First, the pesticide residue fast detector main uses
Pesticide residue Speed Tester is based on national standard method GB / T5009.199-2003 (vegetables in rapid detection of organophosphorus and carbamate pesticide residues) in the speed test card method (disk diffusion method) and specially designed instrument mainly used for fruit, vegetables, tea, food, water, and soil organic phosphorus and carbamate pesticides rapid detection, especially for the rapid detection of agricultural products quality inspection station; fruit and vegetable production bases and specialist fields before picking detection; Farmers wholesale market scene detection; security detection restaurants, canteens, family fruits and vegetables, tea processing ago.
Second, rapid detection of pesticide residues in principle
Instrument detection principle is to use speed measurement card cholinesterase (white tablet) catalyzes the indophenol acetate (red tablets) hydrolyzed to acetic acid and indophenol, as organophosphate and carbamate pesticides on cholinesterase inhibit enzyme activity, so the color change after catalyzed hydrolysis, thus depending on the color, you can determine the sample contains residual phosphorus or carbamate situation pesticides.
This product is designed for factory setting temperature is 40 ℃, to ensure full hydrolysis of cholinesterase and indophenol acetate, using SCM control and precision temperature sensor temperature accuracy, keep the temperature stable at 40 ℃; using high-precision clock chip precision time control of the instrument to ensure that the reaction time and color.
Third, the pesticide residue fast detector main performance parameters and specifications
Pesticide residue fast detector Model
Number of measuring channels
Factory setting temperature
40 ℃ (30 ~ 50 ℃ adjustable)
10 minutes (1 to 99 minutes adjustable)
3 minutes (1 to 99 minutes adjustable)
Fifth, the pesticide residue fast detector basic functions
1, apparatus for heating, temperature and timing, speed test card can be heated to a constant temperature 40 ℃; the instrument has 12 channels, which can detect 12 samples.
2, the instrument with removable stainless steel pressure paper round: Round stainless steel pressure strip speed measurement card for easy insertion and removal, stainless steel strip after pressure Removable cleaning contaminated thereby increasing the measurement accuracy.
3. Key Function
<switch> Key: In the off state, press <ON / OFF> key for about 3 seconds on, in working condition, press <ON / OFF> key is off.
<mode> Key: Press <mode> key to toggle the display and settings, continuous press <mode> to turn the LCD display real-time 'temperature' reaction time ', the color of time'.
Note : Boot page defaults to 'clock' mode.
<Settings> Key: In the display mode, press the 'set' button to display the items on the current settings, turn down the first significant page mode, press the 'set' to adjust the current clock, the 'model' to display the next item and press the 'Settings' can be real-time' temperature 'reaction time', the color of time 'value is adjusted by <•>, <> to adjust the corresponding argument, press the <set> key to automatically save and exit setting mode. <•> <> key: value increase, decrease key in setting mode, press <•>, <> keys to adjust the corresponding value.
<start up> Key: When the instrument is heating thermostat to 40 ℃, press <Start> key test timer starts, the test process by pressing <Start> button to cancel the test.
Sixth, the pesticide residue fast detector Procedure
1, start and set up:
Hold down the top panel < switch > Button for about three seconds, the instrument is switched (turned on and hold this button for about 3 seconds for the shutdown); press < mode > Button LCD display symbols corresponding to 'temperature', then 'Settings' press <•>, <> adjust the temperature to the desired temperature, then press the 'set' button to save the settings (instrument factory setting is 40 ℃), when When the temperature reached 40 ℃, the instrument emits a 'drop' sound alerts, which can start a normal test.
2 rapid detection of pesticide residue speed measurement card is installed:
The speed measurement card and then fold unfold, tear the cover film, the channel strip is inserted under pressure hotplate (Note that at the top end of the red pills, white pills at one end at the bottom) Check-speed measurement card is placed in the correct position, speed test card in the middle of a broken line should align with the layering, not skewed.
3, the sample processing:
Wipe the surface of the soil or fruit and vegetable debris, choose a representative pointed leaves or fruit leather 5 g, placed in a small beaker with scissors about 1cm square pieces, add 10 ml of buffer or pure water, placed in an ultrasonic cleaner shock two minutes (if no ultrasonic cleaning can stir with a glass rod or hand shaking the vial for about two minutes, so that leaves with the water full contact), each batch is recommended to do 11 test sample, at the same time make a buffer or pure water blank. Every hair cut a sample before treatment should be washed scissors another sample, in order to avoid mutual contamination. Pipette 2-4 drops of the sample solution is applied to speed measurement card of white pills tested. If it is detected at the sampling site or in poor condition situation, can drop 2--4 eluent drops directly on the site leaves the tip, gently rubbing the dropping of the tip portion with another piece of leaves, so pesticide residues in vegetables fully integrated into the surface of the eluent was then dripping droplets on the leaves on a white tablet further testing.
4, sample test:
After the speed test tablet installed and have added a test solution, press < start up > Key, the reaction started the countdown 10 minutes, this time for drug reaction time. [(STRONG) fanying (/ STRONG)] indicator light (Note that the instrument cover during the reaction should remain open, such as closing the cover, the instrument will issue a sounding alarm) ; Close When you hear the instrument issued by rapid beep sound cover, the color automatically starts the countdown three minutes [(STRONG) xianse (/ STRONG)] indicator light; At the end of a color instrument emits a beep to ease again tone, then open the instrument cover, the result of determination.
5 results found
Sample test cards and blank cards compare, white tablet or slightly bluish discoloration results are positive, the same blue as the strongly positive results, indicating a higher pesticide residues, which was light blue weakly positive result, indicating that pesticide relatively low residual amount. white pills into sky blue or with a blank card the same negative result.
Standard color cards (blank card) production: measuring a speed test card in a drop of white pills on pesticide-free eluent, which presents no pesticide can be used as a blue standard color.
(1) This method is biochemical reactions, and therefore should pay particular attention to the impact of some physical and chemical factors on the enzyme activity.
(2) The optimum pH of the reaction is about pH7.5, is biased test sample
It should use an acid or slightly alkaline phosphate buffer extraction process.
(3) White pills and red pills catalytic need to have enough water for the medium, each batch is best to sample along with the sample handling to avoid prolonged evaporated to dryness. Sample volume should be moderate, sample amount is too more liquid spill pollution equipment; sample amount is too small, the water evaporated, the impact of color reaction.
(4) Some samples such as ginger juice, onion, garlic, peppers, tomatoes, wild rice, leeks, papaya, pineapple and tea, spicy ingredients such as rich or allelochemicals, when dealing with this type of sample, the juice should not be allowed too Multi released, should not cut too broken, soaking time not too long, whole sample extraction method can be used if necessary sampling.
(5) can afford to be pesticide-speed measurement card stored in 4-10 ℃ environment would be better, every packet product within three days after opening the best run; if not spent, can be placed equipped with color jar of silica gel moisture absorption agents sealed. If found pesticide-speed measurement card red pills from orange to dark red brown red, indicating that the paper has failed to damp.
Eight, pesticide residue rapid detection instrument maintenance, precautions
1, pesticide residue testing equipment maintenance
(1) a place to store the instrument must be kept dry, clean, no vibration.
(2) within the instrument channel should be kept clean and free of dust, dirt if available cotton was scrubbed as the case more difficult to clean up the dirt, the available cotton was stained with an appropriate amount of alcohol and then wipe clean. ( Prohibit the use of corrosive substances (Such as hydrochloric acid, etc.) Or organic solvents to clean the instrument, in order to avoid damage to the instrument components, causing can not be tested.)
2, pesticide residues detector Cautions
(1) prohibits the instrument DC input via insertion of the companies supporting the other non-power.
Must be read carefully before (2) instrument instrument manual, operate according to the instructions on the procedure, such as an abnormal phenomenon occurs when the instrument shall notify the seller or to the special maintenance repairs.
(3) The user must not disassemble repair, or will be deemed man-made damages, vendors provide after-sales service in accordance with the terms of the instrument.
Nine, pesticide residue fast detector uses a rechargeable lithium battery:
(1) built-in rechargeable lithium battery 7.4V / 1400mAh, fully discharge charging to saturation, time takes about 3 hours at room temperature (20-25 ℃) under the conditions of battery working time is about three hours, can be charged and discharged more than 500 times.
(2) the power adapter into the DC socket, access to the mains 220V / 50Hz, rechargeable lithium battery can be charged for, when switched on the battery charge display power indicator is flashing, when the battery charge to saturation , constant power indicator does not blink, then you can remove the power adapter should first use the built-in rechargeable lithium battery lithium battery is fully charged before use.
(3) Change the power supply (battery / adapter), the should powercycle.
(4) with a rechargeable lithium battery provides power to the instrument, if the instrument screen appears' LO When the character, indicating the current battery is low, should be promptly charged, otherwise the instrument automatically shut down.
After charging the battery, if long-term (one week or more) is not used, the instrument should be used again to re-charge.
(6) An interval of 10 days or so for a rechargeable lithium battery charge and discharge times to extend battery life.
(7) in the indoor or conditional testing, try to use the power adapter.