著者

吉野 健一

出版者

The Mass Spectrometry Society of Japan

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.56, no.2, pp.69-76, 2008-04-01

参考文献数

7

被引用文献数

1

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The Japanese word "mirimasu" originates from the English words "milli" and "mass." It is normally used as an alias for "measured accurate mass" and "accurate mass measurement." It causes confusions that "mirimasu" is also used as an alias for "high resolution mass spectrometry," "high resolution mass spectrum (spectra)," and "mass spectrometer with high mass resolving power." This nomenclature results from the fact that "high resolution" is confused with "high accuracy." In addition to these interpretations, Japanese mass spectrometrists also use "mirimasu" as an alias for "one-thousandth of a unified atomic mass unit," "one-thousandth of a dalton (mDa)," and "one-thousandth of an <i>m/z</i> unit." This incorrect usage is due to a lack of understanding of the unit system of atomic mass and <i>m/z</i> on mass spectra. Therefore, "mirimasu" should not be used in Japanese, because it is ambiguous and involves various problems and misunderstandings.

著者

吉野 健一

出版者

The Mass Spectrometry Society of Japan

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.56, no.6, pp.269-274, 2008-12-01

被引用文献数

1

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The unified atomic mass unit (unit symbol: u) is a non-SI unit of mass, defined as one-twelfth the mass of a single ¹²C atom in its ground state. [SI: Le Système International d'Unités; The International System of Units] This definition was agreed upon by both the International Union of Pure and Applied Physics (IUPAP) and the International Union of Pure and Applied Chemistry (IUPAC) in the early 1960s to resolve a longstanding difference between two scales of the atomic mass unit. The term "atomic mass unit" (unit symbol: amu) has been used as a unit of mass defined as one-sixteenth the mass of a single atom ¹⁶O [<i>m</i>(¹⁶O)=16 amu] in physics and as one-sixteenth the isotope-averaged atomic mass (equivalent to the atomic weight) of oxygen [<i>A</i>_r(O)=16 amu] in chemistry.<br>The unit dalton (unit symbol: Da) is also a non-SI unit of mass defined as "1 Da=1 u," and is accepted as a unit for use by the SI in the 8th edition of the SI brochure (2006). Therefore, both the unified atomic mass unit and dalton are authorized units for mass of ions and molecules. <br>It is a common mistake to use the deprecated term "atomic mass unit" and the deprecated unit symbol "amu" for the unit of mass defined as one-twelfth the mass of single atom ¹²C. The unit symbol "mmu," meaning a millimass unit, is also an appropriate unit in SI. Instead of "mmu," "mDa" or and "10^-3 u" should be used.

著者

田中 耕一

出版者

日本質量分析学会

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.45, no.1, pp.113-121, 1997-02-01

著者

渋江 俊道 ウォン カイティ グロス マイケル

出版者

The Mass Spectrometry Society of Japan

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.48, no.3, pp.221-227, 2000-06-01

参考文献数

20

被引用文献数

3

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We developed an assay method that utilizes ESI and ion trap mass spectrometry to rapidly determine the binding nature of drugs with oligodeoxynucleotides and to assess their relative affinities, stoichiometries and specificities in non-covalent interactions. Selectivity experiments show that the drugs H₂TMpyP and CuTMpyP bind <I>via</I> mixed modes, whereasFeTMpyP and MnTMpyP interact by groove binding only. Competitive binding experiments show that the order for the drugs with duplex 5′ATATAT3′ was H₂TMpyP-CuTMpyP>FeTMpyP-MnTMpyP. We also investigated the gas-phase stability of duplex oligodeoxynucleotides and the non-covalent complexes by monitoring the dissociation profiles of those non-covalent associations as a function of collision energy in the ion-trap mass spectrometer. We defined a half-wave collision energy which corresponds to the collision energy (in percentage of the maximum tickling voltage) at which the relative abundance of the complex ion had dropped to 50% and used this as an estimate of the gas-phase stability. The gas-phase stability of double-stranded oligonucleotide correlates with the number of H-bonds within the duplex. The noncovalent complexes of the drugs (Distamycin A, Actinomycin D, and Mn(III)TMpyP) and the duplex oligonucleotides are more stable in the gas phase than the duplexes themselves.

著者

Yoon Boo Ok Koyanagi Shin Asano Takao HARA Mariko HIGUCHI Akon

出版者

The Mass Spectrometry Society of Japan

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.51, no.1, pp.168-173, 2003-02-01

被引用文献数

1 2

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We undertook a fundamental investigation of the removal of endocrine disruptors from aqueous solution by a sorption method using activated carbons, and compared the removal ability of endocrine disruptors by activated carbons to that by polydimethylsiloxane (PDMS) membranes. The activated carbons exhibited high removal ability of 1,2-dibromo-3-chloropropane (DBCP), 100 fold increased adsorption over that with PDMS membranes from aqueous solution of DBCP. The removal ratio of the endocrine disruptors, <i>e.g., </i>1,2-dibromo-3-chloropropane, dibenzo-<i>p</i>-dioxin, and hexachlorocyclohexane, increased linearly in an aqueous solution with increasing the logarithm of <i>P</i>_ow of the endocrine disruptors. Almost complete removal of the endocrine disruptors (<i>i.e.,</i>>85%) was observed above log <i>P</i>_ow=3.5 in 25 mL of an aqueous solution using 0.05 g activated carbon. One aim of the present study is to use preferential sorption of chemical contaminants onto activated carbons for removal of the chemical contaminants from aqueous solutions including drinking water, beverages, milk, and human milk. When the removal of endocrine disruptors contained in milk or human milk is targeted, water soluble vitamins in the milk, such as vitamin B₂, vitamin B₁₂, and niacin are expected to be co-currently adsorbed on the activated carbons. Therefore, the present sorption method using activated carbon was applied to the removal of endocrine disruptors, such as di-<i>n</i>-octylphthalate, from the mineral water and 89% of di-<i>n</i>-octylphthalate was removed.

著者

長友 健治

出版者

The Mass Spectrometry Society of Japan

雑誌

質量分析 = Mass spectroscopy (ISSN:13408097)

巻号頁・発行日

vol.54, no.5, pp.194-195, 2006-10-01

被引用文献数

1