Label free detection of analytes

The present invention provides a method for label free detection of analytes in a sample, wherein the analytes may be selected from the group of micro-organisms,macromolecules, and small molecules. The present invention also provides a system for label free detection of analytes in a sample comprising a flow cell which houses fiber optic probe sensor immobilized with plurality of receptors for detection of said analytes and wherein the detection is based on the measurement of optical property of the said analyte