Direct Turbidity Measurement Using Photopette®
Determining Turbidity of an aqueous solution is a frequently used procedure to estimate the quality of water, or even concentration of suspended particles such as cells, bacteria, and mud.
Turbidity can be defined as a decreased in the transparency of a solution due to the presence of suspended and some dissolved substances, which causes incident light to be scattered, reflected and attenuated rather than transmitted in straight lines; the higher the intensity of the scattered or attenuated light, the higher the value of turbidity .
Nephelometric turbidity units (NTU) are often used to express turbidity. NTU can be defined as the intensity of light at a specified wavelength scattered or attenuated by suspended particles or absorbed at a method-specific angle (90 degrees), from the path of the incident light compared to a synthetic chemically prepared standard .
Following the USEPA method and ISO 7027 method, the turbidity is measured at wavelengths of 570 nm and 850 nm respectively. This application note highlights the measurements of OD at these two wavelengths using the Photopette®.
Determination of Lactate Concentration Using Photopette® Cell
This application note provides an easy and fast enzymatic assay to quantify lactate in biological samples such as serum, plasma, urine, cell culture/fermentation media or in food & beverage products using Photopette®.
During anaerobic glycolysis, energy is produced. In this process, lactate dehydrogenase (LDH) catalyses the oxidation of lactate to pyruvate and an equimolar amount of nicotinamide adenine dinucleotide (NAD+) is reduced to its reduced form NADH. The amount of NADH produced is directly proportional to the lactate concentration in the sample . The produced NADH is measured by its absorbance at 340 nm.
Determination of Ethanol In Alcoholic Beverages Using Photopette® Cell
The objective of this application note is to demonstrate how Photopette® Cell can be used to quantify the amount of ethanol in beverages on the example of wine.
Hela Cell Counting by Optical Density Measurements with Photopette®
This application note is to demonstrate how Photopette® can be used for measurement of cell number by optical density. Advantageously, Photopette® enables cell number measurements directly in the cell culture hood. This application note demonstrated cell number measurements of HeLa cell lines, how to prepare a calibration curve and to determine the biomass in the cell suspension. Furthermore, it acts as a handy guide to get you started with Photopette®, and outlines application-specific parameters for reference.
Measuring Cell-Viability by Resazurin (Alamarblue) Assay using Photopette® Cell
This application note is to demonstrate how Photopette Cell can be used to measure cell-viability of eukaryotic cells using a Resazurin Assay. Furthermore, it acts as a handy guide to get you started with Photopette Cell, and outlines application-specific parameters for reference.
Protein Measurement using Bradford Assay and Photopette®
This application note is to demonstrate how Photopette® can be used for measurement of an unknown protein sample using a standard Bradford assay kit. Furthermore, it acts as a handy guide to get you started with Photopette® and outlines application-specific parameters for reference.
Measuring Protein Concentration Directly using Photopette® Bio
This application note is to demonstrate how the Photopette® Bio device can directly measure protein concentrations in an unknown sample. Furthermore, it acts as a handy guide to get you started with Photopette® Bio and outlines application-specific parameters for reference.