How to use the 721 spectrophotometer, it is the kind that has no pointers and no knobs, ask the mast

Model 721 Spectrophotometer 1Check whether the starting position of each adjustment button of the instrument is correct, turn on the power switch, open the dark box cover of the sample chamber, make the meter pointer in the "0" position, preheat for 20min, and then select the monochromatic light wavelength and the corresponding amplification sensitivity file, and adjust the meter to t=0 with the "0" potentiometer. 2.

Cover the sample chamber cover to make the photocell receive light, push the handle of the sample holder, so that the reference solution pool (the solution is loaded into 4 5 heights, set the first grid) in the optical path, adjust the 100 transmittance regulator, so that the meter pointer points to t 100. 3.Repeat the operation of opening the sample chamber cover, adjusting to 0, closing the sample chamber cover, and adjusting the transmittance to 100 until the instrument is stable.

4.Close the lid of the sample chamber and push the handle of the specimen holder to place the sample solution cell on the optical path and read out the absorbance value. The sample chamber lid should be opened immediately after the reading.

5.After measuring, take out the cuvette, wash it and place it upside down on filter paper to dry. Each knob is placed in its original position, the power switch is placed in "off", and the power plug is unplugged.

6.The sensitivity of each level of the amplifier is: "L" 1 times; "2" 10 times; "3" 20 times, the sensitivity increases sequentially.

Because the wavelength of monochromatic light is different, the light energy is different, so different sensitivity levels need to be selected. The selection principle is to use a lower sensitivity setting when the reference solution can be adjusted to t 100 to improve the stability of the instrument. After changing the sensitivity level, "0" and "100" should be re-adjusted.

There should be a digital display without a pointer, just adjust it according to what was said upstairs.

Categories: Healthcare.

Analysis: 1) 721-Spectrophotometer.

1.Turn on the power supply, turn on the instrument switch, lift the lid of the dark box in the sample chamber, and warm up for 10 minutes.

2.Set the sensitivity switch to "1" (if the zero adjuster cannot be set to "0", you need to use a higher setting.) ）

3.Turn the wavelength selector according to the desired wavelength.

4.Pour the blank solution and the measurement solution into the cuvette 3 4 respectively, wipe the outer wall with mirror polishing paper, put them in the sample chamber, and align the blank tube with the optical path.

5.Adjust the zero regulator with the camera obscura lid open so that the readingdial pointer points to t=0.

6.Close the lid of the camera obscura, adjust the "100" regulator, make the t=100 of the blank tube, gradually pull out the sample slide rod after the pointer is stable, read out the optical density value of the measuring tube respectively, and record.

7.After the color comparison is completed, turn off the power, take out the cuvette and wash it, and wipe the sample chamber with a soft cloth or soft paper.

Principles: (1) Lamber-Beale law.

Light is an electromagnetic wave that has a certain wavelength and frequency. The wavelength range of visible light is 400 760 nm, ultraviolet light is 200 400 nm, and infrared light is 760 500000 nm. Visible light exhibits different colors due to different wavelengths, and these wavelengths present different colors within a certain range of light called monochromatic light.

The white light emitted by the sun or tungsten filament, etc., is composite light, which is a mixture of various monochromatic lights. Using a prism, white light can be divided into various monochromatic lights arranged in wavelength order, i.e., red, orange, yellow, green, cyan, blue, violet, etc., which is the spectrum. Colored substance solutions can selectively absorb a part of the energy of visible light and appear different colors, while some colorless substances can characteristically choose the energy of ultraviolet or infrared light.

Substances absorb some wavelengths of light emitted by the light source to form an absorption spectrum, because the molecular structure of the substance is different, the absorption capacity of light is different, so each substance has a specific absorption spectrum, and under certain conditions its absorption degree is proportional to the concentration of the substance, spectrophotometry is the use of this absorption characteristics of the substance to carry out qualitative or quantitative analysis of different substances.

In colorimetric analysis, the depth of color of the colored solution is determined by the intensity of the incident light, the concentration of the colored solution, and the thickness of the liquid layer. When a beam of monochromatic light irradiates a solution, the stronger the incident light intensity, the greater the concentration of the solution, the thicker the thickness of the liquid layer, and the more light is absorbed by the solution. This is the theoretical basis for spectrophotometry for the quantitative analysis of substances.

How to zero the 721g spectrophotometer1 Before using the instrument, the user should first understand the structure and working principle of the instrument, as well as the function of each operation knob. Before the power is turned on, the instrument should be checked, the power cord should be firmly wired, the ground should be good, the starting position of each adjustment knob should be correct, and then the power switch should be turned on. 2 Turn on the power, the indicator light is on, the selector switch is set to "T", and the wavelength is adjusted to the wavelength for testing.

The instrument is warmed up for 30 minutes. 3. Open the sample chamber cover, adjust the "0" knob, make the number display "Cover the sample chamber cover, put the cuvette rack in the distilled water correction position, make the photocell receive light, adjust the transmittance "100" knob, make the number display "After preheating, press (3) to adjust "0" and "100" several times in a row, and the instrument can laugh and punch for the measurement work. 5 Measurement of absorbance:

Press (3) to adjust the "and" and "100" of the instrument, put the selection switch to "A", adjust the absorbance to zero knob, and make the number of Yousheng regret displayed as "."000", and then move the measured sample into the optical path, and the displayed value is the absorbance value of the measured sample.

Model 721 Visible Spectrophotometer Operating Procedures.

1.Before turning on the instrument switch, make sure that the instrument sample chamber is in the first slot. There is something in the optical path that will affect the self-test of the instrument and even cause the instrument to malfunction.

2.Turn on the instrument switch and preheat the instrument for 20 minutes. After the instrument is connected to the power supply, it will enter the self-test state, and the instrument will automatically stop in the absorbance test mode at the end of the self-test.

3.Use the wavelength setting knob to set the wavelength at the position of the analysis wavelength that will be used. 4.

Press the mode setting button to select transmittance method t. Make the sample chamber of the instrument in the first slot and press the button to adjust the transmittance to zero. The display displays.

5.Make the sample chamber of the instrument in the first slot and press the 100% key to adjust the 100% transmittance. The display shows BLA, wait a while, when the adjustment is complete, the display shows 6

Press the mode setting button (mode) to select the absorbance (a) method, and the display will display 7Pour the reference solution and the tested solution into the cuvette, respectively. Open the sample chamber lid and insert the cuvettes containing the solution into the cuvette slot separately and close the sample chamber lid.

8.The solution to be measured is pushed or pulled into the optical path, and the absorbance parameters of the sample to be measured are displayed on the display.

9.Note: In general, the reference sample is placed in slot 1 of the sample chamber, and the transmittance of the cuvette used by the instrument is tested and matched.

Unmatched cuvettes will affect the accuracy of the sample test. There should be no fingerprints and solution traces on the surface of the translucent part of the cuvette, and the height of the internal solution surface should not be less than 25 mm, and there should be no bubbles and suspended solids, otherwise the accuracy of the test parameters will be affected.

Xinxiang Medical College Sanquan College - 722 spectrophotometer use.

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1.After adjusting the wavelength you want to test, turn on the power, open the cover, and warm up for 15-20 minutes.

2.After preheating, pour the blank, standard, and measurement solution into the cuvette 2 3 respectively, and put them into the colorimetric slot frame in turn, open the lid to zero with a blank tube, then cover the lid and adjust 100, repeat the zero and 100 steps 2-3 times, after stabilization, pull out the colorimetric lever to read out and record the standard A value, and then pull a liver to read out and record the A value of the measurement solution. Can.

Pay attention to the clicker when pulling the rod, and make sure that the cuvette is heard to accurately enter the optical axis. The negative side can cause inaccuracies in the test.

When you buy the instrument, the manufacturer is trained!