It must, of course!: - Because Lambdamax in a Wavelength-Range is defined this way!
Absorbance maximum
to ensure maximum absorbance of light by the solution
454 nm
520nm
If you have a spectrofotometer ( the thing to mesure the absorbance) then play with the setting and use a maximum. this will lay close to your specific absorbance or take the pharmacopea or a MERCK index
villi are present to increase the surface area of cell for maximum absorbance of nutrients
1.7 - 2.0 -- for "pure" DNA Reference: http://www.bmglabtech.com/application-notes/absorbance/absorbance-dna-quantitation-168.cfm
using uv-visible spectrophotometer concentration vs absorbance is plotted and the maximum absorbance of the drug is lambda max of the drug. then after it will decrease. still if needed clarification, refer beer lambert"s law
"absorbance"Since in the experiment, you probably choose the wavelength, then measure the absorbance (absorption?, the absorbance is the dependent variable.
Maximum effective range at a point target: 550 metres Maximum effective range at an area target: 800 metres Maximum range: 3600 metres
Short answer:Using the maximum wavelength gives us the best results. This is because at the peak absorbance, the absobance strength of light will be at the highest and rate of change in absorbance with wavelength will be the smallest. Measurements made at the peak absorbance will have the smallest error.Long answer: It really depends on what is the largest source of error. Taking the readings at the peak maximum is best at low absorbance, because it gives the best signal-to-noise ratio, which improves the precision of measurement. If the dominant source of noise is photon noise, the precision of absorbance measurement is theoretically best when the absorbance is near 1.0. So if the peak absorbance is below 1.0, then using the peak wavelength is best, but if the peak absorbance is well above 1.0, you might be better off using another wavelength where the absorbance is closer to 1. Another issue is calibration curve non-linearity, which can result in curve-fitting errors. The non-linearity caused by polychromatic light is minimized if you take readings at either a peak maximum or a minimum, because the absorbance change with wavelength is the smallest at those wavelengths. On the other hand, using the maximum increases the calibration curve non-linearity caused by stray light. Very high absorbances cause two problems: the precision of measurement is poor because the transmitted intensity is so low, and the calibration curve linearity is poor due to stray light. The effect of stray light can be reduced by taking the readings at awavelength where the absorbance is lower or by using a non-linear calibration curve fitting technique. Finally, if spectral interferences are a problem, the best measurement wavelength may be the one that minimizes the relative contribution of spectral interferences (which may or may not be the peak maximum). In any case, don't forget: whatever wavelength you use, you have to use the exact same wavelength for all the standards and samples. See http://terpconnect.umd.edu/~toh/models/BeersLaw.htmlTom O'HaverProfessor Emeritus