[mohanrnd]

What is procedure for calibration of uv?

[at_banait]

How calibrate uv-vis spectrophotometer

[sveegaard]

1) Reset the UV spectrophotometer at the desired wavelength with a blank sample (pure solvent, no analyte and same test procedure as the other samples)
2) Make 5-10 standard solutions of your analyte
3) The linear area of absorbance vs. concentration of standard solution obeys Lambert-Beer's law and is the usable area of detection

[sveegaard]

1) Reset the UV spectrophotometer at the desired wavelength with a blank sample (pure solvent, no analyte and same test procedure as the other samples)
2) Make 5-10 standard solutions of your analyte
3) The linear area of absorbance vs. concentration of standard solution obeys Lambert-Beer's law and is the usable area of detection

[passionbiotech]

Spectrophotometer Calibration

A spectrophotometer can be found in many research, biology, chemistry, and industrial laboratories. Spectrophotometers are used for research and data analysis in various scientific fields. Some of the main fields in which a spectrophotometer is used is physics, molecular biology, chemistry, and biochemistry labs. Typically, the name refers to Ultraviolet-Visible (UV-Vis) Spectroscopy.

What a spectrophotometer does is transmit and receive light. The spectrophotometer is used to analyze samples of test material by passing light through the sample and reading the intensity of the wavelengths. Various samples change the light in many different way and this allows researchers to acquire more information about the test material, by viewing the change in light behavior as it passes through the sample. These results must be accurate or the researcher will just be wasting time using a flawed instrument. The only way to ensure accuracy is to by performing a spectrophotometer calibration.

What Is Spectrophotometer Calibration?

Spectrophotometer calibration is a process in which a researcher or scientist uses a calibration standard to test the accuracy of the light source. This procedure is critical to ensure that the spectrophotometer is working properly and the measurements are correct. The calibration procedure varies slightly for different instruments. Most major manufacturers provide a detailed calibration guide in the owner's manual so that researchers know how to calibrate the equipment properly. Keeping a calibration log is also important to show when and who performed the last calibration.

Tools Used to Calibrate Spectrophotometer

Spectrophotometer calibration filters a.k.a neutral density filters are primarily used to calibrate various transmittance values and are derived from NIST (National Institute of Standards and Technology). Some of NIST's standards include SRM 2031, 2034, NIST930e, etc.).

Some spectrophotometer manufacturers recommend researchers to send the machine in to be calibrated. The problem with sending the machine in is the cost research time, shipping costs, and other various outside influences. It is best and most convenient to calibrate the spectrophotometer without sending it out of the lab.

Using Neutral Density Filters To Calibrate a SpectrophotometerFor decades liquid calibration standards have been used. Starting in 2010, solid state filters started replacing the liquid filters due to their ability of never having to be re-calibrated or replaced. Solid neutral density filters are also easy to handle and will not break if they are accidentally dropped or mishandled.

The solid state spectrophotometer calibration neutral density filters can test for photometric accuracy as well as stray light. To ensure 100% accuracy, testing is done at a minimum of five test points. These spectrophotometer calibration filters can be used to calibrate machines made by Thermo Scientific, Beckman Coulter, Hitachi, Perkin Elmer, Hewlett Packard, Agilent, Shimadzu? Passion and more.

How to Calibrate Using Neutral Density Filters

In spectrophotometer calibration, a reference is used to zero out the instrument. When using neutral density filters no special filters are required to zero out the instrument. To calibrate the device simply place the neutral density filter inside the spectrophotometer, zero out the settings, and run the instrument. The results must be compared to a calibration certificate that is supplied by the manufacturer of the calibration standards. If the results are within the tolerance range specified by the manufacturer, then the spectrophotometer is properly calibrated.

Before calibrating a spectrophotometer and to ensure proper readings, it must be allowed to warm up before use. Most models take about 10 minutes or so to warm up. Spectrophotometer calibration must not be done while the machines is warming up. If someone tries to calibrate spectrophotometer during the warmup phase it will throw the settings off.

More information about cuvette manufacturing and spectrophotometers can be found at PrecisionCells.com

Simcha Dov is a certified calibration specialist and has assisted in the designing and manufacturing of modern day neutral density filters.

For all your Science Equipment needs Contact http://www.passionbiotech.com/