Integrated evanescent wave spectral sensing device

An integrated spectral sensing device, comprising:

• a first substrate comprising an attenuated total internal reflection (ATR) element, a microfluidic channel, and a channel interface corresponding to a boundary between the ATR element and the microfluidic channel formed therein, the channel interface being formed at sidewalls of the ATR element, the ATR element configured to receive input light and to produce output light based on total internal reflection of the input light at the channel interface, the output light being attenuated by an evanescent wave produced by a sample contained within the microfluidic channel based on the total internal reflection of the input light;
• a spectrometer configured to produce an interference beam, the interference beam corresponding to the input light or being produced based on the output light;
• and
• a detector configured to detect a spectrum of the interference beam or the output light.