We have recently developed a new method for indirect detection of 17O. This method uses scalar coupling between 1H and 17O in H217O. Scalar coupling between 17O, a spin 5/2 nucleus, and 1H in 1H217O is about 92 Hz. At neutral pH, protons in H217O exchange with that in H216O. This exchange and the T1 processes of 17O modulate the scalar coupling. This modulated scalar coupling causes proton line broadening in H217O. The present method exploits the properties of 1H217O in the presence of a spin-locking radiofrequency field. We have demonstrated the strong dependence of T1r relaxation time of H217O on the strength of spin-locking field. This dependence of T1r on the strength of spin-locking field is known as T1r dispersion of the sample. This method has potential application in the study of oxidative phosphorylation and blood flow. We have implemented this method in vivo on mouse brain. Mouse brain was imaged with T1r sequence following injection of known amount of H217O. The ratio image obtained from two T1r images has been used to calculate the image intensity. The 17O concentration calculated is in excellent agreement with that of actual. Further in vivo studies are in progress.