Liquid chromatography detection method for cyanide residues in injection
By using liquid chromatography with taurine and 2,3-naphthaldehyde aqueous solution as derivatization reagents in injection solutions, the problem of detecting cyanide residues in injection solutions has been solved, achieving high sensitivity and specificity in detection and meeting the needs of drug safety control.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-03-13
AI Technical Summary
Existing technologies are insufficient for efficiently and accurately detecting cyanide residues in injection solutions, especially at low concentrations, and suffer from false positives and insufficient sensitivity.
Water was used as the solvent, and taurine aqueous solution and 2,3-naphthialdialdehyde aqueous solution were used as derivatization reagents. The reaction was carried out at room temperature, and the reaction was combined with liquid chromatography, with gradient elution and DAD detector for detection. The chromatographic column and mobile phase conditions were optimized.
It achieves highly sensitive, accurate, and specific detection of cyanide residues in injection solutions, with a quantitation limit as low as 0.6 ng/mL, meeting drug safety control requirements, simplifying the operation process, and improving detection efficiency and accuracy.
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Figure CN121656435A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of pharmaceutical analysis technology, specifically to a liquid chromatography method for detecting cyanide residues in injectable solutions. Background Technology
[0002] Drug impurities are undesirable chemical components present in active pharmaceutical ingredients (APIs, raw materials) or drug formulations. Impurities in injectable solutions may originate from the synthesis process or starting materials, intermediates, solvents, catalysts, reaction byproducts, instability of the injectable solution composition, incompatibility with excipients, or reactions with packaging materials, etc. Various impurities in drugs have a significant impact on the safety of the final drug. These impurities directly affect drug safety, with genotoxic impurities (GTIs) posing a particularly prominent risk. These impurities can directly damage cellular DNA, inducing gene mutations or mutagenesis in vivo, and have potential carcinogenicity; their core hazard is "effective at low concentrations"—even at extremely low concentrations, they can damage human genetic material, thereby inducing gene mutations and even increasing the risk of tumor development, posing a serious threat to drug safety.
[0003] Cyanide has a wide range of applications, covering multiple industries such as pharmaceuticals, pesticides, papermaking, and textiles. However, it is a highly toxic substance—even trace amounts can inhibit the activity of metalloenzymes and non-metalloenzymes in the body, leading to lesions in the vascular, gastrointestinal, visual, endocrine, central nervous, and metabolic systems. Its toxic mechanism is clear: after entering the human body, cyanide dissociates into CN... - (Cyanide ion). This ion can react with Fe in the terminal respiratory chain enzyme (cytochrome oxidase aa3). 3+ The binding of ferric ions (Fe3+) causes enzymes to lose activity. This process directly interrupts intracellular respiration, blocks electron transport and oxidative phosphorylation, and fundamentally inhibits the synthesis of adenosine triphosphate (ATP). ATP is a core source of cellular energy; its inhibition prevents cells from utilizing oxygen, leading to tissue hypoxia and ultimately acute poisoning. Given the high toxicity and clear hazards of cyanide, strict testing and control of cyanide content in finished drugs and pharmaceutical intermediates are essential throughout the entire drug production process to ensure medication safety.
[0004] Cyanide can generally be detected by spectrophotometry, gas chromatography-electron capture detector (GC-Effect Detection Detection), ion chromatography, and fluorescence methods. The isonicotinic acid-pyrazolone spectrophotometric method is susceptible to contamination in practical applications and has limitations due to its complex operation, making it unsuitable for detecting cyanide residues in injectable solutions. Derivatized GC-Effect Detection Detection Detection (DEGC-Effect Detection ... Summary of the Invention
[0005] (a) Technical problems to be solved: To address the shortcomings of existing technologies, this invention provides a liquid chromatography method for detecting cyanide residues in injection solutions, thus solving the problems mentioned in the background section.
[0006] (II) Technical Solution: To achieve the above objectives, the present invention provides the following technical solution: a liquid chromatography method for detecting cyanide residues in an injection solution, using water as a solvent and taurine aqueous solution and 2,3-naphthodialdehyde aqueous solution as derivatizing reagents. The cyanide reacts with the taurine aqueous solution and the 2,3-naphthodialdehyde aqueous solution at room temperature. The liquid chromatography detection method includes the following steps: S01. Prepare the reference solution and sample solution; S02, HPLC detection: An octadecylsilane-bonded silica gel column was used as the stationary phase; acetonitrile-ammonium formate aqueous solution was used as the mobile phase; a DAD detector was used; a gradient elution program was performed, wherein the gradient elution program was selected from any of the following programs: (1) The initial acetonitrile ratio is 30%, and it is maintained for 1.5 minutes. Then, it is increased to 80% within 6.5 minutes and maintained for 3 minutes. Then, it is reduced back to 30% and maintained for 5 minutes. The flow rate is 0.3 mL / min. (2) The initial acetonitrile ratio is 30%, and it is maintained for 3 minutes. Then, it is increased to 80% within the next 5 minutes and maintained for 7 minutes. Then, it is reduced back to 30% and maintained for 5 minutes. The flow rate is 0.3 mL / min. S03. Result Calculation: Inject multiple reference solutions and injection sample solutions sequentially according to the chromatographic conditions in step S02, record the DAD spectrum, plot a linear correlation working curve based on the chromatographic data and concentration data of multiple reference solutions, substitute the chromatographic data of the injection sample into the working curve and calculate the residual concentration of reference in the sample, thereby completing the determination of cyanide residue in the injection.
[0007] Preferably, the cyanide is potassium tetracyanozincate.
[0008] Preferably, in step S01, the specific preparation method of the reference solution and the sample solution is as follows: accurately transfer potassium tetracyanozincate reference standard, add 5 mmol / L taurine aqueous solution, then add 1 mmol / L 2,3-naphthodialdehyde aqueous solution, dilute with water and make up to volume to prepare multiple reference solutions with concentration gradients; accurately weigh the injection sample, add taurine aqueous solution, then add 2,3-naphthodialdehyde aqueous solution, dilute with water and make up to volume to obtain the sample solution.
[0009] Preferably, the concentrations of the reference solutions are 0.6, 6, 21, 30, and 150 ng / mL, respectively.
[0010] Preferably, in step S02, the concentration of the ammonium formate aqueous solution is 10 mmol / L to 30 mmol / L, and its pH value is 3.5 to 5.5.
[0011] Preferably, in step S02, the chromatographic column is a Poroshell 120 EC-C18 2.7µm 4.6 mm column. 100mm.
[0012] Preferably, in step S02, the injection volume is 5 μL to 100 μL.
[0013] Preferably, in step S02, the detection wavelength is 235nm~255nm.
[0014] Preferably, in step S02, the column temperature is 30℃~45℃.
[0015] Preferably, in step S02, the column temperature is 40°C.
[0016] (III) Beneficial Effects: This invention provides a liquid chromatography method for the detection of cyanide residues in injectable solutions. Compared with existing technologies, it has the following advantages: (1) In this invention, by using taurine aqueous solution and 2,3-naphthialdialdehyde aqueous solution as a combined derivatization reagent, cyanide can undergo a mild, rapid and complete derivatization reaction at room temperature without the need for complex reaction conditions or subsequent extraction steps, effectively avoiding problems such as interference from derivatization reagents and incomplete reaction in traditional methods. At the same time, the derivatized product can be specifically identified, and combined with the precise response of the DAD detector, the interference of excipients and other impurities in the injection solution can be effectively eliminated, ensuring the specificity and accuracy of the detection results, perfectly meeting the precise screening needs of genotoxic impurities.
[0017] (2) In this invention, the method has a quantitation limit as low as 0.6 ng / mL, and the corresponding signal-to-noise ratio reaches 12, which far exceeds the quantitation limit standard stipulated in the Chinese Pharmacopoeia. It can accurately capture extremely low concentrations of cyanide residues in the injection solution, completely cover the risk control scenario of "low concentration is effective" of genotoxic impurities, and provide core technical guarantee for drug safety.
[0018] (3) In this invention, the peak area of cyanide derivatives is strongly linearly correlated with concentration in the concentration range of 0.6~150ng / mL, covering the entire scenario of low, medium and high residual concentration in actual detection. It can achieve accurate quantification of samples with different levels of pollution without multiple adjustments to detection parameters, and significantly improve detection efficiency.
[0019] (4) In this invention, by specifically optimizing the chromatographic column, mobile phase, gradient elution program, and detection wavelength, the chromatographic baseline is stable without drift, the target peak is symmetrical, and the separation is good. The detection wavelength of 250 nm is precisely matched with the strong ultraviolet absorption characteristics of the derivatized product, maximizing the signal intensity and reducing background interference. At the same time, the derivatized solution has good stability within 40 h, eliminating the need for immediate preparation and testing, reducing operational complexity, and improving the operability of practical applications.
[0020] In summary, the detection method of this invention can effectively detect cyanide residues in injection solutions, with a limit of quantification of 0.6 ng / mL. Compared with existing direct injection and derivatization methods, the sample preparation process is simple, the operation is safe and easy, the processing is convenient and fast, the detection efficiency is improved, the equipment is readily available, the chromatographic baseline is stable and does not drift, and there is less interference from the DAD detector, thus improving the precision and accuracy of the method. For the determination of cyanide residues, it exhibits good sensitivity, linearity, precision, accuracy, and stability, and has significant research value in the study of injection solution quality and impurity analysis and control. Attached Figure Description
[0021] Figure 1 This is a specific chromatogram of the cyanide solution in an embodiment of the present invention; Figure 2 The above are liquid chromatograms of blank solution, reference solution and 100% accuracy injection solution in the embodiments of the present invention; Figure 3 The working curve of the linear test in the embodiments of the present invention; Figure 4 This is the ultraviolet chromatogram of the cyanide solution in an embodiment of the present invention. Detailed Implementation
[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0023] The cyanide detection method provided by this invention uses water as a solvent and taurine aqueous solution and 2,3-naphthodialdehyde aqueous solution as derivatizing reagents. The inventors discovered that the reaction of cyanide with taurine aqueous solution and 2,3-naphthodialdehyde aqueous solution is mild, rapid, and complete at room temperature, requiring no complex derivatizing reagents or extraction; the solution can be directly detected after preparation. This method is applicable to all water-soluble injection solutions. This invention uses potassium tetracyanozincate as an example. Other cyanide types can also be applied to the method described in this invention, including the following steps: (1) Preparation of reference solution and sample solution: Accurately transfer an appropriate amount of potassium tetracyanozincate reference standard, add 1 mL of taurine aqueous solution (5 mmol / L), then add 1 mL of 2,3-naphthodialdehyde aqueous solution (1 mmol / L), dilute with water and make up to volume to prepare multiple reference solutions with concentration gradient; accurately weigh an appropriate amount of injection sample, add 1 mL of taurine aqueous solution, then add 1 mL of 2,3-naphthodialdehyde aqueous solution, dilute with water and make up to volume to obtain sample solution; (2) HPLC method conditions: The chromatographic column used was a Poroshell 120 EC-C18 2.7µm 4.6. 100mm; Gradient elution 1 was used, with an initial acetonitrile ratio of 30%, held for 1.5 minutes, then increased to 80% over the next 6.5 minutes and held for 3 minutes, followed by a decrease to 30% and held for 5 minutes. The flow rate was 0.3 mL / min, the injection volume was 5 μL, the column temperature was 40 °C, and a DAD detector was used with a detection wavelength of 250 nm.
[0024] Gradient elution 2 was used, with an initial acetonitrile ratio of 30% held for 3 minutes, then increased to 80% and held for 7 minutes over the next 5 minutes, followed by a decrease to 30% and held for 5 minutes. The flow rate was 0.3 mL / min, the injection volume was 20 μL, the column temperature was 40 °C, and a DAD detector was used with a detection wavelength of 250 nm.
[0025] (3) Calculation of results: The multiple reference solutions and sample solutions are injected sequentially under the chromatographic conditions of step (2), and the chromatograms are recorded. A linear correlation working curve is prepared based on the chromatographic data and concentration data of the multiple reference solutions. The chromatographic data of the sample is substituted into the curve to calculate and obtain the concentration of the sample solution, thus completing the determination of cyanide residue.
[0026] Example 1: Specificity study for the determination of cyanide residues in injection solutions: Accurately transfer 1 mL of potassium tetracyanozincate aqueous solution containing 200 ng / mL cyanide, add 1 mL of 5 mmol / L taurine aqueous solution, then add 1 mL of 1 mmol / L 2,3-naphthodialdehyde aqueous solution, dilute with water and bring the volume to 10 mL, and label it as cyanide reaction solution.
[0027] HPLC analysis of the cyanide reaction solution was performed under the following conditions: The chromatographic column used was a Poroshell 120 EC-C18 2.7µm 4.6. 100mm; Gradient elution was performed with an initial acetonitrile concentration of 30%, held for 1.5 minutes, then increased to 80% over the next 6.5 minutes and held for 3 minutes, followed by a decrease to 30% and held for 5 minutes. The flow rate was 0.3 mL / min, the injection volume was 5 μL, the column temperature was 40 °C, and a DAD detector was used with a detection wavelength of 250 nm. The DAD spectrum of the cyanide-reaction solution is as follows: Figure 1 As shown, cyanide was completely converted after 1 mL of taurine aqueous solution was added to 1 mL of 2,3-naphthialdialdehyde aqueous solution. This derivatization reaction was mild, rapid and complete. The peak shape of the target derivatized product was clear and there were no interfering peaks. This indicates that the method can specifically identify cyanide derivatized products, effectively eliminate interference from other components in the injection solution (such as excipients and other impurities), accurately lock the target analyte, and meet the core requirement of "specific identification" in drug impurity detection.
[0028] Example 2: Sensitivity and linearity studies for the determination of cyanide residues in injection solutions: Accurately transfer 1 mL of 3 µg / mL cyanide solution into a 10 mL volumetric flask, dilute to the mark with aqueous solution, and shake well. Label this as reference stock solution 1.
[0029] HPLC analytical method conditions: The chromatographic column used was a Poroshell 120 EC-C18 2.7µm 4.6. 100mm; Gradient elution 2 was used, with an initial acetonitrile ratio of 30% held for 3 minutes, then increased to 80% and held for 7 minutes over the next 5 minutes, followed by a decrease to 30% and held for 5 minutes. The flow rate was 0.3 mL / min, the injection volume was 20 μL, the column temperature was 40 °C, and a DAD detector was used with a detection wavelength of 250 nm.
[0030] Sensitivity test: Accurately transfer 1 to 10 mL of the 0.02 mL reference standard stock solution into a volumetric flask, add 1 mL of taurine aqueous solution, then add 1 mL of 2,3-naphthial dialdehyde aqueous solution, dilute with water and bring to volume, and label as sensitivity solution (0.6 ng / mL).
[0031] In the DAD chromatogram of the sensitivity solution test, the signal-to-noise ratio of the target peak cyanide was 12, which fully meets the requirements of the limit of quantitation (S / N≥10) in the Chinese Pharmacopoeia.
[0032] Linearity test: Accurately transfer 0.02 mL, 0.2 mL, 0.7 mL, 1.0 mL, and 5 mL of the reference stock solution into 1 to 5 10 mL volumetric flasks, add 1 mL of taurine aqueous solution, then add 1 mL of 2,3-naphthial dialdehyde aqueous solution, dilute with water, and bring to volume. The concentrations of the obtained linearity test solutions are 0.6, 6, 21, 30, and 150 ng / mL, respectively.
[0033] In the DAD chromatogram for linearity testing, the linear equation for the peak areas of the five test solutions at different concentrations is Y = 23.71X - 38.72, with a linear correlation coefficient r = 0.9993. This demonstrates that this method exhibits good linearity for cyanide testing within the range of 0.6 ng / mL to 150 ng / mL. Figure 3 ).
[0034] Depend on Figure 3 It can be seen that within the concentration range of 0.6~150ng / mL, the peak area is strongly linearly correlated with the concentration; and this concentration range covers the entire scenario of "low residue, medium residue, and high residue" in actual detection. The working curve can accurately quantify injection samples with different levels of contamination without having to adjust the concentration range multiple times, thus improving detection efficiency.
[0035] Example 3: Precision, accuracy, and stability study of cyanide residue determination in injection solutions: Accurately transfer 1 mL of 2 µg / mL cyanide solution into a 10 mL volumetric flask, dilute to the mark with aqueous solution, and shake well. Label this as reference stock solution 2.
[0036] HPLC analytical method conditions: The chromatographic column used was a Poroshell 120 EC-C18 2.7µm 4.6. 100mm; Gradient elution 1 was used, with an initial acetonitrile ratio of 30%, held for 1.5 minutes, then increased to 80% over the next 6.5 minutes and held for 3 minutes, followed by a decrease to 30% and held for 5 minutes. The flow rate was 0.3 mL / min, the injection volume was 5 μL, the column temperature was 40 °C, and a DAD detector was used with a detection wavelength of 250 nm.
[0037] Precision testing: Accurately transfer 1.0 mL of the reference stock solution into a 10 mL volumetric flask, add 1 mL of taurine aqueous solution, then add 1 mL of 2,3-naphthial dialdehyde aqueous solution, dilute with water and bring to volume, and label as reference solution (20 ng / mL).
[0038] Six consecutive injections of the reference solution were performed. In the DAD chromatograms, the relative standard deviations (RSDs) of the retention times of cyanide in the six reference solutions were 0.04%, and the relative standard deviations (RSDs) of the peak areas of cyanide in the six reference solutions were 0.5%. This demonstrates that the method has excellent precision.
[0039] Accuracy test: Nine 1 mL aliquots of the injection sample with known cyanide residue were precisely transferred to 5 mL volumetric flasks. 0.25 mL, 0.50 mL, and 0.75 mL of 1000% (200 ng / mL) stock solution 2 of reference standard were added, followed by 1 mL of taurine aqueous solution, then 1 mL of 2,3-naphthaldehyde aqueous solution. The solutions were diluted with water and brought to volume, labeled as 50%, 100%, and 150%, respectively. Three recoveries were prepared for each type of recovery solution for testing. The overlay plot of the reference solution and accuracy solution is shown below. Figure 2 The recovery rates of the nine solutions are shown in Table 1 below. This demonstrates that the method has good accuracy.
[0040] Table 1
[0041] Depend on Figure 2 As can be seen from the chromatographic comparison of the blank solution and the reference solution in Figure 2, the target peak signal is clear and the signal-to-noise ratio (S / N=12) is higher than the limit of quantitation (S / N≥10) specified in the Chinese Pharmacopoeia. This indicates that the method can accurately detect extremely low concentrations of cyanide residues and can effectively control the safety risk of genotoxic impurities taking effect at low concentrations. Figure 2 The chromatographic baseline of the blank solution was stable and without drift, and the target peaks of the reference solution and the accuracy solution for injection were sharp and without tailing, proving that the DAD detector had little interference and the detection system had excellent stability, providing a reliable guarantee for low-concentration detection.
[0042] Figure 2 As shown in Table 1, after six consecutive injections of the 20 ng / mL reference solution, the retention time RSD was 0.04% and the peak area RSD was 0.5%, which are far below the allowable deviation of conventional detection methods (generally RSD ≤ 5%). Figure 2 The consistent peak shape across multiple injections demonstrates excellent instrument repeatability, operational stability, and controllable error of the method.
[0043] In summary, the data in Table 1 shows that the recovery rates at the three levels of 50%, 100%, and 150% ranged from 88.1% to 103.8%, with an average recovery rate of 97.38% and an RSD of 4.7%, which meets the industry standard of "recovery rate of 80% to 120%" for drug impurity detection. Figure 2 The target peak of the 100% accuracy solution for injection was consistent with that of the reference solution in terms of peak shape and retention time, with no additional interference. This indicates that the method can accurately reflect the actual residual amount of cyanide in the sample without systematic error.
[0044] Stability test: The same reference solution (10 ng / mL) was injected at 0 h and 40 h for determination. The results showed that the ratio of the cyanide peak area at 40 h to the cyanide peak area at 0 h was 108%, indicating that the reference solution was stable within 40 h.
[0045] Depend on Figure 4 It is known that there is strong absorption in the wavelength range of 235~255nm, with the highest absorption intensity at 250nm, which perfectly matches the detection wavelength (250nm) set by the method. This wavelength selection can maximize the target peak signal and minimize background interference, further ensuring the sensitivity and accuracy of the detection, and verifying the scientific nature of the detection condition design.
[0046] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.
[0047] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A liquid chromatography method for detecting cyanide residues in an injection solution, characterized in that, Using water as a solvent, and taurine aqueous solution and 2,3-naphthodialdehyde aqueous solution as derivatizing reagents, the reaction of cyanide with taurine aqueous solution and 2,3-naphthodialdehyde aqueous solution is carried out at room temperature. The liquid chromatography detection method includes the following steps: S01. Prepare the reference solution and sample solution; S02, HPLC detection: An octadecylsilane-bonded silica gel column was used as the stationary phase; acetonitrile-ammonium formate aqueous solution was used as the mobile phase; a DAD detector was used; a gradient elution program was performed, wherein the gradient elution program was selected from any of the following programs: (1) The initial acetonitrile ratio is 30%, and it is maintained for 1.5 minutes. Then, it is increased to 80% within 6.5 minutes and maintained for 3 minutes. Then, it is reduced back to 30% and maintained for 5 minutes. The flow rate is 0.3 mL / min. (2) The initial acetonitrile ratio is 30%, and it is maintained for 3 minutes. Then, it is increased to 80% within the next 5 minutes and maintained for 7 minutes. Then, it is reduced back to 30% and maintained for 5 minutes. The flow rate is 0.3 mL / min. S03. Result Calculation: Inject multiple reference solutions and injection sample solutions sequentially according to the chromatographic conditions in step S02, record the DAD spectrum, plot a linear correlation working curve based on the chromatographic data and concentration data of multiple reference solutions, substitute the chromatographic data of the injection sample into the working curve and calculate the residual concentration of reference in the sample, thereby completing the determination of cyanide residue in the injection.
2. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: The cyanide is potassium tetracyanozincate.
3. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S01, the specific preparation methods for the reference solution and the sample solution are as follows: accurately transfer potassium tetracyanozincate reference standard, add 5 mmol / L taurine aqueous solution, then add 1 mmol / L 2,3-naphthodialdehyde aqueous solution, dilute with water and make up to volume to prepare multiple reference solutions with concentration gradients; accurately weigh the injection sample, add taurine aqueous solution, then add 2,3-naphthodialdehyde aqueous solution, dilute with water and make up to volume to obtain the sample solution.
4. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 3, characterized in that: The concentrations of the reference solutions were 0.6, 6, 21, 30, and 150 ng / mL, respectively.
5. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the concentration of the ammonium formate aqueous solution is 10 mmol / L to 30 mmol / L, and its pH value is 3.5 to 5.
5.
6. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the chromatographic column is a Poroshell 120 EC-C18 2.7µm 4.
6. 100mm.
7. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the injection volume is 5 μL to 100 μL.
8. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the detection wavelength is 235nm~255nm.
9. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the column temperature is 30℃~45℃.
10. The liquid chromatography method for detecting cyanide residues in an injection solution according to claim 1, characterized in that: In step S02, the column temperature is 40°C.