Why Disposable Autosampler Vials Are Better Than Reusable Vials for HPLC

Introduction

Autosampler vials are critical components in high-performance liquid chromatography (HPLC) systems, serving as the containers that hold samples for automated analysis. These vials must ensure sample integrity, prevent contamination, and maintain mechanical compatibility with instruments. 

While some laboratories opt to clean and reuse autosampler vials in an effort to control costs, this practice may not be as economical or reliable as it initially appears. In this article, we discuss the reasons why disposable autosampler vials are a better choice for most laboratory operations, and in cases where vials have to be reused, how automatic washers outweigh manual cleaning.

Why Disposable Autosampler Vials Outrank Reusable Ones

A common reason scientists attempt to reuse autosampler vials is the perception of cost savings. However, this belief often does not hold true when considering the complete picture. Proper cleaning procedures for reusable vials are extensive and labor-intensive. An example cleaning protocol is as follows:

• Rinse the vial several times with deionized water to remove bulk residues.
• Perform two rounds of ultrasonication using ethanol, each session lasting 15–20 minutes, to dissolve organic contaminants.
• Follow with two additional rounds of ultrasonication using pure water, each for another 15–20 minutes, to remove residual solvents and soluble impurities.
• Finally, dry the vials at high temperatures (not exceeding 110°C, as otherwise vials may be damaged), to ensure all moisture is eliminated.

This cleaning procedure is resource-intensive. It consumes large quantities of solvents (ethanol and pure water, in this case), significant amounts of electricity for operating ultrasonic cleaners and drying ovens, and valuable human labor to handle and monitor the process. These hidden costs often negate any perceived savings from reusing vials.

Another critical point is that while the vial bodies may be cleaned adequately, vial caps and septa cannot. Caps and septa are composed of polymeric materials that absorb solvents and analytes, making them prone to contamination. Even if the vial itself is cleaned meticulously, reusing contaminated caps and septa can easily compromise sample integrity, leading to inaccurate results, increased background noise, or carryover between samples. These analytical errors can result in costly retests, wasted reagents, and damaged data credibility. 

In contrast, disposable autosampler vials eliminate these risks entirely. Each vial, manufactured under strict quality controls and designed for one-time use, guarantees cleanliness, consistency, and chemical compatibility. In this way, they ensure reliable analytical performance, contributing to better data quality and greater operational efficiency.

When Cleaning Is Unavoidable, Use Vial Washers As Long As Possible

Despite the advantages of disposable vials, certain applications or simply budget constraint may still necessitate vial reuse. In these cases, it is still recommended to avoid manual cleaning methods by deploying automatic washers.

Manual cleaning, even when performed carefully, is inherently inconsistent. Incomplete removal of residues, microbial contamination, or detergent remnants can easily compromise the quality of subsequent analyses. Human error is difficult to eliminate when relying on manual methods, and achieving repeatable, trace-level cleanliness is highly challenging without specialized equipment.

To address these shortcomings, automatic vial washers provide an efficient alternative. Take Welch Watbule C Series Autosampler Vial Washer as an example. This compact, easy-to-use instrument features dual-layer basket racks that can clean up to 476 vials at once, saving water, electricity, and labor.

• Each vial is held by an individual rack and cleaned by a dedicated spray nozzle, while top and bottom spray arms provide thorough 360° coverage.
• Its waterproof control panel ensures user safety and minimizes water intrusion. Up to 135 cleaning programs can be stored, making it easy to handle different types of contamination. The C13 model also allows real-time monitoring of conductivity, cleaning time, and operational status.
• A built-in collection trough gathers debris like label residues to prevent clogging. The system also features a hot air drying function with dual-layer HEPA filtration, ensuring the vials stay clean after washing.
• In addition to autosampler vials, the C Series can also clean volumetric flasks, Erlenmeyer flasks, Petri dishes, beakers, test tubes, and more with appropriate baskets.

With the help of vial washers, large quantities of vials can be cleaned simultaneously, ensuring thorough removal of contaminants while significantly reducing solvent usage, human labor, and operational costs.

Conclusion

Reusing autosampler vials may seem like an attractive cost-saving measure at first, but the reality reveals significant hidden costs in terms of labor, solvents, utilities, and quality assurance risks. This also includes the cost due to the inability to clean caps and septa, forcing laboratories to replace them when contaminated.

Disposable autosampler vials, by contrast, offer laboratories a straightforward, reliable, and efficient solution. They ensure sample purity, save valuable labor hours, and support high-throughput operations without the burden of intensive cleaning protocols.

At Welch, we produce single-use autosampler vials, crafted from Type I hydrolytic borosilicate glass, and compliant with the United States and European Pharmacopeias. These products, while being advantageous in cost, significantly decrease the likelihood of failed analysis.

In ion-exchange chromatography or PFAS analysis where glass vials may produce errors from their glass material, polypropylene vials are what we recommend. In mass spectrometry where trace impurities from conventional autosampler vials can be detected, we also supply ultra-clean, pre-assembled autosampler vial kits which are dedicated for higher-standard analyses.

For further information and request a quote of Welch’s autosampler vials or vial washers, please contact us at inquiry@welchmat.com.