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A new material applied in liquid-core waveguides made of polydimethysiloxane (PDMS) is reported. The microfluidic PDMS chips were moulded by a silicon wafer with a master pattern of photoresist SU-8. This new photopolymer material of Norland Optical Adhesive 89 (NOA 89) provides an optical index of refraction (n=1.51) higher than those of PDMS (n=1.41) and air (n=1), thereby significantly generating a total internal reflection through the fluidic channels and solidified structures. With three distinct geometries, the optical propagation losses of infrared light with wavelengths ranging from 1500-1550 nm were found to be =3.5=dB/cm (straight-line shape), =8.4=dB/cm (circular-bend shape) and =13.2=dB/cm (rectangular-bend shape), respectively.