1 Tổng quan phương pháp
After sample pretreatment, lead ions form a complex with sodium diethyldithiocarbamate (DDTC) under a specific pH condition. The complex is extracted and separated using 4-methyl-2-pentanone (MIBK), then introduced into an atomic absorption spectrometer for flame atomization. Absorbance is measured at a wavelength of 283.3 nm. Within a certain concentration range, the absorbance of lead is proportional to its mass content, and quantification is performed by comparison with a standard series.
2. Phạm vi áp dụng
This method applies to the determination of lead in sodium pyrophosphate food additive.
3 Reference Standards
GB 25557-2010 National Food Safety Standard – Food Additive Sodium Pyrophosphate, Section A.10 Determination of Lead
4 Instruments, Equipment and Reagents
4.1 Dụng cụ và thiết bị
4.1.1 Analytical Instruments
表格
| Không. | Tên | Số lượng | Yêu cầu kỹ thuật | Phụ kiện |
| 1 | Máy quang phổ hấp thụ nguyên tử ngọn lửa | 1 bộ | — | Đèn cathode rỗng chì |
| 2 | Máy nén khí | 1 đơn vị | Áp suất khí thải định mức: 0,3 MPa | — |
| 3 | Acetylene Cylinder | 1 xi lanh | Độ tinh khiết ≥ 99,99% | — |
