Method for detecting fluorine content in medicine based on X-ray fluorescence spectrometry

Abstract

The invention relates to the technical field of analytical chemistry, in particular to a method for detecting fluorine content in medicine based on X-ray fluorescence spectrometry, which comprises the following steps: performing ultrasonic treatment on graphene oxide to uniformly disperse the graphene oxide to obtain graphene oxide dispersion liquid; adding the graphene oxide dispersion liquid into the aqueous solution of the fluorine-containing medicine, uniformly stirring, and filtering the stirred solution by using an ultrafiltration membrane to form a uniform and compact thin film; and detecting the content of the fluorine element in the film by using a wavelength dispersion X-ray fluorescence spectrometer to obtain the concentration of the fluorine-containing medicine. According to the present invention, the graphene adsorption enrichment and X-ray fluorescence technology are adopted, and the flocculant is adopted to effectively improve the film forming speed, such that the fluorine-containing drug can be accurately detected, and the detection sensitivity and the detection accuracy can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of analytical chemistry, and in particular to a method for detecting fluorine content in medicine based on X-ray fluorescence spectroscopy. Background Art

[0002] Fluorine is an essential nutrient for the human body, and is particularly important for the growth, development and calcification of teeth and bones. However, the dose of fluorine that causes chronic poisoning in the human body is similar to the effective dose. Therefore, it is of great significance to detect the fluorine content in drugs. In the prior art, conventional methods for measuring the fluorine content in fluorine-containing drugs include the following:

[0003] Ion selective electrode method (ISE): Based on the electrochemical properties of the fluoride ion selective electrode, the fluoride content is quantified by measuring the electrode potential. This method is simple to operate and suitable for on-site detection, but it has low sensitivity and is sensitive to interfering ions in the sample. Ion chromatography (IC): Fluoride ions are separated by ion exchange columns and quantitatively analyzed in combination with conductivity detectors. This method has high sensitivity and good selectivity, but requires complex pretreatment steps and expensive instruments and equipment. Ultraviolet-visible spectrophotometry (UV-Vis): Fluorine reacts with specific color developers to form colored complexes, and the absorbance is measured by a spectrophotometer for quantification. This method is simple and low-cost, but has low sensitivity and selectivity. Mass spectrometry (MS): Including gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS), the sample is qualitatively and quantitatively analyzed by a mass spectrometer. Mass spectrometry has extremely high sensitivity and selectivity, but the instrument is expensive, the operation is complicated, and professional technicians are required.

[0004] X-ray fluorescence spectrometry (XRF) is a non-destructive testing technology that uses X-rays to excite elements in the sample, causing them to emit characteristic fluorescence, and qualitatively and quantitatively analyzes the energy and intensity of these fluorescences to determine the content of the elements. The pretreatment method of XRF has an important impact on the accuracy and sensitivity of sample analysis. The thin film method is one of the commonly used pretreatment methods. The thin film method has certain advantages in XRF quantitative analysis, especially in terms of simple sample preparation, small sample amount, and reduced matrix effect. However, the loading capacity of traditional support membranes such as ordinary filter paper and non-woven fabrics is limited, and the light scattering caused by the roughness of the surface has a greater impact on the signal-to-noise ratio, especially for low molecular weight elements. The fluorescence effect is more prominent. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a rapid, efficient and low-cost method for detecting the fluorine content in drugs based on X-ray fluorescence spectroscopy.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0007] A method for detecting fluorine content in a drug based on X-ray fluorescence spectroscopy is provided, which comprises the following steps:

[0008] The graphene oxide is ultrasonically treated to make it uniformly dispersed to obtain a graphene oxide dispersion; the graphene oxide dispersion is added to an aqueous solution of a fluorine-containing drug and stirred evenly, and the stirred solution is filtered using an ultrafiltration membrane to form a uniform and dense film; the content of fluorine element in the film is detected using a wavelength dispersive X-ray fluorescence spectrometer to obtain the concentration of the fluorine-containing drug.

[0009] Furthermore, the graphene oxide dispersion is added to the aqueous solution of the fluorine-containing drug, and an ion flocculant is added to the solution.

[0010] Furthermore, the ionic flocculant includes aluminum nitrate and calcium chloride.

[0011] The beneficial effects of the present invention are:

[0012] 1. Rapid detection: This method is simple to operate, the entire detection process is short, and it is suitable for efficient analysis.

[0013] 2. High sensitivity: X-ray fluorescence technology can achieve high-sensitivity detection of fluorine elements, with the minimum detection limit reaching 5ppm.

[0014] 3. High linearity: The correlation coefficient of the standard curve is high (0.96 when using aluminum nitrate and 0.99 when using calcium chloride), indicating the accuracy and reliability of the test results.

[0015] 4. Low cost: The preparation and use costs of graphene oxide are low, and flocculants such as aluminum nitrate and calcium chloride are also relatively cheap, making them suitable for large-scale applications.

[0016] 5. Low sample requirement: Due to the shallow penetration depth of X-ray fluorescence of fluorine, the effective measurement of sample requirements is limited to the surface part, and a large amount of sample is not required. By enriching low-concentration fluorine-containing drugs in a thin layer, the detection sensitivity can be further improved.

[0017] 6. Wide application: This method is not only suitable for drug testing, but can also be used in many fields such as environmental monitoring to achieve rapid quantitative analysis of fluorine-containing substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The standard curve obtained in Example 1;

[0019] Figure 2 This is the standard curve obtained in Example 2. DETAILED DESCRIPTION

[0020] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0021] Example 1

[0022] Take 0.1g of graphene oxide (GO), disperse it in 100mL of water, and ultrasonically treat it to make it uniformly dispersed to obtain an aqueous solution of 1mg / mL GO. Prepare an aqueous solution containing 10mg / mL 5-fluorouracil. Add the above GO dispersion to the aqueous solution containing 5-fluorouracil in different proportions, stir evenly, make GO and 5-fluorouracil fully contact, and use the high surface area and rich functional groups of GO to adsorb 5-fluorouracil. Preferably, an ionic flocculant can be added to the solution to further promote the combination of 5-fluorouracil and GO and improve the enrichment efficiency. Stirring allows the flocculant to fully play its role and form a GO complex containing 5-fluorouracil. The stirred solution is filtered using an ultrafiltration membrane, and the complex containing 5-fluorouracil and GO forms a uniform and dense film on the surface of the ultrafiltration membrane. The prepared film is dried at 60°C for 2h.

[0023] Place the dried GO film sample in the sample cup of the XRF instrument. Use wavelength dispersive X-ray fluorescence spectrometer to detect the content of F element, and record the X-ray count rate corresponding to the GO film made of different concentrations of 5-fluorouracil. Draw a standard curve and calculate the linear coefficient and sensitivity. Repeat the same operation with a 5-fluorouracil solution with a fluorine content equivalent to 100 mg / L, and the concentration of fluorine-containing drugs in the sample is 86 mg / L.

[0024] In this example, 0.2 M aluminum nitrate was used as a flocculant and added to a 1 mg / mL GO dispersion to promote the adsorption and enrichment of 5-fluorouracil. A GO composite film containing 5-fluorouracil was prepared through the above steps, and the content of F element was detected on a wavelength dispersive X-ray fluorescence spectrometer.

[0025] The experimental results are as follows Figure 1 As shown in the figure, the correlation coefficient of the obtained standard curve is 0.96, indicating that the method has good linearity. The quantitative limit of fluorine element is 5ppm, which shows the high sensitivity and accuracy of the method in the low concentration range. This method is not only simple and fast, but also low-cost, and is suitable for the rapid detection of fluorine-containing drugs.

[0026] Example 2

[0027] Take 0.1g of graphene oxide (GO), disperse it in 100mL of water, and ultrasonically treat it to make it uniformly dispersed to obtain an aqueous solution of 1mg / mL GO. Prepare an aqueous solution containing 10mg / mL 5-fluorouracil. Add the above GO dispersion to the aqueous solution containing 5-fluorouracil in different proportions, stir evenly, make GO and 5-fluorouracil fully contact, and use the high surface area and rich functional groups of GO to adsorb 5-fluorouracil. Preferably, an ionic flocculant can be added to the solution to further promote the combination of 5-fluorouracil and GO and improve the enrichment efficiency. Stirring allows the flocculant to fully play its role and form a GO complex containing 5-fluorouracil. The stirred solution is filtered using an ultrafiltration membrane, and the complex containing 5-fluorouracil and GO forms a uniform and dense film on the surface of the ultrafiltration membrane. The prepared film is dried at 60°C for 2h.

[0028] Place the dried GO film sample in the sample cup of the XRF instrument. Use a wavelength dispersive X-ray fluorescence spectrometer to detect the F content and record the X-ray count rate corresponding to the GO film made of 5-fluorouracil with different concentrations. Draw a standard curve and calculate the linear coefficient and sensitivity. Repeat the same operation with a 5-fluorouracil solution with a fluorine content equivalent to 100 mg / L, and the concentration of the fluorine-containing drug in the sample is 91 mg / L.

[0029] In this example, 0.2M calcium chloride was used as a flocculant and added to the GO dispersion to promote the adsorption and enrichment of 5-fluorouracil. A GO composite film containing 5-fluorouracil was prepared by the same steps, and the content of F element was detected on a wavelength dispersive X-ray fluorescence spectrometer.

[0030] The experimental results are as follows Figure 2 As shown in the figure, the correlation coefficient of the obtained standard curve is 0.99, indicating that the linearity of the method is very good. The limit of quantification of fluorine is 5ppm, which once again demonstrates the high sensitivity and accuracy of the method in the low concentration range. Compared with the use of aluminum nitrate, calcium chloride as a flocculant shows better effect in improving the linearity and detection stability of the method.

[0031] These two implementation cases demonstrate the effectiveness and reliability of the method of the present invention in detecting fluorine-containing drugs, and can meet the detection requirements under different experimental conditions.

[0032] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0033] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for detecting fluorine content in a drug based on X-ray fluorescence spectroscopy, characterized in that: The following steps are involved: The graphene oxide is ultrasonically treated to make it uniformly dispersed to obtain a graphene oxide dispersion; the graphene oxide dispersion is added to an aqueous solution of a fluorine-containing drug and stirred evenly, and the stirred solution is filtered using an ultrafiltration membrane to form a uniform and dense film; the content of fluorine element in the film is detected using a wavelength dispersive X-ray fluorescence spectrometer to obtain the concentration of the fluorine-containing drug.

2. The method for detecting fluorine content in drugs based on X-ray fluorescence spectroscopy according to claim 1, characterized in that: The graphene oxide dispersion is added into the aqueous solution of the fluorine-containing drug, and an ion flocculant is added into the solution.

3. The method for detecting fluorine content in drugs based on X-ray fluorescence spectroscopy according to claim 2, characterized in that: The ionic flocculants include aluminum nitrate and calcium chloride.

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