RESUMO
To determine urea accurately in clinical samples, food samples, dairy products, and agricultural samples, a new analytical method is required, and non-enzymatic methods are preferred due to their low cost and ease of use. In this study, bitter gourd peel biomass waste is utilized to modify and structurally transform nickel oxide (NiO) nanostructures during the low-temperature aqueous chemical growth method. As a result of the high concentration of phytochemicals, the surface was highly sensitive to urea oxidation under alkaline conditions of 0.1 M NaOH. We investigated the structure and shape of NiO nanostructures using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). In spite of their flake-like morphology and excellent crystal quality, NiO nanostructures exhibited cubic phases. An investigation of the effects of bitter gourd juice demonstrated that a large volume of juice produced thin flakes measuring 100 to 200 nanometers in diameter. We are able to detect urea concentrations between 1-9 mM with a detection limit of 0.02 mM using our urea sensor. Additionally, the stability, reproducibility, repeatability, and selectivity of the sensor were examined. A variety of real samples, including milk, blood, urine, wheat flour, and curd, were used to test the non-enzymatic urea sensors. These real samples demonstrated the potential of the electrode device for measuring urea in a routine manner. It is noteworthy that bitter gourd contains phytochemicals that are capable of altering surfaces and activating catalytic reactions. In this way, new materials can be developed for a wide range of applications, including biomedicine, energy production, and environmental protection.
RESUMO
Manchar Lake is the largest natural freshwater lake in Pakistan. The Lake has received less fresh water in past few years. In addition, drainage water is being discharged in the Lake through Main Nara Valley Drain (MNVD) since many years. Consequently, concern has grown regarding the water quality of the Lake. The aim of this study was to assess the water quality of Manchar Lake and MNVD and the objectives were to determine physiochemical properties and the concentrations of common cations and anions as well as seven trace metals i.e. Cu, Ni, Zn, Co, Fe, Pb and Cd. The concentration of the trace metals were determined by simultaneous preconcentration and solvent extraction using flame atomic absorption spectrometer. Results of physicochemical parameters of Manchar Lake water samples showed mean pH 8.4 (+/-0.2), conductivity 2,310.3 (+/-581.3) muS cm(-1) and hardness (as CaCO3) 213.1 (+/-62.3) mg l(-1). Mean concentrations of cations and anions were Na 521.5 (+/-49.7), Cl(-) 413.6 (+/-225.7), Ca 70.7 (+/-12.9), Mg 56.2 (+/-28.9), K 17.6 (+/-6.5), NO(3-) 0.34 (+/-0.2) and PO4(3-) 0.02 (+/-0.01) mg l(-1). Mean concentrations of trace metals were Zn 15.7 (+/-1), Fe 12 (+/-3.5), Pb 9 (+/-2.7), Cu 8.9 (+/-7.7), Ni 4.3 (+/-3.4), Co 4 (+/-3.4) and Cd 1.1 (+/-1) microg l(-1). MNVD water samples showed mean pH 8.9 (+/-0.8), conductivity 1,735.7 (+/-567.8) muS cm(-1) and hardness (as CaCO3) 184.8 (+/-32.4) mg l(-1). In MNWD, the mean concentrations of cations and anions were Na 482.7 (+/-11.7), Cl(-) 395.7 (+/-271.5), Ca 79.1 (+/-23.5), Mg 54.2 (+/-28.1), K 26.2 (+/-21.3), NO(-3) 0.5 (+/-0.3) and PO4(3-) 0.1 (+/-0.1) mg l(-1). Mean concentrations of trace metals observed in MNWD water were Fe 14.9(+/-3.5), Cd 8.3 (+/-9.4), Pb 6.9 (+/-2.4), Cu 6.6 (+/-3.1), Zn 6.2 (+/-1.8), Co 4.5 (+/-2.7), and Ni 3.5 (+/-2.9) microg l(-1). The pH of both Manchar Lake and MNVD waters and concentration of Pb in Manchar Lake and concentration of Cd in MNVD water were higher than the World Health Organisation's guideline values for the drinking water quality. The water quality of Manchar Lake was found degraded.
