Mass spectrum online detection device based on double-beam pulse nanoliter electrospray ionization source

Abstract

The invention discloses a mass spectrum online detection device based on a double-beam pulse nanoliter electrospray ionization source, which comprises a double-spray assembly, a power supply, a first adjusting platform and two second adjusting platforms, and is characterized in that the first adjusting platform comprises a three-axis driving mechanism and a mounting table driven by the three-axis driving mechanism; the second adjusting platforms are symmetrically arranged on the mounting table, and each second adjusting platform is provided with a spraying assembly. The first adjusting platform is used for adjusting the second adjusting platform in the X direction, the Y direction and the Z direction, and coarse adjustment of the spraying assembly is achieved; the second adjusting platform can realize precise adjustment of each spraying assembly, so that the sample is fully ionized before entering the sample inlet of the mass spectrometer, the sample inlet speed of the ionized sample is increased, and the intensity and sensitivity of a mass spectrum signal are improved; due to high ionization efficiency and high sample injection efficiency, the loss of ions in the transmission process can be reduced, the stability and repeatability of a detection signal are improved, and the reliability and repeatability of an analyte analysis result are further ensured.

Description

Technical Field

[0001] The invention relates to the field of mass spectrometry online detection, and in particular to a mass spectrometry online detection device based on a dual-beam pulse nanoliter electrospray ionization source. Background Art

[0002] In recent years, mass spectrometry online detection technology has developed rapidly. With its simple operation, rapid analysis, and in-situ detection, this technology has shown broad development and application prospects. Traditional mass spectrometry online detection mainly focuses on analytes with high stability and high ionization efficiency, and it is difficult to achieve the mass spectrometry online detection needs of analytes with strong volatility, high reactivity, and low ionization efficiency. At present, the commonly used method is to improve the stability and ionization efficiency of these analytes through offline derivatization technology, but this method is complicated and time-consuming. In order to achieve online rapid detection of analytes with high volatility, high reactivity, and low ionization efficiency, and expand the application scope of mass spectrometry online detection technology, an analytical device that can overcome the above technical defects is urgently needed. To this end, existing manufacturers have shipped mass spectrometers with dual electrospray ionization sources (such as Waters' LockSpray dual electrospray ionization source), which use dual electrospray ionization sources to improve the ionization efficiency of samples. However, the spray position of the dual ion source cannot be adjusted, resulting in a relatively low injection efficiency, and it is impossible to achieve rapid injection of analytes with high volatility and high reactivity, and the mass spectrometry signal is affected due to low injection efficiency. It can be seen that how to improve the injection efficiency while improving the ionization efficiency of the mass spectrometer is one of the difficulties in expanding the application scope of mass spectrometry online detection. Summary of the invention

[0003] In view of this, the present invention proposes a mass spectrometry online detection device based on a dual-beam pulsed nanoliter electrospray ionization source, which can achieve high-precision adjustment of the spray position of the spray component and rapid injection of ion source samples, thereby expanding the detection objects of the mass spectrometry online detection device.

[0004] To achieve the above object, the present invention adopts the following technical solutions: The mass spectrometry online detection device based on a dual-beam pulse nanoliter electrospray ionization source described in the present invention includes a dual spray assembly and a power supply, wherein the induction electrodes of the spray assembly and the power supply are matched and connected one by one, and the power supply is a high-voltage pulse power supply; the online reaction detection device also includes a first adjustment platform and two second adjustment platforms, wherein the first adjustment platform includes a three-axis driving mechanism and a mounting platform driven by the three-axis driving mechanism; the second adjustment platform is symmetrically arranged on the mounting platform, and the second adjustment platform is an XYR three-axis displacement platform or an XYZR four-axis displacement platform; a spray assembly is arranged on each second adjustment platform, and the spray assembly also includes a through The sample loading module and the air intake module are connected by a three-way joint, the three-way joint has a first straight cylinder and a second straight cylinder vertically connected to the first straight cylinder, the sensing electrode is cylindrical and is installed at the first port of the first straight cylinder through a connecting joint; the sample loading module includes a sample injection pump and a nanoliter capillary spray needle connected by a sample injection pipeline, the nanoliter capillary spray needle is coaxially arranged in the first straight cylinder and the sensing electrode, the needle end of the nanoliter capillary spray needle passes through the sensing electrode, and one end of the nanoliter capillary spray needle is fixed at the second port of the first straight cylinder through a mounting piece; the air intake module is connected to the first straight cylinder and the sensing electrode through the second straight cylinder. The beneficial effect is that the present invention has two high-precision adjustable spray assemblies, which can realize modes such as symmetrical spray or cross spray, improve the mixing efficiency of samples and reagents, and promote the ionization of samples. The present invention utilizes the first adjustment platform to adjust the second adjustment platform in the X, Y and Z directions, thereby realizing the rough adjustment of the spray assembly; the second adjustment platform can realize the precise adjustment of each spray assembly, so that the sample is fully ionized before entering the injection port of the mass spectrometer, and the injection speed of the ionized sample can be increased, and the intensity and sensitivity of the mass spectrometry signal can be improved; due to the high ionization efficiency and high injection efficiency, the loss of ions in the transmission process can be reduced, the stability and repeatability of the detection signal can be increased, and the reliability and repeatability of the analyte analysis results can be further ensured.

[0005] Preferably, the air intake module comprises a mass flow meter and a gas heater connected in sequence through an air intake pipeline, and the air outlet of the air intake pipeline enters the first straight cylinder from the second straight cylinder. The air intake module allows sheath gas to enter the inner cavity of the sensing electrode through the first straight cylinder, and then ejects the electro-micro droplets. The high-temperature sheath gas can accelerate the volatilization of interfering reagents and matrix, thereby reducing the influence of matrix effect on the one hand and improving ionization efficiency on the other.

[0006] Preferably, the injection pump is a microinjection pump with a flow rate of 0.001 μL / min to 50 μL / min; the inner diameter of the nanoliter capillary needle is 0.1 μm to 10 μm, and the radial spacing between the inner wall of the sensing electrode and the nanoliter capillary needle is 50 μm to 1000 μm, so that the sheath gas wraps the sample and promotes the ionization of the sample.

[0007] Preferably, the output voltage of the high-voltage pulse power supply is ±5000V, the waveform is a square wave, the pulse frequency is 0 to 20 kHz, and the duty cycle is 1% to 100%. The present invention uses a high-voltage pulse power supply to form tiny charged spray droplets from the sample, thereby promoting the spray ionization of the sample.

[0008] In a preferred embodiment of the present invention, the second adjustment platform is an XYR three-axis displacement platform or an XYZR four-axis displacement platform, the XYR three-axis displacement platform has an adjustment accuracy of 10 μm in the X and Y directions, and its R-axis adjustment accuracy is 0.01°; the XYZR four-axis displacement platform has an adjustment accuracy of 10 μm in the X, Y and Z directions, and its R-axis adjustment accuracy is 0.01°. More preferably, the second adjustment platform uses a high-precision XYZR four-axis displacement platform. The present invention can first use the first adjustment platform to perform rough adjustments in the X, Y and Z directions, and then use the second adjustment platform to perform fine adjustments on the spray assembly in the X, Y, Z and R directions, thereby improving the accuracy of the spray assembly and further improving the mixing efficiency of the sample and reagent.

[0009] In a preferred embodiment of the present invention, the gas supply module supplies nitrogen into the sensing electrode, the flow rate of the nitrogen is 0.5-10 L / min, and the heating temperature is ≤250°C.

[0010] Preferably, the connecting joint is a Luer joint; the mounting piece is a sealing plug disposed in the second port of the first straight cylinder, and the nanoliter capillary needle is fixedly connected to the first straight cylinder via the sealing plug.

[0011] Compared with the prior art, the present invention has two high-precision adjustable spray components, which can realize symmetrical spray or cross spray and other modes, improve the mixing efficiency of samples and reagents, and promote the ionization of samples. The present invention uses the first adjustment platform to adjust the second adjustment platform in X, Y and Z directions, thereby realizing the rough adjustment of the spray component; the second adjustment platform can realize the precise adjustment of each spray component, so that the sample is fully ionized before entering the injection port of the mass spectrometer, and can increase the injection speed of the ionized sample, and improve the intensity and sensitivity of the mass spectrometry signal; due to the high ionization efficiency and high injection efficiency, the loss of ions in the transmission process can be reduced, the stability and repeatability of the detection signal can be increased, and the reliability and repeatability of the analyte analysis results can be further ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the present invention.

[0013] Figure 2 Schematic diagram of the spray assembly of the present invention.

[0014] Figure 3It is a schematic diagram of the interior of the spray assembly of the present invention (the air intake module is omitted). DETAILED DESCRIPTION

[0015] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0016] It should be noted that, in the description of the present invention, relational terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0017] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "connection" that may appear should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0018] like Figure 1 As shown, the mass spectrometry online detection device based on the dual-beam pulse nano-electrospray ionization source of the present invention comprises a dual-beam spray assembly 1 (for samples and reagents respectively) and a power supply 2. The sensing electrode 1.2 of each spray assembly 1 is connected to a power supply 2. The two power supplies 2 are preferably high-voltage pulse power supplies 2, with an output voltage of ±5000V, a square wave waveform, a pulse frequency of 0 to 20 kHz, and a duty cycle of 1% to 100%. The pulse amplitude, frequency, polarity and duty cycle of each power supply 2 can be flexibly set to achieve separate control of each beam of electrospray, and mass spectrometry detection of different analytes can be achieved by optimizing the ionization conditions, thereby expanding the application range of the mass spectrometer.

[0019] Combination Figure 1-3It can be seen that the online reaction detection device of the present invention also includes a first adjustment platform 3 and two second adjustment platforms 4. The first adjustment platform 3 includes a three-axis drive mechanism 3.1 (the Z direction adopts a scissor lifting structure with high stability) and a mounting platform 3.2 driven by the three-axis drive mechanism 3.1. The two second adjustment platforms 4 are symmetrically arranged on the mounting platform 3.2. Each second adjustment platform 4 is provided with a spray assembly 1. When working, the second adjustment platform 4 is adjusted in the three directions of X, Y, and Z by the first adjustment platform 3 to achieve coarse adjustment of the position of the spray assembly 1; the second adjustment platform 4 is preferably a high-precision XYZR four-axis displacement platform, and the adjustment accuracy of the X, Y and Z directions is 10μm, and the adjustment accuracy of the R axis is 0.01°, which can achieve high-precision adjustment in the X, Y, Z and rotation directions. In actual operation, the second adjustment platform 4 can be used to adjust the spatial position of each spray assembly 1, so that the spray end of the spray assembly 1 and the injection port 5 of the mass spectrometer are in the best position, ensuring that the ionized sample can enter the injection port 5 of the mass spectrometer unimpeded, thereby improving the injection efficiency, thereby reducing the loss of ions in the transmission process, and increasing the stability and repeatability of the detection signal; The spray assembly 1 includes a sample loading module and an air intake module connected by a three-way connector 1.1. The three-way connector 1.1 has a first straight cylinder 1.1a and a second straight cylinder 1.1b vertically connected to the first straight cylinder 1.1a (that is, the three-way connector 1.1 is a T-shaped connector). The sensing electrode 1.2 is cylindrical and is installed at the first port of the first straight cylinder 1.1a through a connecting connector 1.3 (preferably a Luer connector); the sample loading module includes a sample injection pump 1.4b connected by a sample injection pipeline 1.4a and a nanoliter capillary spray needle 1.4c, the nanoliter capillary spray needle 1.4c is coaxially arranged in the first straight cylinder 1.1a and the sensing electrode 1.2, the needle end of the nanoliter capillary spray needle 1.4c passes through the sensing electrode 1.2, and the fixed end of the nanoliter capillary spray needle 1.4c is fixed to the second port of the first straight cylinder 1.1a through a sealing plug; the injection pump 1.4b injects the sample or reagent into the nanoliter capillary spray needle 1.4c through the injection pipeline 1.4a, and forms ionized droplets at its spray end; The air inlet module is used to deliver sheath gas (nitrogen with a purity of ≥99.99% is preferred in the present invention) into the sensing electrode 1.2, which includes a mass flow meter 1.5b (for monitoring flow) and a gas heater 1.5c (for heating nitrogen, with a flow rate controlled at 0.5-10 L / min and a temperature preferably within 250°C) connected in sequence through an air inlet pipeline 1.5a. The air inlet of the air inlet pipeline 1.5a is connected to a nitrogen source (such as a nitrogen tank), and its air outlet extends to the first straight cylinder 1.1a through the second straight cylinder 1.1b. Since the second port of the first straight cylinder 1.1a is sealed by a sealing plug, the heated nitrogen enters the sensing electrode 1.2 through the first straight cylinder 1.1a and comes out through the spray end of the sensing electrode 1.2. The high-temperature nitrogen can accelerate the volatilization of interfering reagents and matrix, reduce the influence of the matrix effect, and improve the ionization efficiency.

[0020] The present invention has two high-precision adjustable spray components 1, one for sample spraying and the other for reagent spraying. In actual work, symmetrical spraying or cross spraying can be used to promote the mixing of samples and reagents and improve the ionization efficiency of samples. The first adjustment platform 3 adjusts the second adjustment platform 4 in X, Y and Z directions, thereby realizing the rough adjustment of the spray component 1. The second adjustment platform 4 can realize the precise adjustment of each spray component 1, so that the sample is fully ionized before entering the injection port 5 of the mass spectrometer, and can improve the injection speed of the ionized sample, and improve the intensity and sensitivity of the mass spectrometer signal. Due to the high ionization efficiency and high injection efficiency, the loss of ions in the transmission process can be reduced, the stability and repeatability of the detection signal can be increased, and the reliability and repeatability of the analyte analysis results can be further ensured.

[0021] In actual installation, the injection pump 1.4b is preferably a micro-injection pump with a flow rate of 0.001 μL / min to 50 μL / min, the inner diameter of the nanoliter capillary needle 1.4c is 0.1 μm to 10 μm, and the radial spacing between the inner wall of the sensing electrode 1.2 and the nanoliter capillary needle 1.4c is 50 μm to 1000 μm, providing a certain space for the sheath gas. When working, the sheath gas enters the sensing electrode 1.2 and heats the sample in the needle, thereby improving the ionization efficiency of the sample.

[0022] Finally, it should be emphasized that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Therefore, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A mass spectrometer online detection device based on a dual-beam pulse nanoliter electrospray ionization source, comprising a dual spray assembly and a power supply, wherein the sensing electrodes of the spray assembly and the power supply are connected one by one, characterized in that: The power supply is a high-voltage pulse power supply; the online reaction detection device also includes a first adjustment platform and two second adjustment platforms, the first adjustment platform includes a three-axis driving mechanism and a mounting platform driven by the three-axis driving mechanism; the second adjustment platform is symmetrically arranged on the mounting platform, and the second adjustment platform is an XYR three-axis displacement platform or an XYZR four-axis displacement platform; A spray assembly is arranged on each second adjustment platform, and the spray assembly also includes a sample loading module and an air intake module connected by a three-way joint, the three-way joint has a first straight cylinder and a second straight cylinder vertically connected to the first straight cylinder, the sensing electrode is cylindrical and is installed at the first port of the first straight cylinder through a connecting joint; the sample loading module includes a sample injection pump and a nanoliter capillary spray needle connected by a sample injection pipeline, the nanoliter capillary spray needle is coaxially arranged in the first straight cylinder and the sensing electrode, the needle end of the nanoliter capillary spray needle passes through the sensing electrode, and one end of the nanoliter capillary spray needle is fixed to the second port of the first straight cylinder through a mounting piece; the air intake module is connected to the first straight cylinder and the sensing electrode through the second straight cylinder.

2. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The air intake module comprises a mass flow meter and a gas heater which are sequentially connected via an air intake pipeline, and an air outlet of the air intake pipeline enters the first straight cylinder from the second straight cylinder.

3. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The injection pump is a microinjection pump with a flow rate of 0.001 μL / min to 50 μL / min; the inner diameter of the nanoliter capillary needle is 0.1 μm to 10 μm, and the radial spacing between the inner wall of the sensing electrode and the nanoliter capillary needle is 50 μm to 1000 μm.

4. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The output voltage of the high-voltage pulse power supply is ±5000V, the waveform is a square wave, the pulse frequency is 0-20kHz, and the duty cycle is 1%-100%.

5. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The adjustment accuracy of the X and Y directions of the XYR three-axis displacement platform is 10 μm, and the adjustment accuracy of the R axis is 0.01°; the adjustment accuracy of the X, Y and Z directions of the XYZR four-axis displacement platform is 10 μm, and the adjustment accuracy of the R axis is 0.01°.

6. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The gas supply module supplies nitrogen into the sensing electrode, the flow rate of the nitrogen is 0.5-10 L / min, and the heating temperature is ≤250°C.

7. The mass spectrometer online detection device based on a dual-beam pulse nano-electrospray ionization source according to claim 1, characterized in that: The connecting joint is a Luer joint; the mounting piece is a sealing plug arranged in the second port of the first straight cylinder, and the nanoliter capillary spray needle is fixedly connected to the first straight cylinder through the sealing plug.

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