Peptide synthesis is the joining of two amino acids to form a peptide bond. A peptide is a flexible chain of up to 50 amino acids.
Over the past 50 years, improvements in protein synthesis chemistry and techniques have made peptide synthesis a prevalent strategy in even high-throughput biological research and the development of new products and medications.
Modern peptide synthesis techniques allow for the creation of novel peptides that can maximize biological responses or other outcomes in addition to peptides already present in biological specimens.
Different companies provide custom peptide synthesis online and a full spectrum of high-quality custom peptide services ranging from standard peptide synthesis to high-throughput peptide library and peptide array synthesis. This page discusses the most important aspects of peptide synthesis, the most common synthesis and purification methods, and the advantages of each strategy.
Increases Productivity
Productivity can be increased by lowering the likelihood of error and increasing throughput. It means that when there are fewer issues in experiments, analysis can proceed further, and more resources, including skills and time, can be allocated. Furthermore, in an automated SPPS process, analysts can deviate from specific protocols with pinpoint accuracy and confidence.
Increases Research Throughput
Another significant benefit of automating custom peptide synthesis is that such workstations streamline the process and increase research throughput. As a result, such automated workstations can increase sample sizes by increasing the number of specimens analyzed on specific surfaces. This, in turn, can improve the overall accuracy of the experiment.
Reduces Error
The solid-phase peptide synthesis process necessitates meticulous attention to detail. When done manually, the observing analyst should closely monitor each step to ensure that no elements become contaminated and that all other processes run smoothly. Furthermore, even the most meticulous analysts are only human and may make mistakes that jeopardize the entire throughput and experiment.
When the entire SPPS process is automated, the risk of error is eliminated. This results in fewer errors and overall losses and increased validity and reliability of results.
Reduces Experimental Costs
The wholesome cost of correcting human errors may sometimes outweigh the potential, resulting in a setback. Not only is the entire process of fixing errors expensive, but it also requires individuals to expend valuable effort and time on such projects. Furthermore, by reducing the likelihood of error by automating the SPPS process, labs can reallocate funds and reduce expenses set aside for such fixes.
Process Of Synthesizing Peptides
Normally, during peptide synthesis, the carboxyl group of the incoming amino acid is connected to the N-terminus of the developing peptide chain. In protein biosynthesis, the N-terminus of the incoming amino acid is connected to the C-terminus of the protein chain.
Amino Acid Coupling
When using incoming amino acids such as diisopropyl carbodiimide (DIC) or dicyclohexylcarbodiimide (DCHC), peptide coupling requires C-terminal carboxylic acid activation (DCC). To highlight a reactive O-acylisourea intermediate, two primary coupling reagents can react with carboxyl groups. A nucleophilic attack through deprotected amino groups on the N-terminus could cause a sudden displacement of the reagent halfway through.
Carbodiimides, on the other hand, can form a reactive intermediate capable of dividing amino acids. As a result, reagents that react with the O-acylisourea intermediate, such as 1-hydroxy benzotriazole (HOBt), can be added to form less-reactive intermediates and reduce the possibility of racemization. Furthermore, any side effects necessitate an investigation of various other coupling agents.
Peptide Cleavage
After several rounds of amino acid deprotection and coupling, the nascent peptide must have all protective groups removed. Strong acids like fluoride, bromide, or trifluoromethane sulfonic acid cleave Boc and Bzl groups, while TFA is used to break Fmoc and tBut groups. The chemical utilized for cleavage depends on the protective system used. The N-terminal protective group of the most recently added amino acid, the C-terminal protecting group (chemical or resin) of the first amino acid, and any side-chain protecting groups are all removed after an adequately executed cleavage.
In this stage, scavengers like deprotection are added to react with free-protecting groups. Due to the significance of cleavage in peptide synthesis, this process should be improved to prevent acid-catalyzed adverse effects.
Peptide Synthesis Strategies
It is critical to understand that the liquid-phase method is one of the traditional yet unique methods scientists use to learn how to produce peptides in vitro. It is considered an extended synthesis process and a labor-intensive and time-consuming process.
It’s a problematic sequence because you must manually remove the product from the reaction solution after each step. Furthermore, such an approach necessitates using different chemical groups to protect the C-terminus of the first amino acid. The most significant advantage of the liquid phase is that the product used in the process is purified at each step.
Peptide Purification
The most versatile and widely used method of peptide purification is reverse-phase chromatography (RPC). By raising the concentration of polar solvents in the mobile phase, conventional HPLC procedures collect polar, hydrophilic molecules in the stationary phase, which are then differently eluted.
RPC separates target peptides from synthesis contaminants such as isomers, deletion sequences, and peptides undergoing side-chain reactions and from side-reaction products with free coupling and protecting groups.
Bottomline
Understanding that different peptide synthesis companies use different mediums and methods to produce peptides is critical. Furthermore, the entire purification strategy is typically based on a combination of separation methods that can exploit a peptide’s physicochemical properties, which include charge, size, and hydrophobicity.
However, in the modern era, it has become critical to match the credibility and sophistication of synthetic chemistry, where several researchers and labs are constantly looking for novel ways to produce cutting-edge medicine. Nonetheless, peptide chemistry is a never-ending research field, and most advances take time to apply to good peptide manufacturing.