The U‑2D™ system uses precision glass inserts in a 96‑well plate footprint to manage micro‑volume samples for LC/LCMS workflows. This note clarifies what can be sterilized, how to sterilize, and operational caveats so you can integrate U‑2D inserts into GMP/GLP‑aligned procedures.

Insert Construction and Materials

• The 350 µL U‑2D inserts are manufactured from Class A, Type 33 (first hydrolytic) borosilicate glass and feature a geometry designed to resist bubble formation during filling and sampling. 
• When an insert is dropped into a compatible wide‑opening 2 mL screw‑top autosampler vial, it is self‑aligning, eliminating the need for a supporting poly spring. 
• The silicone sealing mat used with the U‑2D system contains no special additives and is approved for LC/MS use. Treat it as you would any 100% silicone cover mat.

Sterilization / Decontamination

• Autoclaving: U‑2D inserts (standard or deactivated/silanized) may be autoclaved in the same manner as other Type‑33 borosilicate glassware. Use your site’s validated steam cycles and drying protocol. 
• Other sterilization: Inserts may be sterilized by non‑steam methods when your SOPs require alternatives (e.g., gas sterilization). Handle as you would typical analytical glassware to avoid residue or etch.

Note on plastics in the U‑2D ecosystem: The rack/base plastics in the U‑2D system have a separate autoclave profile; always consult the appropriate U‑2D FAQ before heat‑sterilizing non‑glass components. (Related U‑2D FAQs differentiate glass inserts vs. plastics and provide integration/centrifugation limits.)

Centrifugation and General Processing

• U‑2D inserts can be processed in a centrifuge similarly to other borosilicate items. Follow your rotor/adaptor specifications and validated g‑limits for plate‑based use (see companion U‑2D guidance for plate assembly g‑rating). 
• Inserts may be stored like standard analytical glass without special restrictions beyond good laboratory practice. 

Best‑Practice Recommendations (Qualification‑Minded)

1. Pre‑clean & document: Prior to first use, rinse inserts with the same grade solvent as your mobile phase (e.g., LC‑MS grade) and document the cleaning lot in your batch record. (Reinforces the vendor’s allowance to treat inserts as typical Type‑33 glass.)
2. Autoclave load geometry: Autoclave inserts unstacked or in perforated cassettes to ensure steam contact and drying; avoid tight nesting that can trap condensate. (Generalization consistent with the “treat like borosilicate glass” guidance.) 
3. Post‑cycle verification: After sterilization, visually inspect for chips, haze, or residues; discard any inserts with defects to maintain sample integrity. (Prudence step for glass managed as analytical ware.)
4. LC/MS compatibility of mats: When LC/MS is sensitive to silicone extractables, keep needle punctures to the minimum necessary and consider fresh mats for critical sequences; this aligns with the statement that the mat is a standard 100% silicone cover mat approved for LC/MS.
5. Self‑alignment advantage: If you transfer inserts into 2 mL vials for injection/storage, leverage self‑alignment to skip poly springs, reducing the risk of spring‑derived particulates or adsorption sites.