Open Port Probe Sampling Interface for the Direct Coupling of Biocompatible Solid-Phase Microextraction to Atmospheric Pressure Ionization Mass Spectrometry

Abstract

In recent years, the direct coupling of solid phase microextraction (SPME) and mass spectrometry (MS) has shown its great potential to improve limits of quantitation, accelerate analysis throughput, and diminish potential matrix effects when compared to direct injection to MS. In this study, we introduce the open port probe (OPP) as a robust interface to couple biocompatible SPME (Bio-SPME) fibers to MS systems for direct electrospray ionization. The presented design consisted of minimal alterations to the front-end of the instrument and provided better sensitivity, simplicity, speed, wider compound coverage, and high-throughput in comparison to the LC-MS based approach. Quantitative determination of clenbuterol, fentanyl, and buprenorphine was successfully achieved in human urine. Despite the use of short extraction/desorption times (5 min/5 s), limits of quantitation below the minimum required performance levels (MRPL) set by the world antidoping agency (WADA) were obtained with good accuracy (≥90%) and linearity (R > 0.99) over the range evaluated for all analytes using sample volumes of 300 μL. In-line technologies such as multiple reaction monitoring with multistage fragmentation (MRM) and differential mobility spectrometry (DMS) were used to enhance the selectivity of the method without compromising analysis speed. On the basis of calculations, once coupled to high throughput, this method can potentially yield preparation times as low as 15 s per sample based on the 96-well plate format. Our results demonstrated that Bio-SPME-OPP-MS efficiently integrates sampling/sample cleanup and atmospheric pressure ionization, making it an advantageous configuration for several bioanalytical applications, including doping in sports, in vivo tissue sampling, and therapeutic drug monitoring.

Analysis of human gliomas by swab touch spray-mass spectrometry: applications to intraoperative assessment of surgical margins and presence of oncometabolites

“…Electrospray ionization occurs readily from the porous material of the swab tip, similarly to paper spray 15, 16 and biocompatible solid phase micro-extraction fibers. 17, 18 …”

Fast screening of illicit drugs in beverages and biological fluids by direct coupling of thin film microextraction to dielectric barrier discharge ionization-mass spectrometry

“…Gómez-Ríos et al reported the analysis of drugs of abuse in human urine and plasma at the sub-ppb concentration level by using an open port probe (OPP) ionization source. 30 Tascon et al quantified immunosuppressants in whole blood at the sub-ppb level with a microfluidic open interface (MOI) ionization source. 31 Coated blade spray 32 (CBS) was also used for the quantification od drugs of abuse in human urine and plasma.…”

Microextraction sample preparation techniques in forensic analytical toxicology

“…As happens with the classic SPE cartridges, the SPME LC fiber is designed for single use; however, it can be reused by implementing a cleaning step after the desorption cycle with a mixture of solvents such as methanol, isopropanol and acetonitrile (Gomez‐Rios et al, ). The reusability of the fiber highly depends on factors such as sample matrix, the effectiveness of fiber cleaning and desorption conditions.…”

“…This method can detect prohibited substances in biofluids rapidly via direct analysis. The open port probe sampling interface was designed for direct coupling of biocompatible SPME fibers to MS systems for direct electrospray ionization and quantitative determination of clenbuterol, fentanyl and buprenorphine in human urine (Gomez‐Rios et al, ). These techniques are still in the early development stage with prototypes available.…”