Author/Authors :
ELLINA AZMI, NUR Pusat Penyelidikan Bioteknologi Perindustrian, Malaysia , ABDULLAH, JAAFAR Pusat Penyelidikan Bioteknologi Perindustrian, Malaysia , AHMAD, MUSA Universiti Kebangsaan Malaysia - Fakulti Sains dan Teknologi - Pusat Pengajian Sains Kimia dan Teknologi Makanan, Malaysia , YOOK HENG, LEE Universiti Kebangsaan Malaysia - Fakulti Sains dan Teknologi - Pusat Pengajian Sains Kimia dan Teknologi Makanan, Malaysia , SIDEK, HAMIDAH Pusat Penyelidikan Bioteknologi Perindustrian, Malaysia , SAMSULIDA, ABD RAHMAN Pusat Penyelidikan Bioteknologi Perindustrian, Malaysia
Abstract :
Bioanalysis for ammonium detection based on dual enzyme system Glutamate dehydrogenase/ Diaphorase (GLDH-Dph) and thiazolyl blue tetrazolium bromide (MTT) reagent has been described. In this work, GLDH will catalyze the conversion of α-ketoglutaric acid to L-glutamate and β-nicotinamide adenine dinucleotide (NADH) will be oxidized to NAD+ in the presence of ammonium. The excess of unreacted NADH was then oxidized to NAD+ by Dph and MTT reagent was reduced to purple color formazan. The intensity of formazan product formed was observed at the wavelength of 563 nm by using spectrophotometer. Bioanalysis showed optimum response for ammonium detection at phosphate buffer of pH 8, GLDH, Dph and MTT concentrations at 13.2 unit/mL, 1.17 unit/mL and 0.2 mM, respectively. Bioanalysis showed linear response towards ammonium in the concentration range of 3 - 50 μM with the detection limit of 1 μM.
Keywords :
Ammonium , bioanalysis , Dph , GLDH
