CN112067728A

CN112067728A - Rapid solid-phase extraction detection method for propofol in blood plasma

Info

Publication number: CN112067728A
Application number: CN202010760718.6A
Authority: CN
Inventors: 王海星; 林函
Original assignee: Second Affiliated Hospital and Yuying Childrens Hospital of Wenzhou Medical University
Current assignee: Second Affiliated Hospital and Yuying Childrens Hospital of Wenzhou Medical University
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2020-12-11
Anticipated expiration: 2040-07-31
Also published as: CN112067728B

Abstract

The invention discloses a rapid solid-phase extraction detection method for propofol concentration in blood plasma, which comprises the following steps: the C18 pipette tip contains C18 silica gel filler, and propofol-d is added into blood plasma to be detected₁₇Regulating the pH of the internal standard solution to obtain a plasma sample; performing solid phase extraction by using a C18 pipette tip to obtain a sample solution; centrifuging the sample solution, and performing subsequent liquid chromatography-mass spectrometry on the supernatant obtained by centrifuging; the peak area of the obtained propofol and propofol-d₁₇And taking the peak area ratio as x, and substituting the x into a corresponding curve equation to finally obtain the concentration of propofol in the blood plasma to be detected.

Description

Rapid solid-phase extraction detection method for propofol in blood plasma

Technical Field

The invention relates to a rapid solid-phase extraction detection method for propofol concentration in blood plasma.

Background

Propofol is widely used for induction and maintenance of anesthesia. Propofol is generally considered to be the most suitable intravenous anesthetic for short-term sedation due to its excellent performance in rapid induction and elimination, short duration of effect, mild post-anesthesia recovery, few side effects, and no teratogenic effects. In previous research reports, significant inter-individual differences of propofol anesthesia are caused and frequently reported by the influence factors such as the genotype of cytochrome P450 enzyme, the Body Mass Index (BMI) and age of patients and the pharmacokinetic parameters of propofol. In addition to medical use, addiction and death from propofol abuse is also very widespread worldwide. The use of propofol at too high or too low a dose can cause propofol infusion syndrome and intraoperative awareness, respectively, to occur, causing physiological and psychological harm to the patient. In conclusion, the detection of plasma propofol concentration is very important for pharmacokinetic and forensic toxicology studies.

Gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) are novel technologies with high specificity, sensitivity and accuracy, and are often applied to monitoring propofol plasma concentration. The plasma can be used for liquid chromatography-mass spectrometry combined analysis after sample pretreatment. Solid-phase extraction (SPE) selective adsorption extraction of non-polar target compounds in plasma matrices using C18 silica gel chromatography packing is a routine sample pretreatment method used for sample separation, concentration and purification purposes prior to mass spectrometry. However, the traditional solid phase extraction method needs to perform pretreatment processes such as protein precipitation or liquid-liquid extraction on a plasma sample, the whole operation is time-consuming and labor-consuming, the cost of related consumables is high, special instruments and equipment such as a solid phase extractor are needed, certain technical requirements are required for operators, and the wide application and research of the method in propofol analysis and detection are greatly limited.

In the traditional solid phase extraction method, if the pretreatment processes such as protein precipitation or liquid-liquid extraction and the like are not carried out on a plasma sample, the blockage of a solid phase extraction column is often caused, so that the subsequent operation of solid phase extraction cannot be finished.

Disclosure of Invention

The invention aims to provide a rapid solid-phase extraction detection method for propofol concentration in blood plasma, which is convenient to use.

In order to solve the technical problems, the invention provides a rapid solid-phase extraction detection method for propofol concentration in blood plasma, which comprises the following steps:

1) c18 pipette tip solid phase extraction:

the C18 pipette tip contains C18 silica gel filler, and comprises the following steps:

1.1), wetting and activating (fully wetting and activating) the C18 silica gel filler in the suction head by using a 50% acetonitrile aqueous solution, and balancing the C18 silica gel filler in the suction head by using a 1% formic acid aqueous solution to obtain a pretreated C18 pipette suction head;

1.2) adding 10 mu L of 50 mu g/mL propofol-d into 1mL of blood plasma to be tested₁₇Adjusting the pH of the internal standard solution to (4 +/-0.2) to obtain a plasma sample;

1.3), taking 100 mu L of plasma sample, and repeatedly sucking and discharging the plasma sample by using the pretreated C18 pipette tip obtained in the step 1.1);

1.4) firstly, flushing the C18 silica gel filler in the suction head after the step 1.3) with 0.1 percent formic acid aqueous solution;

then eluting the C18 silica gel filler in the suction head by using methanol as an elution solvent to obtain a sample solution;

1.5), centrifuging the sample solution at (8 +/-1) DEG C (10000 Xg for 5 minutes), and centrifuging the obtained supernatant (about 50 mu L) for subsequent liquid chromatography-mass spectrometry;

description of the drawings: the supernatant from the centrifugation was transferred to a sample vial and stored at-80 ℃ prior to liquid chromatography-mass spectrometry analysis.

2) Performing liquid chromatography-mass spectrometry;

3) the area of the propofol peak obtained in the step 2) and propofol-d₁₇The peak area ratio is taken as x, y is 0.0588x +0.0053, and y is the propofol concentration in μ g mL in the plasma to be tested^-1。

As an improvement of the rapid solid-phase extraction detection method for propofol in plasma of the present invention, in the step 2):

2.1) liquid chromatographic separation:

the sample introduction amount of the supernatant was 5. mu.L, and the column temperature was maintained at 30 ℃ during the analysis;

the elution solvent comprises elution solvent A and elution solvent B, wherein the elution solvent A is 0.1% formic acid water solution, the elution solvent B is acetonitrile, and the flow rate of linear gradient elution is set to be 0.4mL min^-1；

The chromatographic separation conditions were as follows:

0.0-0.5 min, 20-5% A;

0.5-2.0 min, 5% A;

2.0-2.1 min, 5-20% A;

2.1-4.0 min, 20% A;

2.2), mass spectrometry:

atmospheric Pressure Chemical Ionization (APCI) was used to analyze propofol and propofol-d₁₇The ion source of (1);

the parameters are set as follows: the ion source temperature is 150 ℃, the capillary voltage is-4.5 kV, the desolvation temperature is 500 ℃, the desolvation gas flow is 800L/h, and the taper hole gas flow is 50L/h; the triple quadrupole mass spectrometer was operated in the selective reaction monitoring SRM mode; m/z 177 → m/z 177 for propofol monitoring; m/z194 → m/z194 for propofol-d₁₇Monitoring; the respective cone voltages and collision energies of the two channels were set to 46V and 18V;

respectively obtaining the propofol peak area and propofol-d of the supernatant₁₇Peak area.

As a further improvement of the rapid solid-phase extraction detection method for propofol in plasma, the method comprises the following steps in step 2):

liquid chromatography was performed using a Waters ACQUITY H-class ultra high performance liquid chromatography system using a C18 reversed phase ultra high performance liquid chromatography column (HSST 31.8 μm, 100 mm. times.2.1 mm), and mass spectrometry was performed by combining a Woltz Xevo TQD triple quadrupole mass spectrometer (Woltz, UK) in negative ionization mode with the liquid chromatography system.

As a further improvement of the rapid solid-phase extraction detection method of propofol in blood plasma of the invention:

the number of times of repeatedly sucking and discharging in step 1.3) is 5-7.

in the step 2.1), the sample injection temperature is 8 ℃.

the C18 pipette tip is Agilent OMIX C18 pipette tip (10-100 μ L);

step 1.1): sucking 100 mu L of 50% acetonitrile aqueous solution and then discharging the waste liquid, and repeating the actions of sucking 50% acetonitrile aqueous solution and then discharging the waste liquid for 1-3 times (namely, operating for 2-4 times in total); thereby realizing full wetting and activating the C18 silica gel filler in the suction head;

subsequently, 100. mu.L of a 1% formic acid aqueous solution was aspirated and then the waste liquid was discharged, and then the operations of aspirating a 1% formic acid aqueous solution and discharging the waste liquid were repeated 1 to 3 times (i.e., 2 to 4 times in total), thereby achieving the equilibrium of the C18 silica gel packing in the pipette tip.

step 1.2): the pH value was adjusted with formic acid.

step 1.4): sucking 100 μ L of 0.1% formic acid aqueous solution, discharging the waste liquid, and repeating the above steps of sucking 0.1% formic acid aqueous solution and discharging the waste liquid 1-3 times (i.e., 2-4 times in total); thus realizing the washing of the C18 silica gel filler in the suction head after the step 1.3) is finished by 0.1 percent formic acid aqueous solution;

using 50 μ L of methanol as an elution solvent, sucking by a suction head and then discharging, repeating the suction head and then discharging for 1-3 times, and finally extracting the sample solution from the last discharge solution.

In the invention, a hand-held pipette is used, a glass fiber is used for supporting the pipette tip filled with a fixed volume or weight of nonpolar chromatographic separation materials such as C18 silica gel, and the whole C18 pipette tip solid-phase extraction process is completed by sucking and discharging different liquids. Firstly, sequentially using 50% acetonitrile aqueous solution and 1% formic acid aqueous solution to activate and balance chromatographic material packing such as C18 silica gel and the like; also includes preparing a plasma sample; secondly, non-polar propofol molecules in the plasma are selectively adsorbed and extracted by chromatographic packing such as C18 silica gel and the like, so that the extraction efficiency of propofol can be improved by repeated operation; thirdly, polar matrix molecules which are poorly adsorbed or not adsorbed in chromatographic packing such as C18 silica gel are washed away through the processes of sucking and discharging 0.1% formic acid aqueous solution; and fourthly, eluting propofol molecules adsorbed by chromatographic packing such as C18 silica gel and the like by using a methanol organic solvent for subsequent gas chromatography-mass spectrometry analysis or liquid chromatography-mass spectrometry analysis.

The invention utilizes the liquid-transfering suction head filled with a small amount of C18 silica gel chromatographic packing, does not need to carry out extra extraction processes such as protein precipitation and the like on a plasma sample, directly carries out solid-phase extraction on the plasma sample, separates and purifies nonpolar propofol drug molecules, and is used for gas chromatography-mass spectrometry analysis or liquid chromatography-mass spectrometry.

Compared with the traditional solid phase extraction method, the C18 liquid-transfer suction head solid phase extraction method omits the pretreatment process of plasma samples such as plasma protein precipitation and the like, has low material consumption cost, and can complete the whole solid phase extraction process only by using a common handheld liquid transfer device in a laboratory without additional instrument equipment (a solid phase extraction instrument). The chromatographic separation time of the invention is only 4 minutes, which is lower than the time (more than 5 minutes) required by the conventional chromatographic separation method, and the invention uses propofol-d with the chemical property closer to that of propofol₁₇As an internal standard, the accuracy and precision of the detection result can be improved.

In conclusion, the C18 liquid-transfering suction head solid phase extraction method has the advantages of low material cost, high speed, simple and easy operation, low technical difficulty, improved analysis and detection efficiency, wide application range and wide application range, and can be widely applied to the fields of clinical pharmacokinetics, forensic toxicology and the like.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

FIG. 1 is a schematic representation of a C18 pipette tip solid phase extraction;

in fig. 1, 1: c18 pipette tips; 2: a handheld pipettor; 3: plasma;

FIG. 2 shows propofol (A) and propofol-d₁₇(B) Chemical structure and secondary fragmentation mass spectra of (a).

FIG. 3 is a SRM monitoring profile for each plasma;

in the context of figure 3, it is shown,

(A)、blank human plasma; (B) 0.005 μ gm L^-1Human plasma standards of propofol; (C) 0.5. mu.g mL^-1Human plasma standards of propofol; (D) propofol anesthetized subject plasma;

the 3 plasma samples (B) to (D) contained 0.5. mu.g mL of the total amount except for (A)^-1Propofol-d₁₇An internal standard.

FIG. 4 is a standard curve for human plasma propofol concentration detection;

FIG. 5 is an experimental determination of the plasma propofol concentration of propofol target-controlled infusion anesthetized patients.

Detailed Description

The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto:

example 1:

solid phase extraction method of C18 liquid transfer suction head

The hand-held pipette was inserted into an agilent OMIX C18 pipette tip (10-100 μ L, millipore corporation, usa), and 100 μ L of 50% acetonitrile in water was first aspirated and the waste solution was then discharged, and then the above-described actions of 50% acetonitrile in water and then discharging the waste solution were repeated 2 times (i.e., three times in total) to sufficiently wet and activate the C18 silica gel filler in the tip. Subsequently, 100. mu.L of 1% formic acid aqueous solution was aspirated and then the waste liquid was discharged, and then the above-described operations of aspirating 1% formic acid aqueous solution and discharging the waste liquid were repeated 2 times (i.e., three times in total) to balance the C18 silica gel filler in the pipette tip.

To 1mL of the plasma to be tested, 10. mu.L of 50. mu.g/mL propofol-d was added₁₇Adding about 4 mu L of formic acid into the internal standard solution to adjust the pH value to 4 to obtain a plasma sample; 100 μ L of plasma sample was aspirated and discharged repeatedly (6 times in total) using the activated and equilibrated C18 pipette tip and the same centrifuge tube as a receiving vessel, to improve the efficiency of propofol extraction.

In order to wash the C18 silica gel pad adsorbing plasma propofol in the pipette tip, 100 μ L of 0.1% formic acid aqueous solution was aspirated, and then the waste liquid was discharged, and then the above-described actions of aspirating 0.1% formic acid aqueous solution and then discharging the waste liquid were repeated 2 times (total 3 times).

Finally, 50 μ L of methanol was used as an elution solvent, and the same centrifuge tube was used as a receiving container, and the sample solution was repeatedly aspirated and discharged (3 times in total), and the discharged solution of the last time in the centrifuge tube was the sample solution finally extracted.

The sample solution was centrifuged at 10000 Xg for 5 minutes at 8 ℃ and the resulting supernatant (about 50. mu.L) was transferred to a sample bottle and stored at-80 ℃ before liquid chromatography-mass spectrometry.

2. Chromatographic separation process

Liquid chromatography separation was performed by a Waters ACQUITY H-class ultra high performance liquid chromatography system using a C18 reverse phase ultra high performance liquid chromatography column (HSST 31.8 μm, 100 mm. times.2.1 mm), the column temperature being maintained at 30 ℃ during the analysis.

The elution solvent comprises elution solvent A and elution solvent B, wherein the elution solvent A is 0.1% formic acid water solution, the elution solvent B is acetonitrile, and the flow rate of linear gradient elution is set to be 0.4mL min^-1。

The final optimized chromatographic separation conditions were as follows:

0.0-0.5 min, 20-5% A;

0.5-2.0 min, 5% A;

2.0-2.1 min, 5-20% A;

2.1-4.0 min, 20% A.

The autosampler temperature was set to 8 ℃, the samples were temporarily stored as described above before analysis, and the sample amount of the sample solution was set to 5 μ L.

3. Mass spectrometry method

A volte Xevo TQD triple quadrupole mass spectrometer (volte, uk) in negative ionization mode was used in conjunction with a liquid phase system for mass spectrometry. Atmospheric Pressure Chemical Ionization (APCI) was used to analyze propofol and propofol-d₁₇The ion source of (1).

The specific instrument parameters are as follows: the ion source temperature is 150 ℃, the capillary voltage is-4.5 kV, the desolvation temperature is 500 ℃, the desolvation gas flow is 800L/h, and the taper hole gas flow is 50L/h. The triple quadrupole mass spectrometer was operated in the selective reaction monitoring SRM mode. Finish the productionPropofol and Propofol-d₁₇After secondary fragmentation mass spectrometry (fig. 2), two individual channels were finally determined: m/z 177 → m/z 177 for propofol monitoring; m/z194 → m/z194 for propofol-d₁₇And (5) monitoring. The respective cone voltages and collision energies for both channels were set at 46V and 18V.

Example 2 specificity verification of the method

To investigate the specificity of the propofol detection method, blank human plasma samples from 6 healthy subjects who had not used propofol within 72 hours were collected and processed directly (without propofol-d added) using the C18 pipette tip solid phase extraction method as described in step 1-step 3 of example 1₁₇Internal standard) and then subjected to liquid chromatography-mass spectrometry.

When the blank human plasma sample is detected, the area of the propofol peak is 0; propofol-d₁₇The peak area was 0.

That is, as shown in FIG. 3A, in the use for propofol and propofol-d₁₇Neither of the two selective responses monitored detected a significant effect of plasma matrix in the SRM channel.

Example 3 method sensitivity verification

Mixing propofol and fixed concentration of propofol-d₁₇After the internal standard solution is added into a blank human plasma sample, the propofol concentration prepared is 0.005 mu gm L^-1Human plasma standard (propofol-d)₁₇Internal standard concentration 0.5. mu.g mL^-1) Then, the sample treatment and the combined liquid chromatography-mass spectrometry analysis were performed by the methods described in step 1 to step 3 of example 1.

Propofol monitoring channel m/z 177 → m/z 177, propofol peak area of 6, signal-to-noise ratio of 10.

Propofol-d₁₇Monitor channel m/z194 → m/z194, propofol-d₁₇The peak area was 703.

As shown in FIG. 3B, the lower limit of quantitation LLOQ was determined to be 0.005. mu.g mL^-1。

Example 4 verification of linearity, accuracy and precision of the method

Different concentrations of propofol and fixed concentration are added(iii) propofol-d of degree₁₇After the internal standard solution is added into a blank human plasma sample, propofol concentrations of 0.005, 0.01, 0.5, 0.1, 0.5, 1.0, 2.0 and 5.0 mu g mL are prepared^-1Human plasma calibration standard (propofol-d)₁₇Internal standard concentration 0.5. mu.g mL^-1) Then, the sample treatment and the liquid chromatography-mass spectrometry analysis were performed by the methods described in step 1 to step 3 of example 1, and the linearity of the quantitative method was tested.

As shown in fig. 4, a calibration curve was constructed by a linear regression model using a weighted least squares regression method. The average linear regression equation for the calibration curve using 1/x as the weighting factor is expressed as y 0.0588x +0.0053, where y represents plasma propofol concentration and x represents propofol to propofol-d₁₇Peak area ratio of internal standard. Coefficient of linear correlation r²0.9992, the linearity of the method proved to be better. Propofol (0.5. mu.g mL) in human plasma standards^-1) And propofol-d 17 (0.5. mu.g mL)^-1) A representative selection response monitoring SRM profile of (a) is shown in fig. 3C.

The quantitative results of propofol monitoring channel m/z 177 → m/z 177 are: 0.4839 μ g m L^-1

I.e., 0.5. mu.g mL^-1At concentration, the propofol peak area is 5226; propofol-d₁₇The peak area was 642.

As shown in Table 1, the lowest quantitation limit of propofol (0.005. mu.g mL) was used^-1) And a low concentration (0.015. mu.g mL) was added^-1) Moderate (0.3. mu.g mL)^-1) High concentration (3.0. mu.g mL)^-1) Human plasma samples of propofol assessed the accuracy and precision of the method. Five replicates were performed in each evaluation. Finally, the within-batch accuracy was determined to be 90.0-108.6% and the between-batch accuracy was determined to be 93.3-113.3%. All these results meet the 85-115% range required for bioanalytical methods. Meanwhile, the precision in the batch and the precision between the batches are respectively determined to be 2.0-8.9 percent and 3.8-7.7 percent, and meet the standard of +/-15 percent. In addition to accuracy and precision, recovery and stability studies were also conducted on three quality control samples at different concentration levels, which were found to be in the 85-115% range required for bioanalytical methods.

TABLE 1 accuracy and precision results

Experiment 1,

In clinical practice, lower or higher concentrations of plasma propofol may lead to intraoperative consciousness or cardiopulmonary arrest, respectively. Therefore, the determination of plasma propofol concentration is very important in anesthesia. Approved by the local ethics committee and given informed consent was obtained. The plasma of a subject subjected to general propofol anesthesia is provided by a hospital, and the plasma propofol concentration is experimentally determined by the following experimental method:

1.c18 liquid-transfering suction head solid phase extraction method

Same as in step 1 of example 1.

2. Chromatographic separation process

Same as in step 2 of example 1.

3. Mass spectrometry method

Same as in step 3 of example 1.

Respectively obtaining the propofol peak area and propofol-d₁₇Peak area, calculation of propofol and propofol-d₁₇The peak area ratio of (a) is taken as x, and a calibration curve y is obtained by substituting 0.0588x +0.0053, wherein y is the propofol concentration of the plasma to be tested (the plasma of the subject).

The results obtained are shown in table 2 below.

TABLE 2

Comparing experiment 1, changing the elution solvent in experiment 1 from methanol to 80:20 water, v/v, keeping the volume consumption unchanged; and substituted into the calibration curve corresponding to the elution solvent, and the rest is identical to experiment 1.

Only the blood plasma a and the blood plasma F to be tested in table 2 were tested, and the results obtained were:

the propofol concentration of the plasma A to be tested is 1.88 mu gmL^-1The propofol concentration of the plasma F to be detected is 0.20 mu g mL^-1. The accuracy and recovery rate of the process are poor.

Comparing experiment 2, changing the '50% acetonitrile water solution' used for 'fully wetting and activating C18 silica gel filler in the suction head' in experiment 1 into 'methanol', and keeping the dosage unchanged; and the calibration curve is substituted into the calibration curve corresponding to the experimental condition, and the rest is equal to experiment 1.

the propofol concentration of the blood plasma A to be detected is 2.01 mu g mL^-1The propofol concentration of the plasma F to be detected is 0.26 mu g mL^-1. The accuracy and recovery rate of the process are poor.

Compared with experiment 3, the plasma sample adopted in experiment 1 is directly treated by a conventional solid phase extraction method, so that a solid phase extraction column is blocked, further subsequent experiment operation cannot be carried out, and an analysis and detection result of the propofol concentration cannot be obtained.

Finally, it is also noted that the above-mentioned lists merely illustrate a few specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.

Claims

1. The rapid solid-phase extraction detection method of propofol in blood plasma is characterized by comprising the following steps:

1) c18 pipette tip solid phase extraction:

1.1) wetting and activating a C18 silica gel filler in the suction head by using a 50% acetonitrile aqueous solution, and balancing the C18 silica gel filler in the suction head by using a 1% formic acid aqueous solution to obtain a pretreated C18 pipette suction head;

1.5) centrifuging the sample solution at the temperature of 8 +/-1 ℃, and carrying out subsequent liquid chromatography-mass spectrometry on the supernatant obtained by centrifuging;

2) performing liquid chromatography-mass spectrometry;

2. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 1, wherein in step 2):

2.1) liquid chromatographic separation:

The chromatographic separation conditions were as follows:

0.0-0.5 min, 20-5% A;

0.5-2.0 min, 5% A;

2.0-2.1 min, 5-20% A;

2.1-4.0 min, 20% A;

2.2), mass spectrometry:

atmospheric pressure chemical ionization was used to analyze propofol and propofol-d₁₇The ion source of (1);

the parameters are set as follows: the temperature of the ion source isThe capillary voltage is minus 4.5kV at 150 ℃, the desolvation temperature is 500 ℃, the desolvation gas flow is 800L/h, and the taper hole gas flow is 50L/h; the triple quadrupole mass spectrometer was operated in the selective reaction monitoring SRM mode; m/z 177 → m/z 177 for propofol monitoring; m/z194 → m/z194 for propofol-d₁₇Monitoring; the respective cone voltages and collision energies of the two channels were set to 46V and 18V;

3. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 2, wherein in step 2):

performing liquid chromatography separation by using a Waters ACQUITY H-class ultra high performance liquid chromatography system of a C18 reversed phase ultra high performance liquid chromatography column, and performing mass spectrometry by combining a Woltz Xevo TQD triple quadrupole mass spectrometer in a negative ionization mode with the liquid chromatography system.

4. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in any one of claims 1-3, wherein:

the number of times of repeatedly sucking and discharging in step 1.3) is 5-7.

5. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 4, wherein: in the step 2.1), the sample injection temperature is 8 ℃.

6. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 5, wherein:

the C18 pipette tip is an Agilent OMIX C18 pipette tip;

step 1.1): sucking 100 mu L of 50% acetonitrile water solution and then discharging the waste liquid, and repeating the actions of sucking 50% acetonitrile water solution and then discharging the waste liquid for 1-3 times; thereby realizing full wetting and activating the C18 silica gel filler in the suction head;

then, 100. mu.L of 1% formic acid aqueous solution was aspirated and then the waste liquid was discharged, and the operations of aspirating 1% formic acid aqueous solution and discharging the waste liquid were repeated 1 to 3 times to balance the C18 silica gel filler in the pipette tip.

7. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 6, wherein:

step 1.2): the pH value was adjusted with formic acid.

8. The method for rapid solid-phase extraction detection of propofol in plasma as claimed in claim 7, wherein:

step 1.4): sucking 100 mu L of 0.1% formic acid aqueous solution, discharging waste liquid, and repeating the actions of sucking 0.1% formic acid aqueous solution and discharging waste liquid for 1-3 times; thus realizing the washing of the C18 silica gel filler in the suction head after the step 1.3) is finished by 0.1 percent formic acid aqueous solution;