A novel luminescent temperature sensor using ruthenium(II)-tris(2,2´-bipyridyl) ([Ru(bpy)3]2+) incorporated into chitosan polymer matrix was developed. The sensor exhibits completely reversible and stable luminescent response (λexc = 455 nm, λem = 605 nm), strong temperature sensitivity (–2.0 %/°C), significant luminescence intensity decrease (~10x) in the range of 25–75°C, and stable construction. Ruthenium(II) complex oxygen sensitivity was avoided by the use of matrix (chitosan) with low oxygen permeability coefficient. In the absence of oxygen the sensor shows a little higher accuracy and stability of luminescence response than under oxygen conditions. Moreover, this sensor, due to biocompatibility of the used ingredients and the emission in the red VIS-region, which is transparent for tissues, is promising for the use in biological applications.
