Development of a SBSE-HPLC method using sol-gel based germania coated twister for the analysis of 4-chloro-1-naphthol in biological and water samples

Solventless Microextration Techniques for Pharmaceutical Analysis: The Greener Solution

Extensive efforts have been made in the last decades to simplify the holistic sample preparation process. The idea of maximizing the extraction efficiency along with the reduction of extraction time, minimization/elimination of hazardous solvents, and miniaturization of the extraction device, eliminating sample pre- and posttreatment steps and reducing the sample volume requirement is always the goal for an analyst as it ensures the method’s congruency with the green analytical chemistry (GAC) principles and steps toward sustainability. In this context, the microextraction techniques such as solid-phase microextraction (SPME), stir bar sorptive extraction (SBSE), microextraction by packed sorbent (MEPS), fabric phase sorptive extraction (FPSE), in-tube extraction dynamic headspace (ITEX-DHS), and PAL SPME Arrow are being very active areas of research. To help transition into wider applications, the new solventless microextraction techniques have to be commercialized, automated, and validated, and their operating principles to be anchored to theory. In this work, the benefits and drawbacks of the advanced microextraction techniques will be discussed and compared, together with their applicability to the analysis of pharmaceuticals in different matrices.

Stir bar sorptive extraction and its application

Recent progress of stir bar sorptive extraction (SBSE) in the past six years is reviewed. The preparation methods including electrodeposition, self-assembly, solvent exchange, physical magnetic adsorption and electrostatic spinning, for the coated stir bar are summarized and compared, specifically for a specific material for coatings fabrication, e.g., carbon-based materials and metal organic frameworks. The emerging materials (e.g., graphene, graphene oxide, carbon nanotubes, monolith, metal-organic frameworks and porous organic polymers) applied for coated stir bar fabrication are one of the focus of this review, along with their respective advantages in extraction process and application in trace analysis. The development and application of extraction apparatus of SBSE are also involved. Based on these information, the development status and prospects of SBSE as an efficient sample pretreatment technique in real sample analysis are discussed.

A banana peel/silicon glue coated stir bar for extraction of aspirin, diclofenac, ibuprofen and mefenamic acid followed by high performance liquid chromatography-UV detection

In the current study, a green, cost-effective, and bio-degradable additive was used for the preparation of a highly efficient sorbent based on silicon glue. Here, a banana peel was pretreated and mixed with silicon glue. It was proved that the prepared banana peel-silicon glue bar is a reliable sorbent for stir bar sorptive extraction of nonsteroidal anti-inflammatory drugs (NSAIDs) including aspirin, diclofenac, ibuprofen and mefenamic acid in human urine and plasma. Compared to the lab-made sorbents, the prepared sorbent showed high extraction performance, high stability, and satisfactory reproducibility and involved easy preparation. In order to optimize the effective factors, different parameters such as (stirring rate, pH, extraction time, desorption time and elution solvent volume) were optimized using response surface methodology (RSM) through applying Central-Composite Design (CCD). Under the optimum conditions, the linear dynamic ranges of the target analytes were investigated in the range of 0.2-200 μg L^-1 with r² higher than 0.9929. Limits of detection (LODs) and limits of quantification (LOQs) of analytes were in the ranges of 0.04-0.5 and 0.15-1.65, respectively. The reproducibility of the method was also investigated by calculating the relative standard deviation. The RSD was measured to be lower than 4.9%. Bar-to-bar reproducibility at a 100 μg L^-1 concentration level was also evaluated to be lower than 5.3% (n = 3). Also, each prepared film can be used up to 64 times without any reduction in extraction performance. Finally, the method was successfully applied for the determination of selected drugs in different biological fluids including urine and plasma samples. The calculated relative recovery in real sample analysis was higher than 90%.