Infrared pulsed fiber laser‐produced silver‐109 nanoparticles for laser desorption/ionization mass spectrometry of 3‐hydroxycarboxylic acids

Abstract

Rationale3‐Hydroxycarboxylic acids are one of the major components of bacterial lipopolysaccharides (LPS), also known as endotoxins. Endotoxins pose a serious health risk and can seriously damage the internal organs of humans and animals. 3‐Hydroxycarboxylic acids can be used as environmental markers to determine endotoxin levels. At the time of preparation of this manuscript no studies on laser mass spectrometry (MS) and analysis with silver nanoparticles (NP) for 3‐hydroxycarboxylic acids have been published in literature.MethodsSix acids, 3‐hydroxyoctanoic (3‐OH‐C8:0), 3‐hydroxydecanoic (3‐OH‐C10:0), 3‐hydroxydodecanoic (3‐OH‐C12:0), 3‐hydroxytetradecanoic (3‐OH‐C14:0), 3‐hydroxyhexadecanoic (3‐OH‐C16:0), and 3‐hydroxyoctadecanoic (3‐OH‐C18:0) acids, were used as test compounds on the target containing silver‐109 NPs for quantification using matrix‐assisted laser desorption/ionization (MALDI)–type mass spectrometer. Methods were also tested on spiked human blood serum samples to quantify 3‐hydroxycarboxylic acids and verify the influence of the biological matrix on the measurement.ResultsAnalyzed acids were directly tested in 1 000 000‐fold concentration change conditions ranging from 1 mg/mL to 1 ng/mL. The semi‐automatic MSI (MS imaging) method allowed us to obtain two to five times lower limit of detection (LOD) and lower limit of quantitation (LLOQ) values than common LDI (Bruker Daltonics, Bremen, Germany) method for analyzed acids. For almost all results of 3‐hydroxycarboxylic acids, the trendline fit was better for the semi‐automatic MSI method than the manual LDI method.ConclusionFor the first time, the use of laser MS for the quantification of 3‐hydroxycarboxylic acids has been demonstrated, and it has been proven that it can be used in the quantitative analysis of such compounds over a wide range of concentrations. In addition, a comparison of two methods—manual LDI‐MS and semi‐automatic MSI—is presented.

Fiber Laser-Generated Silver-109 Nanoparticles for Laser Desorption/Ionization Mass Spectrometry of Illicit Drugs

“…In this research, the applicability of 109 AgNPs-assisted laser desorption/ionization MS for identification and quantification of fentanyl and other drugs, such as THC and its two metabolites, as well as opioids, including tramadol, 6-monoacetylmorphine (6-MAM), codeine, methadone, and heroin, was presented. Silver-109 nanoparticle-enhanced LDI applicability for samples of various compositions has been presented by our team in the past. ,, Obtained mass spectra are presented in Figures –. The list of identified ions with the average signal intensity and signal-to-noise ratio of the analyzed compounds at a concentration of 100 μg/mL is presented in Table .…”

“…Silver-109 nanoparticle-enhanced LDI applicability for samples of various compositions has been presented by our team in the past. 19,21,25 Obtained mass spectra are presented in Figures 1−3. The list of identified ions with the average signal intensity and signal-to-noise ratio of the analyzed compounds at a concentration of 100 μg/mL is presented in Table 1.…”

“…In this study, the applied analytical method allowed for rapid screening for fentanyl and other illicit drugs. The sample preparation for 109 AgNP-assisted LDI MS is a matter of minutes, with the spectral data acquisition itself taking even less time. − Recently, our research has successfully applied this technique for both qualitative and quantitative analysis of low molecular weight compounds, including amino acids, − carboxylic acids, − and hormones . Furthermore, this method has shown exceptional utility in analyzing microorganisms − and various human biological samples such as serum, urine, , and tissue.…”