| CAS Number | 65-85-0 |
|---|---|
| Molecular Formula | C7H6O2 |
| Molecular Weight | 122.124 g/mol |
| InChI Key | WPYMKLBDIGXBTP-UHFFFAOYSA-N |
| LogP | 1.87 |
| Synonyms |
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Applications:
Hydrophobic and Hydrophilic Compound Separation
Primesep 100 separates a mixture of polar and nonpolar compounds in one analytical run. The amino acid cysteine; amino acid derivatives L-cystine, 2,2-dimethylcystine, and 2-methylcysteine; the polar acid benzoic acid; and the nonpolar neutral toluene are separated by a gradient using a combination of polar and hydrophobic interactions. The separation method uses a mobile phase mixture of water, acetonitrile (MeCN, ACN) and sulfuric acid (H2SO4) with UV detection at 210 nm.
Application Analytes:
2,2-Dimethylcysteine
2-Methylcysteine
Amino Acids
Benzoic Acid
Cysteine
L-Cystine
Toluene
Complex Mixture of Acids, Bases, Amino Acids, and Neutral Compounds
Primesep 100 separates a mixture of amino acids (tyrosine, phenylalanine), organic acids (benzoic acid, mandelic acid), amines (benzylamine, pyridine), and neutrals (benzonitrile, toluene) in one HPLC run by combining reversed-phase, cation-exchange, and polar interactions. The method is tunable and peak order can be changed significantly by adjusting acetonitrile and trifluoroacetic acid concentrations. The separation method uses a mobile phase mixture of water, acetonitrile (MeCN, ACN) and trifluoracetic acid (TFA) and compatible with UV, mass spec (LC/MS) and evaporative light scattering (ELSD) detection.
Application Analytes:
Amino Acids
Benzoic Acid
Benzonitrile
Benzylamine
Mandelic Acid
Organic Acids
Phenylalanine
Pyridine
Toluene
Tyrosine
Separation of Diacid Hydrophobic and Ion Exchange Modes
Primesep B combines a hydrophobic, reversed-phase mechanism with ion exchange to separate the diacids, fumaric, benzoic, phthalic, naphthoic, and maleic acids. Changing the acetonitrile content of the mobile phase reverses the peak order for naphthoic and maleic acids. Primesep B combines reversed-phase and anion-exchange mechanism with a mobile phase of water, acetonitrile (MeCN, ACN) and trifluoracetic acid (TFA) and UV detection at 250 nm.
Application Analytes:
Benzoic Acid
Dicarboxylic Acids
Fumaric Acid
Maleic Acid
Naphthoic Acid
Phthalic Acid
Acid Effect on Retention of Acidic Analytes
In mixed-mode chromatography, retention time and elution order can be changed for acidic analytes based on the pH of the mobile phase. In this application, the order of elution for benzoic acid and benzonitrile is changed by changing the pH of the mobile phase. At lower pH (pH-2, TFA), ionization of carboxylic acid fragment of benzoic acid is totally suppressed (not ionized), and benzoic acid does not show any anion-exchange properties. As the pH of the mobile phase increases (pH 4, formic acid), the carboxylic acid fragment of benzoic acid is ionized and participates in ion-exchange interaction with positively charged sites of the mixed-mode column. In most cases, changing pH does not change retention of neutral analytes. Mixed-mode chromatography is compatible with all detection techniques (UV, ELSD, CAD, LC/MS, etc.)
Application Analytes:
Benzoic Acid
Benzonitrile
HPLC Separation of Carboxylic Acids
HPLC separation of carboxylic acids (nicotinic acid, benzoic acid and acetylbenzoic acid) on Primesep B2 column using an isocratic method by reverse-phase and anion-exchange mechanisms. The elution of carboxylic acids using the same isocratic method and mobile phase can be reversed by using a reverse-phase cation-exchange mechanisms of the Primesep 100 column. The mobile phase is water, acetonitrile (MeCN, ACN) and formic acid with a UV detector.
Application Analytes:
Acetylbenzoic Acid
Benzoic Acid
Nicotinic Acid
HPLC Separation of Active Compounds in Drug Formulation
An HPLC method for the separation of active drug compounds on a Primesep 200 column. The retention of compounds is achieved through reverse-phase, cation exchange and hydrophobic interactions. Benzoic acid, hyoscyamine sulfate and phenyl salicylate are baseline separated using simple mobile phases of water, acetonitrile (MeCN, ACN) and trifluoroacetic acid (TFA) with a UV detector.
Application Analytes:
Benzoic Acid
Hyoscyamine Sulfate
Phenylsalicylate
HPLC Separation of Acidic, Basic and Zwitterionic Compounds on Special Columns for Retention of Polar Compounds
Primesep mixed-mode columns are designed to separate basic, acidic, neutral and zwitter-ionic compounds. Elution of these compounds is facilitated by acetonitrile and ions in the mobile phase. In all cases the retention time on mixed-mode columns is significantly longer than on traditional reverse-phase columns. Presence of cation-exchange mechanism in Primesep 100 column allows to achieve better retention and peak shape for analytes like phenylalanine and benzylamine. Various buffers can be used along with different detection techniques. This HPLC method can be adopted as a universal approach for analysis of basic, acidic and zwitter-ionic compounds in complex mixtures and formulations. Compounds can be monitored by UV, ELSD, CAD and LC/MS.
Application Analytes:
Benzoic Acid
Benzylamine
Phenylalanine
Zwitterion
HPLC Analysis of Polar Basic and Acetic Compounds on Primesep AB Column
Mixture of polar acidic and basic compounds is separated on a Primesep AB mixed-mode HPLC column. Dopamine and tyrosine are retained by combination of reversed-phase and cation-exchange mechanisms. Maleic acid is retained by anion-exchange mechanism, and benzoic acid is retained by reversed-phase mechanism. Primesep AB is a trimodal column with a C12 hydrophobic chain and cation-exchange and anion exchange groups on the surface. Method utilizes UV detection but can be used with other detection techniques (ELSD, LC/MS, Corona).
Application Analytes:
Benzoic Acid
Dopamine
Maleic Acid
Tyrosine
HPLC Application for Simultaneous Separation of Amino Acids, Hydrophilic Acidic and Hydrophobic Neutral Compounds
Mixed-mode chromatography allows separating, in single run, compounds with vastly different properties. A method for separation of amino acids (cysteine, methylcysteine, cystine and dimethylcysteine) in the presence of carboxylic acid (benzoic) and hydrophobic neutral compounds was developed on Primesep 100 mixed-mode column. At lower pH ionization of carboxylic acids is suppressed. Amino acids are retained as basic compound based on reverse phase and cation exchange mechanisms. Carboxylic acids are retained on this column based on weak reverse phase mechanisms. Neutral compounds are retained by reverse phase mechanism as on any other column. Retention time of basic, zwitter-ionic and hydrophobic compound can be adjusted by manipulation of mobile phase composition. ELSD, UV or LC/MS detection can be used based on the properties of analytes and mobile phase selection.
Application Analytes:
2,2-Dimethylcysteine
2-Methylcysteine
Benzoic Acid
Cystine
L-Cysteine
Toluene
HPLC Separation of 8 Generic Compounds on Primesep Columns
Mixed-mode HPLC columns allow to analyze compounds with drastically different properties in one run. Acidic, basic, and neutral compounds can be separated in one run using either isocratic or gradient conditions. In this application, neutral hydrophilic (uracil, phenol and hydroquinone), neutral hydrophobic (toluene), hydrophilic acidic (benzoic acid), hydrophilic basic (lutidine) and hydrophobic basic (amitriptyline) are separated using gradient of ACN. Neutral compounds are retained by reversed-phase mechanism, hydrophilic acidic compound become more hydrophobic at lower pH and retain by reversed-phase mechanism too. Basic compounds are retained by cation exchange mechanism, and hydrophobic basic compounds are retained by reversed-phase and cation-exchange mechanisms. All compounds are resolved within 17 minutes on a short column. Method can be applied to various polar and hydrophobic compounds, which can be separated on one column and in one run. Mixed-mode columns can operate in single or combination of several modes: reversed-phase, ion-exchange, ion-exclusion and HILIC. This mixed-mode HPLC column can be used as a general column for separation of wide range of compounds.Application Analytes:
Amitriptyline
Benzoic Acid
Benzylamine
Hydroquinone
Lutidine
Phenol
Toluene
Uracil
HPLC Separation of Parabens and Benzoic Acid
Parabens possess antibacterial and antifungal properties and are therefore widely used in pharmaceutical and cosmetic industries as preservatives in products. Parabens and benzoic acid can be baseline separated in a short time frame using Primesep B2 reverse-phase HPLC column with a simple mobile phase of water, acetonitrile (ACN, MeCN) and phosphoric acid of 0.1% as buffer. UV detection at 210nm.
Application Analytes:
Benzoic Acid
Methylparaben
Parabens
Propylparaben
HPLC Separation of Acidic, Basic, and Neutral Compounds
Primesep 100 and Primesep 200 columns can be used as a universal column for analysis of wide range of compounds. These mixed-mode reversed-phase ion-exchange HPLC columns can provide a valuable alternative to traditional reversed-phase column. Amines, amino acids, quaternary amines, and various zwitter-ions can be analyzed along with hydrophobic compounds and organic and inorganic counter-ions. In this application, 8 compounds with different hydrophobic, hydrophilic, basic and acidic properties are separated based on their properties. Primesep 100 column is a mixed-mode HPLC column with a C12 carbon chain and carboxylic acid on the surface with pKa of 1. Primesep 200 column is a mixed-mode HPLC column with a C12 carbon chain and carboxylic acid on the surface with pKa of 2. These columns can be used with 100% organic (ACN) and 100% aqueous mobile phases. This HPLC method can be adopted as a generic and robust approach for analysis of acidic, basic and neutral compounds within the same run.
Application Analytes:
Amitriptyline
Benzoic Acid
Benzylamine
Hydroquinone
Lutidine
Phenol
Toluene
Uracil
HPLC Separation of Organics Acids
Primesep D separates organic acids such as fumaric, benzoic, phthalic, naphthoic, and maleic acids by a mixture of anion exchange and reversed phase. Retention times and elution order can be changed by adjusting the percentage of acetonitrile in the mobile. This can not be done by traditional ion-exchange and ion-exclusion chromatography. The HPLC separation uses a mobile phase of water, acetonitrile (MeCN, ACN) and trifluoroacetic acid (TFA) and UV detection at 250 nm.
Application Analytes:
Benzoic Acid
Fumaric Acid
Maleic Acid
Naphthoic Acid
Organic Acids
Phthalic Acid
Effect of mobile phase composition on retention of 3 compounds on Obelisc R
This application shows the effect of mobile phase composition on retention of acidic, basic and neutral compound. Retention of basic and acidic compounds is controlled by buffer pH and concentration, while retention of neutral compound is controlled by the amount of acetonitrile. Buffer pH changes not only ionization state of ionizable basic and acidic compounds, but ionization state of trimodal stationary phase Obelisc R. Available detection techniques include UV, ELSD, LC/MS, and Corona.
Application Analytes:
Benzoic Acid
Benzonitrile
Benzylamine
HPLC Separation of Amino Acids, Bases, Acids, and Neutrals on Obelisc R
| Column | Obelisc R, 4.6x250 mm, 5 µm, 100A |
| Mobile Phase | MeCN/H2O - 35/65% |
| Buffer | AmAc 10 mM pH 4.0 |
| Flow Rate | 1.0 ml/min |
| Detection | UV, 250 nm |
| Class of Compounds | Drug, Acid, Bases, Neutral, Hydrophilic, Ionizable, Vitamin, Supplements, Amino acid |
| Analyzing Compounds | Amino acids |
Application Analytes:
2,6-Lutidine
Benzoic Acid
Benzonitrile
Benzylamine
Phenol
Phenylalanine
Pyridine
Toluene
Tryptophan
HPLC Separation of Guanidine and Benzoic Acids on Primesep 100 Column
Application Analytes:
Benzoic Acid
Dinitrophenylacetic Acid
Guanidine
Separation of Alginic Acid and Related Products
Alginate is used in various pharmaceutical preparations. Chemically, it is a linear copolymer with homopolymeric blocks of (1-4)-linked ?-D-mannuronate (M) and its C-5 epimer ?-L-guluronate (G) residues, respectively, covalently linked together in different sequences or blocks. Alginic acid can be separated from benzoate, citric acid and saccharin by mixed-mode chromatography on Primesep C HPLC column. This method can be used to quantitate alginic acid, citric acid or saccharin in complex mixtures. Various detection technique can be used (UV, ELSD, LC/MS), based on mobile phase selection.
Application Analytes:
Alginic Acid
Benzoic Acid
Citric Acid
Saccharin
HILIC Separation of Aromatic Acids
Obelisc N column are used for separation of weak and strong organic acids in mixed-mode HILIC. Benzoic and naphthalenesulfonic acids are retained based on polar interaction mode and anion-exchange mode. Order of elution and retention pattern can be changed by modifying mobile phase. PH of the mobile phase changes ionization state of stationary phase and analytes. Fast quantitation method for benzoic and naphthalenesulfonic acid can be developed using UV, ELSD or LC/MS detection. HPLC Method can be used for mixture of organic and inorganic strong and weak acids.
Application Analytes:
Benzoic Acid
Naphthalenesulfonic Acid
Organic Acids
HPLC Separation of Components of Excedrin
Excedrin is over-the-counter pain reliever containing acetaminophen, caffeine and aspirin as active ingredients of this drug composition. Acetaminophen (paracetamol) is used as analgesic and pain reliever. It is a neutral compound with low hydrophobicity. Aspirin or acetylsalicylic acid is used as analgesic and anti-inflammatory component of many OTC compositions. It is weakly acidic and slightly hydrophobic compound. Caffeine is xanthine alkaloid which is psychoactive stimulant drug. All four compounds are separated on mixed-mode Primesep 100 HPLC column with acetonitrile/water/TFA mobile phase. In this HPLC application compounds are retained by reversed phase mechanism. This HPLC method is short and robust.
Application Analytes:
Acetylsalicylic Acid
Aspirin
Benzoic Acid
Caffeine
USP Methods for the Analysis of Guaifenesin Using a Legacy L1 Column
Application Notes: Guaifenesin is common, over the counter expectorant. Guaifenesin contain no less than 98 percent and not more than 102 percent of the labeled amount of guaifenesin calculated on a dried basis, according to the USP methods. the The USP HPLC method for the analysis of guaifenesin was developed on our Legacy L1 column according to the US Pharmacopeia methodology. L1 classification is assigned to reversed-phase HPLC column containing C18 ligand. Support for the material is spherical silica gel with particles size 3-10 um and pore size of 100-120A.
Application Columns: Legacy L1 C18 HPLC column
Application compounds: Guaifenesin, benzoic acid
Mobile phase: MeOH/H2O/AcOH 40:60:1.5
Detection technique: UV
Reference: USP 35- NF30
Application Analytes:
Benzoic Acid
Guaifenesin
USP Methods for the Analysis of an Analgesic Mixture Using the Legacy L1 Column
Application Notes: Acetametaphin, aspirin, and caffeine tablets contain not less than 90 percent and not more than 110 percent of the labeled amounts if acetametaphin, asprin, and caffeine according the USP methods. USP HPLC method for separation of acetaminophen, aspirin and caffeine was developed on Legacy L1 column according to US Pharmacopeia methodology. L1 classification is assigned to reversed-phase HPLC column contains C18 ligands. Support for the material is a spherical silica gel with particles size 3-10 um and pore size of 100-120A. Resolution between critical pairs corresponds to rules and specifications of USP.
Application Columns: Legacy L1 C18 HPLC column
Application compounds: Acetaminophen, Aspirin, Caffeine, benzoic acid, and salicylic acid
Mobile phase: MeOH/H2O/AcOH 28/69/3
Detection technique: UV
Reference: USP30: NF35
Application Analytes:
Acetaminophen (Paracetamol)
Aspirin
Benzoic Acid
Caffeine
USP Analysis of Dopamine Using a Legacy L1 column
Application Notes: Dopamine is a naturally occurring neurotransmitter found in the brain. Dopamine is a well studied compound because dopamine is an important neurotransmitter known to regulate many functions from pain response to behavior disorders. According to USP methods, dopamine hydrochloride contains not less than 98% and not more than 102% dopamine hydrochloride calculated on the dried basis. The USP HPLC method for the separation of hydrocortisone was developed on Legacy L1 column according to the US Pharmacopeia methodology. L1 classification is assigned to reversed-phase HPLC column containing C18 ligand. Support for the material is spherical silica gel with particles size 3-10 um and pore size of 100-120A. Resolution between critical pairs corresponds to rules and specifications of USP.
Application Columns: Legacy L1 C18 HPLC column
Application compounds: Dopamine hydrochloride
Mobile phase: Water with 1% acetic and 5mM octanesulfonic acid/MeCN
Detection technique: UV
Reference: USP35: NF30
Application Analytes:
Benzoic Acid
Dopamine
Separation of Phthalic Acids and Related Impurities
Phthalic acid, phthalic acid isomers, and related products present in the production of phthalic acid were separated on the Primesep D column, based on reversed-phase and in-exchange mechanisms. Neutral, hydrophobic compounds of the phthalic acid production are retained by a reversed-phase mechanism, and phthalic acid and other acidic compounds are retained by a combination of reversed-phase and anion-exchange mechanisms. Resolution and selectivity of this separation can be modified by varying the amount of acetonitrile, buffer concentrations, and buffer pH. This method can be used for monitoring the production cycle of phthalic acid and related impurities.
| Column | Primesep D, 4.6x150 mm, 5 µm, 100A |
| Mobile Phase | Gradient MeCN - 10-50%, 15 min |
| Buffer | H2SO4 - 0.1% |
| Flow Rate | 1.0 ml/min |
| Detection | UV, 210 nm |
| Class of Compounds | Acid, Hydrophilic, Ionizable |
| Analyzing Compounds | Terephthalaldehyde, Phthalic acid, 4-Carboxybenzaldehyde, Benzoic acid, Terephthalic acid, p –Tolualdehyde, p-Toluic acid |
Application Analytes:
4-Carboxybenzaldehyde
Benzoic Acid
Phthalic Acid
Terephthalaldehyde
Terephthalic Acid
p-Tolualdehyde
p-Toluic Acid
Separation of Benzoic and Acetylbenzoic acid in Hydrogen-Bonding Mode
A general approach for analysis of various organic acids with MS detection in negative mode was developed using hydrogen-bonding stationary phase - SHARC 1. A highly sensitive method allows to analyze traces of organic acids in various matrices using ACN/MeOH/ammonia mobile phase. In hydrogen-bonding chromatography acetonitrile is a weaker solvent and alcohol is a stronger solvent. Various gradient and isocratic conditions can be used
| Column | Sharc 1, 3.2x100 mm, 5 µm, 100A |
| Mobile Phase | MeCN/MeOH - 95/5% |
| Buffer | Ammonia 10mM |
| Flow Rate | 005 ml/min |
| Detection | UV, 250 nm |
| Class of Compounds | Acid, Hydrophilic, Ionizable, Vitamin, Supplements |
| Analyzing Compounds | Benzoic Acid, Acetylbenzoic acid |
Application Analytes:
4-Acetylbenzoic Acid
Benzoic Acid
HPLC Separation of Caffeine, Benzoic acid and Acetaminophen
| Column | Legacy L1, 4.6x250 mm, 5 µm, 100A |
| Mobile Phase | MeOH - 28% |
| Buffer | Acetic Acid - 3% |
| Flow Rate | 1.5 ml/min |
| Detection | UV, 275 nm |
| Class of Compounds | Drug, Acid, Hydrophilic, Hydrophobic, Ionizable |
| Analyzing Compounds | Caffeine, Benzoic acid, Acetaminophen |
Application Analytes:
Acetaminophen (Paracetamol)
Benzoic Acid
Caffeine
Generic Screening Method for Complex Mixtures
Application Analytes:
2,3-Dihydroxybenzoic Acid
2,6-Lutidine
Amitriptyline
Benzoic Acid
Benzylamine
DOPA (3,4-dihydroxy-L-phenylalanine)
Epinephrine
Ethyl Paraben
Homovanillic Acid
Hydroxytryptophan
Methylparaben
Phenol
Toluene
Tryptophan
Uracil