GBC Inductively Coupled Plasma Time of Flight Mass Spectrometer (ICP-TOFMS)



1. Overview

*Inductively coupled plasma angular acceleration time-of-flight mass spectrometer (ICP-oa-TOF-MS) is used for qualitative, quantitative, and isotopic analysis of elements, with high sensitivity, high precision, and high accuracy for analyzing water-based solutions and laser ablation samples.

1.1 Instrument type

The instrument consists of an inductively coupled plasma ion source, ion optics, a right angle accelerated time-of-flight mass analyzer with an ion reflection cavity, and an ion detection system matched with a data processing system; The workstation and necessary workstation software are capable of instrument control, data acquisition, processing, and storage; The instrument should include all necessary sample introduction systems for maintaining high vacuum and traditional solution atomization, as well as relevant equipment and software necessary for the operation of the instrument.

1.2 Key indicator requirements

1.2.1 * Conduct quantitative analysis on no less than 60 elements simultaneously

1.2.2 Linear dynamic range of 108, with linear deviation kept within 20%

1.2.3 Fully automatic computer-controlled analysis process

1.2.4 Equipped with an interface that fully matches the laser ablation attachment to control the injection and analysis process of laser ablation

1.3 Main System Units of the Instrument

1.3.1 Computer controlled RF generator system, including RF power supply, impedance matching system, torch box, and atomizer components

1.3.2 Ion Sampling System and Ion Focusing Optical System

1.3.3 Vacuum system with readout and interlock system, with a gate valve behind the third stage cone to maintain the third stage cone without damaging the vacuum system

1.3.4 Computer controlled argon gas flow system

1.3.5 Right angle accelerating ion accelerator with ion reflection cavity

1.3.6 Threshold controlled pulse amplification cumulative ion detection system

1.3.7 Instrument control and data acquisition system implemented through computer

1.3.8 Desktop structured instruments

1.3.9 Optional software controlled automatic sampler

1.3.10 Concentric axis glass atomizer with constant temperature glass swirl chamber

1.3.11 Workstation System



2. Instrument operation performance indicators

2.1 Quality Scope

*The instrument should be able to detect all positive ions with a mass to charge ratio (m/z) within the range of 1-260 amu.

2.2 Instrument resolution capability

*The quality resolution capability (FWHM) of the quality analyzer should reach: for 5Li, m/Δ m>600; For 238U, m/Δ m>2000.

2.3 Linear dynamic range

The linear dynamic range of the instrument should reach 8 orders of magnitude, and the linear deviation should not exceed 20%.

2.4 Abundance sensitivity

Under normal operating conditions, the background value is less than 5cps (counts per second) within the full mass range of 1-260amu.

2.5 Oxide ions

Under normal operating conditions, the oxide signal strength of all elements is not greater than 3.0% of their ionic strength; The typical value of CeO/Ce is less than 1%.

2.6 High valence ions

Under normal operating conditions, the peak intensity of high valence ions for all elements is not greater than 2% of the peak intensity of their monovalent ions; The typical value of Ba++/Ba+is less than 1%.

2.7 Analysis speed

*The instrument must be able to complete the analysis of at least 120 elements within 30 seconds, which must include the sample channel flushing time for preparing for the next injection.



3. Instrument analysis performance indicators

3.1 Detection limit

Under normal operating conditions, using the manufacturer's default time window (or mass width window), the instrument should be able to obtain detection limits of<10ppt (ng/L) for Be, Co, Rh, In, Cs, U and<1 ppt (ng/L) for Rh, Cs, In, U in a 1% HNO3 aqueous solution containing 1 ppb (ng/mL). The detection limit adopts a 5-second integration time and 3 times the standard deviation of 10 readings.

3.2 Isotope ratio testing performance

*The measurement precision of Ag isotope ratio should be better than 0.1%. The test sample is a 10ug/L natural abundance Ag solution, and a 3x5s integration is used.



4. Technical specifications of RF generation system

4.1 A 27.12 MHz, 2.0KW RF power supply with continuously adjustable RF power within 1600W. There is a gas flow sensor equipped with an automatic cooling gas cut-off device at the outlet of the cooling gas.

4.2 In case of exceeding the operating limit, the safety or locking device will automatically cut off. The operating limits should include but are not limited to argon gas flow rate and cooling water flow rate.

4.3 Ignition, RF power control, impedance matching, and shutdown actions can be controlled manually and automatically.



5. Technical specifications of the injection system

5.1 Torch tube

*The torch tube is fixed on a movable bracket, which can move up and down, in and out, and side by side. The position of the torch tube relative to the sampling cone can be adjusted in the X, Y, and Z directions (with a stroke of 5-25 mm; -2-2 mm and -2-2 mm, respectively, with an adjustment step of 0.1 mm)

5.2 Nebulizer and Mist Chamber

5.2.1 The concentric axis atomizer is made of materials resistant to hydrochloric acid and nitric acid. The rate of solution entering the atomizer should be less than 800mL/min. The fog chamber is connected to the atomizer and is resistant to corrosion by hydrochloric acid and nitric acid. The fog chamber should be as small as possible to minimize memory effects. The atomizer and mist chamber both need to be cleaned and replaced.

5.2.2 * Three channels of argon gas (sample gas, plasma gas, and cooling gas) are equipped with adjustable electronic mass flow controllers, and each mass flow controller has a reading device to indicate the flow rate of each gas channel. The cooling gas flow sensor is installed on the argon outlet pipeline with an automatic shut-off device.

5.3 Peristaltic pump

The peristaltic pump should have a stable rate of transferring the solution to the atomizer, and the pump speed of the peristaltic pump should be continuously adjustable and controllable by a computer. The peristaltic pump should have at least 3 channels of pump heads.



6. Sampling and Time of Flight Analyzer

6.1 Sampling cone

The sampling cone is the first component at the interface between the plasma and the first stage vacuum. The material of the sampling cone must be corrosion-resistant under normal operating conditions, and its lifespan should not be less than 500 hours. The maintenance and replacement of the sampling cone can be carried out without damaging the high vacuum of the mass spectrometer. The acceptable content of undissolved solids in the solution should not be less than 0.3%.

6.2 Cut Cone

*The truncated cone defines the boundary between the first and second levels of vacuum and the second and third levels of vacuum. During normal analysis, the truncated cone should not be corroded, and maintenance and replacement of the truncated cone can be carried out without damaging the high vacuum of the mass spectrometer.

6.3 Ion Acceleration System

*Adopting a right angle acceleration method, the acceleration pulse frequency shall not be less than 30000 times per second.

6.4 Time of Flight Analyzer

6.4.1 The geometric structure of the time-of-flight analyzer consists of two 0.5m flight tubes with ion reflection chambers, and an ion whitening device is used to remove unwanted high-intensity ion flows.

6.4.2 When the normal operating limit is exceeded, the safety or locking device automatically cuts off the high voltage of the electrode. The operating limits should include but are not limited to vacuum errors, cooling gas errors, and water flow errors. Allow manual overload operation during initial tuning.



7. Specifications of vacuum chamber and pump

7.1 * The vacuum unit should include at least one mechanical pump and three turbo molecular pumps.

7.2 The vacuum unit should operate continuously and be able to extract multiple gases (including He) without the need for adjustment. This allows customers to use plasma gases other than argon according to their actual needs.



8. Performance indicators of instrument computer

8.1 Computer Functions

The computer should be able to control and monitor ICP-TOFMS instruments and their accessories, such as automatic sampler, laser ablation atomizer control, pre programming, and unmanned operation.

8.2 Data Collection

The computer system of ICP-TOFMS should be able to automatically collect mass spectrometry data within the range of 1-260 amu and calculate all major, trace, and trace elements in the sample to be tested. The detector mode should be optional for customers.

8.3 Automatic Analysis

In addition to initial start-up and tuning settings, unmanned analysis can also be performed, including controlling automatic samplers, laser ablation atomization sources, and ICP-TOFMS instruments. The integration time can be set arbitrarily within 5 minutes.

8.4 Software Package

8.4.1 The software package should include all necessary software for fully automated element and isotope ratio measurement, element concentration measurement, and system monitoring. The software should include a comprehensive monitoring program for ICP-TOFMS operations, including data acquisition and deletion, and should also be able to select subsequent tasks during automatic instrument operation.

8.4.2 Quantitative Calculation Basis for Elemental Concentration: The best match between the measured intensity and the standard curve, the experimental results of isotope dilution method, the experimental results of internal standard method, and the experimental results of standard addition method. Statistical information calculation of isotope and element concentrations and their ratios, measurement and calculation of ion beam stability and ion counting statistical data, as well as recording and reporting of analytical experimental conditions can be carried out.

8.4.3 The software should be able to automatically optimize all instrument parameters and perform semi quantitative analysis and traceable semi quantitative analysis.

*8.4.4 The software should also have mass spectrometry fingerprint function.



9. General instrument specifications

9.1 Voltage Requirements

220-240 VAC, 7kVA, 20A, 50-60 Hz.

9.2 Exhaust

Ventilation devices must be installed to exhaust exhaust gases and remove heat generated by plasma, electrical devices, and vacuum systems.