Detecting glucose in a cell culture medium by surface-enhanced Raman scattering on InGaN quantum wells

Cell cultivation is a multi-billion dollar industry. The industry is currently in great need of a glucose-monitoring tool to maximize the yield of biological products. However, detecting glucose in a cell culture medium is no easy task. This is because the medium contains complex cell nutrients, from which the interfering noises make it extremely difficult to extract reliable glucose signals. We address the issue by surface-enhanced Raman spectroscopy (SERS) built with InGaN quantum wells, delivering concentration-dependent glucose signals from the noisy medium. The breakthrough is made by the quantum-confined charges whose oscillating frequency matches the plasmonic resonance desired for SERS.