A Portable Mass Spectrometer that Writes History
- Published: Wednesday, 10 June 2020 13:20
Computer downsizing from mainframes, mini, micro, until now the hand held devices, it happened one after another one so fast yet made major impact to human history. Now, the same kind of evolution may happen again to Mass Spectrometers.
Mass Spectrometers are considered high-end equipment that can provide component in-formation for miniscule substances in scales from atom to molecule. Like computers at its mainframe times, they require big budgets to purchase and maintain. They are “a must” for scientific studies nowadays, and there are varieties needed due to different specifica-tions. There are several large mass devices in the Mass Spec core facility in Genomics Research Center.
Dr. Winston Chen has aimed to develop a one-for-all portable mass spectrometer ever since he joined GRC. He believed the downsizing is achievable, and his goal was to build a device that every lab can acquire without financial hassles. For years, Dr. Chen teamed up with Dr. Jung-Lee Lin to materialize their mutual vision.
A commercially available biological mass spectrometer is already in the market after tech transferred to a Taiwanese company Acromass Inc.. The first generation downsized Mass Spectrometer has one tenth in size compared to counterparts, and is able to detect mol-ecules in cell sizes.
The team has plans more than that. Funded by the Taiwan Advanced Instrumentation Project from Academia Sinica, they recently released a newer design that can integrate four ionization sources into one machine, so a much broader subjects can be measured. The design include MALDI (matrix-assisted laser desorption/ionization), ESI (elec-trospray ionization), LIAD (laser induced acoustic desorption/ionization and EI (electron ionization). A detailed report was published in the journal Analyst as well. The photo of the work was chosen as cover page.
A Mass spectrometer usually has three major parts: the ion source, the analyzer, and the detector. Most of the currently available conventional machines require a vacuum chamber to do the analysis, and that is why the machines are huge in size. To conquer that problem, the team used “ion trap” so that with a mini pump to suck out most of the air can provide good enough vacuum space for the analysis. This is the key to their downsizing strategy.
As opposed to the “voltage scan” method used by common machines, the team came up with a “radio scan” method, by varying RF frequency they can obtain the ion spectrum to measure subjects from atoms to cells. The mass spectrum range is from single digit to 1015.
Another problem to the current situation is, each kind of available MS device is always designed for a certain ion source. In order to be versatile, a lab needs to acquire several machines. This automatically sets a high threshold and limits many scientific creativities.
“To measure liquid samples, electrospray ionization (ESI) is used, while measuring solid samples requires matrix-assisted laser desorption / ionization (MALDI) method.” ex-plained Dr. Lin. ”By adding the two methods into one machine, we can extend our targets to a much larger scale. For example, a glycol-protein can weigh in million daltons, and their design can be used to analyze proteins and peptides as well as atoms or small mol-ecules.”
|Portable MS(top), Linear ion trap(left)and MALDI-TOF(right)|
An immediate application was proved achievable already. To echo the request to outreach scientific inventions to the society, they have managed to use their invention in drug abuse prevention tasks. Law enforcers can actually take the machine with them while doing their busting checks and get evidences at the spot.
The developers are excited because their newest development can be the beginning of pushing mass spectrometer for community or personal use in the future. It can help in assuring food safety, illegal drug detection, bacteria/virus detection, environmental as-sessment and health evaluation.
A mass spectrometer revolution is surely on its way!
The original article can be read online at Analyst website: https://pubs.rsc.org/en/content/articlelanding/2020/an/d0an00126k#!divAbstract