Weak links in the cycle: what happens when biosynthesis chemistry loses consistency?

During biosynthesis, the same chemistry may be repeated hundreds of times. Each reaction cycle builds on the one before it, gradually creating the precise molecular structure the process is designed to produce.That repetition leaves little room for variability. Even small deviations in chemical purity or performance can accumulate across a synthesis run and affect the final product.

Why reagent consistency matters in oligonucleotide synthesis

Oligonucleotide synthesis shows just how much is at stake. Each coupling cycle moves through four distinct chemical steps before the process begins again with the next nucleotide. When that cycle is repeated dozens, or even hundreds of times, a small inconsistency at any one step can result in higher impurities and lower yields.

The four coupling steps where variability enters oligonucleotide synthesis

• Deblocking: An acid solution removes the protecting group so the next nucleotide can attach. If acid strength varies between batches, deprotection performance can change, potentially resulting in incomplete deblocking and affecting the subsequent coupling reaction.
• Activation and coupling: The incoming nucleotide is activated for coupling to the growing chain. This is particularly sensitive to water. Even trace moisture can compete with the intended reaction, reducing coupling efficiency in ways that may not become apparent until the finished sequence is analysed.
• Capping: Acetic anhydride and N-methylimidazole terminate strands that failed to couple, preventing them from reacting in subsequent cycles and creating deletion sequences within an otherwise correct chain. If capping reagents underperform, those failures can continue through later cycles.
• Oxidation/sulfurisation: An iodine solution converts the phosphite linkage into the stable phosphate linkage required in the final molecule. Variability in iodine concentration can result in incomplete oxidation, potentially compromising the stability of the backbone.

Each step shares a requirement: the solvents and reagents behind them must perform consistently from the first cycle to the last. Consistency is key at every step and purity makes it possible.

Scaling up: how reagent variability becomes a production risk

As biosynthesis moves from the bench toward production, small sources of variability can become larger risks. Trace carryover that may have little measurable effect at small scale can become more consequential across larger volumes and repeated batches.

When multiple reagents move through shared equipment, the potential for cross-contamination adds another variable to a process built on consistency. Dedicated, closed-system processing helps control that risk by keeping reagent classes separated during manufacturing and reducing opportunities for one product’s chemistry to influence another.

as delivery scales from research quantities to therapeutic production, purity standards need to scale with them, batch after batch, without exception

That same attention to purity must continue after manufacturing. For water-sensitive synthesis, the container itself can become another source of variability if moisture enters during storage or dispensing. Solstice testing showed that its stainless steel pressure dispense system (SSPDS) maintained consistently low water content across three 200 L containers of Burdick & Jackson BioSyn acetonitrile. Even after five months of storage, water content remained unchanged at 0.001%, demonstrating that high-purity chemistry can be protected as workflows move to production-scale volumes.

At production scale, the consequences of inconsistency grow along with the process. A failed batch can mean lost materials, time, and production capacity, and ultimately another delay in moving promising therapeutics forward.

High-purity solvents in mRNA, siRNA and lipid nanoparticle formulation

Purity requirements extend beyond oligonucleotide synthesis. The need for consistent chemistry doesn’t end when a sequence is built. mRNA and siRNA therapeutics increasingly rely on lipid nanoparticle (LNP) formulations for delivery, where performance can depend on the purity of every component, from the lipids themselves to the solvents used in formulation. In these precise systems, impurities can affect critical characteristics such as particle size, encapsulation efficiency, and stability.

Peptide synthesis has a similar need for precision. Cleavage and deprotection steps require the same attention to consistency as the coupling reactions used to build the sequence, helping ensure the finished peptide matches its intended design.

As these delivery formats scale from research quantities to therapeutic production, purity standards need to scale with them, batch after batch, without exception.

High-purity reagents engineered for biosynthesis workflows

Future cures demand flawless chemistry. Burdick & Jackson BioSyn high-purity solvents and reagents are engineered for the consistency biosynthesis demands. Advanced purification methods and tightly controlled, closed-system processes help protect against cross-contamination and variability, while dedicated production equipment and rigorous analytical testing support reproducible lot-to-lot performance.

Backed by more than 65 years of solvent excellence, Burdick & Jackson BioSyn combines custom formulations, packaging engineered to preserve purity from bench to production, and expert support to help researchers maintain reliable performance as workflows grow.

With high-purity chemistry engineered for biosynthesis, scientists can spend less time managing variability and more time shaping what comes next in medicine and advancing therapeutics from concept to clinical reality.