Quantitative butyrylcholinesterase activity detection by surface-enhanced Raman spectroscopy

The butyrylcholinesterase activity in human blood is an important marker of healthiness. Either level of this enzyme - increased or otherwise - can indicate disease or intoxication. The most popular technique to assess the cholinesterase activity is the detection of thiocholine, a product of enzymatic hydrolysis of butyrylthiocholine. In this work, Ag-paste was used as SERS-substrate and a new technique was created for thiocholine detection. As explained below, the designed technique facilitates also determination of butyrylcholinesterase (BChE) activity both in the buffer and in spike solution with human plasma. Ellman's assay was used as a reference method, a good correlation between spectrophotometric detection and Raman detection was shown.