There are several reputed colleges in Tamil Nadu that offer B.Tech programs in Microbiology or related fields.

Here are some of the:

1. Anna University, Chennai
2. SRM Institute of science and Technology, Chennai
3. Vellore Institute of Technology, vellore
4. SASTRA Deemed University
5. Bharath Institute of Higher Education and Research, Chennai
6. Vel Tech Institute of Science and Technology
7. Sri Ramachandra Institute of Higher Education and Research.

Click on the below link to know more about the best colleges for B.Tech in Microbiology,  Tamil Nadu.

https://medicine.careers360.com/colleges/list-of-microbiology-and-virology-colleges-in-tamil-nadu