Abstract: The present invention provides a biosensing system including a microfluidic-based biosensor designed for both point-of-care testing and a home-based assessment. A method for distinguishing a metastatic sample from a non-metastatic sample in-situ based on an observation of relative distribution of organisms in a biosensor of the present system in response to different test samples through a portable imaging device or an imaging module integrated into a smartphone or mobile device is also provided. Chemotactic preference of the organisms to a sample is quantified by using Raman spectroscopy to generate a profile of target analytes for determination of metastatic status and potential in a particular sample.