Hi, elotus.
It sounds like you have a few different options.
If you wanted to become certified in BizTalk 2010 and earn the MCTS: BizTalk 2010 certification title, you could take the 70-595 exam:
http://www.microsoft.com/learning/en-us/exam-70-595.aspx
However, if you are more interested in becoming certified in C# (possibly earning your MCSD certification), you can pass exam 70-483 which gives you a
Specialist: Programming C# title. Here it is:
http://www.microsoft.com/learning/en-us/exam-70-483.aspx
Ultimately, if your goal is to earn the older MCPD (VS 2010) or the newer MCSD (VS 2012), you can aim for one of these specialized version of these titles (ASP.NET, Windows, etc.) Learn more about the required exams here:
NOTE: The MCPD titles will remain on your transcript for several years until eventually be marked
Legacy while the newer MCSD certifications require you to recertify every two (2) years from the date you pass the final required exam. Otherwise, it will be marked as
Inactive. Learn more about recertification here:
http://www.microsoft.com/learning/en-us/certification-exam-policies.aspx#recertification
By the way - check out the free exam-specific training from Microsoft Virtual Academy here:
http://www.microsoftvirtualacademy.com
Let me know if you have any other questions.
Good luck!
Best wishes, Davin Mickelson