That depends on the PDF viewer software you use. If your PDF viewer allows dragging a page then there ought to be a way to accept it in DropMaster. My advice is to build the FormatViewer demo that comes with DropMaster and see what happens if you attempt a drop into it. FormatViewer should list every data format present in a drag and it is the primary tool you need for figuring out how to use a new/non-standard drop source.
Hope this helps.