Quality Control in Chromatography: How to Prevent Bad Results from Bad Buffers
How do pH changes affect the drug manufacturing process?
During liquid chromatography
Other reasons influencing buffer quality
While some buffers like phosphate and acetate are more stable, others may be more volatile and experience loss over 24 hours.
Buffers for HPLC (High-performance liquid chromatography) are breeding grounds for microbial growth at room temperature. Buffers must be checked for contaminants before use.
Biological buffers in an organic solvent eluent are susceptible to precipitation. Buffers must be inspected for particulate crystals and monitored for changes in concentration.
Buffers should be inspected for a change in color as it indicates degradation. Analysts must measure how long a specific buffer can sit before it changes color.
When preparing the mobile phase during chromatography, buffers can become turbid, i.e., increase opacity. Cloudy buffers must be discarded.
Impact of bad buffers on chromatography instruments
Using bad buffers can adversely impact the quality of instruments over time.
- Without the right buffer quality, the entire system must be flushed.
- If microbial contaminants are present, entire columns and many consumables like pump seals may need replacing. These costs can add up.
- It can take anywhere from a few hours to days to reset the entire system before it can be used again.
- If several consumables and components must be replaced, the entire qualification can be considered invalid and will have to be requalified. This process needs a validation engineer, a highly-skilled resource. Not every metrology team has a validation engineer onsite. Based on the engineer’s availability, requalification can take more than 2-3 days.
Once a system is back online, analysts will have to validate the entire system.
Challenges in validating buffer quality
Degradation, drifting base, and peak tailing in chroma peaks can offer insights into what aspects need adjustment. Overlapping peaks can indicate a loss of resolution. Analysts can use this information to increase column length, decrease particle size, adjust the temperature of the solution, and more. If the RT shifts, there may be an increase of back-pressure in the column from contamination or a clogged frit.
If a bad buffer has been used, the instrument must be tested and checked for trapped air or air bubbles. Leaks must be identified, and the system must maintain constant pressure. This process can take 15-20 minutes.
Next, a set of visual inspections are needed to confirm precipitation, color, and turbidity. Buffer density must be tested too.
Once these steps are done, analysts must verify lot numbers on specific chemicals to detect potential issues with an entire batch of chemicals being used. For UPLC (Ultra Performance Liquid Chromatography) or LCMS (Liquid Chromatography-Mass Spectrometry), buffers should use ultra-pure chemicals.
Checking for buffer quality and the accurate functioning of the chromatography instrument can be cumbersome but it is critical.
Since many aspects of the buffer validation and QC process are manual, they rely on the skill and meticulousness of each team member conducting the test. There is no detailed end-to-end visibility or control of the entire process.
Automated reagent preparation offers quality and efficiency
Fortunately, the entire solution preparation workflow can be automated. Simple, automated reagent preparation solutions like Revo from LabMinds can help eliminate the risk, errors, stress, costs, and delays from the use of bad buffers. Powders and liquids are automatically mixed to create the perfect buffer formulation. Reagents can be prepared ahead of time, even before the team walks through the door.
The entire process reduces the risk of human error with quantities and types of chemicals being used. Chemical containers are bar-coded to prevent mix-ups. Solution creation and expiry dates are imported into ELN and LIMS and printed on the solution labels.
Additionally, the cloud-based platform means the Revo can be operated remotely. With digital inventory tracking and management, teams can automatically track expiration dates and reorder what they need, when they need it. This offers the flexibility to plan in-lab time effectively.
Want hassle-free, reproducible results every time? Learn more about what Revo can do for you.