Navigation Links
UV Absorbance Measurements in SpectraMax Microplate Spectrophotometers MaxLine Application Note #32)

DNA and protein solutions can range between the two extremes. Thus variable meniscus formation can be a source of betweenwell or betweenplate error in microplate analyses, unless steps are taken to ensure that meniscus curvature is identical in all wells. Alternatively, the pathlength may be measured in each well with PathCheck and the absorbance values normalized.


For best precision, the meniscus, whether flat or curved, must be symmetrical, and not skewed up one side of the well (Figure 5B). A sample with an asymmetrical meniscus has a variable and unpredictable optical pathlength. Also an irregular meniscus acts like lens and can deflect the light beam away from the detector, resulting in falsely high absorbance readings.

3 Particulates and bubbles. Dust particles are becoming much more problematic as the beam size and the detector size in the typical instrument become smaller. A particle is not noticeable unless it happens to be in the optical path at the moment of measurement, in which case it has a huge effect. Such particles can cause artifactual spikes in the data up to 0.3 OD above the sample absorbance.

4 Dirty microplates. Microplates can appear perfectly clean, yet have high optical density at wavelengths below 400 nm (the lower limit of detection by the human eye). Fingerprints and residual contamination in reused plates cause errors in UV absorbance measurements.

5 Sample turbidity. Colloidal suspensions scatter light and therefore increase apparent optical density. If the particles are much smaller than the wavelength of the light, the scattering is proportional to (1/lambda)4 and is known as Rayleigh scattering1. Thus the optical density of such a suspension is 10 times greater at 250 nm than at 450 nm. If the particles are larger than the wavelength, light scattering is due to ordinary diffuse reflection (Tyndall scattering).
'"/>

Source:


Page: All 1 2 3 4 5 6

Related biology technology :

1. measuring cell proliferation with SpectraMax M5, M2 and Gemini microplate readers using the CyQUANT Cell Proliferation Assay
2. Fluorometric Protease Assays in the SpectraMax Gemini Microplate Spectrofluorometer: Example Using Caspase3 (MaxLine Application Note #35)
3. LIVE/DEAD Viability/Cytotoxicity Assay for Animal Cells Using the SpectraMax Gemini XS Fluorescence Microplate Reader (MaxLine Application Note #43)
4. Measurement of Green Fluorescent Protein in the SpectraMax Gemini XS Spectrofluorometer (MaxLine Application Note #44)
5. Measurement of Molecular Beacons in the SpectraMax Gemini Spectrofluorometer (MaxLine Application Note #36)
6. Using the NanoOrange protein kit in the Gemini XS, Gemini EM and SpectraMax M2 microplate readers (MaxLine Application Note #22)
7. Using the OligoGreen Oligonucleotide Quantitation Reagent in the Gemini XS, Gemini EM and SpectraMax M2 Microplate Readers (MaxLine Application Note #21)
8. PathCheck Applied to Measurement of Protein Solutions in the SpectraMax Plus Microplate Spectrophotometer (MaxLine Application Note #26)
9. Microdetermination of Phosphorus Using the SpectraMax Plus Microplate Spectrophotometer: Choice of Microplate, Cuvette, or Test Tube Assay Formats (MaxLine Application Note #24)
10. Using the SpectraMax Plus for USP Dissolution Calibration (MaxLine Application Note #27)
11. Verifying Multichannel Pipettor Performance with Standard Dispense Solutions in the SpectraMax Plus (MaxLine Application Note #28)
Post Your Comments:
(Date:7/24/2014)... -- A novel combination of microscopy and data processing ... Ridge National Laboratory an unprecedented look at the surface ... electrochemical properties. , The research team led by ... of a perovskite manganite, a complex material that exhibits ... understand surface behavior could benefit researchers who are interested ...
(Date:7/24/2014)... , July 24, 2014  Asterias Biotherapeutics, Inc. ... emerging field of regenerative medicine, announced today that ... presentation to investors on Tuesday, July 29, 2014, ... presentation will include an overview of Asterias, business ... webcast, visit http://www.ustream.tv/channel/asterias-biotherapeutics at least 15 ...
(Date:7/24/2014)... by group leader Yung-Eun Sung has announced that ... and nitrogen-doped graphenes which can be applied as ... cells. Yung-Eun Sung is both a group leader ... for Basic Science* (IBS) and a professor at ... great significance with regards to the development of ...
(Date:7/24/2014)... most natural and synthetic processes prefer to settle ... or energyit is within the realm of non-equilibrium ... constant changes in energy and phases, such as ... conditions allow humans to regulate their body temperature, ... with seismic activity. , But even though ...
Breaking Biology Technology:ORNL study reveals new characteristics of complex oxide surfaces 2Asterias Biotherapeutics Announces Live Investor Webcast 2Asterias Biotherapeutics Announces Live Investor Webcast 3Asterias Biotherapeutics Announces Live Investor Webcast 4New approach to form non-equilibrium structures 2
... , , , , , ... in eukaryotic cell cultures , requires double-stranded molecules known ... licensed supplier of siRNA, offering a custom , ... directed against common target genes, and a Cancer , ...
... For transfection of eukaryotic cells with RNA and siRNA , , , , , , ... Kit Contents , Storage and Stability ... Technical Assistance , Product Use Limitations ... Safety Information , ...
... QIAshredder spin columns are designed for simple and rapid homogenization , of cell and tissue lysates. ... , , Format: , ... , , Sample source: , ... plant cell or tissue lysates, white blood cell lysates, , ...
Cached Biology Technology:RNAi Gene Silencing System 2RNAi Gene Silencing System 3TransMessenger Transfection Reagent Handbook 2TransMessenger Transfection Reagent Handbook 3TransMessenger Transfection Reagent Handbook 4TransMessenger Transfection Reagent Handbook 5TransMessenger Transfection Reagent Handbook 6TransMessenger Transfection Reagent Handbook 7TransMessenger Transfection Reagent Handbook 8TransMessenger Transfection Reagent Handbook 9TransMessenger Transfection Reagent Handbook 10TransMessenger Transfection Reagent Handbook 11TransMessenger Transfection Reagent Handbook 12TransMessenger Transfection Reagent Handbook 13TransMessenger Transfection Reagent Handbook 14TransMessenger Transfection Reagent Handbook 15TransMessenger Transfection Reagent Handbook 16TransMessenger Transfection Reagent Handbook 17TransMessenger Transfection Reagent Handbook 18TransMessenger Transfection Reagent Handbook 19TransMessenger Transfection Reagent Handbook 20TransMessenger Transfection Reagent Handbook 21TransMessenger Transfection Reagent Handbook 22TransMessenger Transfection Reagent Handbook 23TransMessenger Transfection Reagent Handbook 24TransMessenger Transfection Reagent Handbook 25QIAshredder Homogenizer 2
(Date:7/28/2014)... Roald Amundsen became the first man to reach the ... years later, an international team of scientists led by ... proven that air pollution from industrial activities arrived long ... from widely spaced locations around the Antarctic continent, including ... and precise reconstruction to date of lead pollution over ...
(Date:7/27/2014)... in vitro study has revealed that nicotine and cotinine, ... caused by a certain carcinogen in smoke. , The ... of tobacco leaves and ultimately ends up in the ... lung and liver, where it is activated by a ... in mice has revealed that nicotine can partially interfere ...
(Date:7/27/2014)... that wiped them out if it had taken place ... A fresh study using up-to-date fossil records and improved ... narrative of the prehistoric creatures, demise, some 66 million ... million years before a 10km-wide asteroid struck what is ... extensive volcanic activity, changing sea levels and varying temperatures. ...
Breaking Biology News(10 mins):Industrial lead pollution beat explorers to the South Pole by 22 years and persists today 2Industrial lead pollution beat explorers to the South Pole by 22 years and persists today 3Nicotine found to inhibit DNA-strand break caused by a certain carcinogen in smoke 2Dinosaurs fell victim to perfect storm of events, study shows 2
... to make proteins, key building blocks of all organisms, ... instructions for assembling them. An Iowa State ... marking where these instructions are located in a cell,s ... Journal of Biological Chemistry , Michael Shogren-Knaak, assistant professor ...
... Service scientists have completed a study on a beetle that ... attacked 67 percent of the oak trees in an area ... in the current issue of The Pan-Pacific Entomologist ... so rare it does not even have an accepted common ...
... of Eve to the venomous murder of the mighty Thor, ... of mischief and misery. The worldwide prominence of ... to the serpentbut why, when so few of us have ... Davis, anthropology professor Lynne A. Isbell suggests, lies in the ...
Cached Biology News:New Southern California beetle killing oaks 2
Viral CMV UL146/vCXC1 Biotinylated Affinity Purified PAb...
Cyan Standard is 7-hydroxy-4-trifluoromethylcoumarin...
... small volume applications, including pediatric, neonatal, geriatric, general adult, veterinary and experimental animals. Automatic Calibration with ... ... ... ...
X-Gal, 100 mg. 5-Bromo-4-chloro-3-indolyl-b-d-galactoside.Histochemical substrate for b-galactosidase, used in blue/white screening.Store at -20 C. Protect from moisture. Category: Nucleotides & Enzy...
Biology Products: