Essential HPLC Vial Accessories for Reliable Chromatographic Analysis

An Overview of Essential HPLC Vial Accessories for Chromatographic Analysis

May. 22nd, 2024

 Accessories commonly used in HPLC vials

A chromatography sample vial is used for automatic chromatography sampling by LC, GC, MC and other automatic injectors and headspace samplers. HPLC vial accessories are additional components that complement the functionality of HPLC vials, enhancing their performance and ease of use. These accessories include cap, septas and vial inserts and so on. HPLC vials have low capacity but are the most commonly used. The effectiveness of the experiment, the procedure used to carry it out, and the precision of the results obtained from it depend especially on how sample vials and the items that support them are chosen and used.

Types and Function of HPLC Vials Accessories

Screw Cap

Screw caps are low evaporation and reusable, a sealing method that is less harmful to hands than crimp caps and requires no additional tools.

The screw cap has an excellent sealing effect and mechanically holds the septa in place, requiring no tools for assembly.

Clamp Cap

The sealing effect is very good and can effectively reduce sample volatilization;

When the autosampler injection needle pierces the sample, the position of the septa remains unchanged;

It needs to be used with a clamping tool, such as 11mm, 20mm crimper and decrimper. When sealing, you need to use a crimper. For a small number of samples, a manual crimper is the best choice; for a large number of samples, an automatic crimper can be used.

Snap cap

The sealing effect of Snap caps is not as good as other screw caps and crimp caps;

If the fit of the cap is excessively tight, the cap will be difficult to close and may break;

If it's too loose, the seal is ineffective and the septum may move out of place.

Looking to select the perfect cap for your chromatography vials? Check out our article for expert guidance: How to Choose the Right Cap for Your Chromatography Vials?

The Septa of HPLC Vial

PTFE/silicone Septa, using glueless bonding technology, have both the corrosion resistance of PTFE and the sealing performance of silicone. They are the most common anti-corrosion Septa currently on the market.


Suitable for multiple injections and sample storage.

Excellent resealing characteristics.

Has the chemical resistance of PTFE before piercing, and the septum will have the chemical compatibility of silicone after piercing.

Pre-slit PTFE/silicone

Provides good ventilation to prevent vacuum from forming within the vial, resulting in excellent sampling reproducibility.

To prevent the occurrence of the bottom needle getting clogged after injection, use a blunt or fine needle.

It can be punctured without creating negative pressure, and following continual injection, the pressure within and outside the bottle can be balanced.

Unsure how to pick the ideal septa for your chromatography vials? Explore our article to learn how to choose the right septa for your needs: Premium PTFE and Silicone Septa: Reliable Sealing Solutions.

The Micro Inserts of HPLC Vial

Micro inserts are small, cylindrical devices designed to fit inside standard chromatography autosampler vials. They are typically made of borosilicate glass or inert polymers. Micro insert could minimize sample dead volume and maximize sample recovery. Micro inserts are used to contain small sample volumes, reduce surface interactions. And improve chromatographic performance by providing a more controlled environment for sample injection. Effectively relieves the pressure of syringe.

Micro Inserts can be used on all 1.5ml-2ml vials. These vial insert Suit for 8-425, 9mm, 10-425, 11mm hplc vial. 150ul, 250ul, and 300ul micro inserts are provided. Different bottom shape for choosing, including flat bottom, concial bottom, and concial bottom with polyspring. Pulled point inserts are more economical, enables better sample recovery. The conical vial insert decreases the surface area inside the vial. PolySpring inserts are self aligning.

Looking to select the optimal micro-insert for your chromatography vials? Check out our article for expert guidance on finding the perfect insert solution: How to Choose the Right Type of Micro-Insert for Your Chromatography Vials?

HPLC Vial Accessories Requirements and Precautions

There are several points to note when using HPLC autosampler vials and accessories:

1.The cap of the hplc vial should be screwed properly, otherwise it will affect the sealing and cause the septa to fall off and become misplaced. When the cap is properly tightened, the septa will appear flat or slightly concave. If it's too tight, the septa can cup or dent. If it is too loose, the syringe cannot penetrate the septa of the sample vial and insert into the vial, causing sampling failure.

2.Do not overfill the sample vial. Generally speaking, the liquid level in the vial should be kept below two-thirds of the height in the vial. If the liquid level is too high and the injection volume is relatively large, negative pressure will easily occur in the sealed sample vial, which will affect the accurate extraction of liquid by the injection needle, and may even produce bubbles in the needle, resulting in poor injection repeatability.

3.When the sample is precious or the sample amount is limited, you can use a sample vial insert or a high-recovery sample vial, and you can also adjust the position of the sample needle tip during sampling to maximize the use of the limited sample.

4. Measure the distance between the bottom of the vial and the tip of the needle during injection. Avoid hitting the bottom of the HPLC vial with the needle tip. Don't damage the injection needle.


To sum up, HPLC vial accessories are critical to chromatographic performance and vial functionality. By using high-quality accessories, researchers can reduce the risk of contamination, maintain sample integrity, and obtain accurate, reliable results.