SN/T 5151-2019 in English

Technical background and significance of the standard

As a mandatory inspection procedure issued by the General Administration of Customs in 2019, this standard establishes a systematic detection method for 7 potential photosensitizing benzophenone derivatives in sunscreen cosmetics. As common ultraviolet absorbers, excessive use of benzophenones may cause skin allergic reactions. EU Cosmetics Regulation (EC) No 1223/2009 has set limit requirements for some substances.

Core detection principle

Baseline separation of 7 structurally similar substances is achieved by using a high performance liquid chromatograph combined with a UV detector through a gradient elution program. The technical routes include:

1. Tetrahydrofuran-methanol mixed solvent extraction
2. C18 reverse phase chromatography column separation (250mm×4.6mm, 5μm)
3. External standard method quantification (0.5-20μg/mL linear range)
4. LC-MS/MS positive result confirmation

Comparison of key operating parameters

Method Validation Data

Recommendations for the implementation of the standard

1. Pretreatment optimization: For physical sunscreen products containing titanium dioxide, it is recommended to add 10 minutes of centrifugation (12000rpm) to remove particle interference

2. Quality control points: Each batch of testing should include blank controls, matrix spikes and parallel samples. It is recommended to use isotope internal standards (such as dibenzophenone-d10) to correct for matrix effects

3. Equipment maintenance: The C18 column needs to be rinsed with 95% acetonitrile for 30 minutes after every 100 injections to keep the column efficiency stable