Portable pesticide residue rapid detecting apparatus

Pesticide residue rapid detecting apparatus is designed specially according to rapid detecting card. It is suitable for rapid detection of pesticide residue of organophosphorus and carbamate in the field of fruit, vegetable, tea, food, water and soil.

1. Principle

The principle of this apparatus is to utilize the inhibition function of cholinesterase in the detecting card to organophosphorus and carbamate. Generally, cholinesterase on the white pill will catalyze indophenol acetate on the red pill to form acetic acid and indophenol. However, organophosphorus pesticide and carbamate pesticide will inhibit the activity ofcholinesterase, and make chromogenic reaction change. Therefore according to the color of chromogenic reaction, can make sure whether there is any organophosphorus pesticide residue or carbamate pesticide residue.

2. Using method

2.1  Start the apparatus

Press [on/off] button on the operating panel for 3s to turn it on. ( Press this button again to turn it off); Press [pattern] key to switch to “temperature”, then press “setting” to turn up or down. When the temperature reaches 40℃ , the apparatus will buzz , it means that the pre-heating is finished and the test can be started. (The temperature of factory setting is 40℃)

2.2  Place the detecting card in the groove of the apparatus

Fold the detecting card after ripping out the film of the card, and then insert them in the grooves of the heating plates. The red pill should be placed upward, and the white pill should be placed downward. Check whether the position of rapid detecting card is correct, and make sure dotted line in the middle of the card is in line with the pressing mound layer.

2.3  Sampling

Choose representative vegetable or fruit peel, and wipe off the dirt on the surface. Cut them into about 1cm² small pieces. Select 5g of them into the bottle. Add 10ml pure water or buffer solution, and then put it in the ultrasonic cleaning machine to mix them for 2min. (Or stir them with a glass rod or shake the bottle with hand for 2min).It is better to do 11 tests for each testing sample, and at the same time do a blank control test with pure water or buffer solution. The knife should be cleaned carefully after cutting one sample and before cutting another sample in order to avoid cross-contamination. Suck 80μg sample solution with pipette and drop them on the white pill.

If the test is proceeded on the spot or in primitive environment, eluent can be dropped on the top part of vegetable leaf. And then use another leaf to rub it at the part which is dropped the eluent to make the residue pesticide dissolve into the eluent. Then drop the solution on the white pill.

2.4  Test

Press "Star" key for reaction about 10min without covering the lid. When hearing buzz, cover the lid of the apparatus. After 3mins "color" indicator lights on. When hearing buzz again, open the lid of the apparatus and make the determination.

3.  Specification

Testing channel: 12

Constant temperature : 40℃

Time of reaction：10mins

Chromogenic time: 3mins

Optional range : 30-50℃ for constant temperature

1-99mins ajustable for reaction time

1-99mins ajustable for chromogenic time

Power supply: input 100-240VAC, 50/60HZ, 0.8A

              output12VDC

Build-in chargeable lithium battery: 7.4V/2000mA

Working time: about three and a half hours at 20℃-25℃.

Charge/discharge: about 500 times