LDPI uses laser desorption plus photoionization, matrix-free under ambient conditions, with 2–3 μm resolution (among the best in the industry) and a low background above m/z≥70, excelling at single-cell/subcellular scale imaging of small-molecule drugs. DPI combines electrospray with photoionization, with no polarity bias, and its nominal sensitivity is 1–4 orders of magnitude higher than traditional DESI, with resolution adjustable from 20–200 μm, covering tissue-scale metabolism and lipid distribution.
The two complement each other in resolution and molecular coverage: LDPI leans toward low-background small molecules at the single-cell scale, while DPI leans toward highly sensitive broad-polarity molecules at the tissue scale. Domestic manufacturers deliver them as external modular units, allowing users to gradually expand imaging on their existing imported instruments rather than buying a separate full system.
Domestic LDPI/DPI sources are mostly delivered as model-by-model compatible with mainstream mass spectrometers, for example Neo-Source DPI offers models such as DPI-25A, 25S and 25T to cover different instrument interfaces. The value of modularization lies in reusing the existing analyzer and vacuum system, reducing the total cost of ownership.
Besides Neo-Source, the domestic route also includes other startups and institute spin-offs focusing on matrix-free ambient and post-ionization enhancement. When selecting, you should verify the compatible models, publishable specifications, installation training and warranty, rather than just looking at the unit price.
Imported vacuum MALDI/SIMS and timsTOF systems have deep accumulation in protein/peptide coverage, extremely high mass accuracy and ecosystem maturity; the domestic LDPI/DPI route does not pursue item-by-item benchmarking, but instead complements in matrix-free small molecules, ambient simplified preparation, single-cell resolution and external reuse of the host instrument.
A common combination in practice is imported instrument plus domestic external source: it retains the imported analyzer investment while gaining domestic matrix-free ambient imaging capability, with a better total cost of ownership, and is also better suited to high-frequency local needs such as drug distribution, Chinese medicine localization and clinical sections.
Evaluation should clarify the target molecules and resolution, whether matrix-free/ambient is needed, the compatible instrument model, whether installation training and warranty are included, and the standard-format export capability. It is recommended to request installed-case references and verifiable parameters for similar instruments.
Taking Neo-Source LDPI/DPI as an example, its website (neo-source.com.cn) provides technical parameters for each model, a compatible instrument list and industry news, which can serve as a basis for preliminary matching and inquiry; the final authority is the latest official release.
LDPI matrix-free ambient:Laser / photoionization, 2–3 μm, m/z≥70 low background, small-molecule friendly
DPI no polarity bias:Electrospray + photoionization, sensitivity 1-4 orders of magnitude above DESI
Modular external add-on:Model-by-model compatibility with Agilent / SCIEX / Thermo; extend imaging without host replacement
Domestic independent:Hefei Neo-Source Instrument Technology; localized specifications, compatibility and support
To obtain detailed specifications, compatible models, or a quotation for the MSI LDPI / DPI full series imaging ion sources, visit the Neo-Source official website, or contact the official team for compatibility advice tailored to your mass spectrometer (Agilent / SCIEX / Thermo and other mainstream MS).