Feasibility Study of Streptozotocin (STZ) Induced Cellular Changes Using Tamm Plasmon Polaritons in a One-Dimensional Photonic Crystal

Abstract

In this research, we design, simulate, and validate a label-free optical sensor that we use to monitor STZ-induced changes in neural stem cells. The basis of this sensor is the tamm plasmon polariton (TPP), which is excited at the interface of a one-dimensional photonic crystal and a thin layer of gold. In this work, we optimize the thickness of the gold layer and the measurement method by simulation based on the transfer matrix to increase the sensitivity of the sensor. After making the designed sensor, we cultured third-pass neural stem cells from the hippocampus of neonatal Wistar rats on it. After treating the cells with STZ, known to induce Alzheimer-like changes in vitro, 
the reflection spectra were recorded at selected time points (0, 17, and 30 h), illustrating the sensor’s potential for real-time monitoring of cellular responses. Finally, we compared and analyzed the simulation and experimental results. The proposed sensor, as a non-invasive,  high-sensitivity, and real-time method, can be used to monitor Alzheimer’s-like processes in laboratory conditions.