Colorimetric biosensor for phenylalanine detection based on a paper using gold nanoparticles for phenylketonuria diagnosis

l-Phenylalanine-Imprinted Electrochemical Sensor Based on WS2 Nanoflowers on N,B-Doped Graphene and Its Application to Milk Samples

“…The frequency of the measurements can be increased depending on treatment changes and clinical grounds . Up to now, fluorometric enzyme analysis, high-performance liquid chromatography, tandem mass spectrometry, colorimetric assay, gas chromatography–mass spectrometry, and surface-enhanced Raman spectroscopy have been used for detection of the PHEA concentration. − Especially when using methods based on chromatography, too much chemical consumption has significant disadvantages in terms of green chemistry. In addition, these techniques having multistep protocols are complex methods and time-consuming and require expensive equipment and experts.…”

An enzyme cascade fluorescence-based assay for the quantification of phenylalanine in serum

“…2a). 37,38 Serum samples with added Phe of concentrations varying from 0 to 600 μM were incubated with PDH (20 μg ml −1 ), NAD + (1 mM) in glycine-KOH buffer (pH 10.5) for 15 min 90 μL of the resulting mixture were then transferred to the PBS buffer (pH 5.6) containing NTR (1 μg ml −1 ) and RF (10 μM) for 15 min incubation, which was subsequently tested by a microplate reader to record the fluorescence intensity. As the calibration plot of the fluorescence assay depicts in Fig.…”

A highly sensitive colorimetric approach based on tris (bipyridine) Ruthenium (II/III) mediator for the enzymatic detection of phenylalanine

“…To overcome this drawback, a great effort has been made to develop novel transduction processes based on specific reactions with mediators, producing optical or electrical signals. Various electrochemical and colorimetric mediators, including the cationic dye MTT ¥ , which is converted, in the presence of NADH and diaphorase enzyme, to the colored formazan have been reported in previous works of literature ( Jafari et al, 2021 ). Similarly, methoxy phenazine-methosulfate and nitroblue tetrazolium are converted by NADH to colored formazan derivatives ( Robinson et al, 2016 ).…”