Recent advances in sample preparation techniques for quantitative detection of pharmaceuticals in biological samples

Due to the growing requirement of drug development and the increasing concern of pharmaceutical presence in the environment, bioanalysis of pharmaceuticals has raised much attention to researchers in recent years. However, the complex sample matrices and extremely low content of pharmaceuticals in biological samples are the major constraints. Therefore, great efforts have been made to overcome the subsistent difficulties in recent years, which depend mostly on sample preparation techniques. As a growing trend, developing sample preparation methodologies highlighting high throughput, automatic, on-site, non-invasive and in vivo analysis is highly recommended, which contributes greatly to both biomedical and environmental analysis. Herein, recent advances in sample preparation techniques for quantitative bioanalysis of pharmaceuticals in the past decade are reviewed and summarized, and the relative merits of each sample preparation technique are discussed. Besides, novel techniques such as electromembrane extraction and microfluidic devices are also addressed. Finally, sample preparation techniques which possess the potential for in vivo pharmaceutical analysis will be highlighted as the future trend, and prospects including miniaturization, high specificity and portability will also be discussed.