Cost

What Drives Cost Per Unit in Single-Use Bioprocess Assemblies

A money-focused breakdown of single-use assembly cost per unit, how to build a defensible quote across volume breaks, and the five spots where estimates go wrong.

On a single-use assembly, materials usually run 55 to 70 percent of cost per unit, direct cleanroom labor 15 to 25 percent, sterilization 5 to 12 percent, in-process and release testing 5 to 10 percent, and overhead plus margin the balance. A mid-complexity 50 liter bag manifold with 6 connectors and 4 filters lands around $180 to $320 per unit at moderate volume. Build the quote bottom up from the bill of materials, not top down from a target price. The mistake that kills margin is treating this like machined parts, where labor dominates. Here the connectors and filters set the floor.

Price the BOM line by line. Aseptic connectors run $18 to $65 each, so 6 connectors alone can be $110 to $390. Sterilizing-grade filter capsules run $40 to $180. Film is $3 to $8 per m2, and at 77 percent yield you pay for 1.25 m2 to ship a 0.96 m2 bag. Platinum-cured silicone tubing is $4 to $12 per meter, and drop below 150 mm adds 5 to 10 percent. Run Bag Film Yield and Tubing Cut Length Cost so scrap sits in the material line where you can see it, not hidden in a fudge factor.

Fully burdened cleanroom labor runs $45 to $75 per hour once you load gowning, breaks, and non-productive time. A build with 16 minutes of standard time is not 16 minutes of paid time. With a 1.23 gowning and overhead factor, you pay for 19.7 minutes, or roughly $18 to $25 at $55 to $75 per hour. Connector Assembly Labor and Cleanroom Labor quantify this. Traceability Workload adds a hidden 2 to 5 minutes per unit for lot capture, label reconciliation, and device history record entry that estimators routinely leave out entirely.

Gamma irradiation costs $0.15 to $0.60 per kit at pallet volume, but small lots hit a minimum tote or pallet charge of $800 to $2500 that, split across 200 kits, becomes $4 to $12 each. Gamma Dose Cost shows how packing density collapses the per-unit cost. Do not forget dose mapping and validation, a one-time $8000 to $25000 you amortize across the program. For steam or E-beam, Sterilization Load determines cycles, and each cycle carries fixed energy, labor, and biological indicator cost regardless of how many units you managed to load.

Yield is a cost multiplier, not a footnote. If rolled throughput yield is 90 percent, every good unit carries the cost of 1.11 built units, so a $200 build cost becomes $222 before overhead. Scrap Cost pinpoints where the loss happened: a kit failing final leak test carries full material plus all accumulated labor and sterilization, maybe $240, while a film reject at forming loses only $6 of film. Quote to your real first-pass yield, not the 99 percent on the validation report. A 5 point yield miss on a 500 unit order is 25 scrapped kits and thousands in lost margin.

Cleanroom overhead is real money. ISO 7 space runs $150 to $400 per square foot to build and $30 to $80 per square foot per year to operate with HVAC, gowning consumables, and monitoring. Allocate it per labor hour or per square foot occupied. A station occupying 40 sq ft at $60 per sq ft per year, running 3000 productive hours, adds about $0.80 per occupancy hour, small per unit but nonzero. Roll this into the burdened labor rate rather than a separate line so the quote stays clean and the customer sees one defensible number.

A defensible quote has three tiers: nonrecurring engineering, tooling and setup, and per-unit price at stated volume. NRE covers design, drawings, and sterilization validation, often $10000 to $40000. Setup covers first-article, line clearance, and lot documentation. Then price per unit at 3 volume breaks, since an MOQ of 50 versus 1000 can swing per-unit price 30 to 50 percent as fixed costs and gamma minimums spread. State assumptions: film yield, connector count, dose, and expected RTY. When a customer questions price, the line-item BOM and the yield factor are your defense.

Estimates go wrong in five predictable places. First, quoting net tubing length and ignoring 5 to 10 percent drop. Second, using standard time instead of gowned, burdened time, a 20 to 25 percent miss. Third, omitting traceability and device history record labor entirely. Fourth, applying the gamma pallet rate to a 150 unit lot and missing the minimum charge. Fifth, quoting at validation yield rather than production RTY. Any one of these can erase a 12 to 18 percent margin. Cross-check the quote against Scrap Cost and Cleanroom Labor before it goes out the door.

Published 2026-07-02.