Tear fluid biomarker analysis: toward standardized tear collection
The SMTube Approach
SMTube is a general medical device developed for tear assessment in dry eye clinical practice. A unique device structure and a 5-second-per-eye procedure allow rapid absorption of tears. The minimally invasive collection process suppresses reflex tearing and contributes to the standardization of tear collection.
Tear collection time: 5 seconds per eye
No anesthesia required
Basal tear collection
Suppression of reflex tearing through a rapid, simple, minimally invasive procedure
28 original papers (as of September 1, 2026)
Peer-reviewed publications using SMTube (20 human, 8 animal)
Comparison of tear collection methods (summary)
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| Criterion | Glass Capillary Tubes | Schirmer Strips | SMTube |
|---|---|---|---|
| Reported use | 45%[1] | 25%[1] | Novel method |
| Speed and ease of use | Time-consuming; skill required[1, 2] | 5-minute placement; simple[1, 2] | 5-second contact; rapid and simple[3] |
| Effect on tear composition | Minimally invasive (avoids reflex tearing)[1] | Reflex tearing due to irritation[2] | Minimally invasive (avoids reflex tearing)[3, 4, 5] |
| Quantification and standardization | Depends on operator skill[2] | Varies between manufacturers[1, 2] | Single manufacturer; controlled manufacturing process |
What is SMTube?
Structure, procedure, clinical study reports, and publication list for SMTube.
Comparison of collection methods for tear fluid biomarkers
Comparison of tear collection methods used in tear fluid biomarker research, and the methods reported in each research area.
References
- Gijs M, van de Sande N, Bonnet C, et al. A comprehensive scoping review of methodological approaches and clinical applications of tear fluid biomarkers. Prog Retin Eye Res. 2025;106:101338. doi:10.1016/j.preteyeres.2025.101338
- Schmeetz J, Hagan S, van de Sande N, et al. A practical starting guide to tear fluid biobanking. Adv Ophthalmol Pract Res. 2026;6(3):281-290. doi:10.1016/j.aopr.2026.04.001
- Shinzawa M, Dogru M, Miyasaka K, Shimazaki J, Sekiryu T. Application of CASIA SS-1000 Optical Coherence Tomography Tear Meniscus Imaging in Testing the Efficacy of New Strip Meniscometry in Dry Eye Diagnosis. Eye Contact Lens. 2018;44 Suppl 1:S44-S49. doi:10.1097/ICL.0000000000000312
- Dogru M, Ishida K, Matsumoto Y, et al. Strip meniscometry: a new and simple method of tear meniscus evaluation. Invest Ophthalmol Vis Sci. 2006;47(5):1895-1901. doi:10.1167/iovs.05-0802
- Ibrahim OM, Dogru M, Ward SK, et al. The efficacy, sensitivity, and specificity of strip meniscometry in conjunction with tear function tests in the assessment of tear meniscus. Invest Ophthalmol Vis Sci. 2011;52(5):2194-2198. doi:10.1167/iovs.10-5986