Octadecylsilane chemically bonded silica is widely used in chromatography as a stationary phase. Its hydrophobic nature makes it ideal for reverse-phase chromatography, where it effectively separates non-polar compounds. This material is commonly applied in the analysis of pharmaceuticals, environmental samples, and biological fluids, providing high resolution and reproducibility. Additionally, it is utilized in solid-phase extraction to isolate and concentrate target analytes from complex matrices, enhancing the sensitivity and accuracy of analytical methods. Its stability and durability under various pH conditions further contribute to its widespread use in analytical chemistry.