Aspirin

Applications:

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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.

Condition

Column	Primesep 100, 3.2x150 mm, 5 µm, 100A
Mobile Phase	MeCN/H2O
Buffer	TFA
Flow Rate	0.5 ml/min
Detection	UV, 210 nm

 

Description

Class of Compounds	Acid, Hydrophilic, Ionizable
Analyzing Compounds	Benzoic acid, Acetaminophen, Caffeine, Aspirin

 

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Acetylsalicylic Acid
Aspirin
Benzoic Acid
Caffeine

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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

Condition

Column	Legacy L1, 4.6x150 mm, 5 µm, 100A
Mobile Phase	MeOH/H2O/AcOH 28/69/3
Buffer	AcOH
Flow Rate	1.0 ml/min
Detection	UV, 270 nm

 

Description

Class of Compounds	Drug, Acid, Hydrophobic, Ionizable
Analyzing Compounds	Acetaminophen, Caffeine, Aspirin, Benzoic acid, Salicylic acid

 

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Acetaminophen (Paracetamol)
Aspirin
Benzoic Acid
Caffeine

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USP Methods for the Analysis of Aspirin (Acetylsalicylic acid (ASA)) Using Legacy L1 Column

  Application Notes: Aspirin is one of the oldest analgesics. While it is one of the oldests analgesics, it is still widely used today, and is still one of the most common drugs. According to the USP methods, aspirin contains not less than 99.5% and no more than 100.5 percent of aspirin calculate on a dried basis. The USP HPLC method for the separation of aspirin 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: Aspirin and salicylic acid Mobile phase: 20 mM AmFm pH 3.0/MeCN- 75/25 Detection technique: UV Reference: USP35: NF30

Condition

Column	Legacy L1, 4.6x300 mm, 5 µm, 100A
Mobile Phase	MeCN - 25%
Buffer	AmFm pH 3.0 20 mM -  75%
Flow Rate	1.0 ml/min
Detection	UV, 250 nm

 

Description

Class of Compounds	Drug, Acid, Hydrophobic, Ionizable
Analyzing Compounds	Aspirin (Acetylsalicylic acid (ASA))

 

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Acetylsalicylic Acid
Aspirin

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