Mass spectrometry imaging source achieves a spatial resolution of 2–3 μm

Hefei Neo Source Instrument Technology Co., Ltd. (Neo Source INSTRUMENT) has launched the MSI LDPI laser/photochemical ionisation mass spectrometry imaging source, which achieves a spatial resolution of 2–3 μm, placing it among the industry leaders. This imaging source is compatible with mainstream mass spectrometers from Agilent, AB SCIEX and Thermo, enabling existing mass spectrometry platforms to acquire mass spectrometry imaging capabilities without the need to replace the entire analytical system.

The core of mass spectrometry imaging lies in acquiring mass spectra corresponding to each pixel on a point-by-point basis whilst preserving the spatial position of the sample, and then reconstructing a visualised molecular distribution map showing ‘where a particular molecule is located and at what concentration’. Resolution determines how fine a structure can be discerned in this map—a resolution of 2–3 μm means that molecular distributions at the single-cell scale can also be distinguished.

New Source had previously launched the MSI DPI electrospray/photochemical ionisation mass spectrometry imaging source, with a resolution of 20–200 μm, suitable for imaging large-scale samples such as tissues and materials. LDPI further advances spatial resolution to the micrometre level, forming a complementary ‘broad-to-fine’ combination with DPI, covering different research scales ranging from tissue regions to single cells.

In terms of the technical approach, New Source’s imaging sources are centred on photoionisation: vacuum ultraviolet (VUV) photons are used to ionise sample molecules, which are then introduced into the mass spectrometer. LDPI integrates laser desorption and photochemical ionisation within a single system, offering broad applicability to neutral molecules at atmospheric pressure, such as lipids, metabolites and drug molecules. Post-photoionisation (also known as secondary photoionisation) technology uses VUV photons to perform secondary ionisation on already vaporised neutral molecules, thereby enhancing signal gain by 1–3 orders of magnitude, which is particularly advantageous for the study of weak signals and low-abundance components.

New Source and the host institution, Professor Pan Yang’s research group at the University of Science and Technology of China, have a long-standing collaborative history in the field of photoionisation mass spectrometry. Professor Pan Yang’s group has published a series of studies on vacuum ultraviolet photoionisation and the development of mass spectrometry instruments; the company’s imaging source products have transformed some of these methods into instrument modules capable of stable operation.

From an application perspective, mass spectrometry imaging is expanding from research settings towards more specific industrial needs: molecular subtyping of tumour tissues, verification of the uniformity of active ingredient distribution in tablets, and the spatial localisation of target compounds in food and traditional Chinese medicinal materials are all areas that have been the subject of considerable recent discussion. As an ‘upstream component’ of mass spectrometers, the significance of imaging sources lies in enabling users who have already purchased mass spectrometers to acquire imaging capabilities at a relatively low retrofitting cost.

Industry observers believe that the barriers to entry for mass spectrometry imaging have long centred on three areas: ‘ionisation sources, imaging control software and interfaces with mass spectrometry platforms’. If an imaging source can be reliably compatible with mainstream mass spectrometry platforms and deliver reproducible spatial resolution, it will lower the barrier for research and quality control organisations to adopt this technology. New Ceyuan has now advanced the resolution of the LDPI to 2–3 μm and specified compatibility with Agilent, AB SCIEX and Thermo, marking a milestone in its ongoing investment in this field.

At the time of writing, both MSI LDPI and MSI DPI are available as standalone imaging source products; please refer to New Ceyuan’s official documentation for specific parameters and compatible models.