Milford-based biotech company Waters Corp. will merge with Becton, Dickinson and Co.’s biosciences an diagnostic solutions unit in a $17.5 billion deal.

Lab equipment maker Waters Corp on Monday said it will buy a bioscience and diagnostics unit spun off from medtech provider Becton Dickinson in a stock-and-cash transaction valued at $17.5 billion, expanding its scale in clinical and diagnostic applications.

A deal for Becton Dickinson’s biosciences and diagnostic solutions unit puts Waters Corp. in a greater position to compete with larger life-science companies, but integration risks can’t be discounted,