著者

Lee Chuin Chen Kentaro Yoshimura Satoshi Ninomiya Sen Takeda Kenzo Hiraoka

出版者

The Mass Spectrometry Society of Japan

雑誌

Mass Spectrometry (ISSN:2187137X)

巻号頁・発行日

vol.6, no.3, pp.S0070-S0070, 2017-08-25 (Released:2017-08-23)

参考文献数

42

被引用文献数

2

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In this paper, we briefly review the remote mass spectrometric techniques that are viable to perform “endoscopic mass spectrometry,” i.e., in-situ and in-vivo MS analysis inside the cavity of human or animal body. We also report our experience with a moving string sampling probe for the remote sample collection and the transportation of adhered sample to an ion source near the mass spectrometer. With a miniaturization of the probe, the method described here has the potential to be fit directly into a medical endoscope.

著者

Dilshadbek Tursunbayevich Usmanov Satoshi Ninomiya Lee Chuin Chen Subhrakanti Saha Mridul Kanti Mandal Yuji Sakai Rio Takaishi Ahsan Habib Kenzo Hiraoka Kentaro Yoshimura Sen Takeda Hiroshi Wada Hiroshi Nonami

出版者

The Mass Spectrometry Society of Japan

雑誌

Mass Spectrometry (ISSN:2187137X)

巻号頁・発行日

vol.6, no.2, pp.S0059-S0059, 2017-02-24 (Released:2017-02-24)

参考文献数

89

被引用文献数

9

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In mass spectrometry, analytes must be released in the gas phase. There are two representative methods for the gasification of the condensed samples, i.e., ablation and desorption. While ablation is based on the explosion induced by the energy accumulated in the condensed matrix, desorption is a single molecular process taking place on the surface. In this paper, desorption methods for mass spectrometry developed in our laboratory: flash heating/rapid cooling, Leidenfrost phenomenon-assisted thermal desorption (LPTD), solid/solid friction, liquid/solid friction, electrospray droplet impact (EDI) ionization/desorption, and probe electrospray ionization (PESI), will be described. All the methods are concerned with the surface and interface phenomena. The concept of how to desorb less-volatility compounds from the surface will be discussed.

著者

Yuki Yamada Satoshi Ninomiya Kenzo Hiraoka Lee Chuin Chen

出版者

The Mass Spectrometry Society of Japan

雑誌

Mass Spectrometry (ISSN:2187137X)

巻号頁・発行日

vol.5, no.2, pp.S0068-S0068, 2017-04-18 (Released:2017-04-27)

参考文献数

23

被引用文献数

5

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We report on combining a self-aspirated sampling probe and an ESI source using a single metal capillary which is electrically grounded and safe for use by the operator. To generate an electrospray, a negative H.V. is applied to the counter electrode of the ESI emitter to operate in positive ion mode. The sampling/ESI capillary is enclosed within another concentric capillary similar to the arrangement for a standard pneumatically assisted ESI source. The suction of the liquid sample is due to the Venturi effect created by the high-velocity gas flow near the ESI tip. In addition to serving as the mechanism for suction, the high-velocity gas flow also assists in the nebulization of charged droplets, thus producing a stable ion signal. Even though the potential of the ion source counter electrode is more negative than the mass spectrometer in the positive ion mode, the electric field effect is not significant if the ion source and the mass spectrometer are separated by a sufficient distance. Ion transmission is achieved by the viscous flow of the carrier gas. Using the present arrangement, the user can hold the ion source in a bare hand and the ion signal appears almost immediately when the sampling capillary is brought into contact with the liquid sample. The automated analysis of multiple samples can also be achieved by using motorized sample stage and an automated ion source holder.

著者

Kenzo Hiraoka Yuji Sakai Hiroyuki Kubota Satoshi Ninomiya Stephanie Rankin-Turner

出版者

The Mass Spectrometry Society of Japan

雑誌

Mass Spectrometry (ISSN:2187137X)

巻号頁・発行日

vol.12, no.1, pp.A0114, 2023-01-31 (Released:2023-01-31)

参考文献数

35

被引用文献数

1

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Among the various types of cluster secondary ion mass spectrometry (SIMS), electrospray droplet impact/secondary ion mass spectrometry (EDI/SIMS) is unique due to its high ionization efficiency and non-selective atomic/molecular-level surface etching ability. In this study, EDI/SIMS was applied to the non-selective etching of synthetic polymers of polystyrene (PS) and poly(9,9-di-n-octylfluonyl-2,7diyl) (PFO) deposited on a silicon substrate. The polymers gave characteristic fragment ions and the mass spectra remained unchanged with prolonged EDI irradiation time, indicating that non-selective etching can be achieved by EDI irradiation, a finding that is consistent with our previous reports based on EDI/X-ray photoelectron spectroscopy analyses. From the irradiation time and film thickness, the etching rates for PS and PFO were roughly estimated to be 0.6 nm/min and 0.15 nm/min, respectively, under the experimental conditions that were used. After the depletion of polymer sample on the surface, ion signals originating from the exposed silicon substrate were observed. This indicates that EDI/SIMS is applicable to the analysis of the interface of multilayered films composed of organic and inorganic materials.

著者

Kenzo Hiraoka Osamu Ariyada Dilshadbek T. Usmanov Lee C. Chen Satoshi Ninomiya Kentaro Yoshimura Sen Takeda Zhang Yu Mridul K. Mandal Hiroshi Wada Stephanie Rankin-Turner Hiroshi Nonami

出版者

The Mass Spectrometry Society of Japan

雑誌

Mass Spectrometry (ISSN:2187137X)

巻号頁・発行日

vol.9, no.1, pp.A0092, 2020-12-04 (Released:2020-12-04)

参考文献数

61

被引用文献数

17

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In 2007, probe electrospray ionization/mass spectrometry (PESI/MS) was developed. In this technique, the needle is moved down along a vertical axis and the tip of the needle touched to the sample. After capturing the sample at the needle tip, the needle is then moved up and a high voltage is applied to the needle at the highest position to generate electrospray. Due to the discontinuous sampling followed by the generation of spontaneous electrospray, sequential and exhaustive electrospray takes place depending on the surface activity of the analytes. As modified versions of PESI, dipping PESI (dPESI), sheath-flow PESI (sfPESI) and adjustable sfPESI (ad-sfPESI) have been developed. These methods are complementary to each other and they can be applicable to surface and bulk analysis of various biological samples. In this article, the characteristics of these methods and their applications to real samples will be reviewed.