Why GC Vials Differ from HPLC Vials
GC vials are not interchangeable with HPLC vials. In GC, the vial and septum are part of the heated sample path. The inlet and transfer lines operate at elevated temperature, and the septum is punctured by the autosampler needle while exposed to carrier gas. Under these conditions, septum bleed can produce siloxane background, baseline drift, ghost peaks, and, in mass spectrometric detection, characteristic ions such as m/z 73, 147, and 207. HPLC vials typically operate at lower temperatures and do not expose the septum to the same thermal stress.
The practical consequences are strict dimensional and thermal requirements. GC autosampler vials must match tray geometry, needle depth, and closure height. The septum must reseal after puncture and remain within its rated temperature. Headspace GC adds pressure and heating, so the vial body, neck, closure, and septum must form a consistent seal.
2 mL GC Autosampler Vials: Crimp, Screw, and Snap
The 2 mL vial is the standard format for liquid-injection GC autosamplers. ALWSCI lists 2 mL vials in 8-425, 9-425, 10-425, 11 mm crimp, and 11 mm snap formats. Type I borosilicate glass is used in the 2 mL vial range. The 2 mL standard vial is 12 × 32 mm. High-recovery and PFAS plastic bottle options are also available. A 1 mL shell vial and 5 mm / 6 mm micro-inserts support limited-volume work.
Representative part numbers:
- C0000001: 2 mL clear 8-425 screw vial
- C0000008: 2 mL clear 9-425 screw vial with graduation marking
- C0000014: 2 mL clear 11 mm crimp vial
The 2 mL 8-425 screw vial is listed at 100 pcs/box.
| Vial type / nominal volume | Thread or closure | Closure style | Notes |
|---|---|---|---|
| 1 mL shell | — | — | Limited-volume shell format; verify autosampler geometry. |
| 2 mL | 8-425 | Screw | C0000001; 100 pcs/box for 8-425. |
| 2 mL | 9-425 | Screw | C0000008; graduation marking. |
| 2 mL | 10-425 | Screw | Verify cap and septum compatibility. |
| 2 mL | 11 mm | Crimp | C0000014; crimper/decrimper required. |
| 2 mL | 11 mm | Snap | Snap closure; verify tray and needle. |
| 4 mL | 13-425 | Screw | Larger volume for preparation. |
| Headspace 10/20/30/50/100 mL | 20 mm | Crimp | Molded crimp; 20 mm natural PTFE/blue silicone 3 mm septa. |
| Headspace 6 mL | Screw-thread | Screw | High-recovery screw headspace vial. |
| EPA VOA/TOC 40 mL | 24-414 | Screw | 27.5 × 95 mm. 20 mL VOA/TOC vials also available; confirm closure with supplier. |
| Caps and septa | 9-425, 11 mm, 13-425, 18 mm, 20 mm, 24-400 | Screw/crimp/snap as applicable | Septum material and temperature must be matched to method. |
GC Headspace Vials: 10/20 mL Crimp vs Screw-Thread
GC headspace vials are heated to drive volatile analytes into the headspace. The septum is exposed to both temperature and internal pressure. Molded crimp headspace vials are available in 10, 20, 30, 50, and 100 mL. A 20 mm natural PTFE/blue silicone septum with 3 mm thickness is listed for this format. A 6 mL screw-thread high-recovery headspace vial is also available. In the broader cap and septum range, 18 mm closures are listed. If an 18 mm screw-thread headspace vial is required, confirm neck dimensions, seal geometry, and compatibility with the headspace sampler before method lock.
Crimp vs screw-thread:
- Crimp: consistent seal geometry when correctly crimped; requires crimper and decrimper. Available in 10/20/30/50/100 mL molded formats.
- Screw-thread: easier manual closure; current high-recovery headspace option is 6 mL. Verify pressure rating and septum choice.
- 18 mm closures: listed in the cap/septa range; confirm headspace vial neck and sampler compatibility before specifying.
Septa for GC: Material and Temperature Limits
Septa selection is driven by inlet or headspace temperature, needle type, and required inertness. The following temperature limits are product-specific listed values for ALWSCI septa:
| Septum material | Listed temperature limit | Notes |
|---|---|---|
| PTFE | 225°C | High-temperature barrier face. |
| PTFE/silicone | 200°C | General GC and headspace use; verify method. |
| Pre-slit PTFE/silicone | 200°C | For autosampler needles; pre-slit. |
| PTFE/silicone/PTFE | 200°C | Autoclavable. |
| PTFE/red rubber | 90°C | Lower-temperature applications. |
| Grey chlorobutyl rubber | 100°C | Lower-temperature applications. |
| Butyl rubber | Available in septum range | Confirm exact part temperature limit. |
General analytical guidance: silicone provides resealing, while a PTFE face reduces interaction with sample vapors. Pre-slit septa are intended for autosampler needle penetration; evaluate seal integrity for the method. Do not exceed the listed temperature limit for the selected septum.
Amber vs Clear Glass
Clear glass allows visual inspection of sample level, particulates, and phase separation. Type I borosilicate glass is specified in the 2 mL vial range. Representative clear part numbers include C0000001, C0000008, and C0000014. Amber glass is the conventional choice for light-sensitive analytes; it reduces photodegradation risk but does not replace method-specific protection. Where amber is required, confirm the specific volume, thread, closure, and septum in the current range before validation.
QC and Batch Traceability
Vial performance depends on dimensional consistency and lot-to-lot control. ALWSCI operates under ISO 9001:2015, ISO 14001:2015, ISO 45001:2018, ISO 13485:2016, and ISO/IEC 17025:2017. Certificates are available upon request.
QC includes a team of 10+ personnel, sampling and patrol inspection, and retained samples for each batch and order for at least 2 years. SGS reports, COA per batch, and MSDS are available. A Bureau Veritas factory inspection report is also available. The Varefied brand covers certified vials and closures.
Manufacturing is supported by 3 manufacturing and R&D bases, 200+ production lines, annual capacity of 3 billion pieces, a 50,000 m² base, 20,000 m² cleanroom, and 8,000 m² warehouse. Export coverage is 110+ countries. The patent portfolio includes 9 invention patents and 39 utility model patents. For purchasing engineers, the relevant documentation package typically includes COA, lot traceability, and retained-sample records. Certificates are available upon request; a COA accompanies every shipment.
Selection Checklist for GC Vials and Closures
- Identify the autosampler or headspace sampler model and tray.
- Confirm vial volume: 2 mL, 4 mL, 6 mL headspace, 10/20/30/50/100 mL headspace, or 20/40 mL VOA/TOC.
- Match closure: 8-425, 9-425, 10-425, 11 mm crimp, 11 mm snap, 13-425, 18 mm, 20 mm, 24-414, 24-400.
- Select septum material and confirm the listed temperature limit exceeds the inlet or headspace method temperature.
- Check needle gauge, needle length, and whether a pre-slit septum is required.
- Confirm sample chemical compatibility with glass, septum, and closure.
- Decide clear vs amber based on analyte photostability.
- Consider high recovery, 1 mL shell, and 5/6 mm micro-inserts for limited volume.
- Verify cap torque and crimp setting; use crimper/decrimper for crimp formats.
- Request COA, SGS, MSDS, and lot traceability for the ordered batch.
- Confirm packaging: 2 mL 8-425 screw vials are listed at 100 pcs/box.
- Confirm lead time: stock 2–5 days, production 15–25 days, ODM/OEM 30–90 days.
- MOQ is not hard-set; for overseas orders, a suggested minimum of ≥1,000 pcs applies.
Ordering and Technical Support
ALWSCI provides OEM/ODM services. Customization dimensions include size, material, color, logo, barcode, packaging, mold, silanization, and Ultra-Clean treatment. Agents and distributors are recruited. For method-specific selection, send the autosampler model, vial format, septum material, temperature, and sample matrix.
Contact:
- International business department: marketing@alwsci.com
- Phone: +86 571 8883 7380
- Fax: +86 571 8801 2781
- Factory: ALWSCI Smart Industrial Park, No.269 Haidong Road, Binhai New District, Shaoxing, 312366, Zhejiang, China
- Office: B410, No.525 Shixiang Road, Gongshu District, Hangzhou, 310011, Zhejiang, China
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