MSACL 2018 US Abstract

Topic: Small Molecules / Tox

Can LC-MS be Replaced by Direct Coupling of SPME to MS in Clinical Applications?

German Gomez-Rios (Presenter)
University of Waterloo

Bio: I am Ph.D. in Analytical Chemistry and currently working on the development of a rapid diagnostic tool for targeted in-vivo, ex-vivo and on-site analysis. This technology is based on the direct coupling of biocompatible Solid Phase Micro Extraction (SPME) devices to mass spectrometry instruments using different ionization techniques such as Direct Analysis in Real Time (DART), Desorption Electro Spray Ionization (DESI), nano-Electro Spray Ionization (nano-ESI), Open Port Probe (OPP), Dielectric Barrier Desorption Ionization (DBDI) and Coated Blade Spray (CBS). My research is mainly focused on the improvement of the technology in order to provide novel, accurate, fast, and low-cost assays of biological fluids and tissue, allowing medical doctors and surgeons to individualize patient’s treatment.

Authorship: German Gomez-Rios, Marcos Tascon, Alexander Kasperkiewicz, Vinicius Aquaro, Daniel Rickert, Nathaly Reyes-Garces, Ezel Boyaci, Sofia Lendor, Varoon Singh, Janusz Pawliszyn
University of Waterloo, Waterloo, Canada

Short Abstract

This work presents most recent developments in Coated Blade Spray (CBS)-Mass Spectrometry towards the analysis of small molecules in biofluids. For instance, we explore novel strategies for analysis of small sample volumes (blood droplets) as well as a new methodology for rapid analysis of controlled substances in urine and plasma samples (under 15s per sample).

Long Abstract

Introduction

Coated Blade Spray (CBS) is a SPME-based technology designed for the enrichment of analytes of interest from complex sample matrices, which can be directly coupled with mass spectrometry instruments for rapid quantitative/qualitative analysis. Unlike other SPME-MS couplings, no-additional instrumentation is required as the blade acts as the extraction device/ionization-source. Moreover, when dealing with small volumes, no container is needed as the sample can be simply spotted onto the coated area. Due to the ultra-thin and biocompatible nature of the coatings, fast extraction/enrichment of the target analytes can be achieved with negligible adherence of matrix components onto the coated surface. Herein, we describe the most recent advances on CBS-technology towards the analysis of small molecules of potential interest in clinical and forensic applications.

Methods

The analytical protocol consists of three steps: 1. analyte-enrichment: either by spotting the sample onto the CBS, or by extracting from a vessel containing the sample; 2. coating-cleaning: fast removal of matrix potentially adhered to the coated surface; and c. instrumental-analysis: applying 10µL of the elution/electrospray solution (e.g. 95/5/0.01 % methanol-water-formic acid) onto the CBS, which is placed 5 mm from the MS inlet. After 20s, a +4kV potential difference was applied resulting in ESI from the tip of the blade. Signal was integrated for 1-30s according to the application. Analysis were performed using either a Q-Exactive or a TSQ-Quantiva (Thermo Scientific, San Jose, USA). CBS were coated with a HLB/C18-PAN slurry using a dip-coating method developed in our laboratory.

Results

This work describes most recent advances on CBS-technology that have shifted the paradigm related to the direct coupling of SPME to MS for clinical applications. First, we present a CBS-autosampler that allows for processing of up to 96-samples simultaneously and the subsequent unsupervised MS-event of each CBS. This technology was assessed for the quantitative determination of drugs in urine, blood and plasma samples. Model analytes with a wide variety of physical-chemical and protein binding properties, including doping agents (e.g. clenbuterol), pain-management drugs (e.g. fentanyl), and therapeutic-drugs (e.g. tacrolimus) were selected for this study. Our results demonstrated that CBS can provide satisfactory linearity over 3 orders of magnitude (pg/mL to ng/mL) and great accuracy (85-120%) for the majority of the probes selected. Second, we introduce a ground-breaking strategy that allows lowering LOQ when determining therapeutic-drugs/controlled-substances in biofluids spots by neglecting the “solventless” philosophy of SPME. This approach is further exploited towards the concomitant analysis of immunosuppressive, antifungal and pain-panel drugs from a blood droplet. Third, we describe diverse on-coating derivatization methodologies developed to enhance limits-of-quantitation for targeted analytes with poor ionization efficiency/high-instrumental background. Finally, we introduce the fastest CBS-MS method developed to date with a total analysis time per sample under 15s. This method, which consists of an extraction time of approximately 9s per sample and 1.8s of MS-analysis time (5 ms dwell time), was tested for the quantitation of 20 substances in plasma and urine samples.

Conclusions & Discussion

The results herein presented demonstrate that CBS is a technology that has great potential to replace existing direct-to-MS technologies and on-line SPE-MS approaches for the quantitative analysis of target compounds in complex matrices such as blood, plasma, and urine. Limits of quantitation in the low nanogram per milliliter range and total analysis times under 1 minute can be attained with this technology.


References & Acknowledgements:

We are grateful to the Natural Sciences and Engineering Research Council (NSERC) of Canada for their financial support through an Industrial Research Chair program. We would also like to thank Thermo Fisher Scientific for lending us the triple quadrupole mass spectrometer that was used in this work (TSQ Quantiva), which was part of the Industrial Research Chair (IRC) program.

References

1.Development of Coated Blade Spray Ionization Mass Spectrometry for the Quantitation of Target Analytes Present in Complex Matrices. Angewandte Chemie, 2014, 53, 14503-14507.

2.Fast Quantitation of Target Analytes in Small Volumes of Complex Samples by Matrix‐Compatible Solid‐Phase Microextraction Devices. Angewandte Chemie, 2016, 26, 7636-7640.

3. Ultrafast quantitation of voriconazole in human plasma by coated blade spray mass spectrometry, 2017, Journal of Pharmaceutical and Biomedical Analysis, 2017,144, 106-111.

4. High-throughput screening and quantitation of prohibited substances in plasma and urine samples by coated blade spray ionization-mass spectrometry (CBS-MS), 2017, Analytical Chemistry, 2017, 89, 8421–8428.

5. Rapid and concomitant analysis of pharmaceuticals in treated waste water by coated blade spray-mass spectrometry water by coated blade spray (CBS), 2017, Environmental Science & Technology. (manuscript in press) DOI: 10.1021/acs.est.7b03867


Financial Disclosure

DescriptionY/NSource
Grantsno
Salaryno
Board Memberno
Stockno
Expensesno

IP Royalty: no

Planning to mention or discuss specific products or technology of the company(ies) listed above:

no