Puritan PurSafe Plus Collection and Transport System

The Puritan PurSafe Plus Collection and Transport System is a single-use device for collecting, inactivating, and preserving human upper respiratory specimens suspected of containing SARS-CoV-2. It consists of a sterile polyester flock swab in a peel pouch and a polypropylene vial containing 1 mL of PurSafe Plus buffer that stabilizes and inactivates the virus during transport and storage at temperatures between 2-4°C and 25-30°C.

The test device uses a higher pH buffer (8.3 ± 0.2) compared to the predicate's pH 5.0-7.0 and extends the storage temperature range to include refrigerated conditions (4-30°C) versus the predicate's ambient-only storage (20-25°C). Both devices share identical physical components: polypropylene conical vials, plastic swab shafts, flock swab tips, and 24-month shelf life. The medium formulation is similar, containing inactivation buffer, salts, pH buffering agents, and molecular-grade water.

Not stated in this summary.

Substantial equivalence is established through comparative performance testing demonstrating functional equivalence to the predicate device. Limit of Detection studies showed both devices achieved 64 genome copies/mL detection using the Cepheid GeneXpert IV system with no adverse effects. Stability studies across multiple lots and temperatures (4°C and 30°C for 28 days) demonstrated equivalent RNA preservation with mean Ct values within 3 units of baseline. Inactivation studies confirmed the PurSafe Plus buffer successfully inactivated SARS-CoV-2 virus. The broader storage temperature range represents an expansion of use rather than a fundamental difference in intended purpose or mechanism, as both devices preserve specimens for use with molecular diagnostics.