Selective Detection of HbA1c Using Surface Enhanced Resonance Raman Spectroscopy

Abstract

In the current work, we report on selective detection of HbA1c, a marker for glycemic control in diabetic patients, using surface enhanced resonance raman spectroscopy (SERRS). We found a characteristic band around 770-830 cm(-1) in the SERRS spectrum of HbA1c which was not present in the SERRS spectrum of HbA. To examine the contribution of glucosyl moiety to the characteristic SERRS band of HbA1c, we investigated SERRS spectra for nonenzymatically glycosylated HbA. We found that the SERRS spectral features are essentially identical for both HbA1c and nonenzymatically glycosylated HbA. Furthermore, addition of HbA into colloidal solution of silver nanoparticles (Ag NPs) resulted in the formation of large aggregates of Ag NPs and subsequent sedimentation. On the other hand, aggregation of Ag NPs was considerably low in the case of HbA1c. The differential effect of HbA and HbA1c on colloidal solution of Ag NPs, probably due to their difference in hydrophilicity, enabled us to separate them in a mixture. The separation was characterized by electrophoresis and SERRS analysis. Thus, colloidal solution of Ag NPs and SERRS would be a promising tool for the selective detection of HbA1c.

Biophotonics methods for functional monitoring of complications of diabetes mellitus

“…For these purposes, numerous modifications of traditional Raman spectroscopy were used, including surface-enhanced Raman spectroscopy (SERS). In a study conducted by Kiran et al [64], the possibility of using surface-enhanced resonance Raman spectroscopy (SERRS) to assess the accumulation of glycated hemoglobin, one of the most used markers for long-term glycemic control, was shown. In order to enhance the recorded Raman signal, the authors applied a solution of silver nanoparticles, after which they observed characteristic SERRS peaks in the range of 770 to 830 nm in HbA1c solution.…”

Emerging trends in optical sensing of glycemic markers for diabetes monitoring

“…Notably, Ishikawa and co-workers have exploited the surface-enfacement resonance Raman spectroscopy (SERRS) technique, which couples both surface enhancement and resonance enhancement, for sensitive, specific detection of HbA1c [33]. In this article, they used silver nanoparticles (AgNPs) of 60 nm diameter to enhance the intrinsically weak Raman signal.…”

“…The characteristic band around 770– 830 cm-1 is only present in the SERRS spectrum of HbA1c and forms the basis for the selective detection of HbA1c. {Reprinted with permission from [33]}.…”

Raman spectroscopy and PCA-SVM as a non-invasive diagnostic tool to identify and classify qualitatively glycated hemoglobin levels in vivo

“…Lin et al [7] showed that Raman spectroscopy combined with multivariate analysis (PCA-LDA) was able to distinguish the blood Hb in vitro of diabetic patients from that of healthy subjects. Due to weak signal of the plasma glucose, researches have worked with other technique, like Kiran et al [8] found a characteristic band in the SERRS (Surface Enhanced Resonance Raman Scattering) spectrum of HbA1c, which was not present in the SERRS spectrum of HbA. In this study, we applied Raman spectroscopy and PCA-SVM in vivo to identify and classify glycated hemoglobin levels in healthy population and diabetic patients.…”