Intro to Chromatographic Techniques
Start with the big picture
Separation occurs because analytes interact differently with the stationary and mobile phases, so they travel at different rates. Resolution is influenced by selectivity, column efficiency, and retention, with operating conditions and column choice affecting performance. HPLC moves a liquid phase through a packed column and offers several separation modes and detector options. GC carries volatile, thermally stable or derivatized samples through a coated capillary column, with the oven program and carrier-gas flow among its key variables. TLC separates compounds on a thin sorbent layer as solvent rises by capillarity; Rf values and visualization methods help assess the separated spots. Each technique suits different analytical needs: TLC offers rapid, parallel, low-cost analysis, while HPLC and GC provide greater resolution and sensitivity. The full topic also addresses sample preparation, system suitability, validation, and pharmaceutical applications.
What you'll learn
- Explain how differential partitioning between stationary and mobile phases separates analytes.
- Describe how selectivity, efficiency, and retention contribute to chromatographic resolution.
- Compare HPLC, GC, and TLC by principle, sample requirements, and instrumentation.
- Identify common detection and visualization approaches used with HPLC, GC, and TLC.
- Recognize operating variables and practical limitations relevant to each technique.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
