Rapid and real-time diagnosis of hypoalbuminemia using an extraordinary optical transmission biosensor

A hypoalbuminemia diagnosis kit, based on an extraordinary optical transmission sensor, for accurate and fast measurements of albumin concentrations in human serum was demonstrated. First, using nanohole arrays, the sensitivity of the sensor was confirmed to be approximately 460 nm/RIU by theoretical simulations and using standard solutions with specific refractive indices. In the preliminary study of albumin measurements, non-labeled detection of a difference in albumin concentration of approximately 10 mg/ml was achieved with a spectral peak shift of 0.8972 nm and proved to be capable of diagnosing hypoalbuminemia without a surface modification process. Additionally, we successfully classified 100 samples with different concentrations into normal and hypoalbuminemia groups with a probability greater than 98%. According to the results, the hypoalbuminemia diagnosis kit has a potential to be practically employed for real-time, preclinical, label-free diagnosis with integration of advanced microfluidics and miniaturized optics.