Natamycin Container Price,residue detection

The main methods for detecting the residual amount of natamycin in food are as follows:

I. High Performance Liquid Chromatography (HPLC)

Principle: It uses the difference in the distribution coefficient of natamycin between the stationary phase and the mobile phase for separation, and then conducts quantitative analysis through a detector.

Operation Process: First, extract the food sample. Generally, solvents such as methanol-water are used for extraction. After the extract undergoes pretreatment processes such as filtration and concentration, it is injected into the high-performance liquid chromatograph. The chromatographic column usually selects a C18 column, and the mobile phase commonly uses a mixed solution of methanol-water or acetonitrile-water. By adjusting the proportion and flow rate of the mobile phase, natamycin can be well separated. The detector generally uses an ultraviolet detector, and the detection wavelength is usually between 230 - 300nm. The content of natamycin in the sample is calculated according to the standard curve.

Advantages: It has the advantages of good separation effect, high sensitivity, and strong accuracy. It can simultaneously detect the residual amount of natamycin in various foods, and can effectively separate and quantify natamycin in complex samples.

Disadvantages: It requires professional instruments and equipment as well as operators. The sample pretreatment process is relatively complicated, and the analysis cost is high.

II. Thin Layer Chromatography (TLC)

Principle: Spot the sample solution on the thin layer plate, and use the adsorption and distribution of natamycin on the thin layer plate for separation. Then, develop color with a color-developing agent and compare it with the standard substance to determine the content of natamycin in the sample.

Operation Process: First, extract the food sample with an appropriate solvent. After concentrating the extract, spot it on a thin layer plate such as silica gel G. Use chloroform-methanol-water, etc. as the developing agent and develop it in a developing tank. After development, dry the thin layer plate, develop color with a color-developing agent such as sulfuric acid-ethanol, and observe the position and color of the spots. By comparing with the spots of the natamycin standard substance developed under the same conditions, the content of natamycin in the sample is determined.

Advantages: The operation is relatively simple, it does not require complex instruments and equipment, the cost is low, and it is suitable for on-site rapid detection and preliminary screening.

Disadvantages: The sensitivity is relatively low, the accuracy is not as good as that of high-performance liquid chromatography, and it can only conduct semi-quantitative analysis. It may not be able to accurately detect samples with a low content.

III. Enzyme-Linked Immunosorbent Assay (ELISA)

Principle: Utilize the specific binding reaction of antigen-antibody. Take natamycin as the antigen, prepare the corresponding antibody, label the antibody with an enzyme, bind it to the natamycin in the sample, then add the substrate. The substrate is colored through the enzymatic catalysis, and the content of natamycin is quantitatively analyzed according to the shade of the color.

Operation Process: First, coat the natamycin antigen on the microplate. Add the sample solution and the enzyme-labeled antibody, incubate and then wash to remove the unbound substances. Then add the substrate solution, react for a certain period of time, finally add the stop solution, and measure the absorbance value with a microplate reader. The content of natamycin in the sample is calculated according to the standard curve.

Advantages: It has high sensitivity, strong specificity, simple and rapid operation, and is suitable for the screening detection of a large number of samples.

Disadvantages: It is necessary to prepare specific antibodies, the cost of the kit is high, and there may be cross-reactions, which have a certain impact on the accuracy of the results.