Mass spectrometry, or MS, measures the mass-to-charge ratio of molecules in four main phases: ionization, acceleration, deflection, and detection. Lab technicians and researchers use a sophisticated MS bench featuring various instruments and tools.
Here is an overview of five tools used in mass spectrometry:
1. Ion Source
Mass spectrometry involves plotting the ions of varying masses on a spectrum. Before the results are displayed on a mass spectrum graph, the sample has to be ionized. This process begins with the lab technician determining the sample size. The sample is then placed into the inlet of the ion source. The sample then passes through the ionizer.
Ionization is accomplished using an electron source that beams high-energy electrons between a cathode and anode. The electrons move at a high speed, bombarding the sample. This constant bombarding knocks electrons out of the molecule to form ions. Lab technicians can achieve hard or soft ionization, depending on the test’s goals.
The ions produced by the ion source are then accelerated through a set of charged parallel plates. Ions attracted to one plate repel from the other. Lab technicians can control acceleration speed by adjusting the charge on the plates. The accelerator draws ions through magnetic or electrical fields, separating them into fragments. Ion separation is achieved by the process of deflection.
Heavy ions and those with two or more positive charges deflect the least. Light ions and those with one positive charge deflect the most. This separation allows the lab technician to measure the fragmented ions using a mass analyzer. Analysis technology generates digital conversions for the detector, which makes it possible to view the results on a monitor.
The detector is the final instrument within a mass spectrometer. Ions bending from the ionizer and into the accelerator and deflector then move toward the detector. The detector allows the lab technician to collect mass-to-charge ratio data. The detector can also record the charge or current induced by passing ions. Detectors can distinguish the charged particles and generate a mass spectrum.
Most mass spectrometer systems feature a computer to save incoming data more efficiently. The computers provide a comprehensive analysis, reducing the need for lab technicians to complete manual transcription. Lab technicians then use the results to identify atoms and molecules present in the sample.
4. Vacuum System
Mass spectrometers use high vacuum to reduce the chances of charged ions colliding with other molecules in the analyzer. Collisions can cause the ions to scatter, react, neutralize, or fragment, interfering with the final spectrum produced. Lab technicians achieve high vacuum conditions using two types of pumps, mechanical and diffusion.
Mechanical pumping is the first stage of creating a vacuum and produces rough vacuum. Diffusion or turbomolecular pumps are used in the second stage to produce high vacuum. Some MS systems feature cryogenic pumps for a third pumping stage. The goal of the vacuum is to keep ions intact as they travel from the ionizer to the detector.
Many modern MS bench systems feature computer monitors on flexible arms to expand the function of the space. Computer interfaces allow the lab technician to design and complete measurement schedules. They also help lab technicians record data more accurately.
Computers created specifically for the mass spectrometry industry can store the spectra of thousands of molecules. This makes rapid sample identification during a study possible. These computers can also generate accurate conclusions and answer study questions instantly.
Comprehensive MS Bench Setups
Mass spectrometry uses various tools in a single unit for seamless analysis. Lab technicians can purchase MS bench setups designed to accommodate those mass spectrometry tools. These specialized benches commonly feature work surfaces, noise-suppressing pump enclosures, exhaust fans, CPU holders, surge suppressors, monitor stands, and more. You can also find MS tables and benches that are customizable to meet your lab’s needs.