Food Process Machine,Food Making Machine,Food Mixer Machine,Power Mixer Guangzhou New Power Catering Equipment Manufacturing Co.,Ltd , https://www.gznewpower.com
The photoelectric conversion device is used to detect the change of light transmittance during the titration process (see Fig. 1); according to the voltage change curve, the instrument control system automatically records, samples, and determines the titration end point; according to the standard reducing sugar amount consumed when the titration end point is reached, The control system automatically calculates the reducing sugar content in the sample and displays and prints the results. The electrical signal change and control principle of the titration process (see Figure 2) are as follows:
Reducing Sugar Analyzer User Manual
SGD-IV type
Automatic reducing sugar meter
user's Guide
Institute of Biology, Shandong Academy of Sciences
Shandong Provincial Key Laboratory of Biosensors
First, the basic principle
The automatic reducing sugar meter (SGD-IV type) is designed according to the principle of Feilin reagent measurement, and its principle is consistent with the current national standard; Feilin reagent is an oxidant composed of A and B liquids. A certain amount of methyl ethyl ether is mixed during the measurement, first forming copper hydroxide, and then forming a potassium potassium tartrate complex. Methylene blue is used as a titration end point indicator and is blue in the oxidizing solution and is colorless after being reduced. With the standard reducing sugar titration, the reducing sugar firstly reduces the copper until the copper is reduced, so that the methine blue is reduced to colorless, which is the end point of the titration.
During the titration, the color of the solution gradually changes: blue → dark blue → light blue → purple red → pale purple → suddenly changes to colorless and transparent at the end point.
Figure 1 titration voltage curve
Figure 2 Control schematic diagram of automatic reducing sugar meter
Second, the instrument structure
The instrument consists of a reaction system, an automatic control system and a casing.
1 , the reaction system
The core component is the reaction cell, and its cross-sectional structure is shown in Figure 3.
Figure 3 Structure diagram of the reaction cell of the automatic reducing sugar meter
The reaction system is composed of the main body of the titration cell; the incident light source and the photoelectric converter are arranged on the left and right sides of the titration cell, and the liquid inlet and outlet pipes are arranged on the front and rear sides of the titration cell, and the temperature sensor and the liquid heating electrode are inside the titration cell, and the liquid temperature is adjusted as needed; the titration cell There is a magnetic stirrer at the bottom to make the titration liquid evenly mixed; the upper part is the inlet, and the sample to be tested can be injected into the titration cell with a pipette.
2 , automatic control system
Including power circuit, control circuit, control panel, micro-printer; according to the setting program to control the flow of the titration pool liquid, liquid temperature, agitation, photoelectric reaction information collection and conversion, calculation, measurement results display and printing. The syringe pump automatically adds standard solution, titrant, and two peristaltic pumps to automatically perform cleaning and emptying. The automatic reducing sugar meter pump system is shown in Figure 4.
Figure 4: Structure diagram of the automatic reducing sugar meter pump system
Pump tube connection:
(1) The right port of the cleaning pump is connected to the silicone tube to the distilled water bottle (the connecting silicone tube should be placed in distilled water), and the left port is connected with the silicone tube to the uppermost stainless steel pipe of the reaction tank (which is connected at the factory).
(2) Drain the left port of the pump to connect the silicone tube to the waste bottle (the silicone tube should be placed in the self-contained waste water bottle), and the right port is connected to the silicone tube to connect the bottom stainless steel pipe of the reaction tank (it is connected at the factory) ).
(3) Reagent pump A and B liquid injector ports are connected to the corresponding solenoid valve No. 2 port to connect the silicone tube (which has been connected at the factory), and the solenoid valve No. 1 port is connected with the silicone tube to the corresponding A and B liquid reagent bottles (required separately) Place the connected silicone tube in the A and B liquids according to the instructions. The solenoid valve No. 3 is connected to the silicone tube to the A and B liquid stainless steel pipes of the reaction cell (connected at the factory).
(4) Titration pump port is connected to solenoid valve No. 2 port to connect silicone tube, solenoid valve No. 1 port is connected with silicone tube to titration sugar bottle (this connection silicone tube should be placed in 0.7% titration sugar solution according to the specification), electromagnetic Valve No. 3 is connected to the silicone tube and connected to the reaction tank to titrate the sugar stainless steel pipe (which is connected at the factory).
Third, reagent preparation
1 , the reagent name:
(1) Copper sulfate (CuSO 4 • 5H 2 O)
(2) sodium hydroxide (NaOH)
(3) Sodium potassium tartrate (C 4 H 4 O 6 KNa•4H 2 O)
(4) Potassium ferrocyanide (K 4 F 4 (CN) 6 • 3H 2 O)
(5) Anhydrous glucose (C 6 H 12 O 6 )
(6) methine blue (C 16 H 18 CIN 3 S•3H2O)
(7) distilled water
(8) Hydrochloric acid
2 , reagent preparation
Drying with anhydrous glucose (C 6 H 12 O 6 ): drying at 103 ° C for 3 hours, and then storing in a desiccator at room temperature for later use.
3 , reagent preparation:
(1) methine blue liquid (1.0%):
Accurately weigh 10.0 g of methylene blue, dilute the distilled water to a volume of 1000 mL, and place in a brown bottle for use.
(2) 1.00% glucose solution (calibrated sugar), ie 10.00 g / liter of glucose solution:
Accurately weigh 10.000g of anhydrous glucose, dissolve it in distilled water, add 5mL of hydrochloric acid, dilute to 1000mL, and put it in the refrigerator for use.
(3) Titration of sugar solution (0.7%):
Accurately weighed 7.0g of anhydrous glucose, dissolved in distilled water, added 5.0mL of hydrochloric acid, and dilute to 1000mL, and put it in the refrigerator for use.
(4) Liquid A:
Accurately weigh 11.74 g of copper sulfate (CuSO 4 • 5H 2 O), dissolve and add 7.0 mL of methine blue solution (1.0%) to a volume of 1000 mL.
(5) Liquid B:
Accurately weigh 4.70g potassium ferrocyanide (K 4 F 4 (CN) 6 •3H 2 O), 63.20g sodium hydroxide (NaOH), 58.50g sodium potassium tartrate (C 4 H 4 O 6 KNa•4H 2 O) After solubilization, the volume is adjusted to 1000 mL.
(6) When measuring special samples, according to the concentration range of the liquid to be tested, the concentration of the Flint A and B liquids determined by our technicians can be selected.
Fourth, the panel
The control panel is shown in Figure 4:
Figure 5 Schematic diagram of the control panel of the automatic reducing sugar meter
Mode key:
In the standby mode, press the [Scale] key to calibrate T2 .
Function key:
After powering on (power on), each time you press the [Function] key, the screen displays the following setting parameters:
“Drain†: Empty the pump (1) (default is 11 seconds) and set the pumping time for the drain.
“Cleaning†: Clean the pump (2) (default is 6 seconds) and set the cleaning pump rotation time.
“Reagent†: Reagent pump (3) (default is 11 seconds), set the reagent pump rotation time, that is, control the Ferin reagent injection amount.
“Reset 1†: Reagent pump reset time (default is 19 seconds).
“Reset 2†: titration pump reset time (default is 19 seconds).
“Difference†: The sampling voltage is selected according to different samples (default is 3).
"Number of times" : The number of consecutive measurements (the default is 10 times).
The above parameters can meet the needs of special users. For example, if you set an item, enter the value (**.0) in the display state and press the enter key to complete the setting, but repeat the same every time you turn it on. Settings. Normal users do not need to set.
Print button: Press the button once to cancel the print function, and press again to resume the print function.
Cleaning button: When titration (reaction) is in progress, press this button to terminate the current reaction, enter the emptying cleaning, and automatically enter the next measurement after completion.
Reset 1: Press this button and the reagent pump automatically discharges air bubbles from the injection line. If the air bubble is not completed at one time, press the button again until there are no air bubbles in the pipe. ( Note: When using it for the first time, it is necessary to operate several times in succession due to the large number of bubbles in the pipeline. )
Reset 2: When this button is pressed, the titration pump automatically discharges the bubbles in the titrated sugar line. If the air bubble is not completed at one time, press the button again until there are no air bubbles in the pipe.
( Note: When using it for the first time, it is necessary to operate several times in succession due to the large number of bubbles in the pipeline .)
 Measurement button: When the titration reaction is in progress, when the number on the liquid crystal display changes, press this button. After the measurement is completed, it will automatically enter the standby state. Press this button again to start the next measurement. In the standby state, press this button to automatically measure the set number of times, the default is 10 times ( "number" setting item).
Start button: After the instrument is powered on, press the [Start] key to enter the complete measurement procedure (blank, calibration, measurement).
Numeric symbol key: Digital input for parameter setting.
Decimal point key: Used to enter the decimal point when parameter setting.
Five, the operation steps
1. Turn on the power and turn on the power switch on the lower right side of the rear of the instrument to enter the standby state.
2. Press the [Start] key to run the instrument. Automatically enters the stability program and the calibration values ​​T1 (blank), T2 (standard), and completes a set of measurements according to the number of memory settings (default is 10).
3. If the special setting needs to adjust the parameter setting, press the [Function] key repeatedly after pressing the [Start] key after turning on the power switch to set the parameter values ​​(if no parameter value is input, each parameter value is the instrument's value). Initial default value), press the [Input] key to complete the parameter setting. Generally, there is no need to reset the parameters, this step is skipped.
4. After the instrument printer prints the T1 value, the T2 value should be manually calibrated. When the LCD screen displays “calibrated injection†, use a pipette to draw 500 μl of standard glucose (1.00% or 10.000 g/L) solution into the reaction cell for calibration. After the reaction is completed, the instrument will automatically print out. The value is T2.
5. After the T1 and T2 values ​​are scaled, the instrument automatically enters the measurement procedure. When the LCD screen displays “sample injection†, 500 μl of the sample to be tested is pipetted into the reaction cell, and the instrument automatically completes the measurement of the sample, and calculates and prints the measurement result.
6. A set of samples (the number of measurements is set according to the “number of timesâ€, and the default value is 10 times without setting the instrument.) After the measurement is completed, the instrument enters the standby state. To continue the measurement, directly press the [Measure] key to enter the measurement cycle of the next set number of times (if not set, the instrument defaults to 10 times).
Special note: If you need to pause during the measurement process, press the [Measure] button during the titration (when the LCD time is digitally pulsating), after the measurement is completed, it will stop automatically; just press the [Measure] button again. , can continue this round of determination, no need to re-calibrate.
7. Turn off the power switch in standby mode to shut down.
8, special operating instructions:
(1) During the titration process (when the display time is digitally pulsating), press the [Cleaning] button to end the measurement. The instrument does not print the measurement result and repeats the operation automatically.
(2) Recalibrate the T2 value. In the standby state after the completion of a set of measurement cycles of the instrument, press the [Scale] key, and according to the LCD display “Scheduled injection†prompt, inject 500 μl of standard glucose for calibration (1.00% or 10.00 g/ Lit) solution, the instrument automatically completes the calibration and reprints the T2 value. Press the [Measure] key again to complete the next set of measurements according to the recalibrated T2 value.
(3) Recalibrate the T1 value. The T1 value cannot be scaled separately. If it is necessary to rescale the T1 value, in the standby state, press the [Start] key to complete the T1 and T2 value calibration and enter the routine measurement procedure.
Six, matters needing attention
1. The instrument uses a regulated power supply.
2. After the instrument is used for two weeks, the reaction cell should be cleaned, soaked in the cleaning solution for two minutes, and then discharged with a syringe.
3. Beware of splashing of the reaction solution.
4. Do not rotate the left and right ears of the reaction cell after the reaction cell is installed. Be careful not to leak liquid.
5. Use the pipette correctly.
6. When the instrument is not used for a long time, remove the reagents in the pipeline and inject distilled water.
Seven, common problems and treatment measures
problem appear
Check item
Treatment
No response at boot
Check the power cord,
Fuse
Connect the power cord,
Keep the fuses intact.
The reaction tank is heated continuously
Check temperature controller, right ear of reaction cell, stirring rotor
Connect the temperature controller plug and the right ear of the reaction cell
Reaction time is displayed as 99 seconds
Check whether the liquid in the liquid, the syringe, the connecting pipe, the stirring rotor, the heating temperature, and the brightness of the LED are normal, and observe whether the titration is to the end point.
Keep the liquid level of the reagent bottle, no bubbles or damage in the syringe and the pipe, and adjust the reagent concentration appropriately.
Measured value drift
Check the syringe, connecting the pipe, stirring the rotor, the light source, the solenoid valve, the heating temperature, and the inlet and outlet of the reaction tank are blocked.
Keep the syringe and connecting pipe free from air bubbles and damage, stir the rotor, and the light source works normally. Replace the solenoid valve
Import and export
The printer does not take paper
Check printer, printing paper
Replace the printing paper
In case of other problems, please contact our technical staff.
Attached:
Installation list:
1 reducing sugar meter
2 micro sampler one
3 Instructions for use