Hi Muhammad,

I am afraid there is not any generic/convenient technique to monitor wettability by time-domain NMR: it will depend on the type of rocks and fluids. However, there has been some interest in developing such methods. I would recommend going to SPWLA web-page and search for "NMR" and "Wettability", or just search for "NMR wettability" in Google Scholar... GIT provides a method for measuring "wettability index": Wettability - Green Imaging Technologies NMR Wettability Index

I hope it will help to find the directions for your search.