Hey
The eligibility criteria for M. Tech nanotechnology is b. Tech passed with a minimum percentage of 50% . So it doesn't matter which subject you are pursuing B. Techwith , you are equally eligible for M. Tech nanotechnology. But  its better if you pursue b. Tech in some technical field like EEE or IT  for better understanding of technology.
Hope it helps!

Dear Aspirant,

If you wish to pursue M. Tech. in Nanotechnology in your higher study,

then you may complete your Btech. in any one of the following

Material science,

Mechanical,

Biomedical,

Chemical,

Biotechnology ,

Electronics and Computer Science.

All the best!