ZZBio Technology (Shanghai) Co., Ltd. officially releases its new-generation high-sensitivity digital PCR chip. The chip raises single-chip reaction capacity to 30μL, paired with a 10× concentrated dPCR Master Mix, enabling nucleic acid input of up to 26μL per sample (about 86% of the reaction volume) — directly addressing the sensitivity bottleneck in low-abundance scenarios such as liquid biopsy, MRD monitoring and ultra-low-load pathogen detection.
1. Technical Background: Sample Input Determines the Sensitivity Ceiling
Digital PCR partitions a reaction into thousands of independent micro-reactions and achieves absolute quantification without standard curves via Poisson statistics. Its detection limit and precision are directly governed by the countable target copies per reaction — the more template input, the more reliable detection and quantification of low-abundance samples.
However, reaction volume allocation has long limited sample input: mainstream chips offer 9–25μL capacity with 2× concentrated Mix; after buffer, polymerase, dNTP and primers/probes, nucleic acid input is typically below 10μL. For low-concentration samples such as liquid biopsy, targets are already scarce after extraction — insufficient input yields few positive events and limits detection rate and reproducibility in the low-abundance range.
2. New Product Specifications: Dual Boost in Capacity and Concentration
Higher sample input directly determines the countable target copies per test: LOD pushes lower, precision and inter-run reproducibility in the low-abundance range improve together; ample template also reduces reliance on pre-amplification, avoiding bias and contamination it may introduce.
| Item | Mainstream dPCR Chips | New ZZBio High-Sensitivity Chip |
|---|---|---|
| Reaction capacity | 9–25μL | 30μL |
| Mix concentration | 2× | 10× |
| Max nucleic acid input | <10μL | 26μL |
| Sample volume ratio | ≤40% | ~86% |
3. Application Scenarios: Six Low-Abundance Directions
| Scenario | Pain Point | Value of High Sample Input |
|---|---|---|
| 1. Oncology liquid biopsy (low-frequency mutation & companion diagnostics) | Plasma ctDNA mutation abundance as low as 0.1%–0.01% | Far more countable mutant copies — more reliable detection of EGFR driver mutations, T790M resistance and rare variants across gene panels |
| 2. MRD monitoring | Post-surgery ctDNA signals appear 3–10 months before imaging relapse, at extremely low abundance | More stable positive/negative calling; smoother, comparable copy-number trends over time; reduced false negatives/positives |
| 3. Early screening & cfDNA methylation | Bisulfite conversion degrades DNA | Partially compensates conversion loss, letting trace methylated cfDNA enter enough micro-reactions to support ultra-low-abundance signals in screening panels |
| 4. Low-load pathogens & borderline viral loads | Low-volume samples (CSF, synovial fluid); viral load below qPCR LOQ | Raises detection probability — borderline samples shift from "unquantifiable" to "detectable and quantifiable" |
| 5. Non-invasive transplant rejection monitoring (dd-cfDNA) | Donor-derived cfDNA fraction often 0.1%–1% | High input plus absolute quantification significantly stabilizes rare-target detection for early non-invasive rejection alerts |
| 6. Research & precious micro-samples | Microdissection and biopsy samples are precious; rare events such as gene-editing validation and CNV | "Less sample, no less data" — richer statistics per experiment, fewer repeat samplings |
4. Open Platform: Bringing High-Sensitivity Specifications to Industry Partners
The new chip continues ZZBio's platform route of multi-specification microchamber chips and an open ecosystem: it works with ZZBio's own Master Mix and kits, and also supports IVD companies developing high-sensitivity assays for their own panels on the open platform.
For IVD partners building liquid-biopsy companion diagnostics, MRD monitoring or early-screening kits, the larger sample-input specification leaves more headroom and differentiation for their sensitivity design — an opening of capability toward clinical and industry partners, and another step of the "making digital PCR accessible" vision.
About ZZBio
Founded in 2016, ZZBio Technology (Shanghai) Co., Ltd. is a representative Chinese chip-based digital PCR company with in-house capabilities across micro-nano fabrication, precision instruments, imaging algorithms and biological reagents. Committed to its open-platform strategy, ZZBio's products serve oncology research, pathogen detection, gene therapy quality control, reference material calibration and liquid biopsy — making precise, accessible digital PCR reach more laboratories.