PHD Discussions Logo

Ask, Learn and Accelerate in your PhD Research

Question Icon Post Your Answer

Question Icon

2 years ago in Analytical Chemistry , Chemistry By Ramesh

What does the term HPLC-grade water mean in analytical chemistry?

In our lab, we're standardizing methods for trace analysis, and the purity of solvents is paramount. I've seen "HPLC-grade water" listed as a requirement in numerous protocols, but vendors' specifications seem to vary. I'm asking to understand the definitive criteria that distinguish this grade and why it's non-negotiable for high-performance separations.

All Answers (1 Answers In All)

By Mayur Desai Answered 1 year ago

In practice, HPLC-grade water isn't just "very pure" water; it's a specification designed to protect your column and detector. I've seen methods ruined by using water that wasn't truly HPLC-grade, introducing ghost peaks and high baseline noise. It specifically means water treated to have ultra-low UV absorbance, minimal organic contaminants, and often a defined resistivity. I would recommend always sourcing it from a reputable supplier who provides a detailed certificate of analysis. Never assume in-house purification systems, like Millipore units, meet this grade without validation for your specific sensitive application.

Your Answer