Paper spray ionization

Paper spray ionization is a technique used in mass spectrometry to produce ions from a sample to be analyzed. It is a variant of electrospray ionization. ^[1] The sample (for instance a few microlitres of blood or urine) is applied to a piece of paper and solvent is added. Then a high voltage is applied, which creates the ions to be analyzed with a mass spectrometer. The method, first described in 2010, ^[2] is relatively easy to use and can detect and measure the presence of various substances in the sample. This technique shows great potential for point-of-care clinical applications, in that important tests may be run and results obtained within a reasonable amount of time in proximity to the patient in a single visit. ^[3] In 2017 it was reported that a test based on paper spray ionization mass spectrometry can detect cocaine use from a subject's fingerprint. ^[4] It was also used to detect pesticides from the surfaces of fruits. ^[5]

More recently, an advanced form of Paper Spray, termed Paper Arrow, was developed. This universal approach seamlessly hyphenates Paper Chromatography and Mass Spectrometry, facilitated by on-paper ionization without requiring visual indicators. The entire process of Paper Arrow was shown to be simple and fast, requiring only 2 μL of raw biological sample. Its analytical performance is in accordance with stringent clinical guidelines, and it demonstrated superior figures of merit compared to LC-MS. ^[6] Paper Arrow is one of the few ambient ionization sources that has been clinically validated. In a study with 17 volunteers, blood and saliva samples were collected before and at 15, 30, 60 and 240 min after ingesting 1 g of paracetamol. Detection from stimulated saliva and plasma with PA-MS provided a reliable result that can aid in making timely treatment decisions. Moreover, participants’ views of blood and saliva sampling procedures were assessed qualitatively, showing a preference for non-invasive sampling. ^[7]

References

1. Meher, Anil Kumar; Chen, Yu-Chie (2017). "Electrospray Modifications for Advancing Mass Spectrometric Analysis". Mass Spectrometry. 6 (Spec Iss): S0057. doi:10.5702/massspectrometry.S0057. PMC   5448333 . PMID   28573082.
2. Liu, Jiangjiang; Wang, He; Manicke, Nicholas E.; Lin, Jin-Ming; Cooks, R. Graham; Ouyang, Zheng (2010-03-15). "Development, characterization, and application of paper spray ionization". Analytical Chemistry. 82 (6): 2463–2471. doi:10.1021/ac902854g. PMID   20158226.
3. Damon, Deidre E.; Davis, Kathryn M.; Moreira, Camila R.; Capone, Patricia; Cruttenden, Riley; Badu-Tawiah, Abraham K. (2016-02-02). "Direct Biofluid Analysis Using Hydrophobic Paper Spray Mass Spectrometry" . Analytical Chemistry. 88 (3): 1878–1884. doi:10.1021/acs.analchem.5b04278. ISSN   0003-2700. PMID   26730614.
4. Glatter, Robert (September 23, 2017). "New Fingerprint Test Can Detect Cocaine Use In Seconds". Forbes.
5. Soparwalla, Santosh; Tadjimukhamedov, Fatkhulla K.; Wiley, Joshua S.; Ouyang, Zheng; Cooks, R. Graham (2011). "In situ analysis of agrochemical residues on fruit using ambient ionization on a handheld mass spectrometer". Analyst. 136 (21): 4392–4396. doi:10.1039/C1AN15493A. PMID   21892448.
6. Zhou, Yufeng; Sham, Tung-Ting; Boisdon, Cedric; Smith, Barry; Blair, Joanne; Hawcutt, Daniel; Maher, Simon (2024). "Emergency diagnosis made easy: matrix removal and analyte enrichment from raw saliva using paper-arrow mass spectrometry". Analyst. 148 (21): 5366–5379. doi: 10.1039/D3AN00850A .
7. Zhou, Yufeng; Dliso, Silothabo; Craske, Jennie; Bracken, Louise; Landa, Kiran; Arnold, Philip; Walker, Laura; Grasin, Ionela; Seddon, Gabrielle; Chen, Tao; Davison, Andrew; Sham, Tung-Ting; Smith, Barry; Hawcutt, Daniel; Maher, Simon (2024). "Rapid and non-invasive analysis of paracetamol overdose using paper arrow-mass spectrometry: a prospective observational study". BMC Medicine. 22 (1): 553. doi: 10.1186/s12916-024-03776-3 . PMC   11590362 .