, which is used to treat pain and fever. Phenylephrine is a hydrophilic basic drug, which is primarily used as a decongestant, to dilate the pupil, to increase blood pressure, and to relieve hemorrhoids. Guaifenesin is a hydrophilic organic compound which is used as a drug that is used to help to remove mucus from the mouth due to the common cold and flu. Dextromethorphan is a hydrophobic basic compound, which is used as an over-the-counter cough suppressant. Excipients are hydrophilic and hydrophobic in nature and are added to improve taste and increase stability of the formulation. Several complex methods are required to fully analyze this drug composition. We have developed a simple UV method using Coresep 100 mixed-mode column. Coresep 100 column is a reversed-phase cation-exchange column, based on 2.7 um core-shell articles. It is designed to retain various analytes without the use of ion-pairing reagents. This approach makes these columns fully compatible with mass spec detection. The method for analysis of this drug formulation is reproducible and robust and provides baseline separation of hydrophobic basic, hydrophilic basic, neutral, hydrophobic, and hydrophobic acidic compounds. Hydrophilic acidic compounds might not be retained. The column is compatible with 100% water and 100% ACN and totally resistant to phase collapse, due to polar-embedded ionizable groups on the surface of core-shell particles. Mixed-mode HPLC columns provide 2-D selectivity for the retention of hydrophobic and hydrophilic ionizable compounds.
|Separation Modes:||reversed-phase, cation-exchange|
|Column Dimenstions:||4.6x150 mm, 2.7 um, 90A|
|Mobile Phase:||"A: 10% ACN with 0.03% H2SO4
B: 55% ACN with 0.25% H2SO4
from 100% A to 100% B in 8 min, 4 min hold "
|Flow rate:||1 ml/min|
|Class of compounds:||Amines, Aromatic base, Aromatic compound, Catecholamine, Drug, Neurotransmitter|
|Nature of compounds:||Basic, Hydrophilic, Hydrophobic, Neutral, Polar|
|Compounds:||Acetaminophen, Phenylephrine, Guaifenesin, Dextromethorphan|