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HomeNon-Animal Origin (NAO) Amino Acids for Drug Discovery & Development

Non-Animal Origin (NAO) Amino Acids for Drug Discovery & Development

A laboratory technician wearing purple nitrile gloves, safety goggles, and a white lab coat pipetting red cell culture media from a glass flask into a 6-well cell culture plate inside a biosafety cabinet.

What are NAO amino acids?

Non-animal origin (NAO) amino acids are high-purity building blocks produced without the use of any animal-derived raw materials. The terms non-animal origin (NAO) and animal-origin-free (AOF) are used across the life science industry and synonymous with the non-animal source amino acids described on our product detail pages. Typically, NAO amino acids are produced through fermentation or chemical synthesis using plant-based, recombinant, or synthetic sources.

They are specifically designed to meet the stringent quality and regulatory requirements of pharmaceutical, biotechnology, and cell culture applications. The use of NAO amino acids minimizes the risk of contamination from animal-derived components, thereby enhancing product safety, compliance and reproducibility. In addition, they support ethical sourcing practices and align with the industry’s growing preference for sustainable, traceable and non-animal origin raw materials. Consequently, NAO products have gained significant attention in drug discovery and development.1

We offer a portfolio of ≥98% pure and scalable NAO amino acids for specific use in pharmaceutical and biotechnology industries. One of our key objectives is to support researchers and manufacturers across R&D, analytical, and production functions by providing a high-purity, reliable, consistent, and scalable portfolio for their evolving needs.

Importance of NAO products

NAO products are increasingly important in biopharmaceutical development. The biological origin of animal-derived materials can introduce contamination risks that may compromise data quality, reliability and translatability of clinical outcomes. This can further lead to increased regulatory scrutiny.2 Among NAO products, amino acids have gained significant attention across biochemistry, peptide synthesis, cell culture media development, and monoclonal antibody (mAb) production (Table 1). By eliminating concerns associated with animal-derived raw materials, NAO products support more robust manufacturing processes. The key challenges associated with animal-derived products, their potential risks, and the significance of NAO amino acids are summarized in Table 1. 

NAO amino acids serve as an essential component of chemically defined, animal-free media systems used in mAb production, enabling more controlled cell culture processes. Furthermore, their chemically defined, animal-free composition enables precise and reproducible media formulation, supporting consistent cell growth and high productivity while helping maintain critical quality attributes (CQAs) that directly influence mAb safety and efficacy, particularly in CHO cell culture systems.  Consequently, the use of NAO amino acids enhances process reproducibility while supporting consistent cell growth.7, 8, 9

NAO products are increasingly recognized as key enablers of global regulatory compliance throughout clinical development by reducing the biological risks and supply-chain challenges associated with animal-derived materials. Their adoption supports cGMP compliance across major global regulatory authorities, including the U.S. Food and Drug Administration (FDA), European Medicines Agency (EMA), Health Canada (HC), UK Medicines and Healthcare products Regulatory Agency (MHRA), and Australia's Therapeutic Goods Administration (TGA), and Japan's Pharmaceuticals and Medical Devices Agency (PMDA), while reducing the need for extensive risk assessments and origin documentation. Their defined, reproducible composition also minimizes lot-to-lot variability, supporting process consistency, method validation, and regulatory submissions.10, 11, 12

A blue prohibition sign showing a rat inside a circle with a diagonal slash through it, indicating non-animal origin

Our expertise in NAO amino acid portfolio

Our portfolio is engineered to meet the most demanding requirements of modern biopharmaceutical research. Designed to deliver exceptional quality, safety, and reliability, our portfolio addresses key limitations associated with conventional animal-origin products. Endotoxin contamination can trigger pyrogenic responses and compromise cell culture integrity. Our manufacturing protocols include stringent endotoxin screening.

This provides an important layer of quality assurance for mammalian cell culture systems such as HEK293 and CHO platforms, where elevated endotoxin levels can adversely affect cell viability, productivity, and CQAs.

Key features and considerations

  • Exceptional purity: ≥98% pure and animal component-free

Our NAO amino acids are manufactured to a purity of ≥98%, meeting the demanding requirements of cell culture, biologics development, and pharmaceutical manufacturing. This high purity ensures consistent and reproducible performance from R&D through industrial scale-up. In addition, the products are free from animal-derived components, including serum, helping to ensure safer and controlled bioprocessing workflows.

  • Enhanced safety and contamination control

Conventional animal-derived amino acids can introduce biological contaminants (including TSE/BSE agents). Our portfolio, produced through animal-free manufacturing process, avoids this contamination source, reducing bioprocessing risks. This minimizes the likelihood of batch failures, product recalls, and development delays. Serum-free cell culture media (SFM) formulated with chemically defined, non-animal origin components, offers improved safety, and regulatory compliance by reducing significant batch-to-batch variability.13

  • Scalable supply: Up to 10 kg scale

A key strength of our portfolio is its scalable supply, from milligram quantities to 10 kg, ready to ship, supporting workflows from early-stage research and process development to commercial biologics manufacturing. They are available in the required quantities while preserving both quality and the integrity of the animal-free supply chain. Products such as L-Glutamine (G8540) and L-Leucine (L8912) are available in pack sizes ranging from 10 mg to 10 kg, supporting seamless scale-up and production.

Applications in drug discovery & development

The transition from discovery to development requires increased characterization, specification, and control of raw materials. Amino acids used during drug discovery may become formally specified raw materials during drug development. Subsequent changes to raw materials may require additional documentation and risk assessment in accordance with ICH Q8 and Q11 principles.

  • Cell-based screening and target validation

Cell-based assays are the foundation of target validation and compound screening. The amino acid composition of basal media is part of the assay definition. Non-animal-derived amino acid sources reduce lot-to-lot variability that can impact drug effects.14

  • Mammalian protein expression (HEK293, CHO)

HEK293 and CHO cells are widely used for recombinant protein expression during early drug candidate characterization. In CHO batch cultures, depletion of key amino acids, including L-glutamine, L-cysteine, L-methionine, L-asparagine, and L-tyrosine, can affect protein titer, glycosylation profiles, cell viability, and metabolic efficiency. NAO amino acids help to reduce raw material variability and establish a consistent specification baseline from discovery through development.9

  • Peptide based drugs and GLP-1 receptor agonists

Peptide therapeutics, including GLP-1 receptor agonists, peptide-drug conjugates, and cyclic peptides, represent a rapidly growing area of drug development. NAO amino acids support key workflows spanning amino acid analysis, peptide solubility and stability testing, cell-based characterization assays, and structural biology.15

  • Early process development and media optimization

In Design of Experiments (DoE)-based media optimization, well-defined inputs are a prerequisite for meaningful experimental design. NAO amino acids support this consistency across key development areas, including fed-batch feed strategies, serum-free and chemically defined media, and CMC documentation.

  • Cell and gene therapy manufacturing

CGT manufacturing faces the most stringent raw material requirements in the industry. The 2024 FDA guidance explicitly identifies minimization of animal-derived components as a development goal for both viral vector production and ex vivo cell therapies.10

NAO amino acids are categorized below according to their primary workflow applications. Products with applications across multiple workflows may appear in more than one group.

Conclusion

Building on the risk-mitigation and compliance benefits outlined above, NAO amino acids have become an essential component of modern biopharmaceutical and biotechnology workflows, offering a safer, more consistent, and regulatory-aligned alternative to conventional animal-derived materials. These products ensure greater reliability across multiple drug development workflows by enhancing process reproducibility and supporting ethical and sustainable sourcing practices.

We offer high-quality products manufactured under stringent quality standards and supported by rigorous quality control (QC) testing to ensure purity. With advanced manufacturing capabilities, we provide NAO amino acids with customization options to meet specific application requirements. Combined with an animal-free supply chain and scalable availability, these materials strengthen process control, enhance supply chain resilience, and support evolving global regulatory requirements throughout the drug development life cycle. As the pharmaceutical industry continues to move toward safer, more sustainable, and animal-component-free development strategies, NAO amino acids provide opportunities for integration across bioprocess development and manufacturing workflows.

Click here to explore the comprehensive portfolio of NAO amino acids.

References

1.
Herdiana Y, Gozali D, Putriana N, Muchtaridi M, Shamsuddin S, Sofian F. 2026. Beyond Side Effect: Immuno-Ethical Risk Analysis of Animal-Derived Ingredients in Pharmaceuticals. Risk Manage. Healthc. Policy. 19:584055. https://doi.org/10.2147/rmhp.s584055
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Duarte AC, Costa EC, Filipe HA, Saraiva SM, Jacinto T, Miguel SP, Ribeiro MP, Coutinho P. 2023. Animal-Derived Products in Science and Current Alternatives. Biomater. Adv. 151213428. https://doi.org/10.1016/j.bioadv.2023.213428
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International Council for Harmonisation (ICH). 1999. Q6B: Specifications: Test Procedures and Acceptance Criteria for Biotechnological/Biological Products. [Internet]. ICH Harmonised Guideline; ICH: Geneva, Switzerland. Available from: https://www.ema.europa.eu/en/ich-q6b-test-procedures-acceptance-criteria-biotechnologicalbiological-products-scientific-guideline (accessed July 15, 2026)
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Fan Y, Jimenez Del Val I, Müller C, Wagtberg Sen J, Rasmussen SK, Kontoravdi C, Weilguny D, Andersen MR. 2015. Amino Acid and Glucose Metabolism in Fed‐batch CHO Cell Culture Affects Antibody Production and Glycosylation. Biotechnol. Bioeng. 112(3):521-535. https://doi.org/10.1002/bit.25450
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U.S. Food and Drug Administration. 2024. Considerations for the Use of Human- and Animal-Derived Materials in the Manufacture of Cell and Gene Therapy and Tissue-Engineered Medical Products. [Internet]. Draft Guidance for Industry; FDA: Silver Spring, MD. Available from: https://www.fda.gov/regulatory-information/search-fda-guidance-documents/considerations-use-human-and-animal-derived-materials-manufacture-cell-and-gene-therapy-and-tissue (accessed July 15, 2026)
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U.S. Food and Drug Administration. 2010. Characterization and Qualification of Cell Substrates and Other Biological Starting Materials Used in the Production of Viral Vaccines for the Prevention and Treatment of Infectious Diseases. [Internet]. Guidance for Industry; FDA: Silver Spring, MD. Available from: https://downloads.regulations.gov/FDA-2018-N-4757-0008/content.pdf (accessed July 15, 2026)
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International Council for Harmonisation (ICH). 1997. Q5D: Derivation and Characterisation of Cell Substrates Used for Production of Biotechnological/Biological Products. [Internet]. ICH Harmonised Guideline; ICH: Geneva, Switzerland. Available from: https://www.ema.europa.eu/en/ich-q5d-derivation-characterisation-cell-substrates-used-production-biotechnological-biological-products-scientific-guideline (accessed July 15, 2026)
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Salazar A, Keusgen M, von Hagen J. 2016. Amino Acids in the Cultivation of Mammalian Cells. Amino Acids. 48(5):1161-1171. https://doi.org/10.1007/s00726-016-2181-8
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Lebedev T, Mikheeva A, Gasca V, Spirin P, Prassolov V. Systematic Comparison of FBS and Medium Variation Effect on Key Cellular Processes Using Morphological Profiling. Cells. 14(5):336. https://doi.org/10.3390/cells14050336
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Elsayed Y, Kühl T, Imhof D. 2025. Regulatory Guidelines for the Analysis of Therapeutic Peptides and Proteins. J. Pept. Sci. 31(3):e70001. https://doi.org/10.1002/psc.70001