Instructions for use: It can be used for the pre-treatment of sulfur dioxide residues in Chinese medicinal materials and slices in the methods specified in the Chinese Pharmacopoeia.
The 2015 edition of the Chinese Pharmacopoeia stipulates three methods for detecting sulfur dioxide: acid-base titration, gas chromatography, and ion chromatography. Gas chromatography and ion chromatography have the advantages of high sensitivity and strong specificity, but the instruments and equipment are expensive, which is not conducive to the promotion and use of grassroots drug testing systems; acid-base titration has the advantages of simple equipment and low cost, and is a statutory detection method stipulated in the Pharmacopoeia. However, since the Pharmacopoeia only describes the glass instrument device of this method, the purchase, assembly and implementation of the entire set of equipment still need to be continuously improved. For example: (1) In addition to the glass instrument device, it is also necessary to equip it with a magnetic stirrer, an electric heating jacket, a titration platform, a nitrogen device with a flow meter, etc., and assemble them. Many units feel that it is cumbersome to purchase too many equipments and difficult to assemble and implement, so they are unable to carry out this test method; (2) The assembled devices are varied and there are problems such as unstable nitrogen flow rate, uneven heating, easy leakage, easy boiling, and easy to be affected by cooling water source during use, which directly affect the test results, such as poor parallelism and low recovery rate; (3) The work efficiency is low. The current equipment uses a single-unit device, which is difficult to process multiple samples at the same time. It is time-consuming and laborious to test multiple batches of medicinal materials at the same time.

Instrument innovation
(1) Heating, distillation reflux, cooling, nitrogen blowing control, magnetic stirring, and receiving six-in-one design;
(2) The closed cooling water automatic cooling and circulation reflux device does not require external tap water cooling, thus saving energy and reducing consumption;
(3) Using far-infrared ceramic heating device instead of ordinary electric heating furnace or electric heating jacket, it is more energy-saving, waterproof and resistant to acid and alkali corrosion;
(4) 4 groups of samples can be processed at one time, and the heating power can be adjusted by single hole (knob type);
(5) With additional nitrogen protection function, the nitrogen blowing flow rate can be adjusted independently by single hole (60-600ml/min);
(6) Reflux condenser design according to the original drawing of Chinese Pharmacopoeia
(7) A magnetic stirrer is built into the bottom of the receiving bottle, and the stirring speed can be adjusted by a single group;

* ST107-1RW is a high-end version, with the following new features:
① Different cooling methods: using compressor + air cooling dual cooling mode, the cooling effect is good, suitable for continuous batch processing of samples, and is not affected by room temperature;
② Newly added anti-dry burning design and thermal overload protection to prevent the flask from cracking and drying out;
③ New automatic timing function, according to the requirements of the pharmacopoeia, the instrument can automatically count down and heat, and stop automatically when the time is up;
④ New micro-boiling heating system makes the sample heated more evenly and the detection structure more reliable

Applicable units and test items:
All levels of TCM inspection and testing, TCM R&D and production enterprises, TCM and other units that need to test the sulfur dioxide residue in TCM, medicinal materials and decoction pieces