According to the International Diabetes Federation, the worldwide diabetes prevalence was 10,5% (537 million people) in 2021. The Near Infrared (NIR) Spectroscopy is raised to be a promising method for painless, reliable non-invasive glucose continuous monitoring. The aim of this work is the characterization of a multispectral image sensor to predict non-invasively the concentration of biological substances. The photosensor exploited is the STMicroelectronics VD56G3 (aka FOXY), enhanced with a filters array (64 total wavelengths) in the NIR range 780-1062 nm. First, the cross-channel interference within the NIR filters array is observed. This optical phenomenon leads to the distortion of the prototype spectral sensitivity and negatively affects the final prediction.