A stable covalent binding technique for lipase enzyme immobilization on an long period fiber grating is reported for the detection of triacylglycerides.

The enzyme immobilization is confirmed by Scanning Electron Microscopy (SEM) and Raman Spectroscopy.

The sensor is based on the shift in resonance wavelength of the LPG transmission spectrum due to the interaction of triacylglycerides with the enzyme.

Interaction between the bio-molecules and the long period grating surface is also modeled theoretically using a four layer model for the LPG fiber with the bio-recognition layer and the results obtained are consistent with experimentally obtained results.