Solid-Phase Microextraction Research Laboratory
Team SPiRAL
Our laboratory focuses on the development and optimization of Solid Phase Microextraction (SPME) techniques for applications in analytical chemistry and environmental science. We apply SPME to detect pesticide residues in dry fruits, fruits, and vegetables with high sensitivity and accuracy. Our research also includes biomedical applications, such as identifying antibiotic growth promoters and respiratory pathogens. A major goal is to improve SPME performance in complex sample types. We aim to develop reliable and practical methods that support food safety, environmental monitoring, and clinical diagnostics. Through this work, we contribute to advancing analytical tools for public health and safety.
Chlorinated compounds in water pose significant environmental and health concerns, necessitating the development of efficient and rapid monitoring strategies to ensure environmental protection and regulatory compliance. Unlike conventional analytical approaches that often involve complex sample preparation and instrumentation, our group has developed a novel paper-based thin film solid-phase microextraction (TF-SPME) patch for the detection of 4-chlorophenol (4-CRP), a well-established and hazardous environmental pollutant. This innovative platform integrates a composite of divinylbenzene, polydimethylsiloxane, and multi-walled carbon nanotubes onto a paper substrate using a thin film applicator, enabling uniform coating and enhanced extraction capability. In our testing, TF-SPME patches were directly exposed to aqueous solutions containing varying concentrations of 4-CRP and subsequently analyzed using gas chromatography–mass spectrometry (GC-MS). Our data revealed strong extraction performance with a detection limit of approximately 10 ng/mL, highlighting the practical utility of this technique for monitoring chlorinated contaminants within acceptable regulatory limits. To evaluate the quantitative capacity of the method, we generated a calibration curve across a concentration range of 100–10,000 ng/mL, resulting in a precise curve-fitting equation for estimating unknown 4-CRP levels. These findings underscore the potential of our paper-based TF-SPME system as a simple, scalable, and cost-effective solution for the real-time surveillance of hazardous pollutants in water. Ongoing research in our laboratory aims to expand the applicability of this platform to other chlorinated compounds and further optimize its integration into environmental monitoring workflows.
Fabrication of disposable microextraction analytical tool for in vitro detection of Staphylococcus bacterial pathogen using volatile metabolites emission
A disposable paper-based thin film solid-phase microextraction (TF-SPME) patch was developed for the detection of Staphylococcus aureus bacterial pathogen. The study was based on the extraction of volatile organic compounds from the bacterial culture medium by a nanoparticle blended polymer-coated microextraction patch and then analyzed by gas chromatography-mass spectrometry to identify the volatile metabolic signature associated with the bacterial pathogen during the growth phase of the bacterial species in the culture medium. The TF-SPME patches were fabricated using a divinylbenzene/multiwall carbon nanotube/polydimethylsiloxane coating mixture employing a film applicator for uniform coating on a regular cellular paper substrate. The coated sheet was dried and trimmed into multiple small-dimension sampling patches before exposure to the Staphylococcus bacterial solution. To check the eco-friendliness of the proposed technique in terms of green analytical chemistry, the ‘Blue Applicability Grade Index’ (BAGI) was determined to be around 62.5, suggesting the feasibility of considering the proposed analytical method as a green sample preparation approach for clinical application. Therefore, this technique utilizing the TF-SPME patches may be utilized as an alternative and rapid method for the identification of Staphylococcus bacterial pathogens as an alternative to the traditional prolonged culture-based study. Furthermore, the microextraction patch is disposable and easy to fabricate, suggesting the feasibility of utilizing it as a pathological sampling kit for the characterization of Staphylococcus bacterial pathogen.
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Development of a disposable paper-based thin film solid-phase microextraction sampling kit to quantify ketone body
Diabetes ketoacidosis (DKA) is a life-threatening complication that requires immediate medical attention in diabetes subjects, especially with type 1 diabetes mellitus. In DKA, the body produces excess ketone bodies after unregulated fat degradation, causing blood to become acidic and hampering normal metabolic activities. The current diagnostic technique for DKA relies on monitoring ketone bodies, particularly β-hydroxybutyric acid, from urine and blood samples. This study developed a paper-based patch operating on the thin film solid-phase microextraction (TF-SPME) principle, coupled with gas chromatography-mass spectrometry for quantifying β-hydroxybutyric acid (BHB). The patches were fabricated using an A4 paper substrate coated with multiwalled carbon nanotubes (MWCNT), polydimethylsiloxane (PDMS), and divinyl benzene (DVB). Extraction of BHB was performed with DVB/PDMS and DVB/CNT/PDMS patches, followed by desorption with acetonitrile for gas chromatography-mass spectrometry analysis. Our study found that BHB extraction efficiency was higher using DVB/PDMS-coated patches, demonstrating good linearity (R² = 0.99) within the 500–20,000 ng mL⁻¹ concentration range. This work highlights the potential of using simple, cost-effective paper-based disposable TF-SPME patches as a sampling kit for screening diabetes ketoacidosis without extensive traditional sample preparation in pathology.