A puff-by-puff nicotine monitor and detection method for smoking tobacco products

Abstract

A puff-by-puff nicotine monitor and detection method for smoking tobacco products. The monitor comprises a puff control unit, a smoking device holder, a smoke capture unit, a detection unit, and a computer data analysis unit. Each unit is connected by a pipeline to form a closed detection system. The instrument and method can instantly obtain the nicotine content in the aerosol of each puff (i.e., the nicotine release per puff, μg·puff). ‑1 、Consumer nicotine exposure rate level μg•min ‑1 ), further data such as cumulative nicotine release, cumulative consumer nicotine exposure, and nicotine utilization efficiency can be obtained. A curve of puff-by-puff nicotine release in aerosol versus puff number can also be plotted, allowing for the assessment of nicotine release stability in smoking tobacco products. This enables in vitro, continuous, online, real-time, and on-site testing of nicotine content in smoking tobacco products, providing technical support and scientific basis for safety risk assessment, quality control, product design, and policy development for smoking tobacco products.

Description

Technical Field

[0001] The present invention relates to the technical field of puff-by-puff quantitative dynamic monitoring of nicotine content in smoking tobacco products, and in particular to a puff-by-puff nicotine monitoring device and detection method for smoking tobacco products, which can be used for in vitro, continuous, online, immediate, and on-site detection of nicotine content in smoking tobacco products. The detection indicators include the puff-by-puff nicotine content (μg·puff) in the fresh smoke aerosol generated during product use. -1 ), cumulative nicotine release (μg) and nicotine release degree (%). Background Art

[0002] Smoking tobacco products include cigarettes, heated cigarettes, electronic cigarettes, etc.

[0003] Cigarettes are tobacco products made by rolling tobacco into strips using cigarette paper.

[0004] Heated tobacco products (HTP) are products that use an independent heat source (such as electricity, aerosol, charcoal, etc.) to heat but not ignite the tobacco matrix to produce nicotine-containing aerosol.

[0005] An electronic cigarette is a product that can be used to consume a nicotine-containing aerosol through a mouthpiece or other product components, such as a cartridge, a reservoir, or other devices that do not contain a cartridge or reservoir. The term electronic cigarette refers to a growing range of devices, including disposable and refillable products of varying designs. Electronic cigarettes are also known by other names such as vapes, vape pens, vaping products, mods, pod-mods, electronic nicotine delivery systems (ENDS), or alternative nicotine delivery devices.

[0006] Nicotine is the main alkaloid in tobacco. Currently, the conventional control index for tobacco products by domestic and foreign regulatory agencies is nicotine content (μg·g -1 However, nicotine content is a product indicator and does not truly reflect product performance. Therefore, with the development of modern society, the need to regulate tobacco product performance indicators is becoming increasingly prominent. The two are closely related, but their meanings are distinct. The latter data more accurately reflects consumers' nicotine exposure levels and should be given greater attention in tobacco product regulation.

[0007] As a product performance indicator of tobacco products, it essentially refers to the consumer's exposure level, namely the total exposure and exposure rate. However, it is unrealistic to monitor this data in vivo, so the research and development of in vitro monitoring technology is necessary.

[0008] In vitro monitoring of nicotine exposure levels involves puff-by-puff monitoring of the nicotine content of smokeable tobacco products, specifically the release amount and release rate. The release amount is the cumulative amount of nicotine released from the product over a period of time, equivalent to the total in vivo exposure, measured in micrograms or milligrams. The release rate refers to the rate at which nicotine is released from the product over a specific time period, equivalent to the in vivo exposure rate, i.e., the amount of nicotine in the aerosol per puff of smoke, measured in micrograms per puff. The release amount and release rate can effectively characterize the product characteristics of a product, are suitable for risk assessment studies of the product, and provide a data foundation and theoretical basis for the formulation of product quality supervision and control policies.

[0009] For tobacco product research and development companies, the concept of nicotine release is crucial for identifying optimal leaf formulations and processing techniques, and providing guidance for product design. Release refers to the percentage of cumulative nicotine release over a period of time relative to the product's total nicotine content, expressed in units of %. This reflects the relationship between nicotine content and nicotine exposure, or in other words, nicotine utilization efficiency.

[0010] In summary, the puff-by-puff monitoring of nicotine content in smoking tobacco products includes the following three data tests, depending on the needs, namely: nicotine puff-by-puff release (μg·puff) -1 ), cumulative nicotine release (μg) and nicotine release degree (%).

[0011] At present, the puff-by-puff monitoring method for nicotine in smoking tobacco products follows the traditional analytical method, namely: using a linear smoking machine / modified rotary smoking machine and a Cambridge filter to capture puff-by-puff smoke, after nicotine is enriched to a certain extent on the Cambridge filter, the Cambridge filter is removed and subjected to pre-treatment such as organic solvent extraction, and then qualitative and quantitative analysis is performed using large-scale instruments such as gas chromatography and gas chromatography-mass spectrometry to calculate the nicotine release per puff (μg·puff). -1 ), cumulative nicotine release (μg) and nicotine release degree (%).

[0012] Therefore, the sample smoke extraction and pretreatment processes of traditional analytical methods are complex and time-consuming. Furthermore, with e-cigarettes, each cartridge can produce hundreds or even 500 puffs, making puff-by-puff nicotine monitoring using traditional methods prohibitively labor-intensive or even impossible. Therefore, the development of an analytical method and dedicated equipment capable of instant, puff-by-puff quantification is crucial.

[0013] Since nicotine (structural formula see Figure 1 ) has a conjugated structure and a characteristic absorption peak at 259nm in the ultraviolet region. The ultraviolet full-wavelength absorption spectrum is completed instantaneously and the data is presented immediately. Therefore, it is considered to use ultraviolet technology for real-time quantitative monitoring of nicotine.

[0014]

[0015] Single-channel or multi-channel smoking machines consist of a power unit, suction mechanism, cigarette holder, and smoke capture device. During operation, the entire system is sealed. A cigarette is placed in the holder and the switch is activated. The piston rod in the cylinder drives the piston in a reciprocating motion, generating negative pressure for suction. The smoke generated by the suction is captured by the capture device and then used to measure nicotine content.

[0016] In summary, this invention combines a smoking machine with ultraviolet quantitative monitoring technology to innovatively design, develop, and manufacture automated equipment specifically for the quantitative, puff-by-puff monitoring of nicotine in smoked tobacco products. This innovative method provides a new, real-time, in-situ, puff-by-puff nicotine monitoring method. This method provides accurate data and excellent stability, making it environmentally friendly compared to traditional detection methods. The experimental workflow features in-situ, online, and real-time monitoring, making operation more user-friendly. Furthermore, the specialized equipment boasts a simple hardware design and low cost. Summary of the Invention

[0017] The purpose of the present invention is to address the shortcomings of the current traditional analytical methods for monitoring the nicotine content of smoking tobacco products on a puff-by-puff basis. From a new perspective, the present invention designs, develops and manufactures a dedicated automated device for monitoring nicotine in smoking tobacco products on a puff-by-puff basis. This creatively invents a new method for continuously and online measuring the nicotine content in the aerosol of smoking tobacco products on a puff-by-puff basis.

[0018] The object of the present invention is achieved through the following technical solutions:

[0019] A puff-by-puff nicotine monitor for smoking tobacco products, comprising a smoking control unit, a smoking device holder, a smoke capture unit, a detection unit, and a computer data analysis unit, wherein the units are connected by pipelines to form a closed detection system;

[0020] The main body of the suction control unit is composed of a stepper motor, a two-position three-way valve, and a syringe pump. The stepper motor drives the screw to push and pull the syringe pump to complete the suction and exhaust work, and cooperates with the three-way valve to realize the process switching of suction and exhaust.

[0021] The smoke capture unit is composed of a detection pool containing a capture liquid and a magnetic stirring device. The detection pool is placed on the magnetic stirring device, which can stir the liquid in the detection pool, mix it evenly, and eliminate bubbles.

[0022] The detection unit includes a deuterium lamp, a shutter, a focusing lens, a fiber optic spectrometer and a fiber optic probe, and the fiber optic probe is arranged below the liquid level of the capture liquid in the detection pool;

[0023] The detection pool is a closed structure and is respectively provided with an air extraction interface connected to the suction control unit, an aerosol interface connected to the smoking device holder, and an optical fiber probe insertion interface; the suction control unit allows the smoke to pass into the detection pool and the aerosol is captured by the capture liquid. The optical fiber probe set in the capture liquid transmits the measured ultraviolet light detection signal to the spectrometer in real time for ultraviolet full-wavelength absorption spectrum detection, which is then analyzed by the computer data analysis unit to obtain the detection result.

[0024] In the present invention, the detection pool can be a counter-radiation detection pool, and the pool body has a total of 4 openings, namely: a smoke aerosol passage interface A, an exhaust interface B above the capture liquid surface, and an optical fiber probe transmitting light passage plug-in interface C and a receiving light passage plug-in interface D; wherein, the A interface is connected to the clamping device mouthpiece by a capillary tube to introduce the aerosol into the capture liquid, and the position of the A port is not limited, as long as the aerosol can be completely introduced into the capture liquid without causing backflow; the B port is connected to the suction control unit for exhaust, and the position of the B port must be higher than the capture liquid surface; the C port and the D port are compared with each other and used as light passages to detect the capture liquid. The positions of the C and D ports can achieve that the transmitting light passage and the receiving light passage are both located below the liquid surface and the positions are compared (the existing optical fiber spectrometer can be correspondingly configured with transmitting and receiving split counter-radiation optical fibers).

[0025] Furthermore, the optical path between the transmitting light path and the receiving light path in the opposed-beam capture pool is adjustable, that is, the distance between the transmitting end and the receiving end is adjustable.

[0026] The detection cell can also be a single-chamber, radiative detection cell with three openings: a smoke aerosol passage port A, an air extraction port B located above the capture liquid level, and a fiber optic probe insertion port C. Ports A and C are both located on the upper end surface of the detection cell. The inner shape of the single-chamber, radiative detection cell can be, but is not limited to, a rectangular parallelepiped, a cylinder, or an inverted cone (such a shape can effectively reduce the volume of the capture liquid).

[0027] The detection pool can also be a radiation detection pool with a U-shaped cavity structure. The pool body has three openings, namely the smoke aerosol passage interface A located on the upper end face of one side cavity, the exhaust interface B located above the liquid surface of the captured liquid, and the optical fiber probe insertion interface C located on the upper end face of the other side cavity.

[0028] The smoking device holder is used to fix the smoking device, and the interface is adjustable so that it is suitable for cigarette holders of different shapes, such as oval, round, square, rectangular, and special shapes; its material is metal, polymer, glass, preferably PVC.

[0029] The inner cavity volume of the detection cell is a cell body that can hold 2-20 mL of solvent (preferably 4-20 mL); its material is metal, polymer, glass, or quartz material, and glass or polymer material is recommended; the overall shape of the detection cell is cylindrical, rectangular, or cube-shaped.

[0030] The capture liquid is pure water or artificial saliva that can dissolve nicotine. The formula of artificial saliva includes but is not limited to the following ingredients: deionized water, NaCl, KCl, Na2SO4, NH4Cl, CaCl2·2H2O, NaH2PO4·2H2O, CN2H4O, and NaF.

[0031] A method for detecting nicotine using the aforementioned puff-by-puff nicotine monitor implements continuous in-situ capture and quantitative detection of the nicotine content of puff-by-puff aerosols from smokable tobacco products (including cigarettes, heated cigarettes, and electronic cigarettes) through the monitor's automatic puffing, smoke capture, full-wavelength absorbance detection, and computer data analysis and automatic quantitative detection functions. The method specifically includes effectively capturing puff-by-puff smoke aerosols with a capture liquid to form a dynamic nicotine test solution E. Based on the characteristic ultraviolet absorption spectrum of nicotine's conjugated structure, a fiber optic spectrometer is used to rapidly acquire a full-wavelength absorption spectrum of E. The instantaneous nicotine concentration in E is then determined based on the relationship between nicotine absorbance and nicotine concentration, which conforms to the law of light absorption. Since the volume of the capture liquid is known, the nicotine content can be calculated. Furthermore, the dynamic nicotine concentration can be recorded at fixed time intervals, and a nicotine release behavior curve can be plotted with time as the horizontal axis and the puff amount, cumulative amount, or degree of nicotine release as the vertical axis.

[0032] The puffing parameters may use, but are not limited to, the puffing parameters of the following documents: GB 41700-2022 "Electronic Cigarettes"; GB / T 19609-2004 "Cigarettes - Determination of Total Particulate Matter and Tar Using a Conventional Analytical Smoking Machine"; ISO 4387 "Cigarettes - Determination of Total Particulate Matter and Nicotine-Free Dry Particulate Matter Using a Conventional Analytical Smoking Machine", etc.

[0033] The method of using the monitor of the present invention is:

[0034] A smokeable tobacco product sample is placed in the holder of the nicotine puff monitor. Puff parameters are set according to ISO or HCl puffing mode. A certain volume of air is drawn at regular intervals. The sample smoke is then drawn into the capture liquid in the detection cell, where it dissolves and forms a test solution of a certain concentration. The absorbance is then measured. Based on the linear relationship between nicotine concentration and nicotine absorbance, which conforms to the law of light absorption, the nicotine concentration in the system is determined. A curve of nicotine change with puff number is then plotted, representing the nicotine release behavior monitoring curve for smokeable tobacco products.

[0035] For detailed experimental procedures, see the specific implementation case.

[0036] The advantages of the present invention are:

[0037] 1. The experimental method described in the present invention is characterized by its practicality, novelty, and innovation. It selectively integrates smoking simulation technology, spectroscopy technology, analytical technology, computer technology, and fiber optic technology, and innovatively achieves in vitro, online, real-time, and continuous analysis of the nicotine content in the aerosol released from smoked tobacco products on a puff-by-puff basis.

[0038] 2. The assay method described in the present invention is characterized by accurate data, good reproducibility, high degree of automation, and ease of promotion. It can effectively simulate the puff-by-puff nicotine release behavior of smokeable tobacco products in vitro and is highly practical. It provides important technical support and scientific basis for product design, quality control, risk assessment, and policy formulation of smokeable tobacco products. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of the first structure of the monitor of the present invention (the detection cell is a beam-type),

[0040] Figure 2 Schematic diagram of the second structure of the monitor of the present invention (the detection cell is a radiation type U-shaped cavity structure),

[0041] Figure 3 Schematic diagram of the U-shaped cavity structure detection pool

[0042] Figure 4 This is a schematic diagram of the third structure of the monitor of the present invention (the detection cell is a single-cavity structure of the radiation type).

[0043] Figure 1-4 Among them, 1. Motor, 2. Syringe pump, 3. Suction channel, 4. Three-way valve, 5. Exhaust port, 6. Suction channel, 7. Smoking machine interface (i.e., suction interface), 8. Aerosol interface, 9. Retractable rigid optical fiber, 10. Optical fiber interface (i.e., optical fiber probe plug interface), 11. Optical fiber probe, 12. Detection cell, 13. Magnetic stirring device, 14. Deuterium lamp light source, 15. Motor shutter, 16. Focusing lens, 17. Optical fiber spectrometer, 18. Computer data analysis unit.

[0044] Figure 5 is a schematic diagram of the fiber optic probe structure.

[0045] Figure 5 Middle: 11-1 is the reflector head, 11-2 is the optical fiber holder, 11-3 is the optical fiber bundle, 11-4 is the incident lens, and 11-5 is the reflector.

[0046] Figure 1-5 middle, Indicates the reciprocating direction of the injection pump, → indicates the working direction of the three-way valve,

[0047] represents the flue gas path, represents the incident light, Indicates outgoing light and signals.

[0048] Figure 6 : 2# Nicotine cumulative release change diagram. DETAILED DESCRIPTION

[0049] The present invention is further described below with reference to the accompanying drawings (embodiments):

[0050] like Figure 1-4 As shown: The puff-by-puff nicotine monitor for smoking tobacco products of the present invention includes a smoking control unit, a smoking device holder, a smoke capture unit, a detection unit, and a computer data analysis unit. Each unit is connected by a pipeline to form a closed detection system;

[0051] The main body of the suction control unit is composed of a stepper motor 1, a two-position three-way valve 4, and a syringe pump 2. The stepper motor 1 drives the screw to push and pull the syringe pump 2 to complete the suction and exhaust work, and cooperates with the three-way valve 4 to realize the process switching of suction and exhaust;

[0052] The smoke capture unit is composed of a detection pool 12 containing a capture liquid and a magnetic stirring device 13. The detection pool 12 is placed on the magnetic stirring device 13, which can stir the liquid in the detection pool 12, mix it evenly, and eliminate bubbles.

[0053] The detection unit includes a deuterium lamp 14, a shutter 15, a focusing lens 16, a fiber optic spectrometer 17 and a fiber optic probe 11. The fiber optic probe 11 (including the incident optical fiber 9) is arranged below the liquid level of the capture liquid in the detection pool 12;

[0054] The detection cell is a closed structure and is respectively provided with an exhaust interface 7 connected to the suction control unit, an aerosol interface connected to the smoking device holder, and an optical fiber probe insertion interface 10; the suction control unit allows the smoke to pass into the detection cell 12, where the aerosol is captured by the capture liquid. The optical fiber probe 11 set in the capture liquid transmits the measured ultraviolet light detection signal in real time to the spectrometer 17 for ultraviolet full-wavelength absorption spectrum detection, which is then analyzed by the computer data analysis unit 18 to obtain the detection result.

[0055] In the present invention, the detection cell can be a beam detection cell (see Figure 1), the pool body has a total of 4 openings, namely: the smoke aerosol path interface A (i.e., position 8), the exhaust interface B above the capture liquid surface (i.e., position 7), and the optical fiber probe emission light path plug-in interface C and the receiving light path plug-in interface D (i.e., position 9); among them, the A interface is connected to the holder mouthpiece by a capillary tube to introduce the aerosol into the capture liquid. The position of the A port is not limited, as long as the aerosol can be completely introduced into the capture liquid without causing backflow; the B port is connected to the suction control unit for exhaust, and the position of the B port must be higher than the capture liquid surface; the C port and the D port are compared with each other and used as light paths to detect the capture liquid. The positions of the C and D ports can achieve that the emission light path and the receiving light path are both below the liquid surface and the positions are compared.

[0056] Furthermore, the optical path between the transmitting light path and the receiving light path in the counter-beam capture pool is adjustable, that is, the distance between the transmitting end and the receiving end is adjustable (a retractable hard counter-beam optical fiber 9 is used here), and the adjustable optical path can be divided into: both ends are adjustable, one end is fixed and the other end is adjustable.

[0057] The detection cell can also be a radiation detection cell, which is a single-chamber structure (see Figure 4 The cell body has three openings: smoke aerosol passage port A (position 8), air extraction port B (position 7) located above the capture liquid level, and fiber optic probe insertion port C (position 10). Ports A and C are both located on the upper end surface of the detection cell. The inner cell shape of the single-cavity, collective radiation detection cell can be, but is not limited to, a rectangular parallelepiped, a cylinder, or an inverted cone.

[0058] The detection cell can also be a radiation detection cell, which is a U-shaped cavity structure (see Figure 2 The cell has three openings: smoke aerosol port A (numbered 8) on the upper end of one side, air extraction port B (numbered 7) above the capture liquid level, and fiber optic probe port C (numbered 10) on the upper end of the other side. This U-shaped cell has the advantage of completely preventing air bubbles from interfering with absorbance.

[0059] The structure of the optical fiber probe used in the radiation detection cell is as follows: Figure 5 As shown, after inserting the detection pool 12, see Figure 2 、 Figure 4 .

[0060] The following is a further description of the detection operation process with reference to the accompanying drawings:

[0061] The method for monitoring nicotine release from a smoking tobacco product described in the present invention is an in vitro simulation test using a specially designed, developed, and self-made instrument. The specific implementation process is as follows (the order of some processes is adjustable):

[0062] 1) Open the nicotine puff-by-puff monitoring and quantitative instrument (see Figure 1 );

[0063] 2) Turn on the deuterium lamp and preheat it;

[0064] 3) Exhaust the medium solution;

[0065] 4) Install the detection pool 12. The volume of the medium solution can be adjusted according to the experimental requirements;

[0066] 5) Subtract blanks;

[0067] 6) Take one sample and place it on the smoking device interface 8 of the nicotine puff monitor, which is connected to the detection cell 12 via a pipe;

[0068] 7) Select smoking mode and start smoking;

[0069] 8) Fresh flue gas is sucked into the medium solution and dissolved by magnetic stirring to form a stable system of the test solution. Stirring is stopped when the bubbles disappear;

[0070] 9) Under the control of the computer program on the time node, the UV spectrum automatically starts and performs full wavelength scanning with a scanning range of 180nm-600nm.

[0071] 10) If the nicotine content of a single puff of the sample aerosol is too high and exceeds the maximum absorbance limit, the distance of the retractable rigid optical fiber 9 can be adjusted to shorten the optical path to a minimum of 0.5 mm.

[0072] 11) Based on the full-wavelength absorbance values of ultraviolet absorption measured by the above process and the linear relationship between nicotine concentration and nicotine absorbance, the nicotine concentration in the medium solution is automatically calculated based on the powerful computing power of the computer 18. The concentration is multiplied by the volume of the medium to obtain the nicotine content of the aerosol per puff, that is, m = c * V. This data is the nicotine release per puff (m n );

[0073] 12) The dedicated equipment automatically repeats steps 7-11 according to the program settings and records data at a fixed time interval. Similarly, based on the powerful computing power of the computer 18, the cumulative amount of nicotine released (∑m) and the degree of nicotine release (% = (m1+m2+m3+…+m n ) / m 总 )

[0074] 13) Furthermore, a nicotine release behavior curve can be drawn; this curve can be used to examine product stability.

[0075] 14) Furthermore, the experimental process can be adjusted and applied to different experimental purposes.

[0076] Specific tests and implementation results

[0077] The following examples are intended to illustrate the present invention but are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the present invention, those skilled in the art may make various changes and modifications to the present invention, and these equivalents also fall within the scope of the appended claims of the application.

[0078] Example 1

[0079] Sample: Homemade electronic cigarette, sample number 1#.

[0080] Experimental purpose: To investigate the puff-by-puff nicotine release uniformity of this sample.

[0081] Experimental steps:

[0082] 1. Open the monitor of the present invention (see Figure 1 ), turn on the deuterium lamp, preheat it, use ultrapure water as the detection medium, exhaust it and inject it into the detection cell to a fixed volume of 7mL.

[0083] 2. Scan blank.

[0084] 3. Take one electronic cigarette sample numbered 1# and connect it to the smoke inlet pipe of the monitor.

[0085] 4. Select experimental parameters such as puff mode and number of puffs, and enter sample information (including but not limited to sample number, brand, model, total nicotine content, etc.), experimental purpose, file name, and other experimental information.

[0086] 5. Click Start on the computer to start the experimental program.

[0087] 6. After the experiment begins, the instrument begins to automatically detect and time each mouthful.

[0088] 7. After the set program is completed, the experiment will automatically stop and the file will be saved.

[0089] Experimental results: The results of the double-parallel experiments are shown in Table 1.

[0090] Experimental conclusion: Based on the data in Table 1, it can be concluded that the nicotine release of this sample is uniform on a puff-by-puff basis, and the release from the 1st to the 120th puff in the double parallel tests is relatively stable.

[0091] Example 2

[0092] Sample: A heated cigarette produced by a Chinese tobacco company, sample number 2#.

[0093] Experimental purpose: To investigate the puff-by-puff nicotine release stability of a new product.

[0094] Experimental steps:

[0095] 8. Turn on the dedicated equipment, turn on the deuterium lamp, preheat, use ultrapure water as the detection medium, exhaust and inject it into the detection cell, and adjust the volume to 4mL. (See Figure 4 structure)

[0096] 9. Scan blank.

[0097] 10. Take one heated cigarette sample numbered 2# and connect it to the smoke inlet pipe of the special equipment.

[0098] 11. Select experimental parameters such as puff mode and number of puffs, and enter sample information (including but not limited to sample number, brand, model, total nicotine content, etc.), experimental purpose, file name, and other experimental information.

[0099] 12. Click Start on the computer to start the experimental program.

[0100] 13. After the experiment begins, the instrument begins to automatically detect and time each mouthful.

[0101] 14. After the set program is completed, the experiment will automatically stop and the file will be saved.

[0102] Experimental results: See Table 2 for detailed data.

[0103] During the same period, a traditional method, namely smoking machine + gas chromatography / mass spectrometry, was used for method comparison. The experimental results are shown in Table 2. The changes in the cumulative release of nicotine over time are shown in Table 2. Figure 6 .

[0104] Table 1 Puff-by-puff nicotine monitoring data for sample 1# (n=2)

[0105]

[0106]

[0107] Table 2: Monitoring data of sample 2# using two methods

[0108]

[0109] The comparison of the implementation process of the two methods is shown in Table 3.

[0110] Table 3: Comparison of the implementation process of the two methods

[0111]

Claims

1. A puff-by-puff nicotine monitor for smoking tobacco products, characterized by: The device includes a puff control unit, a smoking device holder, a smoke capture unit, a detection unit, and a computer data analysis unit. Each unit is connected by pipes to form a closed detection system. The nicotine monitor can be used for in vitro, continuous, online, immediate, and on-site detection of nicotine release from smoking tobacco products. The detection indicators include the puff-by-puff nicotine content in the fresh smoke aerosol generated during product use (μg·puff). -1 , cumulative nicotine release μg and nicotine release degree; The suction control unit is composed of a stepper motor, a two-position three-way valve, and a syringe pump. The stepper motor drives the screw to push and pull the syringe pump to complete the suction and exhaust work, and cooperates with the three-way valve to realize the process switching of suction and exhaust. The smoke capture unit is composed of a detection tank containing a capture liquid and a magnetic stirring device, and the detection tank is placed on the magnetic stirring device; The detection unit includes a deuterium lamp, a shutter, a focusing lens, a fiber optic spectrometer and a fiber optic probe, and the fiber optic probe is arranged below the liquid level of the capture liquid in the detection pool; The detection cell is a closed structure and is respectively provided with an air extraction interface connected to a puff control unit, an aerosol interface connected to a smoking device holder, and an optical fiber probe insertion interface. The puff control unit allows smoke aerosol to pass into the detection cell, where it is captured by a capture liquid. The optical fiber probe, disposed in the capture liquid, transmits the measured ultraviolet light detection signal in real time to a spectrometer for ultraviolet full-wavelength absorption spectrum detection. The signal is then analyzed by a computer data analysis unit to obtain the detection result. This monitor selectively integrates smoking simulation technology, spectroscopy technology, analytical technology, computer technology and fiber optic technology, and innovatively realizes in vitro, online, real-time and continuous analysis of nicotine content in aerosol released from smoking tobacco products on a puff-by-puff basis. The detection cell may be a beam-type detection cell, with a total of four openings on the cell body, namely: a smoke aerosol passage interface A, an exhaust interface B above the capture liquid surface, and an optical fiber probe transmission light passage interface C and a receiving light passage interface D; wherein, the A interface is connected to the holder mouthpiece by a capillary tube to introduce the aerosol into the capture liquid, and the position of the A port is not limited, as long as the aerosol can be completely introduced into the capture liquid without causing backflow; the B port is connected to the suction control unit for exhaust, and the position of the B port must be higher than the capture liquid surface; the C port and the D port are mutually contrasted and used as optical paths to detect the capture liquid, and the positions of the C and D ports can ensure that the emission light path and the receiving light path are both below the liquid surface and in contrast; The detection pool may be a collective radiation detection pool. When the collective radiation detection pool is a single-cavity structure, the pool body has three openings, namely, the smoke aerosol passage interface A, the exhaust interface B located above the liquid surface of the captured liquid, and the optical fiber probe interface C. Ports A and C are both located on the upper end face of the detection pool; when the collective radiation detection pool is a U-shaped cavity structure, the pool body has three openings, namely, the smoke aerosol passage interface A located on the upper end face of one side cavity, the exhaust interface B located above the liquid surface of the captured liquid, and the optical fiber probe interface C located on the upper end face of the other side cavity.

2. The puff-by-puff nicotine monitor for smoking tobacco products according to claim 1, characterized in that: The optical path between the emitting light path and the receiving light path in the opposed-beam collecting pool is adjustable, that is, the distance between the emitting end and the receiving end is adjustable.

3. The puff-by-puff nicotine monitor for smoking tobacco products according to claim 1, characterized in that: The smoking device holder is used to fix the smoking device, and the interface is adjustable so that it is suitable for cigarette holders of different shapes, such as oval, round, square, rectangular or special shapes; and the material thereof is metal, polymer or glass.

4. The puff-by-puff nicotine monitor for smoking tobacco products according to claim 1, characterized in that: The inner cavity volume of the detection cell is a cell body that can hold 2-20 mL of solvent; its material is metal, polymer, glass or quartz material; the overall shape of the detection cell is cylindrical, rectangular or cube-shaped.

5. The puff-by-puff nicotine monitor for smoking tobacco products according to claim 1, characterized in that: The capture liquid is pure water or artificial saliva that can dissolve nicotine.

6. A method for detecting nicotine using the puff-by-puff nicotine monitor according to claim 1, characterized in that: The monitor's automatic puffing, smoke capture, full-wavelength absorbance detection, and computer data analysis and automatic quantitative detection functions enable continuous in-situ capture and quantitative detection of the nicotine content of each puff of aerosol from a smokeable tobacco product. Specifically, the monitor uses a capture liquid to effectively capture each puff of smoke aerosol to form a dynamic nicotine test solution E. Based on the characteristic ultraviolet absorption spectrum of the conjugated structure of nicotine, a fiber optic spectrometer is used to quickly obtain a full-wavelength absorption spectrum of E. Based on the relationship between nicotine absorbance and nicotine concentration, which conforms to the law of light absorption, the instantaneous nicotine concentration in E is obtained. Since the volume of the capture liquid is known, the nicotine content can be calculated. Furthermore, the dynamic nicotine concentration can be recorded at fixed time intervals, and a nicotine release behavior curve can be plotted with time as the horizontal axis and the puff-by-puff or cumulative amount of nicotine or the percentage of nicotine released as the vertical axis.

7. The method for detecting nicotine according to claim 6, wherein: The smoking tobacco product is a cigarette, a heated cigarette or an electronic cigarette.

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