Cluster Tubes

What are Cluster Tubes?

Cluster tubes are 1.2 mL polypropylene tubes arranged in either a 96-well individual format (96 tubes in a standard 96-well microplate-footprint rack) or an 8-strip format (8 tubes connected in a strip sized to fit one column of a 96-well block), used for multi-sample storage, screening, dilution series preparation, compound dispensing, and PCR-adjacent molecular biology workflows. Unlike 0.2 mL PCR strip tubes optimized for thin-wall thermal cycling, cluster tubes have a 1.2 mL per-tube volume, making them suited for master mix preparation, sample banking, cherry-picking for automation, and high-throughput assay staging where larger volumes per well are required. Polyethylene 8-cap strips close the tubes securely. Choose individual-format 96-well cluster tubes for sample banking and automated cherry-picking workflows; choose 8-strip cluster tubes for manual multi-sample preparation steps that mirror the 96-well column format.

What you will find:

• Individual cluster tubes for flexible handling

• Racked cluster tube systems for organized storage

• Polypropylene cluster tubes for chemical resistance and durability

• Low-volume cluster tubes for micro-sample applications

• Tube and cap combinations for secure sealing

• Automation-compatible cluster tube formats for robotic systems

• Sterile and non-sterile cluster tube options

How to Choose Cluster Tubes

Individual Tube vs. 8-Strip Format
Individual 96-well cluster tube formats place 96 separate 1.2 mL PP tubes in a standard 96-well SBS-footprint rack with lid. Each tube can be individually removed, labeled, and stored — ideal for sample banking, cherry-picking, and hit-to-lead compound storage. The 8-strip format presents 8 connected 1.2 mL tubes in a strip that sits in one column of the same 96-well rack; strips cannot be separated into individual tubes for most formats.

Sterile vs. Non-Sterile
Sterile cluster tubes (gamma or E-beam sterilized, DNase/RNase-free certified) are required for cell-based assays, viral plaque assays, and any workflow where contamination invalidates the result. Non-sterile tubes are adequate for compound storage, buffer preparation, dilution series, and non-biological applications. Confirm whether your downstream assay requires sterile tubes before ordering bulk non-sterile stock.

With or Without Rack and Lid
Cluster tubes are available as tubes-only (bulk, no rack), with a 96-well polypropylene rack (with lid), or as pre-assembled rack-and-tube sets. For workflows using an automation liquid handler (Tecan, Hamilton, Beckman Coulter Biomek), the pre-racked format with SBS-footprint dimensions (127.76 × 85.48 mm) is required for instrument compatibility. Confirm your automation platform's deck footprint specification before ordering tubes-only formats.

Cap Strip Compatibility
Polyethylene 8-cap strips fit 1.2 mL cluster tubes and cluster tube strips, providing individual tube sealing. Caps must be purchased separately for most non-racked formats. For automated workflows requiring positive tube identification, 2D-barcoded tube options are available from specialty suppliers.

Volume Considerations
The 1.2 mL per tube is the standard cluster tube volume. The maximum working volume is approximately 1.0 mL. For applications requiring >1 mL per well (deep-well culture, high-volume extraction), deep-well plates (2.0 mL per well, 96-well SBS format) are the appropriate format rather than cluster tubes.

Specifications Context

96-well cluster tubes are manufactured from polypropylene (PP) in standard 96-well SBS footprint (127.76 × 85.48 mm) racks with secure-fit polypropylene lids. Individual tube O.D. is designed to conform to standard 96-well position spacing (9 mm center-to-center), ensuring compatibility with 8-channel and 12-channel multi-channel pipettes. PP is chemically resistant to DMSO (commonly used in compound storage at up to 100%), ethanol, isopropanol, and most aqueous buffers. Cluster tubes are autoclavable at 121 °C for reuse in sterile applications when new sterile tubes are not required. 96-well cluster tube system remains the dominant format for compound storage and sample banking in drug discovery and high-throughput screening (HTS) laboratories.

Choose MBP cluster tubes to keep high-volume work structured, simple, and easier to manage without losing control over individual samples.  Contact MBP for bulk PO ordering and institutional pricing.