Examination of the Surface of a Maldi-Ftms Probe Tip using SEM and Determination of Detection Limits for Poly(Ethylene Glycol)

Exploratory synthetic strategies may yield limited quantities of sample. Characterization of such limited-quantity samples is facilitated by the use of sensitive analytical methods and smart sample preparation. Polymers may be analyzed by mass spectrometry for molecular weight distributions, structural information (such as endgroups), and impurities. However, polymer research using mass spectrometry has not focused on detection limits; in some work the amount of polymer used is not even mentioned. Studies to determine detection limits of polymers and studies that characterize sample preparation techniques can provide valuable information.Examination of the sample surface on a probe tip, generated by the use of an aerospray technique for sample deposition, was accomplished by scanning electron microscopy (SEM). Aerospraying the polymer and matrix solutions allowed signal averaging of mass spectra from up to 400 shots on the same sample spot. SEM images showed the surface of the probe to have a fairly uniform coating of the sample and matrix.

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Organic Solvent Traces in Fibrillar Scaffolds for Tissue Engineering

Journal of Biomimetics Biomaterials and Tissue Engineering ◽

10.4028/www.scientific.net/jbbte.7.1 ◽

2010 ◽

Vol 7 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

A. Lederer ◽

C. Harnisch ◽

Debes Bhattacharyya ◽

S. Fakirov

Keyword(s):

Mass Spectrometry ◽

Tissue Engineering ◽

Organic Solvent ◽

Glycolic Acid ◽

Ethylene Terephthalate ◽

Detection Limits ◽

Initial Amount ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

In the present study the amount of xylene remaining in fibrillar scaffolds after their manufacture has been estimated by means of Gas Chromatrography coupled to Mass Spectrometry (GC-MS). For this purpose model scaffolds of poly(ethylene terephthalate) (PET) comprised of microfibrils with diameters of ~1 µm or nanofibrils with diameters of 50-150 nm as well as microfibrillar scaffolds of poly(glycolic acid) (PGA) have been used. An extremely low initial amount of xylene has been found (< 20 ppm). The xylene amount dropped below 2 ppm after drying for 24 h in a vacuum at 80°C. The microfibrillar PGA scaffolds, initially containing more xylene (23.4 ppm), retained only 3.6 ppm after drying for 24 h. After drying for 48 h the amount of xylene in all the scaffolds studied reached the detection limits of the GC-MS apparatus (< 0.5 ppm).

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Combination of Time-of-Flight Mass Analysers with Magnetic-Sector Instruments: In-Line and Perpendicular Arrangements. Applications to Poly(Ethylene Glycol) with Long-Chain end Groups

European Journal of Mass Spectrometry ◽

10.1255/ejms.341 ◽

2000 ◽

Vol 6 (2) ◽

pp. 225-232 ◽

Cited By ~ 17

Author(s):

Andrew R. Botrill ◽

Anastassios E. Giannakopulos ◽

Allen Millichope ◽

Ken S. Lee ◽

Peter J. Derrick

Keyword(s):

Mass Spectrometry ◽

Ethylene Glycol ◽

Secondary Ion Mass Spectrometry ◽

Structural Information ◽

Orthogonal Experiment ◽

Time Of Flight ◽

High Energy ◽

Poly Ethylene Glycol ◽

End Groups ◽

Poly Ethylene

High-energy collision-induced dissociation has been shown to provide extensive and detailed structural information on poly(ethylene glycol) with palmitoyl end-groups. Fragmentation within the end-groups provides direct information on their structures. Both in-line time-of-flight (TOF) and orthogonal TOF have been used for the measurement of fragment ions. Use of TOF as the second stage of mass spectrometry has facilitated exploitation of the pulsed method of ionisation matrix-assisted laser desorption/ionisation (MALDI). The orthogonal TOF instrument is used with a liquid secondary-ion mass spectrometry source. The laboratory-frame collision energies were different for in-line and orthogonal TOF, being 8–12 keV in the former and 800 eV in the latter. The tandem mass spectra were similar for the in-line experiment with either He or Xe collision gas and the orthogonal experiment with Xe. Mechanisms proposed for the fragmentations involve homolytic cleavage (C–H and backbone bonds) and invoke non-ergodicity.

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Detection limits of matrix-assisted laser desorption/ionisation mass spectrometry coupled to chromatography - a new application of solvent-free sample preparation

Rapid Communications in Mass Spectrometry ◽

10.1002/rcm.2256 ◽

2005 ◽

Vol 19 (24) ◽

pp. 3724-3730 ◽

Cited By ~ 21

Author(s):

Jana Falkenhagen ◽

Steffen M. Weidner

Keyword(s):

Mass Spectrometry ◽

Sample Preparation ◽

Detection Limits ◽

Laser Desorption ◽

Solvent Free ◽

Free Sample ◽

Ionisation Mass Spectrometry ◽

Ionisation Mass ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

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Fundamentals of Sputtered Neutral Mass Spectrometry

MRS Bulletin ◽

10.1557/s0883769400067221 ◽

1987 ◽

Vol 12 (6) ◽

pp. 48-51 ◽

Cited By ~ 6

Author(s):

U. Kaiser ◽

J.C. Huneke

Keyword(s):

Mass Spectrometry ◽

Matrix Effects ◽

Detection Limits ◽

Isotopic Analysis ◽

Sample Surface ◽

Depth Profiles ◽

Elemental Detection ◽

Concentration Depth Profiles

AbstractSputtered neutral mass spectrometry (SNMS) is a technique for elemental and isotopic analysis with excellent detection limits, with similar sensitivity for all elements and without substantial matrix effects. Particles sputter atomized from the sample surface are ionized and mass spectrometrically measured. Elemental detection limits are routinely 1–10 ppm, but can be as low as 1–10 ppb. Particular modes of SNMS enable the measurement of accurate concentration depth profiles with resolutions approaching 20 Å and the measurement of electrically insulating samples.

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Signal enhancement techniques for chromatography detection systems

Journal of Automatic Chemistry ◽

10.1155/s146392469700014x ◽

1997 ◽

Vol 19 (5) ◽

pp. 145-152 ◽

Cited By ~ 4

Author(s):

K. D. Jackson ◽

S. J. Walton ◽

D. Campbell

Keyword(s):

Mass Spectrometry ◽

Sample Preparation ◽

Ground Water ◽

Trace Analysis ◽

Detection Limits ◽

Analytical Techniques ◽

Cost Effective ◽

Detection Systems ◽

Chromatographic Techniques ◽

Lower Detection

The Environmental Protection Act has created a growing need for the measurement and assessment of trace emissions to the environment. This encompasses three main areas of ground, water and the atmosphere. The need to achieve lower emissions has placed a large burden on analytical techniques, particularly in the areas of trace analysis to ppb and ppt levels. Chromatographic techniques are widely used for assessment and measurement of emissions in all three areas. Enhanced detectors using mass spectrometry principles are available to lower detection limits, but these are expensive. Standard chromatography detectors can be used for trace analysis, but this often leads to extensive sample preparation stages to achieve low detection limits. This paper describes the techniques developed by Thomas Swan & Company to introduce a cost effective way of lowering detection limits. The approach taken meets both BATNEEC and BPEO constraints.

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Applications of Time-OF-Flight Secondary Ion Mass Spectrometry (TOF-SIMS)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135149 ◽

1990 ◽

Vol 48 (2) ◽

pp. 308-309

Author(s):

Bruno Schueler ◽

Robert W. Odom

Keyword(s):

Mass Spectrometry ◽

Secondary Ion Mass Spectrometry ◽

Structural Information ◽

Time Of Flight ◽

Biological Tissues ◽

Polymer Surfaces ◽

Tof Sims ◽

Secondary Ions ◽

Ion Mass Spectrometry ◽

Secondary Ion

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) provides unique capabilities for elemental and molecular compositional analysis of a wide variety of surfaces. This relatively new technique is finding increasing applications in analyses concerned with determining the chemical composition of various polymer surfaces, identifying the composition of organic and inorganic residues on surfaces and the localization of molecular or structurally significant secondary ions signals from biological tissues. TOF-SIMS analyses are typically performed under low primary ion dose (static SIMS) conditions and hence the secondary ions formed often contain significant structural information.This paper will present an overview of current TOF-SIMS instrumentation with particular emphasis on the stigmatic imaging ion microscope developed in the authors’ laboratory. This discussion will be followed by a presentation of several useful applications of the technique for the characterization of polymer surfaces and biological tissues specimens. Particular attention in these applications will focus on how the analytical problem impacts the performance requirements of the mass spectrometer and vice-versa.

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Rapid Online Buffer Exchange: A Method for Screening of Proteins, Protein Complexes, and Cell Lysates by Native Mass Spectrometry

10.26434/chemrxiv.8792177 ◽

2019 ◽

Author(s):

Zachary VanAernum ◽

Florian Busch ◽

Benjamin J. Jones ◽

Mengxuan Jia ◽

Zibo Chen ◽

...

Keyword(s):

Mass Spectrometry ◽

High Speed ◽

Structural Information ◽

Protein Complexes ◽

High Sensitivity ◽

Native Mass Spectrometry ◽

Structural Features ◽

Consumer Products ◽

Cell Lysates ◽

Protein Expression And Purification

It is important to assess the identity and purity of proteins and protein complexes during and after protein purification to ensure that samples are of sufficient quality for further biochemical and structural characterization, as well as for use in consumer products, chemical processes, and therapeutics. Native mass spectrometry (nMS) has become an important tool in protein analysis due to its ability to retain non-covalent interactions during measurements, making it possible to obtain protein structural information with high sensitivity and at high speed. Interferences from the presence of non-volatiles are typically alleviated by offline buffer exchange, which is timeconsuming and difficult to automate. We provide a protocol for rapid online buffer exchange (OBE) nMS to directly screen structural features of pre-purified proteins, protein complexes, or clarified cell lysates. Information obtained by OBE nMS can be used for fast (<5 min) quality control and can further guide protein expression and purification optimization.

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