Polyphenols photodiode array detectors

Electrochemical detection is sensitive and selective, and it gives useful information about polyphenolic compounds in addition to spectra obtained by photodiode array detectors. Differences in electrochemically active substituents on analogous structures can lead to characteristic differences in their voltammetric behavior. Because the response profile across several cell potentials is representative of the voltammetric properties of a compound, useful qualitative information can be obtained using electrochemical detection (Aaby and others 2004). 

HPLC is designed to separate compounds from complex mixtures based on polarity, solubility, and size properties of each compound. High-pressure liquid chromatography coupled with a photodiode-array detector (HPLC-DAD) provides extensive information on polyphenol stmctures [6, 110]. 

To obtain the identity of a polyphenol, the most common method is to compare the retention time of a particular compound with the standard. The photodiode-array detector DAD can collect UVA isible spectral data as the compounds are... 

In LC-NMR, separation is usually performed on an RP CIS column and broad acetonitrile or methanol gradients are applied, using D2O instead of water, and trifluoracetic acid to improve resolution of polyphenols. UV spectra are recorded for all constituents with the aid of a photodiode array detector. However, it should be taken into consideration that chemical shifts in an RP solvent will slightly differ from those recorded in standard deuterated solvents. 

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