Amino Acids and Polypeptides

Amino acids are compounds that combine to form proteins. They are also needed for vital processes such as the synthesis of hormones and neurotransmitters, as well as the building of protein.

If you would like to buy amino acids for your research projects, we have a wide range of products for you. Scroll down to view our full range of amino acid research hormones and polypeptides for sale.

What are Amino Acids?

According to scientific research, amino acids are organic compounds composed of oxygen, hydrogen, nitrogen, and carbon.

When proteins are broken down, amino acids are left. They are used to make proteins, which help grow[i], repair, break down food, and create energy. Ultimately, amino acids function as a source of energy and are classed into three groups:

  • Essential amino acids
  • Nonessential amino acids
  • Conditional amino acids

Essential Amino Acids

Your body requires 20 different amino acids to function optimally. However, only nine amino acids are considered essential: histidine, isoleucine, leucine, tryptophan, valine, lysine, methionine, phenylalanine, and threonine.

Nonessential Amino Acids

Nonessential amino acids include: alanine, arginine, asparagine, aspartic acid, glycine, proline, serine, tyrosine, cysteine, glutamic acid, and glutamine.

Conditionally Essential Amino Acids

Conditional amino acids are mainly essential in times of illness and stress. These acids include: arginine, cysteine, glutamine, ornithine, proline, serine, tyrosine, and glycine.

What is a Polypeptide?

Polypeptides are chains of amino acids[ii] linked together by protein bonds. Short polypeptides are named based on the number of monomeric amino acids that make them. For example, a dipeptide is comprised of two amino acids sub-units and a tetrapeptide is made of four amino acid sub-units.

At the end of every polypeptide, known as the amino terminal, there is a free amino group. At the other end, there is a free carboxyl group known as the carboxyl terminal.

A polypeptide amino acid sequence is determined by the codons in the mRNA molecules from which it was converted.

Buy Amino Acids Online 2024

Are you wondering where to buy amino acids online for your research purposes? We have a number of research amino acids for sale below for you to browse through. From polypeptides to tripeptides and more, we have everything you need for your scientific research. Purchase peptides from the United States here.

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Importance of Amino Acids and Polypeptides

According to studies[iii], amino acids play a vital role.

Currently, scientists are performing extensive amino acid and polypeptide research to gain a fuller understanding of their effects. Amino acids in medicine are continually being explored in clinical research and in animal studies for more information on their functions. While not FDA-approved, you can buy polypeptides and amino acid proteins for your research studies as of May 2024.


[i] Knoop, Andre, Andreas Thomas, Eric Fichant, Philippe Delahaut, Wilhelm Schänzer, and Mario Thevis. “Qualitative Identification of Growth Hormone-Releasing Hormones in Human Plasma by Means of Immunoaffinity Purification and LC-HRMS/MS.” Analytical and Bioanalytical Chemistry 408, no. 12 (February 15, 2016): 3145–3153. doi:10.1007/s00216-016-9377-3.

[ii] Dillon, Edgar L., Melinda Sheffield-Moore, Douglas Paddon-Jones, Charles Gilkison, Arthur P. Sanford, Shanon L. Casperson, Jie Jiang, David L. Chinkes, and Randall J. Urban. “Amino Acid Supplementation Increases Lean Body Mass, Basal Muscle Protein Synthesis, and Insulin-Like Growth Factor-I Expression in Older Women.” The Journal of Clinical Endocrinology & Metabolism 94, no. 5 (May 1, 2009): 1630–1637. doi:10.1210/jc.2008-1564.

[iii] BARRETT, EDWARD J. “COMMON POLYPEPTIDE SECONDARY STRUCTURES.” Assembly Instructions for Polypeptide Models (1982): 18–20. doi:10.1016/b978-0-12-462431-3.50009-1.