The Role of Carbon Nanomaterials in Sample Preparation: Review

Sample preparation plays a vital role in analytical chemistry, particularly for the isolation and enrichment of trace analytes from complex matrices. Conventional techniques such as solid-phase extraction (SPE) and solid-phase microextraction (SPME) are widely employed; however, their efficiency is often limited by the performance of traditional sorbents. These conventional materials may suffer from low selectivity, limited adsorption capacity, and reduced stability under varying analytical conditions. As a result, there has been growing interest in developing advanced materials that can overcome these limitations and enhance analytical performance. Recent advances in nanotechnology have introduced carbon-based nanomaterials as promising alternatives for improving extraction efficiency and selectivity. Materials such as graphene, graphene oxide, and carbon nanotubes (CNTs) exhibit unique physicochemical properties, including exceptionally large surface area, tunable surface functionality, high mechanical strength, and strong π–π interactions with a wide range of analytes. These features enable more efficient adsorption and improved sensitivity in analytical procedures. This review summarizes recent developments in the application of graphene and CNT-based nanomaterials for SPE, magnetic SPE (MSPE), and SPME. Their synthesis methods, surface modification strategies, and characterization techniques are discussed in detail. Furthermore, their analytical performance in environmental, food, and biological sample analysis is critically evaluated. The advantages, current limitations, and future prospects of carbon nanomaterials in enhancing analytical sample preparation are also highlighted, emphasizing their potential role in advancing modern analytical methodologies.