Tear-fluid biopsy

01Overview and value chain

Markers: [EC: IVDR 2017/746 | OECD: Biotech-health | Regulator: FDA (USA), EMA (European Union), NMPA (China)]

Tear-fluid biopsy tests a microliter-scale tear sample at the point of care for dry eye disease, ocular allergy and inflammatory biomarkers, offering a diagnostic window that avoids blood draw or invasive tissue sampling entirely. Trukera Medical’s tear osmolarity system (built on the TearLab platform lineage) measures tear-film osmolarity as the reference biomarker for dry eye disease severity, with its dynamic temperature-compensation technology documented in a dedicated patent filing and distributed in some markets through a Topcon Healthcare partnership. Lacrisciences’ LacryDx test (developed by Advanced Tear Diagnostics) measures tear IgE to diagnose allergic conjunctivitis at the point of care. QuidelOrtho’s InflammaDry test detects elevated MMP-9, an inflammatory marker associated with dry eye disease, though a 2026 industry report flagged a supply disruption affecting at least one distribution channel for the product. In France, DiagnosTear’s TearX platform recently reported interim clinical study results showing excellent correlation between its Red Eye test and quantitative ELISA testing, alongside French regulatory approval and a new clinical study initiated with Alyatec.

The key directions of tear-fluid biopsy are:

1. Tear osmolarity testing (Tear Osmolarity Testing): measuring the salt concentration of tear film as the reference biomarker for dry eye disease severity and treatment monitoring — Trukera Medical.
2. Tear IgE allergy testing (Tear IgE Allergy Testing): point-of-care immunoglobulin E measurement in tears to diagnose allergic conjunctivitis without a blood draw — Lacrisciences’ LacryDx.
3. Tear inflammatory biomarker testing (Tear Inflammatory Biomarker Testing): lateral-flow detection of inflammatory markers such as MMP-9 associated with dry eye disease — QuidelOrtho’s InflammaDry.
4. Point-of-care tear ELISA-correlated testing (Point-of-Care Tear ELISA Testing): rapid tear tests validated against quantitative laboratory ELISA reference methods — DiagnosTear’s TearX.

Sectoral value chain

[tear sample collection] ──> [point-of-care analyzer reading] ──> [biomarker quantification]
                                                    │
                                       (clinical report / diagnosis)
                                                    │
                                                    ▼
[treatment decision (dry eye/allergy/inflammation)] <─── [regulatory clearance] <─────┘

Value chain levels

Cross-cutting technologies of the sector:

• Osmolarity measurement (Tear Osmolarity Testing): electrical impedance or freezing-point-depression methods quantify tear-film salt concentration, the established reference biomarker for dry eye severity.
• Point-of-care immunoassay (Tear IgE Allergy Testing / Tear Inflammatory Biomarker Testing): lateral-flow or microfluidic immunoassay chemistry detects specific proteins (IgE, MMP-9) in a microliter tear sample without a central laboratory.
• ELISA-correlated rapid testing (Point-of-Care Tear ELISA Testing): point-of-care tear tests validated directly against quantitative ELISA reference methods, as DiagnosTear’s interim clinical data demonstrates for its Red Eye test.

02US

The US anchors the deepest bench of tear-fluid diagnostic companies, spanning osmolarity, allergy and inflammatory-marker testing.

TearLab/Trukera, LacryDx, InflammaDry, FDA

• Trukera Medical: its tear osmolarity system measures tear-film osmolarity as the reference biomarker for dry eye disease severity, with dynamic temperature-compensation technology documented in a dedicated patent and distributed in some markets through a Topcon Healthcare partnership.
• Lacrisciences: its LacryDx test (developed by Advanced Tear Diagnostics) measures tear IgE to diagnose allergic conjunctivitis at the point of care without a blood draw.
• QuidelOrtho: its InflammaDry test detects elevated MMP-9, an inflammatory marker associated with dry eye disease, though a 2026 industry report flagged a supply disruption affecting at least one distribution channel for the product.
• FDA framework: tear-fluid point-of-care tests clear the FDA via 510(k) review as in-vitro diagnostic devices, with each biomarker claim (osmolarity, IgE, MMP-9) reviewed against its own clinical-validation evidence.

03CN

No dedicated Chinese tear-fluid diagnostic company cleared source confirmation as of 2026; the field’s coverage in Chinese sources centers on general dry-eye-disease market analysis rather than a specific commercial tear-diagnostic originator.

research/market gap, NMPA pathway

• Market analysis focus: Chinese industry reporting on dry eye diagnostics in this period covers the broader dry-eye-disease market rather than a tear-fluid-specific diagnostic platform.
• NMPA pathway: any tear-fluid diagnostic device reaching Chinese clinical use would register with NMPA as an in-vitro diagnostic medical device, following the same point-of-care device pathway used for other ophthalmic diagnostics.

04EU

France anchors Europe’s tear-fluid diagnostics through DiagnosTear, whose TearX platform recently cleared French regulatory approval alongside new clinical validation data.

TearX, DiagnosTear, IVDR

• DiagnosTear: its TearX platform recently reported interim clinical study results showing excellent correlation between its Red Eye test and quantitative ELISA testing, alongside French regulatory approval and a new clinical study initiated with Alyatec.
• IVDR framework: tear-fluid diagnostic devices sold in the EU require conformity assessment and CE marking under the In Vitro Diagnostic Regulation (IVDR 2017/746), the bar DiagnosTear’s French approval reflects.

05Leading companies and research institutes

06Tech stack and innovations

The stack applies distinct point-of-care chemistries — osmolarity measurement, lateral-flow immunoassay, and ELISA-correlated rapid testing — to the same microliter tear sample to reach different diagnostic endpoints.

1. Tear osmolarity measurement (Tear Osmolarity Testing):
   • Trukera Medical’s system quantifies tear-film salt concentration with dynamic temperature compensation, the established quantitative reference for dry eye disease severity and treatment monitoring.
2. Point-of-care IgE and inflammatory-marker immunoassay (Tear IgE Allergy Testing / Tear Inflammatory Biomarker Testing):
   • Lacrisciences’ LacryDx detects tear IgE for allergic conjunctivitis, and QuidelOrtho’s InflammaDry detects elevated MMP-9 for dry eye inflammation, both using lateral-flow or microfluidic immunoassay chemistry that returns a result at the point of care.
3. ELISA-correlated rapid diagnostics (Point-of-Care Tear ELISA Testing):
   • DiagnosTear’s TearX Red Eye test is validated directly against quantitative ELISA reference methods, with interim 2026 clinical data reporting excellent correlation between the rapid test and the laboratory gold standard.
4. Regulatory-cleared point-of-care ophthalmic diagnostics:
   • Each platform’s biomarker claim clears its own regulatory review (FDA 510(k) or EU IVDR), reflecting the category’s maturity as an established, cleared point-of-care diagnostic tier rather than a research-stage technology.

07Value chains and production pipelines

Industrial pipeline of a tear-fluid diagnostic test (FDA 510(k) / EU IVDR 2017/746)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Tear sample collection │ ───> │ 2. Point-of-care analyzer │
│                            │      │    reading                  │
└───────────────────────────┘      └───────────────────────────┘
                                                   │
                                                   ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Clinical report/       │ <─── │ 3. Biomarker               │
│    diagnosis                │      │    quantification            │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Regulatory clearance   │ ───> │ 6. Treatment decision     │
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Tear sample collection

A microliter-scale tear sample is collected via microcapillary tube or test strip at the point of care, an entirely non-invasive procedure taking seconds.

Stage 2: Point-of-care analyzer reading

A benchtop or handheld device reads the sample — measuring electrical impedance for osmolarity (Trukera Medical) or running a lateral-flow immunoassay for IgE or MMP-9 (Lacrisciences, QuidelOrtho) — without sending the sample to a central laboratory.

Stage 3: Biomarker quantification

The raw analyzer signal is converted into a quantitative or semi-quantitative biomarker value, such as an osmolarity reading in mOsm/L or a positive/negative IgE or MMP-9 call.

Stage 4: Clinical report and diagnosis

The biomarker value is interpreted against an established reference threshold to reach a diagnosis — dry eye disease severity, allergic conjunctivitis, or inflammatory status — as DiagnosTear’s TearX correlates directly against ELISA reference results.

Stage 5: Regulatory clearance

The point-of-care device and its specific biomarker claim clear FDA 510(k) review or EU IVDR conformity assessment and CE marking, with DiagnosTear’s French approval reflecting the same regulatory bar its US counterparts have already cleared.

Stage 6: Treatment decision

The eye-care provider uses the diagnosis to select dry eye management, anti-allergy treatment, or anti-inflammatory therapy, closing the loop from a non-invasive tear sample to a targeted clinical intervention.