Multiscale flaked silver SERS-substrate for glycated human albumin biosensing

Area of Science:

• Nanomaterials
• Biosensing
• Analytical Chemistry

Background:

• Glycated albumin (GA) is a significant biomarker for diabetes monitoring.
• Existing biosensing methods for GA can be complex and time-consuming.
• Development of sensitive and selective SERS substrates is crucial for efficient GA detection.

Purpose of the Study:

• To develop and evaluate a multiscale flaked silver SERS-substrate (MFSS) for glycated albumin (GA) biosensing.
• To investigate the substrate's performance in detecting GA in human plasma samples.
• To enable a quantitative, one-step biosensing method for GA.

Main Methods:

• Fabrication of a multiscale silver SERS-substrate with size dispersion from 50 nm to 2 μm.
• Surface modification of the SERS-substrate with 4-mercaptophenylboronic acid (4-mPBA) for GA selectivity.
• Utilized surface-enhanced Raman scattering (SERS) spectroscopy combined with Principal Component Analysis (PCA) and Partial Least Squares Regression (PLS-R) for spectral analysis and quantification.

Main Results:

• The MFSS demonstrated effective SERS properties due to 'hot spots' and localized surface plasmons.
• The 4-mPBA modification enabled selective detection of GA through interactions with cis-diol groups.
• PCA and PLS-R successfully discriminated spectra and allowed for calibration curve construction and GA quantification in human plasma.

Conclusions:

• The multiscale flaked silver SERS-substrate modified with 4-mPBA is a highly effective platform for GA biosensing.
• This method allows for quantitative, one-step detection of GA in small volumes (15 μl) of human plasma.
• The developed SERS substrate offers a promising approach for clinical diagnostics and monitoring of diabetes.