1. A peptide is built step-by-step by adding amino acids in a precise sequence on a solid resin.

2. After each addition, excess chemicals are washed away and protective groups are removed to prepare for the next step.

3. The finished peptide is cleaved from the resin and purified, typically using HPLC.

4. The purified peptide is turned into a solid or liquid product. Quality control tests are run throughout to ensure purity, safety, and effectiveness.

protection and coupling icon

1. Protection and Coupling

deprotection and peptide elongation icon

2. Deprotection and Peptide Elongation

peptide icon

3. Cleavage and Purification

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4. Formulation and QC

1. Peptide-producing bacteria or yeast are grown in a nutrient-rich medium optimized for high yield.

2. Peptides are separated from the culture using centrifugation and filtration. If inside cells, the cells are broken open first.

3. Peptides are purified using techniques like chromatography and tangential flow filtration, followed by any necessary cleavage or modifications.

4. Excipients are added, and the product is tableted or filled into vials, under sterile conditions. Quality control tests ensure purity, safety, and functionality.

icon representing a cell

1. Cell Culture

Harvesting icon

2. Harvesting

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3. Purification and Processing

formulation and QC icon

4. Formulation and QC

Biochemical Synthesis

Biochemical synthesis is a widely adopted method for peptide production, especially for short peptide production, and offers advantages over recombinant biological methods, in certain use cases: 

  • Cost: Manufacturing short peptides is less expensive at small to medium scale production, given simpler infrastructure requirements, fast turnaround time, and standardized resources. However, recombinant methods may be more cost-efficient at larger scales, longer or more complex peptides.

Whether produced through biochemical synthesis or recombinant biological methods, peptide manufacturing remains inherently expensive. Each approach comes with its cost drivers, from reagent and solvent use in chemical synthesis to complex infrastructure and long production cycles in biological expression. As a result, there is a strong drive across the industry to maximize process efficiency, minimize variability, and ensure consistent product quality at every scale.

  • Flexibility: It allows the incorporation of non-coding amino acids and diverse backbone modifications to improve stability.

  • Purity: Chemical synthesis avoids the risk of host-cell contaminants and enables precise control of the product. However, recombinant methods also achieve high purity with proper downstream processing.

Biological Methods

Recombinant biological approaches are common for larger proteins requiring complex post-translational modifications, and are advantageous for peptide production in circumstances such as:

  • Complexity: Biological methods enable complex peptide folding and specific post-translational modifications compared to chemical methods.

  • Sustainability: Chemical methods use an excess of high-purity, expensive reagents and solvents to ensure reaction completion, leading to greater chemical waste, and could affect global supply chains for essential solvents.

  • Peptide Length: Biological methods are better suited for producing longer peptides (>50 amino acids).

Balancing Science and Process in Peptide Synthesis

Many peptide APIs are developed through solid-phase peptide synthesis (SPPS), a stepwise process that allows precise control over sequence and modification. Others, particularly more complex or longer-chain peptides, are expressed in biological systems using microbial or mammalian cells.

While these methods differ in scale and platform, they share a need for rigorous process control and accurate material handling at every stage.

Whether weighing amino acids, solvents, or reagents in the R&D lab or handling kilogram-scale batches in production, accuracy in every measurement matters. Minute variations can affect:

  • Coupling efficiency.
  • Final yield and purity.
  • Reproducibility across batches.

METTLER TOLEDO provides robust weighing solutions for both laboratory and industrial applications. From microbalances that support formulation development to floor scales used in production suites, our equipment delivers the precision and compliance pharma manufacturers require. Integration with software systems also helps ensure full traceability and minimizes manual documentation errors.

Chemical Peptide Synthesis: Enhancing Yield and Purity

Solid-phase peptide synthesis (SPPS) remains the gold standard for producing short to medium-length peptides, including therapeutic APIs like GLP-1 analogues or calcitonin. However, SPPS workflows can be complex, involving:

  • Precise addition of protected amino acids.
  • Efficient removal of protecting groups.
  • Solvent management and reaction control.

Understanding the progress of peptide coupling reactions is critical. In-situ FTIR and Raman spectroscopy tools by METTLER TOLEDO provide real-time insight into each step of synthesis, allowing scientists to monitor deprotection and coupling reactions, identify incomplete reactions early, and reduce overuse of costly reagents.

Controlling temperature, stirring, and reagent addition precisely across different synthetic steps using Automated Reactors such as EasyMax™ and OptiMax™ helps with the optimization of reaction conditions, the development of a safe scale-up from milligrams to kilograms, and the achievement of high reproducibility for tech transfer.

pH control is critical for peptide cleavage and purification. METTLER TOLEDO provides InPro series sensors that are tailored for use in harsh solvents, ensuring robustness and regulatory compliance during acidic cleavage or basic wash steps.

Biotechnological Peptide Production: Scale with Control

Many peptides, especially interferons, enzymes, or fusion peptides, are produced using recombinant technologies in microbial or mammalian systems. These processes require strict environmental control and real-time monitoring to maintain cell viability, protein expression, and product quality.

pH, dissolved oxygen (DO), CO₂, and conductivity must be precisely controlled during fermentation. ISM sensors from METTLER TOLEDO provide reliable real-time measurements, predictive diagnostics, sensor lifecycle management, and integration with PAT (Process Analytical Technology) strategies.

Purification, Formulation, and Final Quality

Once synthesized or expressed, peptides undergo multiple steps of purification and formulation before reaching their final drug form. Reverse-phase HPLC, ultrafiltration, and lyophilization are common techniques used to achieve the purity and stability required for therapeutic use.

Accurate preparation of buffers, solvents, and excipients is critical at this stage. Inconsistent concentrations or pH deviations can reduce recovery or compromise product stability. Whether during ultrafiltration prep, final formulation blending, or freeze-drying optimization, precision and reproducibility are non-negotiable.

Weighing equipmentpH meters, and UV/Vis spectrophotometers integrated into lab or production environments enable reliable downstream execution and QC in peptide manufacturing. Importantly, when the generated data is centrally collected and managed, it strengthens traceability and supports regulatory documentation.

Additionally, high-precision moisture analysis and water content determination by KF titration support final formulation and stability testing, key in freeze-dried peptide products. Whether during development or commercial QC, laboratory software solutions ensure consistent analytical data for required regulatory compliance and product quality.

Product Inspection: A Final Check for Patient Safety

From initial amino acid weighing to final vial inspection, each step in the peptide production journey demands precision. As products near release, automated product inspection systems serve as a critical safeguard before products leave the facility. For peptide therapeutics, this includes:

  • Fill level control: Checkweighing, vision inspection and X-ray inspection monitor, measure and regulate fill levels to meet strict dosage and regulatory specifications.

  • Quality and integrity checks: Checkweighing, vision inspection and X-ray inspection perform integrity checks to help ensure pharmaceutical packages meet regulations and deliver safe, complete products to consumers.

  • Label quality inspection: Vision inspection for label quality control to detect label-related defects and mitigate the risk of product recalls.


Product Inspection solutions from METTLER TOLEDO are designed for high-efficiency pharmaceutical environments, offering:

  • GMP-compliant systems that integrate easily into existing lines.

  • Traceable performance verification for audit-readiness.

  • Support during the specification and qualification process, from evaluating the right application, selecting suitable product testing equipment and professional installation through to dedicated Equipment Qualification packs (EQpack) for efficient validation processes.

These systems not only protect product quality but also strengthen brand integrity and support regulatory compliance with agencies like the FDA, EMA, and global health authorities.

Analytical Sensors for Bioreactors

Analytical Sensors for Bioreactors

Accurate Process Control in Fermentation & Cell Culture

automated-reactor

Automated Lab Reactors, In-Situ Analysis, and Modeling Software

Instruments for Chemical Synthesis, Process Development, and R&D

dynochem biologics

Dynochem Biologics

Bioprocess Simulation Software

Analytical balances - Laboratory balances

Analytical Balances

Unmatched Weighing Results in Your Laboratory

METTLER TOLEDO Precision Balances

Precision Balances and Scales

Accurate and Precise Weighing Equipment for the Laboratory and Manufacturing

UV Vis Spectrophotometry by METTLER TOLEDO

UV/Vis Spectrophotometry

Instruments, Accessories, Services, and Software for UV Vis Spectrophotometry

lab pH instruments

Lab pH Instruments

pH and Conductivity Measuring Solutions for Laboratory and Field Applications

Industrial Scales and Weighing Scales

Industrial Weighing Scales and Systems

Reliable Weight Scales for Manufacturing Environments

Product Inspection | Product Inspection Equipment

Product Inspection Equipment

For Quality Control and Contamination Detection Processes

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