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Why optical density of bacteri in control is 1 with wavenumber 600?

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The optical density of bacteria in a control sample at a wavelength of 600 nm is often set to 1 to establish a baseline for comparison. Optical density measurements at 600 nm are commonly used to estimate bacterial cell density, but the presence of red fluorescent proteins (RFPs) can lead to inaccuracies in these measurements. To ensure accurate estimation of cell abundance unaffected by fluorescent proteins, measuring optical density at 700 nm is recommended. Additionally, the relationship between optical density and cell titer is influenced by factors like spectrophotometer configuration, light path length, and bacterial cell size, highlighting the importance of calibration for precise comparisons across experiments and instruments. Calibrating optical density to estimated cell count using silica microspheres can provide a standardized and accurate method for relating optical density to actual cell count.

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Open access•Posted Content•DOI Estimating microbial population data from optical density v1 Mats Lundahl 01 Oct 2022	Not addressed in the paper.
Journal Article•DOI Correction for the inherent error in optical density readings. J V Lawrence, S Maier - Show less +1 more 01 Feb 1977-Applied and Environmental Microbiology 54 Citations	The optical density of bacteria in control is 1 at a wavenumber of 600 due to a standard curve correction converting photometric readings to proportional optical density values.
Open access•Journal Article•DOI When Wavelengths Collide: Bias in Cell Abundance Measurements Due to Expressed Fluorescent Proteins. Ariel Hecht, Ariel Hecht, Drew Endy, Marc L. Salit, Marc L. Salit, Matthew S. Munson, Matthew S. Munson - Show less +6 more 06 Jun 2016-ACS Synthetic Biology 29 Citations	The optical density of bacteria in control is 1 at a wavelength of 600 nm due to the bias caused by the absorption of light by red fluorescent proteins.
Open access•Posted Content•DOI When Wavelengths Collide: Bias in Cell Abundance Measurements due to Expressed Fluorescent Proteins Ariel Hecht, Drew Endy, Marc L. Salit, Matthew S. Munson - Show less +3 more 22 Jan 2016-bioRxiv	Not addressed in the paper.

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