TWI512782B - Ambient ionization device and system of thermogravimetry integrated with mass spectrometer using the same - Google Patents

Description

Atmospheric free device and thermogravimetric mass spectrometry system

The present invention relates to an atmospheric free device, and more particularly to an atmospheric free device incorporating different free sources, and a mass spectrometry system and mass spectrometry method using the atmospheric free device in combination with thermogravimetric analysis.

Polymers are closely related to daily life. In the process of synthesis and processing, the analysis of their structure, physical properties and chemical properties is an important part of quality management. However, prior to the analysis of the high molecular polymer, cumbersome pretreatment and separation are usually required to purify the target analyte, so that the chemical composition can be further identified by techniques such as spectroscopy or mass spectrometry. Due to the low volatility and solubility of the polymer itself, it is not possible to directly detect the free radical. Most of the literature is used with the pyrolyzer. The analyte is firstly cracked and gasified, and then imported into the meteorological mass spectrometer. (Gas Chromatography/Mass Spectrometry, GC/MS) was analyzed. Alternatively, most of the industry uses the Thermogravimetric Analyzer (TGA) to effectively monitor changes in material properties through the relationship between mass and temperature and mass spectrometry of fugitive gases. It can be seen from the above methods that the chemical composition of the high molecular weight polymer is very important for academic research and industrial mass production.

In mass spectrometry, the analyte must be freed to carry a charge, after which Imported into the mass spectrometer to output an analytical map according to its respective charge-to-mass ratio (ie, m/z value, referred to as mass-to-charge ratio, where m is mass, z is the number of charges carried), and the analyte is obtained by interpreting the analytical map. The molecular composition of the message. The method of application to the free mass spectrometer can be roughly classified into two types: the electron free method used in the early stage and the chemical free method which has been popularized in recent years. The signal generated by the electron-free method is mainly fragment ions, and the mass spectrum is extremely complicated, so it is difficult to determine the molecular weight of the analyte. Conversely, the chemical free method has a relatively small free energy compared to the electron free method, so that a higher proportion of the analyte ion signal can be obtained, and the proportion of the generated fragment ions is lower, so that a spectrum with a simple signal can be obtained. It is conducive to interpretation, so it is also called soft free method. In the soft free method, the currently known Electrospray ionization (ESI) can perform high-sensitivity analysis of polar samples under atmospheric pressure, and can make macromolecular compounds with multivalent charges and free, and The generated ions retain the original analyte structure intact and have the advantage of being soft free. Another soft free rule that can be operated at atmospheric pressure is the low temperature plasma free method, which is mainly for the analysis of low and medium polarity analytes. However, whether it is electrospray or low temperature plasma free, the molecular polarities applied have their own limits. That is to say, the application of electrospray is a sample of higher polarity. When the molecules of the analyte are not polar, it is not suitable to use the electrospray free method to free the analyte, and it is necessary to replace the suitable free source. Under this circumstance, for the analysis of compounds of unknown structure, it is necessary to repeat the analysis in different free manners several times, which takes time and cost, or may be misjudged due to the limitation of the free method.

Therefore, it is necessary to provide an atmospheric free device and a thermogravimetric mass spectrometry system, which can be applied to a wide range of molecular species analysis, and has a simple mass spectrometer signal to solve the problems in the conventional technology.

The main object of the present invention is to provide an atmospheric free device capable of simultaneously generating two or more kinds of free sources under atmospheric pressure, which is suitable for real-time analysis of a wide range of molecular species, and simplifies the mass spectrometer.

A secondary object of the present invention is to provide a thermogravimetric mass spectrometry system that utilizes the above-described atmospheric free device in combination with a thermogravimetric analysis device to provide free sources of various types of molecules, improve detection sensitivity, and save analysis time and cost.

In order to achieve the above object, an embodiment of the present invention provides an atmospheric free device comprising: an electric spray unit having a nozzle and a receiving portion, wherein the receiving portion is provided with an electrospray solution, wherein Applying a voltage to the electrospray solution away from the nozzle in the accommodating portion, the electrospraying solution passes through the nozzle to generate a first charged particle; a gas chamber for accommodating and circulating a gas, including a gas injection a discharge end is disposed in the gas passage; a first electrode portion is disposed outside the electric spray unit; and a second electrode portion is disposed at the gas chamber The outer side, wherein the first electrode portion and the second electrode portion are energized to form an electric field, the gas is converted into a second charged particle, and mixed with the first charged particle to form a composite free source.

In an embodiment of the invention, the electrospray unit is a capillary tube, and the nozzle is a nozzle of the capillary tube.

In an embodiment of the invention, the electrospray unit is disposed coaxially with the gas passage.

In an embodiment of the invention, the electrospray solution is a mixed solution of methanol, water and acetic acid.

In one embodiment of the invention, the gas system is dry air, helium, nitrogen or argon.

In an embodiment of the invention, the first electrode portion is a ground electrode, and the second electrode portion is a high voltage electrode.

In an embodiment of the invention, the first electrode portion is a metal tube having a tube body and an opening portion, the electric spraying unit is disposed through the tube body, and the nozzle portion exposes the opening portion.

In an embodiment of the invention, the second charged particle is a low temperature plasma.

Furthermore, another embodiment of the present invention provides a thermogravimetric mass spectrometry system comprising: an atmospheric free device as described above; a thermogravimetric analysis device for heating a test object to form a neutral molecule; And a mass spectrometry device having an ion inlet, wherein the composite free source and the neutral molecule first react with an ion molecule to form a charged molecule, and the charged molecule then enters the mass spectrometer from the ion inlet to analyze the charged molecule Mass to charge ratio.

In an embodiment of the invention, the thermogravimetric analysis device comprises a heating unit, a weight measuring unit and a gas output port to obtain a temperature-to-weight curve of the object to be tested.

In an embodiment of the invention, the gas outlet is disposed adjacent to the composite free source, and the neutral molecule enters the composite free source to react to form the charged molecule.

In one embodiment of the invention, the composite free source of the composite free device and the ion inlet of the mass spectrometry device are opposite each other.

1‧‧‧ Thermogravimetric Analysis Mass Spectrometry System

10‧‧‧Atmospheric free device

11‧‧‧Electrical spray unit

12‧‧‧ gas chamber

13‧‧‧First electrode section

14‧‧‧Second electrode section

15‧‧‧DC power generator

16‧‧‧AC power generator

17‧‧‧Conducting components

20‧‧‧ Thermogravimetric analysis device

30‧‧‧Mass Spectrometer

111‧‧‧Nozzles

112‧‧‧ 容部

121‧‧‧ gas injection end

122‧‧‧export end

123‧‧‧ gas passage

131‧‧‧pipe body

132‧‧‧ openings

201‧‧‧heating unit

202‧‧‧ Weight measuring unit

203‧‧‧ gas outlet

301‧‧‧Ion entrance

A‧‧‧Test object

A1‧‧‧ Neutral

A2‧‧‧ charged molecules

E1‧‧‧First charged particles

E2‧‧‧Second charged particles

I‧‧‧Complex free source

Fig. 1 is a schematic view showing an atmospheric free device according to an embodiment of the present invention.

Fig. 2 is a schematic view showing the combination of a thermogravimetric mass spectrometry system according to another embodiment of the present invention.

The above and other objects, features and advantages of the present invention will become more <RTIgt; Furthermore, the directional terms mentioned in the present invention, such as upper, lower, top, bottom, front, rear, left, right, inner, outer, side, surrounding, central, horizontal, horizontal, vertical, longitudinal, axial, Radial, uppermost or lowermost, etc., only refer to the direction of the additional schema. Therefore, the directional terminology used is for the purpose of illustration and understanding of the invention.

Referring to FIG. 1 , an atmospheric free device 10 according to an embodiment of the present invention mainly includes an electric spraying unit 11 , a gas chamber 12 , a first electrode portion 13 , and a second electrode portion 14 . DETAILED DESCRIPTION OF THE INVENTION The detailed construction, assembly relationship, and operation principle of the above-described respective elements of the atmospheric free device 10 will be described in detail below.

Referring to FIG. 1 again, the electric spraying unit 11 includes a nozzle 111 and a receiving portion 112. The receiving portion 112 can accommodate an electrospray solution, and is away from the receiving portion 112. A voltage is applied to the electrospray solution at the nozzle 111, and the electrospray solution is passed through the nozzle 111 to generate a first charged particle E1. The first charged particle E1 is a free source that can be used to free the analyte. The electric spraying unit 11 may be, for example, a capillary having a diameter of 800 μm or less, and may be, for example, 100, 250 or 750 μm, but is not limited thereto. The nozzle 111 is a nozzle of the capillary. The electric spraying unit 11 can also include a pump (not shown) for drawing the electric spraying solution to the receiving portion 112. The electrospray solution is a mixed solution comprising a polar solvent, water and an additive, and the polar solvent may be, for example, methanol, ethanol, isopropanol or acetonitrile, and the additive may be, for example, It is formic acid, acetic acid or ammonia, and the ratio is between 0.1 and 5%. Therefore, the electrospray solution may be, for example, a mixed solution of 49.5% methanol, 49.5% water, and 1% acetic acid; a mixed solution of 69.5% methanol, 39.5% water, and 1% formic acid; or 79.5% isopropanol, 29.5% water. A mixed solution with 1% formic acid. The voltage can be a DC voltage, for example, a conductive element 17 (such as a wire) is connected to the DC power generator 15 and then introduced into the side of the receiving portion 112 away from the nozzle 111. Other conductive means apply this voltage to the electrospray solution. Further, the voltage ranges from 2 kV to 5 kV and may be, for example, 3.5 kV.

Referring again to FIG. 1, the gas chamber 12 includes a gas injection end 121, an outlet end 122, and a gas passage 123. The gas chamber 12 can be, for example, a hollow column for circulating a gas, which can be made of glass or other dielectric material. Further, the electric spraying unit 11 is disposed in the gas passage 123. Preferably, the electric spraying unit 11 is disposed coaxially with the gas passage 123. For example, when the electric spraying unit 11 is a capillary tube and the gas chamber 12 is a hollow tubular string, the axial positions of the two are the same. The gas flows around the electric spraying unit 11, but is not limited thereto. The gas enters the gas chamber 12 through the gas injection end 121, which is a gas that can generate plasma, such as dry air, helium gas, nitrogen gas or argon gas, or is mixed with hydrogen gas or oxygen gas. Not limited to this.

The first electrode portion 13 is disposed on the outer side of the electric spraying unit 11, and may be a metal tube, such as a stainless steel tube, having a tube body 131 and an opening portion 132. The electric spraying unit is disposed in the middle. 11. Preferably, the nozzle 111 exposes the opening 132. The second electrode portion 14 is disposed outside the gas chamber 12, and may be, for example, a stainless steel ring. However, the second electrode portion 14 is not limited thereto, and may be a stainless steel piece. Therefore, the middle of the first electrode portion 13 and the second electrode portion 14 are separated by the gas chamber 12, and an electric field is formed after energization to make the gas flow flowing therein Upon this electric field, it is converted into a second charged particle. The second charged particle is another free source, which may be, for example, a low temperature plasma, and is mixed with the first charged particles to form a composite free source I.

In an embodiment of the invention, the first electrode portion 13 is a ground electrode, and the second electrode portion 14 is correspondingly a high voltage electrode for connecting an AC power generator 16 to form a high voltage electric field. The voltage applied by the first electrode portion 13 and the second electrode portion 14 may range, for example, from 2 kV to 5 kV, preferably 3.5 kV. In order to make the density of the composite free source I formed by the first charged particles and the second charged particles relatively uniform, the positions of the first electrode portion 13 and the second electrode portion 14 are preferably close to the electric spraying unit 11 The nozzle 111 does not exceed the nozzle 111, but is not limited thereto, and may be adjusted according to the condition of the first charged particle E1 and the second charged particle E2 in actual use.

Please refer to FIG. 2, which is a schematic diagram of the combination of the thermogravimetric analysis mass spectrometry system 1 of another embodiment of the present invention. The thermogravimetric mass spectrometry system 1 mainly comprises: an atmospheric free device 10 as described above; a thermogravimetric analysis device 20 for heating a test object A to form a neutral molecule A1; and a mass spectrometry device 30 having An ion inlet 301. In this embodiment, the composite free source I and the neutral molecule A1 are first subjected to ionic molecular reaction to form a charged molecule A2, and the charged molecule A2 subsequently enters the mass spectrometer 30 to analyze the mass-to-charge ratio of the charged molecule. The thermogravimetric analysis device 20 can include a heating unit 201, a weight measuring unit 202, and a gas output port 203 to obtain a temperature-to-weight curve of the object to be tested. The thermogravimetric analysis device 20 is, for example, a thermogravimetric analyzer having a function of programmable adjustment and setting of heating conditions. The mass spectrometer 30 can be, for example, an ion trap mass spectrometer.

In this embodiment, preferably, the composite free device 10 is disposed directly opposite the mass spectrometer 30, and the composite free source I and the ion inlet 301 of the mass spectrometer 30 Opposite each other. The gas output port 203 of the thermogravimetric analysis device 20 is disposed in the vicinity of the composite free source I, and is located between the composite free device 10 and the ion inlet 301 of the mass spectrometry device 30, so that the neutral molecule A1 can enter the The range of complex free source I reacts to form the charged molecule A2, which can be directed into the mass spectrometer by an electric field or vacuum.

The following exemplary illustrations illustrate the actual mode of operation of the thermogravimetric mass spectrometry system 1 of the present invention for analysis, but this mode of operation or description is not intended to limit the structure of the thermogravimetric mass spectrometry system 1.

In this analysis operation, the thermogravimetric analyzer used was a thermogravimetric analyzer manufactured by METTLER-TOLEDO, Switzerland, model TGA1. The mass spectrometer used was an ion trap mass spectrometer manufactured by Bruker Daltonics, Germany, model Esquire 6000.

First, take 1-10 mg of the solid sample to be analyzed and place it in the thermogravimetric analyzer. After closing the furnace body of the thermogravimetric analyzer, install the heating gas transmission line and the atmospheric free device. After the above device is set, the dynamic temperature rise condition (temperature vs. time) required by the program is set. During the analysis, the gas phase product generated by heating in the thermogravimetric analyzer is blown through the reaction gas, passes through the heating transmission line, and enters the free region between the composite free source generated by the atmospheric free device and the inlet of the mass spectrometer. The free reaction is carried out, and the generated ions are analyzed by electric field guidance and vacuum suction inside the mass spectrometer into the mass spectrometer. The composite free source is disposed about 1 cm from the entrance of the mass spectrometer directly opposite the mass spectrometer, and is perpendicular to the thermogravimetric analyzer by about 0.5 cm from the outlet of the heating transmission line. Therefore, the region surrounded by the composite free source, the thermogravimetric analyzer outlet, and the inlet of the mass spectrometer is the region where the free reaction proceeds.

Atmospheric free device and heat according to the present invention compared to conventional techniques The reanalysis mass spectrometry system can perform free reaction at normal temperature and pressure, and can generate two or more free sources at the same time. It is suitable for real-time analysis of a wide range of molecular species, can effectively detect target analytes, simplify mass spectrometry devices, and save Analyze time and cost.

The present invention has been disclosed in its preferred embodiments, and is not intended to limit the invention, and the present invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection is subject to the definition of the scope of the patent application.

10‧‧‧Atmospheric free device

11‧‧‧Electrical spray unit

12‧‧‧ gas chamber

13‧‧‧First electrode section

14‧‧‧Second electrode section

15‧‧‧DC power generator

16‧‧‧AC power generator

17‧‧‧Conducting components

111‧‧‧Nozzles

112‧‧‧ 容部

121‧‧‧ gas injection end

122‧‧‧export end

123‧‧‧ gas passage

131‧‧‧pipe body

132‧‧‧ openings

E1‧‧‧First charged particles

E2‧‧‧Second charged particles

I‧‧‧Complex free source

Claims (10)

An atmospheric free device, comprising: an electric spraying unit, comprising a nozzle and a receiving portion, wherein the receiving portion is provided with an electrospraying solution, and the electrospraying solution is applied by being away from the nozzle in the receiving portion a voltage, the electrospray solution is passed through the nozzle to generate a first charged particle; a gas chamber for accommodating and circulating a gas, comprising a gas injection end, an outlet end, and a gas passage, the electric spray a unit is disposed in the gas passage; a first electrode portion is disposed outside the electric spray unit; and a second electrode portion is disposed outside the gas chamber; wherein the first electrode portion and the second portion After the electrode portion is energized, an electric field is formed, the gas is converted into a second charged particle, and mixed with the first charged particle to form a composite free source. The atmospheric free device of claim 1, wherein the electric spraying unit is a capillary tube, and the nozzle is a nozzle of the capillary tube. The atmospheric free device of claim 1, wherein the electric spray unit is disposed coaxially with the gas passage. The atmospheric free device of claim 1, wherein the first electrode portion is a ground electrode, and the second electrode portion is a high voltage electrode. The atmospheric free device of claim 1, wherein the first electrode portion is a metal tube having a tube body and an opening portion, the electric spraying unit is disposed through the tube body, and the nozzle system is The opening is exposed. The atmospheric free device of claim 1, wherein the second zone The electro-particles are a low temperature plasma. A thermogravimetric mass spectrometry system comprising: the atmospheric free device according to claim 1; a thermogravimetric analysis device for heating a test object to form a neutral molecule; and a mass spectrometer Having an ion inlet; wherein the complex free source reacts with the neutral molecule to form a charged molecule, and the charged molecule then enters the mass spectrometer from the ion inlet to analyze the mass-to-charge ratio of the charged molecule. The thermogravimetric mass spectrometry system of claim 7, wherein the thermogravimetric analysis device comprises a heating unit, a weight measuring unit and a gas output port to obtain a temperature-to-weight change of the object to be tested. curve. The thermogravimetric mass spectrometry system of claim 8, wherein the gas outlet is disposed adjacent to the composite free source, and the neutral molecule enters the composite free source to react to form the charged molecule. The thermogravimetric mass spectrometry system of claim 7, wherein the composite free source of the composite free device and the ion inlet of the mass spectrometry device are opposite each other.