JEOL Resources

AccuTOF DART Applications Notebook

Wed, 10 Mar 2021 15:37:05 GMT

Notebook containing various articles and application notes pertaining to the AccuTOF DART.

Download using the link below.

Direct Analysis in Real Time (DART®) Mass Spectrometry

Fri, 13 Mar 2020 16:11:22 GMT

Atmospheric pressure ion sources such as atmospheric pressure chemical ionization(APCI)[5], electrospray ionization (ESI)[6-8],matrix-assisted laser desorption ionization(MALDI)[9-10] and atmospheric pressure photoionization (APPI)[11] have broadened the range of compounds that can be analyzed by mass spectrometry. However, these ion sources require that samples be exposed to elevated temperatures and electrical potentials,ultraviolet irradiation, laser radiation, or a high-velocity gas stream. Safety considerations require that the ion source be fully enclosed to protect the operator from harm.

The new ion source reported herein overcomes these limitations. The new technique, referred to as Direct Analysis in Real Time(DART™), has been coupled to the AccuTOF-LC™ atmospheric pressure ionization mass spectrometer to permit high-resolution, exact mass measurements of gases, liquids, and solids[12,13]. DART successfully sampled hundreds of chemicals, including chemical agents and their signatures, pharmaceutics,metabolites, pesticides and environmentally significant compounds, peptides and oligosaccharides, synthetic organics, organometallics, drugs of abuse, explosives, and toxic industrial chemicals. These chemicals were detected on a variety of surfaces such as concrete, human skin, currency, airline boarding passes, fruits and vegetables, body fluids, cocktail glasses,and clothing. The composition of drug capsules and tablets was directly analyzed.

AccuTOF™ DART® Product Brochure

Fri, 06 Mar 2020 06:56:13 GMT

Direct Analysis with Time-of-Flight MS

AccuTOF-DART® is the perfect union of a time-of-flight mass spectrometer and an open air ion source. The DART ion source fully utilizes the speed and accuracy of the AccuTOF for small molecule analysis, producing clean, reproducible, easy-to-interpret data.

Real Time Analysis

AccuTOF-DART has completely changed the field of mass spectrometry. Now you can immediately determine chemical composition of knowns and unknowns, and produce high-resolution, accurate mass spectra by simply placing a sample, in its native form, between the DART ion source and the AccuTOF mass spectrometer inlet.

Wide Analytical Range

No interface is required between the DART and the MS, therefore the AccuTOF-DART is able to detect a wider range of polar and nonpolar compounds than any other ambient mass spec system.

Award-winning Technology

JEOL introduced the DART ion source in 2005, and the technology quickly gained recognition, winning both the Pittcon Editor’s Gold Award and the R&D 100 Award. Since that time nearly 400 papers have been published by chemists using the AccuTOF-DART. The introduction of DART made it possible for the first time to carry out atmospheric pressure ionization for analysis of samples in open air.

Accurate Isotope Data is Essential for Determining Elemental Compositions

Wed, 04 Mar 2020 17:28:19 GMT

Elemental compositions are commonly determined from high-resolution mass spectra and accurate mass measurements. Given a measured mass (m/z) and a range of elements that can be present, software calculates the exact mass for each combination of elements and reports all elemental combinations that match the measured mass within a specified error tolerance. Improving the mass accuracy reduces the number of elemental compositions, but mass accuracy alone may not be sufficient to determine the correct elemental composition for an unknown sample. JEOL AccuTOF™ mass spectrometers (the AccuTOF™-DART®, the AccuTOF™-GCX and the AccuTOF™-GCX Plus) are capable of accurate isotope measurements that can be used to determine elemental compositions from high-resolution mass spectra. Matching the measured abundances and exact masses for isotope peaks can be more effective than mass accuracy alone.

The AccuTOF™-DART® 4G: The Ambient Ionization Toolbox™

Sun, 23 Feb 2020 10:29:37 GMT

JEOL introduced the AccuTOF-DART in 2005 as the first commercially available ambient ionization mass spectrometer system. The atmospheric pressure ionization interface (API) for the AccuTOF system, originally designed as a simple, rugged and reliable LC/MS interface, became the ideal platform for developing the Direct Analysis in Real Time (DART) ion source. Because the DART ion source can be positioned directly in front of the AccuTOF sampling orifice without additional interface hardware, a variety of ambient ionization techniques are available to the AccuTOF-DART operator without removing the DART ion source. The third-generation AccuTOF-DART 4G system is an “ambient ionization toolbox” that allows the analyst to choose ionization methods that are best matched to the samples to be analyzed.

The AccuTOF® Atmospheric Pressure Interface: an Ideal Configuration for DART® and Ambient Ionization

Sun, 23 Feb 2020 10:21:11 GMT

The AccuTOF API

Figure 1 shows a schematic diagram of the AccuTOF atmospheric pressure interface. The API consists of two offaxis skimmers (designated “orifice 1” and “orifice 2”) with an intermediate ring lens, followed by a bent RF ion guide. The off-axis skimmer design traps contamination -- ions are electrostatically guided upward toward orifice 2 whereas neutral molecules are pumped downward. Any contamination that enters the API is either pumped away into the rough pump (RP) or trapped on the lower part of orifice 2. The bent RF ion guide provides an additional level of protection. This makes the AccuTOF an ideal mass spectrometer for DART analysis of dirty “real-world” samples such as mud, biological fluids, melted chocolate, polymers, and even crude oil. In addition, orifice 1 is easily accessible and is operated at low voltage and current, making it a convenient platform for ambient ionization sources.