C18 Column: The Gold Standard in HPLC Separations
Introduction to C18 Columns The C18 column , also known as an octadecylsilane (ODS) column , is the most commonly used reversed-phase column in High Performance Liquid Chromatography (HPLC). It features silica particles bonded with octadecyl (C18) hydrocarbon chains, offering excellent non-polar interactions for a wide range of analytes. When it comes to routine or complex chromatographic separations, the C18 column in HPLC is often the first choice across pharmaceutical, environmental, food safety, and academic labs. What Is a C18 Column? A C18 column consists of a silica-based stationary phase chemically modified with long C18 hydrocarbon chains. These chains provide a strong hydrophobic surface, making the column ideal for retaining and separating non-polar to moderately polar compounds. C18 columns typically come in various particle sizes (e.g., 3 µm, 5 µm) and lengths (e.g., 150 mm, 250 mm), allowing for versatility in resolution, speed, and pressure. C18 Column Structu...