Portable Fingernail Test Shows Promise for Early Diabetes Screening

Portable instrumentation is becoming more widely used in clinical analysis because of its ability to rapidly detect disease. A recent study examined how portable instrumentation could be applied in the detection of diabetes. This study, which was published in the Journal of Diabetes Science and Technology, used a Glyconics-DS system, which was equipped with a near-infrared (NIR) spectrometer, to analyze fingernail samples to screen for diabetes.

What is diabetes, and how is it diagnosed?

Diagnosing diabetes can be done through several methods. These include the A1C test, the fasting plasma glucose (FPG) test, the oral glucose tolerance test (OGTT), and the Random Plasma Glucose test (2). However, these methods can be costly, inconvenient, and resource-intensive, which means that there are barriers in place for these methods to be used in low-income and underserved regions. As a result, there is a push for more affordable methods to test for diabetes (1). The objective has been to develop methods that can allow for mass screening without the logistical barriers of invasive procedures.

Senior woman hands using lancet on finger at home to check blood sugar level, glucometer and sugar cubes on wooden table close up, diabetes concept, elderly health care, sunny morning. | Image Credit: © zakalinka -stock.adobe.com

What is the Glyconics-DS system, and how does it improve on traditional methods?

The Glyconics-DS system consists of a miniaturized near-infrared (NIR) spectrometer, a cradle, and analytical software that works by examining glycated keratin in fingernails (1). The idea behind the system is that because glucose leaves chemical traces in nail proteins, these can be detected using full-spectrum NIR spectroscopy.

The research pooled data from two independent pilot studies, ANODE01 and ANODE02, which were conducted in two distinct health care environments, including a specialized diabetes research center and a primary care clinic (1). Together, the studies included 200 participants, evenly divided between individuals with and without diabetes. More than 12,000 spectral readings were collected, with 60 repeated scans of fingernails from each participant (1).

What were the results of the study?

The results demonstrated strong specificity in identifying those without diabetes, reaching 92.9% (95% CI: 88.5–97.4) (1). The researchers also observed that sensitivity was more modest at 34.2% (95% CI: 23.4–45.1) (1). Overall concordance with HbA1c-based diagnoses stood at 71.5% (1). Importantly, the study reported no adverse events, and the method’s reproducibility was not significantly influenced by factors such as age, smoking status, hand dominance, or pre-existing health conditions (1).

As a result, the Glyconics-DS system demonstrated numerous benefits for diabetes diagnosis. First, it minimized false positives. Considering that part of the issue is low-income areas having limited or no access to quality health care, developing tools that can operate accurately would help accelerate providing care to patients. Second, this system is sustainable (1). It requires no consumables, making it both cost-effective and environmentally friendly. Its portability and rapid results position it as a potential tool for community-level screening and early detection initiatives (1).

What were the limitations of the study?

The researchers acknowledged several limitations of their study. For one, portable technology, like the one presented in this study, was not workable for individuals with nail discoloration, abnormalities, or other visible changes, which can interfere with spectral accuracy (1). Nonetheless, as long as at least one healthy nail is available, a reliable assessment remains possible. Another challenge is the system’s lower sensitivity in detecting early-stage diabetes, meaning additional refinements are needed to improve detection among undiagnosed individuals.

Looking ahead, the researchers plan to expand testing through the upcoming ANODE03 study, which will target populations with unknown diabetes risk. Unlike controlled clinical cohorts, this real-world trial aims to evaluate the device’s sensitivity in everyday screening scenarios (1).

Despite these limitations, the pooled analysis provides encouraging evidence that NIR spectroscopy of fingernails could play a significant role in diabetes management. By offering an affordable, non-invasive, and reusable option, the Glyconics-DS system may reduce health care disparities and support timely interventions before complications arise (1).

References

1. Choudhary, P.; Paldanius, P. M.; Salter, J. E.; et al. Use of a Miniaturized Near-Infrared Spectroscopy Device for Type 2 Diabetes Mellitus Screening: Pooled Analysis of the Pilot ANODE01 and ANODE02 Studies. J. Diabet. Sci. Technol. 2025, ASAP. DOI: 10.1177/19322968251331069
2. American Diabetes Association, Understanding Diabetes Diagnosis. Diabetes.org. Available at: https://diabetes.org/about-diabetes/diagnosis (accessed 2025-09-23).