Nasal exudate for diagnosis of stroke: fundamental studies through iron fractionation, total iron, and targeted protein determinations

• Published in: Analytical and bioanalytical chemistry Vol. 416; no. 24; pp. 5365 - 5375
• Main Authors: Marina-Latorre, Marta, Lobo, Lara, García-Cabo, Carmen, Benavente-Fernández, Lorena, Calleja-Puerta, Sergio, Fernández-Abedul, M. Teresa, González-Iglesias, Héctor, Pereiro, Rosario
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2024; Springer Nature B.V
• Subjects: Aged; Analytical Chemistry; Biochemistry; Biological analysis; Brain research; Cation Transport Proteins; Characterization and Evaluation of Materials; Chemical Fractionation - methods; Chemistry; Chemistry and Materials Science; Chromatography; Column chromatography; Diagnosis; Dilution; Enzyme-Linked Immunosorbent Assay - methods; Exudates and Transudates - chemistry; Exudation; Female; Ferritin; Ferritins - analysis; Food Science; Fractionation; gel chromatography; Hemorrhage; Human subjects; Humans; Inductively coupled plasma; Iron; Iron - analysis; Ischemia; isotope dilution technique; Laboratory Medicine; Lactoferrin; Lactoferrin - analysis; Male; Mass spectrometry; Mass Spectrometry - methods; Mass spectroscopy; Metabolism; Middle Aged; Monitoring/Environmental Analysis; nose; Proteins; Radiochemical analysis; Research Paper; Sampling; Scientific imaging; Signal transduction; Size exclusion chromatography; spectroscopy; Stroke; Stroke - diagnosis; Tomography; Transferrin; Transferrin - analysis; Nasal exudate; Size exclusion chromatography; Isotope dilution analysis; Stroke; Elemental analysis; HPLC-ICP-MS
• DOI: 10.1007/s00216-024-05469-5
• ISSN: 1618-2642; 1618-2650

During the last years, there has been an increasing research interest in the analysis of biological fluids requiring non-invasive sampling for biomedical and clinical applications. In this work, we have focused on the nasal exudate with the aim of investigating the potential use of this fluid to know the role of iron in stroke and also for diagnosis. Potential differences in the nasal exudate, collected in swabs, from diagnosed hemorrhagic stroke, ischemic stroke, and control groups were investigated with regard to total iron by inductively coupled plasma-mass spectrometry, iron fractionation studies by size exclusion chromatography together with post-column isotope dilution analysis, and four proteins containing iron (ferritin, transferrin, lactoferrin, and ferroportin) with ELISA kits. All these analyses represent an analytical challenge, considering the rather limited amount of sample (10–40 mg) available, being the nasal exudate extracted from the swab with 300 µL 10 mM Tris/HCl, pH = 7.4. Studies to obtain reliable analytical information, such as the blank contribution of the sampling step, evaluation of the extraction efficiency of the nasal exudate from the swab, and normalization strategies for data treatment, have been carried out. Results showed that despite the limited number of investigated samples, fractionation studies as well as the concentrations of ferritin and ferroportin obtained with ELISA kits showed a differential behavior between the different cohorts.