Biopsy Cassettes, PP, White — 258-4247-W90 | 500/Bag | Caplugs® Evergreen

Biopsy Cassettes with Covers, 1.0 mm Holes, Acetal (POM), White — 258-4247-W90 | 500/Bag Unassembled

Technical Narrative

The Caplugs® Evergreen is a white Acetal (Polyoxymethylene, POM) biopsy cassette with 1.0 mm holes — engineered for the processing and embedding of small tissue specimens where fragment loss through standard 1.5–2.0 mm cassette holes is a documented pre-analytical error risk. The 1.0 mm aperture retains prostate needle cores, GI mucosal biopsy fragments, endocervical biopsies, and tiny shave and punch biopsy specimens that would pass through larger-hole cassettes during xylene clearing — the processing step where tissue dehydration reduces specimen dimensions and increases fragment mobility. White is the universal default for general biopsy processing and is compatible with all tissue-labeling methods including pencil, pen, and laser engraving on the cassette body.

Acetal (POM) is specified over PP for small biopsy cassettes requiring maximum chemical resistance because POM's crystalline polymer structure provides superior xylene resistance, dimensional stability at paraffin wax infiltration temperatures (56–65°C), and resistance to warping or hole deformation under aggressive rapid-cycle tissue processor agitation. PP cassettes can exhibit subtle hole enlargement and dimensional creep under repeated xylene exposure and thermal cycling — a failure mode that increases fragment loss risk in high-throughput small biopsy programs. Acetal's higher crystallinity eliminates this degradation pathway, maintaining the 1.0 mm aperture geometry throughout the cassette service life.

At $140.54 per 500/Bag — $0.2811 per cassette-and-cover pair — the delivers acetal-grade biopsy fragment security at bulk economics for high-volume small biopsy programs. Also available: 258-4248-G90 (Acetal Turquoise 1.0 mm, $140.54/Bag).

Technical Specifications — Caplugs® Evergreen

Small Biopsy Processing Compatibility —

The acetal biopsy cassette with 1.0 mm holes is designed for small tissue fragments requiring maximum fragment retention during processing:

1.0 mm holes are the smallest standard cassette aperture for routine tissue processing fragment retention. For sub-millimeter fragments, consider tissue biopsy foam pads as a secondary containment layer within the cassette.

Chemical & Processing Compatibility — Acetal (POM)

Acetal (POM) provides superior xylene and solvent resistance versus PP — making it the cassette material of choice for high-volume xylene-exposure processing protocols and laboratories running rapid clearance cycles.

Not autoclave-compatible for cassette sterilization — histology cassettes are used with formalin-fixed non-sterile tissue and do not require sterilization before use.

Anatomic Pathology Laboratory Applications

The serves anatomic pathology programs with high prostate needle core biopsy volumes; gastrointestinal endoscopy programs processing small mucosal biopsy specimens; colposcopy and gynecologic pathology for cervical and endocervical biopsy; dermatopathology for punch biopsy and shave specimen processing; hepatology and nephrology for fine needle and core biopsy; cytopathology for cell block processing; and any histopathology setting where small tissue fragment loss in processing is a documented quality problem requiring smaller-hole cassette intervention.

U.S. Manufacturing, Quality & Institutional Procurement

Every Caplugs® Evergreen lot is precision-molded at our California manufacturing facility and subject to rigorous dimensional inspection and material purity verification. We supply hospital systems, reference laboratories, and federal procurement offices under institutional pricing programs with blanket-order support and same-day shipping on stocked inventory. Request a compatibility sample below to validate fit with your processor configuration before committing to volume.

Frequently Asked Questions — Caplugs® Evergreen

Why are 1.0 mm holes specified for small biopsy cassettes?

1.0 mm is the smallest standard cassette aperture size used in routine histology processing for fragment retention. Prostate needle cores, GI mucosal biopsy fragments, and endocervical biopsies can measure 1–3 mm in cross-section after xylene dehydration reduces specimen dimensions — making standard 1.5–2.0 mm cassette holes a fragment loss risk. The 1.0 mm aperture retains specimens that would pass through larger holes during the clearing step. For sub-millimeter fragments, pair with a biopsy foam pad inside the cassette as a secondary containment layer.

Why use Acetal (POM) instead of PP for small biopsy cassettes?

Acetal (POM) provides superior xylene resistance and dimensional stability versus PP at histology processing temperatures. PP cassettes can exhibit hole enlargement and dimensional creep under repeated xylene cycles and rapid thermal cycling — increasing fragment loss risk over the cassette service life. Acetal's crystalline polymer matrix resists this degradation, maintaining the 1.0 mm aperture geometry consistently across the full processing run. Acetal is specified by high-volume biopsy programs where dimensional stability is non-negotiable for small fragment retention.

Is the white color permanent through xylene and paraffin processing?

Yes. The white pigmentation in the is compounded into the Acetal (POM) polymer matrix — not a surface coating. The color is stable through the full histology processing solvent sequence (formalin, ethanol, xylene, paraffin wax) without leaching, fading, or contaminating the embedding medium. Color stability through processing is essential for reliable color-coded specimen identification at the embedding station.