Yes. However, to ensure the long-term reliability of your documents, it is recommended that you digitally sign in PDF/A format. To do so, the PDF/A-3 format includes a feature to embed a file of any type within the PDF.
However, if the organization requires another format, such as a .xml files, you can instead sign by “encapsulation”. Encapsulation places the original document in an “envelope” which can then be digitally signed. The newly signed, encapsulated document bears the “.p7m”* file extension.
For example, XML data signed by encapsulation will turn out a file called name_of_file.xml.p7m. To sign by encapsulation, select the file in Windows Explorer, then right-click and select Digitally Sign File… *By using the standard PKCS#7 format.