Dataset Information

Proteomic analysis of single tears from healthy human subjects

ABSTRACT: 23 volunteers were recruited for this study. Tears were collected using microcapillary tubes (MCT). For each volunteer, a single tear sample was taken from one eye. For two of these volunteers, the procedure was performed in the morning (9-10 AM) and in the afternoon (5-6 PM) on the same day, once a week for 3 consecutive weeks. Proteins were purified from 5 uL of tear sample using the methanol-chloroform precipitation protocol. The lyophilized proteins were resuspended in ammonium bicarbonate 50 mM, pH 8. An in-solution trypsin digestion was performed. For each run, 1 ug of peptides was injected and each sample was injected twice. Analyses were performed by LC-MS/MS using an Orbitrap Fusion mass spectrometer coupled to an EASY-nLC 1000 nanoflow high-pressure liquid chromatography. Peptides were separated on a commercial analytical nanocolumn. MS scans were performed using the Orbitrap (OT) analyzer with a resolution of 120 000. Precursor ions were selected for higher collisional dissociation (HCD) and the collision energy was set to 30%. Dynamic exclusion was set at 45 s, with a repeat count of 1.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Homo Sapiens (ncbitaxon:9606)

SUBMITTER: Erika Ponzini

PROVIDER: MSV000087703 | MassIVE | Fri Jun 25 08:03:00 BST 2021

REPOSITORIES: MassIVE

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Publications

Single-Tear Proteomics: A Feasible Approach to Precision Medicine.

Ponzini Erika E Ami Diletta D Duse Alessandro A Santambrogio Carlo C De Palma Antonella A Di Silvestre Dario D Mauri Pierluigi P Pezzoli Fabio F Natalello Antonino A Tavazzi Silvia S Grandori Rita R

International journal of molecular sciences 20211004 19

Lacrimal fluid is an attractive source of noninvasive biomarkers, the main limitation being the small sample amounts typically collected. Advanced analytical methods to allow for proteomics profiling from a few microliters are needed to develop innovative biomarkers, with attractive perspectives of applications to precision medicine. This work describes an effective, analytical pipeline for single-tear analysis by ultrahigh-resolution, shotgun proteomics from 23 healthy human volunteers, leading ...[more]

PMID: 34639092

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