A bio-thermochemical microbolometer with immobilized intact liposome on sensor solid surface

We have developed a scheme of bio-thermochemical microbolometer with immobilized intact liposome on sensor solid surface. A liposome of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) was confirmed to be deposited intact by X-ray diffraction (XRD) and AFM analysis on a Pt film that is used as resistive bolometer material. By using a fabricated surface micromachined thermal cavity structure beneath the Pt resistor film with the immobilized intact liposome, thermochemical reactions of DPPC on phase transition among gel, ripple and fluid phases have been successfully detected. It is also found from analysis of fluorescence polarization that endothermic reaction especially at around 40 °C (phase change from ripple to fluid) corresponds to the change in mobility of phospholipid molecule. As a result we believe that the developed scheme of the microbolometer is effective for detecting thermochemical reaction of biochemical molecules that interact with the liposome.