Radiant energy – Ionic separation or analysis – With sample supply means
Reexamination Certificate
2003-10-27
2004-11-09
Lee, John R. (Department: 2881)
Radiant energy
Ionic separation or analysis
With sample supply means
C250S281000, C250S282000
Reexamination Certificate
active
06815672
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a method of analyzing polymer using laser ablation and system therefor, more particularly to the method of analyzing polymer using laser ablation and system therefor, which are capable of significantly improving the efficiency of analysis comparing with a conventional ones, and the invention relates to the method of analyzing polymer using laser ablation and system therefor, which are preferably used in mass analysis of various kinds of polymer such as DNA, protein, RNA, PNA, lipid, sugar and the like, for example.
BACKGROUND ART
In recent years, the application range of the mass analysis has rapidly spread from the field of physics and chemistry to the field of life science such as medical science and biochemistry. Particularly, its development in decision calculus of protein molecular weight and decision calculus of amino-acid sequence is astonishing.
The principle of such mass analysis is that a sample is ionized by various kinds of method, ions obtained by ionization are separated according to mass/charge, and the intensity of each separated ion is measured.
Incidentally, conventional mass analysis for polymer has been the one that electron was added to the polymer itself to ionize it, its mass was analyzed or a molecule of high molecular weight was fragmented into molecular ions of low molecular weight to perform mass analysis, and constituent molecules were compared.
Herein, as an ion generating method in the conventional mass analysis of polymer, a secondary ion mass spectrometry (SIMS) where high-energy atomic ions are made to collide with polymer to cause ionization, an electron desorption ionization (ED) where the molecule is fragmented into the molecular ions of low molecular weight by electron impact, a matrix-assisted laser desorption ionization (MALDI), and the like are known, for example.
However, all of the above-described methods have had problems that they needed a mass spectrograph having high resolving power to perform mass analysis to polymeric ion and that the existence of fragment ions, which were decomposed/generated halfway, made the analysis of mass spectrum difficult.
On the other hand, as mass analysis method for a polymer sample labeled by isotope in performing chemical analysis, a laser atomization resonance ionization microprobe (LARIMP) where a nano-second laser performs atomization and ionization has been conventionally known.
However, according to the LARIMP method, two lasers that are an atomization laser to atomize a labeled element and a resonance ionization laser to ionize the atoms of the atomized labeled element are required as the laser, there has been a problem that the system configuration became complicate.
Moreover, resonance ionization needs to be performed to the labeled atoms in the LARIMP method as described above. For this reason, it is necessary to irradiate laser beams having a unique wavelength to each labeled atom, and there has been a problem that it was quite difficult to perform efficient analysis in the case where various kinds of labeled isotope were mixed.
The present invention has been invented in consideration of the various kinds of above-described problems that the prior art has, and its object is to provide the method of analyzing polymer using laser ablation and system therefor, which generate the atomic ions of constituent atoms that constitute polymer and analyze the generated atomic ions, and the mass analysis method for polymer using laser ablation and system therefor, which do not require a spectrograph of high resolving power. More specifically, the object is to provide the mass analysis method for polymer using laser ablation and system therefor, which eliminate a chance where the analysis of mass spectrum becomes difficult and where the mass spectrograph does not require high resolving power, in the case of performing mass analysis, for example.
Further, the object of the present invention is to provide the method of analyzing polymer using laser ablation and system therefor, which enables single laser to simultaneously realize atomization and ionization of the constituent atoms that constitute polymer, and to drastically simplify the system configuration.
Furthermore, the object of the present invention is to provide the method of analyzing polymer using laser ablation and system therefor, which are capable of performing efficient analysis even in the state where various kinds of labeled isotope are mixed.
DISCLOSURE OF INVENTION
To achieve the above-described objects, the present invention is one that the ultra-short pulse laser beams perform ablation to various kinds of polymers such as DNA, protein, RNA, PNA, lipid, sugar and the like, for example, the polymers are transferred into atomic ions to generate atomic ions, and the generated atomic ions are analyzed. With this configuration, the chemical analysis for various kinds of polymers can be performed.
Specifically, according to the present invention, by performing laser ablation to polymer by the ultra-short pulse laser beams, the polymer is decomposed in pieces and atomized by each of atoms that constitute the polymer, and the atomized atoms are ionized into univalent ions, and quantitative analysis can be performed by analyzing the atomic ions generated by the ionization.
Therefore, when performing mass analysis in the present invention, mass analysis is performed to the atomic ions of low mass, which eliminates the chance where the analysis of mass spectrum becomes difficult. The mass spectrograph does not require high resolving power.
Further, as described above, according to the present invention, by performing ablation to polymer by the ultra-short pulse laser, the ionization of atomized atoms into univalent ions can be efficiently performed simultaneously with the atomization of polymer. Therefore, the system configuration can be simplified, various kinds of labeled elements can be simultaneously used in performing chemical analysis, and thus analysis efficiency can be improved.
In the present invention, since the single ultra-short pulse laser can simultaneously atomize and ionize labeled elements, the system configuration can be drastically simplified.
Moreover, since the above-described ionization is ionization (non-resonance ionization) performed by high peak power intensity of the ultra-short pulse laser beams via non-resonant process, each labeled atom can be ionized even in the state where various kinds of labeled isotopes are mixed, it can be easily applied to a multi-label system, and highly accurate and highly efficient polymeric analysis can be performed.
Thus, the present invention is extremely preferable for the use in the quantitative analysis for gene expression, which will be increasingly important in future.
Specifically, the present invention is the method of analyzing polymer using laser ablation, where polymer is atomized into constituent elements by irradiating laser beams on the polymer, which is the analyzing subject, to perform ablation to the polymer, the atomized constituent elements are ionized, and the ionized constituent elements are thus analyzed, wherein the laser beams irradiated on the polymer, which is the analyzing subject, to perform ablation to the polymer are the ultra-short pulse laser beams, in which the polymer is simultaneously atomized into constituent elements and ionized by irradiating the ultra-short pulse laser beams on the polymer, which is the analyzing subject, to perform ablation to the polymer, and the ionized constituent elements are analyzed.
Herein, mass analysis can be cited as the above-described analysis, for example, and chemical analysis (so-called regular chemical analysis) or optical analysis (such as a fluorescence method), for example, is cited as analysis other than the mass analysis.
Further, in the present invention, the polymer that is the analyzing subject may be one transformed into solid phase (dry phase).
Furthermore, in the present invention, a method of transforming polymer into solid phase may be a method that include
Hayashizaki Yoshihide
Tanihata Isao
Gill Erin-Michael
Lee John R.
Riken
LandOfFree
Method of analyzing polymer by using laser abrasion and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of analyzing polymer by using laser abrasion and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of analyzing polymer by using laser abrasion and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3345833