Colorimeter User Manual

They also maintain electrolyte balance and produce various hormones for a human body or other mammalian body. An artificial kidney, also called a hemodialyzer or dialyzer, and its associated equipment and supplies are designed to replace the blood-purifying functions of the biological kidney. In the center of the artificial kidney design is a semipermeable filter membrane that allows the passage of water, electrolytes and dissolved toxins from the blood to be removed. The membrane retains in the blood, blood cells, plasma proteins and other larger elements of the blood. ⇒ When using a spectrophotometer, it must first be calibrated, which is done using the standard solutions of the known dissolved concentration to be determined in the test solution.

However, the extreme ambient light is blocked from photodiode 250 by the bucket housing. To minimize the reflection of ambient light to the photodiode, the optical devices and housing are opaque and non-reflective to the working wavelength of the LED, such as 660 to 940 nm. This makes it difficult for the lost beams of spectra near where the LEDs come out to penetrate the photodetector.

Smaller buckets can hold 70 microliters, while larger ones can hold 2.5 milliliters or more. The width determines the length of the path of light through the sample, which affects the calculation of the absorption value. Many buckets have a light path of 10 mm (0.39 inches), which simplifies the calculation of the absorption coefficient. Most buckets have two transparent sides facing each other so that light from the spectrophotometer can pass through them, although some tests use reflection, so they only need one transparent side. For fluorescence measurements, two more transparent sides are needed, perpendicular to those used for spectrophotometer light, for excitation light. Some buckets have a glass or plastic lid for use with hazardous solutions or to protect airborne samples.

The length of the route of each vial is the same and the concentration of each of these solutions is the same, but the solutions are of different colors and will therefore be absorbed very differently. The only difference in changing absorption is the Molar Absorptivity constant. For data analysis, the absorption versus concentration graph can indicate how sensitive uv cuvettes the system is when constructing a calibration curve. When using a linear regression equation of the least squares, the slope of the most appropriate line indicates the sensitivity. Sensitivity is the ability to distinguish between small differences in sample concentration. According to Beer-Lambert’s Law, sensitivity can be indicated in part by molar absorption ε.

Some of the LED light instead of being sent through the liquid medium went through the bucket and made its way through the bucket material to the photodiode. In the case of blood, the high Hcts resulted in reflection and scattering with many of the resulting reflected LED lights making their way through the bucket and through the bucket wall into the photodiode. This resulted in erroneous transmission measurements that would lead to false Hcts or measurements of other concentrations of substances and other concentrations of substances.