Category: Advances in Bioanalytics and Biomarkers

1182-C - Sample-per-second shotgun lipidomics using acoustically-induced electrospray ionisation

Tuesday, February 6, 2018
2:00 PM - 3:00 PM

Lipids are abundant components of cell membranes that have vital roles beyond structural support. The identity and abundance of lipid species vary significantly between cell types and cellular states, as such, lipid profiles can provide significant insight as a cell based readout within drug discovery. Current technologies for lipid profiling (HPLC MS/MS and direct infusion ESI-MS/MS) have relatively low sample throughput. Astrazeneca, together with Labcyte and Waters, have developed a workflow which allows rapid analysis of cellular lipid composition from small cell populations grown in a 384-well plate.

We use the recently developed EchoMS platform (Sinclair et al., JALA, 2016), which combines Labcyte Echo liquid dispenser and Waters qToF mass spectrometer. The externalised acoustic transducer together with a charging cone suspended above a well generate a spray of charged droplets (1-20 µm diameter) that desolvate on transit to the MS source through a heated ion transfer optic. A robust XY-stage and the contactless nature of introducing samples into the mass spectrometer prevents any carryover and allows ultrafast (subsecond) sample analysis.

 We demonstrate the ability of EchoMS to analyse lipids directly from adherent or suspension mammalian cells grown in 384-well microtitre plates. Less than 1000 cells are needed to identify and quantify the relative abundance of glycerophosphocholines, sphingomyelins and other lipid species. Minimal sample preparation is required and lipid samples can be analysed using both positive and negative ion modes. In situ lipid extraction can be performed (in well) to improve ionisation of phospholipids and minimise ion suppression.

Jonathan Wingfield

Principle Scientist
Cambridge, England, United Kingdom

Joined AZ in 2000, as part of a team responsible for delivering automation solutions and technology in to the disease area teams post HTS. Was invited to establish a Lead Generation Automation team within Oncology and this evolved into a centralised biochemical screening team in 2006. The centralised team utilized leading-edge technology to deliver high-quality data to global projects, this included delivery of acoustic droplet ejection technology. When the Discovery Sciences function was established within AZ, I moved into a science role supporting biochemical SAR. I remain interested in landing technologies that can add value to our core business, one such example is the acoustic mass spectrometry collaboration between Labcyte and AZ. This project won the SLAS Innovation award (2015) and has generated a significant amount of external interest.