Separation of NyQuil Active Ingredients on Primesep C
Primesep C separates the active ingredients in the over-the-counter cold medicine, NyQuil. Succinate and bromate co-elute early, but acetaminophen, pseudoephedrine, doxylamine, and dextromethorphan are baseline resolved. A combination of cation exchange, complex formation, and hydrophobic interactions separate this mixture with a mobile phase of water, acetonitrile (MeCN, ACN) and triethylamine (TEA) phosphate with UV detection at 205 nm.
NyQuil is a cough medication produced by Procter&Gamble. It consists of acetaminophen, pseudoephedrine, doxylamine and dextromethorphan. Most of the analytical HPLC methods include either use of ion-pairing reagent or a gradient elution. Mixed-mode chromatography allows to replace long gradient method with short isocratic method. All four compounds are well separated within 3-5 minutes. Methods can be optimized for analysis of other cough composition containing general cough suppressants and pain killers. Method is robust and being validated at several drug companies.
Mixed-mode chromatography allows to separate various hydrophobic and hydrophilic drugs in one HPLC method. Presence of at least two mechanism of retention allows adjust selectivity of separation by changing three parameters: amount of acetonitrile, buffer concentration and buffer pH. Seven common drugs are separated on a Primesep C trimodal HPLC column in gradient method. Method provides alternative selectivity to traditional reversed-phase chromatography. Operational range in which basic compounds are retained the most is from pH 3 to 5. At higher pH, longer retention can be achieved. Mixed-mode chromatography provides longer retention and better peak shapes for basic and acidic analytes. Method can be used in analysis of drugs and pharmaceuticals.
Comparison of the Separation of Polar Drugs on Obelisc R and Zorbax SB-AQ
Common hydrophobic basic and hydrophilic basic drugs are separated by mixed-mode chromatography with greater selectivity and resolution than traditional reversed-phase column. Drugs are retained by combination of reversed-phase and cation-exchange mechanisms. Retention time is controlled by amount of acetonitrile, buffer concentration and buffer pH. Available detection techniques are based on buffer selection and include UV, Evaporative Light-Scattering Detector (ELSD), Corona (CAD), LC/MS, etc. This HPLC method can be adopted as general approach for analysis of drugs and pharmaceuticals.
HPLC Analysis of Pseudoephedrine and Citric Acid on Primesep Column
Pseudoephedrine is a drug used in cough and cold compositions. One of the preservatives in solutions of pseudoephedrine is citric acid. Both compounds are hydrophilic in nature, with pseudoephedrine being a basic compound and citric acid an acidic compound. Separation of these two compounds is achieved on a Primesep N column. Compounds are separated by combination of HILIC, cation-exchange and anion-exclusion mechanisms. Pseudoephedrine and citric acid are monitored by UV. This HPLC method can be adopted as generic approach for analysis of pseudoephedrine and other hydrophilic drugs and preservatives in mixtures.
HPLC Separation of Drugs in Tylenol Cold and Cough Remedies
Components of Tylenol Cold and Cough Remedy are separated on Obelisc R mixed-mode column. Method can be used to determine compounds in various cough and cold compositions. Neutral (acetaminophen), basic (chlorpheniramine, dextromethorphan and pseudoephedrine) and acidic (maleic acid/Maleate) components are analyzed with perfect peak shape and retention control. Method can be used in production, QC/QA and biological studies for quantitation of various components in pharmaceutical formulations (Advil, Tylenol, Dimetapp, Robitussin, NyQuil, etc)
HPLC Separation of Drugs in Advil Allergy and Sinus
Ibuprofen is in a group of drugs called non-steroidal anti-inflammatory drugs (NSAIDs). Ibuprofen works by reducing hormones that cause inflammation and pain in the body. Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose). The combination of chlorpheniramine, ibuprofen, and pseudoephedrine is used to treat sneezing, itching, watery eyes, runny nose, stuffy nose, sinus congestion, cough, and pain or fever caused by the common cold or flu in common over-the-counter medication (Advil, NyQuil, Tylenol, etc.) Active ingredients of Advil Allergy and Sinus composition are separated by combination of reverse phase, cation-exchange and anion exchange mechanisms. Obelisc R mixed-mode column is used to separate pseudoephedrine (polar basic compound), chlorpheniramine (hydrophobic basic compound), ibuprofen (hydrophobic acidic compound) and maleic acid (counter-ion, hydrophilic acid compound). Method can be used for QC in production, impurity profiling and research and development. All compounds are well separated with high efficiency and good peak shape. Method uses ammonium formate buffer but other buffers can be used as well (ammonium acetate, sodium and ammonium phosphate) with corresponding detection technique - ELSD, LC/MS, and UV. Chlorpheniramine is an antihistamine that reduces the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.
Motrin is cough and cold composition manufactured by McNeil PPC. It contains ibuprofen as non-steroidal anti-inflammatory drug (N-SAID) and pseudoephedrine as decongestant. Ibuprofen is hydrophobic acidic molecule and pseudoephedrine hydrophilic molecule. Pseudoephedrine does not retained well in reversed phase chromatography and requires the use of ion-pairing reagent. In the absence of ion-pairing reagent pseudoephedrine comes close to the void of the column even at low concentrations of acetonitrile, while ibuprofen shows strong retention by reversed-phase mechanism. Different properties of these two molecules require gradient elution and consequent equilibration of the column. In contrast when mixed-mode HPLC column, like Primesep 100, is used, the method can be isocratic, very short with no equilibration of the column. Ibuprofen is retained by strong reversed-phase mechanism and pseudoephedrine is retained by weak reversed-phase and strong cation-exchange mechanisms on Primesep 100 column. Retention time of hydrophobic molecule is controlled by amount of acetonitrile, and retention of hydrophilic basic molecule is controlled by the amount of buffer and buffer pH. Method can be UV, ELSD and LC/MS compatible with various additives to the mobile phase (TFA, ammonium formate or acetate, sulphate or phosphate buffers at various pH). This mixed-mode column can be used for analysis of other OTC drugs including mixtures of basic, acidic and hydrophobic compounds.
HPLC Separation of Pseudoephedrine, Norephedrine, Phenylephrine, and Norphenylephrine Using Hydrogen Bonding Mode
Application Notes: Neurotransmitters are polar basic compounds. Several HPLC techniques are used to analyze these hydrophilic molecules. The most common techniques are reversed-phase with ion-pairing reagents chromatography, ion chromatography, HILIC, and mixed-mode chromatography. SIELC developed a new approach of analysis, which is based on hydrogen bond interactions. Hydrogen-bonding offers unique and alternative selectivity to traditional approaches like reversed-phase, HILIC, ion-exchange, and mixed-mode chromatography. Our methods are fully compatible with ELSD, LC/MS and prep chromatography.
Application Columns: SHARC 1, 3.2x100 mm, 5 um, 100A. To learn more about SHARC 1 columns click here. To order this column click here. To see more chromatographic separations check our web site.
Application compounds: Pseudoephedrine, norephedrine, phenylephrine and norphenylephrine