Introduction
The eQUANT system is a compact benchtop sample preparation device that utilizes proprietary electrochemical biosensor technology to quantify microorganisms in suspension by measuring changes in oxidation-reduction potential (ORP) associated with microbial growth. In its current FDA-cleared IVD configuration, eQUANTrequires prior identification of the Gram-negative organism recovered from positive blood culture in order to generate a standardized bacterial inoculum equivalent to a 0.5 McFarland (eMcFarland), which serves as input for downstream disk diffusion antibiotic susceptibility testing (AST).
Here, we present proof-of-concept data for a next-generation research use only (RUO) eQUANT system that does not require prior species identification to generate a standardized bacterial suspension within a target concentration range of 1–2 × 10⁸ CFU/mL (±0.6 log).
In contrast to the current IVD eQUANT system, which aerates only aerobic organism samples and applies species-specific algorithms to generate a 0.5 McFarland equivalent suspension, this next-generation system utilizes aeration across all organism types and applies a universal algorithm forgeneration of a standardized output sample. By developing the ID agnostic eQUANT RUO system, we aim to not only simplify its workflow but also to expand controlled microorganism growth capabilities for a broader range of downstream applications beyond antibiotic susceptibility testing, including MALDI-TOF ID.
