Fiber-in-tube SPME-CapLC-MS/MS method to determine A β peptides in cerebrospinal fluid obtained from Alzheimer ' s patients

Author(s)

de Souza, Israel Donizeti ; Lancas, Fernando M. ; Hallak, Jaime E. Cecilio ; Queiroz, Maria E. Costa

• Document type: Journal article
• Source: Journal of Chromatography A; v. 1723, p. 7-pg., 2024-04-19.

Abstract

Mass spectrometry is characterized by its high sensitivity, ability to measure very low analyte concentrations, specificity to distinguish between closely related compounds, availability to generate high-throughput methods for screening, and high multiplexing capacity. This technique has been used as a platform to analyze fluid biomarkers for Alzheimer 's disease. However, more effective sample preparation procedures, preferably antibody-independent, and more automated mass spectrometry platforms with improved sensitivity, chromatographic separation, and high throughput are needed for this purpose. This short communication discusses the development of a fiber-in-tube SPME-CapLC-MS/MS method to determine A beta peptides in cerebrospinal fluid obtained from Alzheimer 's disease patients. To obtain the fiber-in-tube SPME capillary, we longitudinally packed 22 nitinol fibers coated with a zwitterionic polymeric ionic liquid into the same length of the PEEK tube. In addition, this communication compares this fiber-in-tube SPME method with the conventional HPLC scale (HPLCMS/MS) and when directly coupled to CapESI-MS/MS without chromatographic separation, and, as a case study, discusses the benefits and challenges inherent in miniaturizing the flow scale of the sample preparation technique ( fiber-in-tube SPME) to the CapLC-MS/MS system. Fiber-in-tube SPME-CapLC-MS/MS provided LLOQ ranging from 0.09 to 0.10 ng mL -1 , accuracy ranging from 91 to 117 % (recovery), and reproducibility of less than 18 % (RSD). Analysis of the cerebrospinal fluid samples obtained from Alzheimer 's disease patients evidenced that the method is robust. At the capillary scale (10 mu L min -1 ), this innovative method presented higher analytical sensitivity than the conventional HPLC-MS/MS scale. Although fiber-in-tube SPME directly coupled to CapESI-MS/MS offers advantages in terms of high throughput, the sample was dispersed and non-quantitatively desorbed from the capillary at low flow rate. These results highlighted that chromatographic separation is important to decrease the matrix effect and to achieve higher detectability, which is indispensable for bioanalysis. (AU)

• FAPESP's process: 20/00126-8 - Development of the methods of the microextraction hyphenated with LC-MS/MS or directly to MS/MS for the determination of biomarkers in biological samples of patient or rats with neurodegenerative diseases
• Grantee: Maria Eugênia Queiroz Nassur
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/21984-0 - Multi-user equipment approved in grant 17/02147-0: electron ionization nano liquid chromatography-mass spectrometry system with a quadrupole analyzer (EI-Q (MS)) - nano-LC-EI-MS
• Grantee: Fernando Mauro Lanças
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 17/21985-6 - Multi-user equipment approved in grant 17/02147-0: electrospray ionization nano/micro liquid chromatography-tandem mass spectrometry system (ESI-QqQ (MS/MS)) - nano/µ-LC-ESI-MS/MS
• Grantee: Fernando Mauro Lanças
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 19/19485-0 - Development of nitinol fiber chemically coated with zwitterionic polymeric ionic liquids for determination of beta-amyloids in plasma samples from patients with Alzheimer's disease by direct coupling fiber-in-tube SPME and MS/MS
• Grantee: Israel Donizeti de Souza
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/02147-0 - Single drop chromatography and its coupling to mass spectrometry: instrumental strategies, development of materials, automation and analytical applications
• Grantee: Fernando Mauro Lanças
• Support Opportunities: Research Projects - Thematic Grants