Imagine, Sniffing Molecules
Imagine a device that could analyze the molecular components of a sample by „sniffing“ them. This method is known as „Direct Screening“ and gained prominence, especially in the mid-2000s, when it became possible in combination with highly sensitive mass spectrometers (= Direct MS). Read in this article, what Direct MS means for research and analysis laboratories, the potential of this new method, and the challenges that still exist after nearly twenty years of development.
Let’s Start from the Beginning: Sniffing Molecules?
For a molecular analysis, the sample is typically prepared in the laboratory and then separated into its individual components using a chromatograph. Subsequently, these components are ionized through an ion source, or „charged,“ allowing them to be „weighed“ in a mass spectrometer (MS), with their respective mass attributed to a specific molecule.
Usually, such an analysis requires a chromatograph for liquid (LC) or gaseous substances (GC), an ion source, and a mass spectrometer (LC-MS or GC-MS). With Direct MS, the labor-intensive sample preparation in the lab and separation using chromatography are bypassed. Instead, the sample is simply held directly in front of the inlet of a mass spectrometer. The sample can thus be „sniffed“ at atmospheric pressure.
A Whole Universe of New Possibilities
This not only saves a tremendous amount of time and personnel but also unveils a universe of new applications. Consider, for instance, container safety, drug detection, explosive checks, food inspections, or medical applications such as breath analyses or the identification of infections for targeted antibiotic administration. In conventional medical analytics, swabs or blood samples must currently be taken, processed extensively, and then analyzed. Direct MS enables the real-time identification of diseases. However, if it were as straightforward as it sounds, you would have probably heard of it by now. Because what sounds so promising in theory also comes with its fair share of challenges.
Still Work to Do
Most mass spectrometers are bulky and highly sensitive, which currently makes them unsuitable for field use. The standard method known in the 2000s using the Direct Analysis in Real Time (DART) ion source has the disadvantage of often being operated with helium, requiring the logistics and handling of a gas cylinder in addition to the MS. Not to mention the costs and availability of this noble gas (read also: Helium Shortage: Hydrogen as an Alternative Carrier Gas with Benefits on Top) Quantifying substances also presents current difficulties, and handling volatile, gaseous samples is nearly impossible with this method.
What is needed is a portable and robust MS and a versatile ion source that provides quantifiable data for solid, liquid, and gaseous substances. SICRIT® and HaVoc® address these challenges for Direct MS.
Ready to Sniff
The capability of SICRIT® has already been proven in various use cases in App Notes and Papers on Direct MS. Now, it’s only a matter of expanding the universe of application possibilities and establishing Direct MS in laboratories and field operations. This could save laboratories an immense amount of time, set a new standard for food safety, and simplify and expedite medical diagnostics significantly.