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Amino Acids Testing

Amino Acids Testing At NJ Labs

Common Amino Acids Image
Branched chain amino acids Image

Amino acids can be tested for potency and impurities utilizing various types of methods. NJ Labs has been testing amino acids for many industries including pharmaceuticals, biologics, and supplements and for many years utilizing compendial methods where parts of United States Pharmacopeia (USP), European Pharmacopeia (EP) and Japanese Pharmacopeia (JP) have been harmonized. The following are a list of amino acids for which we commonly test. If you are looking for an amino acid to be tested that is not listed here, please contact us by using the contact form below:

  • L-Arginine
  • L-Arginine Hydrochloride
  • L-Histidine
  • L-Histidine Monohydrochloride
  • L-Alanine
  • L-Cysteine Hydrochloride
  • L-Valine
  • L-Isoleucine
  • L-Leucine
  • L-Phenylalanine
  • L-Tryptophan
  • Glycine
  • L-Threonine
  • L-Proline
  • L-Lysine Hydrochloride
  • L-Tyrosine
  • L-Serine
  • L-Cystine

Lets take a look at the various methods of amino acids testing that NJ Labs can perform.

Amino Acids Testing Methods for Pharmaceuticals and Nutraceutical/Dietary Supplements

Amino acid testing in pharmaceuticals involves analysis and quantification that will ensure the quality, purity, and concentration to meet regulatory requirements as well as ensure the safety and efficacy of the drug products being tested. However, for nutraceuticals/dietary supplements, the focus is more on measuring the amount present because amino acids are the building blocks of proteins and play a crucial role in various physiological functions, therefore making amino acids an important component of many nutritional supplements.

Our amino acids testing methods include:

  • High-Performance Liquid Chromatography (HPLC) :

    HPLC is one of the most common methods used for amino acid analysis. It involves the separation of amino acids in a sample based on their chemical properties, such as polarity and size. Amino acids are detected and quantified using UV or fluorescence detectors. HPLC provides high sensitivity and accuracy, which is crucial for determining amino acid purity and content.

  • Liquid Chromatography-Mass Spectrometry (LC-MS) :

    LC-MS combines the separation capabilities of liquid chromatography with the mass analysis capabilities of mass spectrometry. This technique offers enhanced specificity and can identify and quantify amino acids, even in complex matrices. LC-MS is particularly useful for trace-level analysis and verifying the identity of amino acids

  • Titration :

    While less commonly used in pharmaceuticals, titration can be employed to determine the concentration of amino acids by adding a titrant of known concentration until a specific endpoint is reached. This method is relatively simple but is not as accurate as chromatographic methods. At NJ Labs, we will perform titration only for raw materials.


The Ninhydrin Positive Substances & Ammonium Testing Method

This method is a specialty of NJ Labs and it demonstrates our competency in amino acids testing. It requires state of the art instrumentation to analyze aminos acids potency (assay) and purity. Because primary and secondary amino acids derivatize with a ninhydrin reagent that is readily detectable by UV, any viable amino acid is technically Ninhydrin Positive Substances. The technique includes a bioinert UPLC coupled with post column derivatization. The bioinert UPLC is internally titanium with PEEK tubing, so the reagents do not react with the system and potentially cause interferences. UPLC can handle the high pressure generated by using a specialized ionized HPLC column which allows for the most accurate separations of each amino acid. Post column derivatization is an enhanced system that has the capability to derivatize specific amino acids to accurately quantitate. It also has capabilities to detect amino acid impurities called Ninhydrin Positive Substances & Ammonium. It is a method in amino acid analysis based on the reaction of Ninhydrin with amino groups to form a colored product. The test is often used in conjunction with the Ammonium test for amino acids to confirm the presence of amino acids in a sample. Here’s a brief description of each test:

  • The Ninhydrin Test :

    The Ninhydrin Test is a chemical test used to detect compounds that contain primary or secondary amino groups, a class of organic compounds that serve as building blocks for proteins and are sometimes found in pharmaceutical formulations. Ninhydrin is a chemical reagent that reacts with primary and secondary amines, such as those found in amino acids, to produce a colored compound. The reaction between Ninhydrin and these amino groups forms a purple-blue complex, known as Ruhemann’s purple. The intensity of the color is proportional to the concentration of amino groups present. The appearance of the purple-blue color indicates the presence of primary or secondary amino groups, which are characteristic of amino acids. This test is often used for the qualitative identification of amino acids in pharmaceutical formulations.

  • The Ammonium Test :

    The Ammonium Test is used to detect the presence of ammonium ions (NH4+) in pharmaceutical products. Ammonium ions can be found in certain drugs, excipients, or contaminants and may need to be quantified for quality control purposes. The Ammonium Test typically involves the use of a reagent that reacts with ammonium ions to form a colored or turbid solution. The development of a color change or turbidity indicates the presence of ammonium ions in the sample. The intensity of the color change or turbidity can be used to estimate the concentration of ammonium ions present.

Both the Ninhydrin Positive Substances test and the Ammonium test are valuable tools in amino acid analysis, helping to identify and confirm the presence of amino acids in various samples.

The Post-Column Method

The post-column method for amino acid analysis is a technique used to separate, identify, and quantify amino acids in a sample. This analysis involves liquid chromatography (LC) where hydrolyzed amino acids are injected into a chromatographic system or column, which separates the amino acids based on their chemical properties, such as size, charge, and hydrophobicity. The term “post-column” in this method refers to the fact that the derivatization of amino acids (the formation of colored compounds) occurs after they exit the chromatographic column. The colored derivatives produced in the post-column derivatization reaction are detected by a UV or fluorescence detector. The detector measures the absorbance or fluorescence intensity at specific wavelengths, and this signal is used to quantify the level of individual amino acids. The post-column method for amino acid analysis offers high sensitivity, specificity, and accuracy, making it a valuable tool for a wide range of applications where precise amino acid quantification is essential, particularly in pharmaceutical quality control.

NJ Labs – Your Partner for Ensuring Amino Acids Testing Quality

NJ Labs provides quality amino acid testing that is crucial in pharmaceutical manufacturing to ensure that the concentration of amino acids in the product meets the specified requirements for quality and purity. Additionally, our testing adheres to regulatory guidelines and standards, such as those set by the United States Pharmacopeia (USP), which outline the requirements for amino acid testing and other quality control procedures. Our amino acids testing for nutraceutical and dietary supplement manufacturers ensures that the product contains the specified amount of amino acids in the correct concentrations. We will also help nutraceutical and dietary supplement manufacturers comply with regulatory guidelines and standards, such as those set by organizations like the U.S. Food and Drug Administration (FDA) and industry-specific organizations. These guidelines ensure that products are accurately labeled, meeting the promised amino acid nutritional content of these supplements. Together, we are your partner for ensuring Amino Acids testing quality.

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