Understanding the interaction of carbon quantum dots with CuO and Cu2O by fluorescence quenching

In spite copper oxide being one of the essential micronutrient, copper oxide in its nano size is found to be toxic in nature; this instigates for the detection of copper oxides in trace levels. In the present study, we demonstrate simple cost effective detection method for CuO/Cu₂O using carbon quantum dots (CQD) by fluorescence quenching technique. CuO/Cu₂O nanoparticles are synthesised by mere variation of fuel ratio by solution combustion technique. The resulting oxides are characterized by various analytical and spectroscopic techniques. Powder X- ray diffraction (PXRD) results reveals that samples prepared with oxidizer to fuel (O/F) ratios 1:1, 1:1.5 and 1:2 showed pure nano CuO, major CuO phase (minor Cu₂O) and major Cu₂O phase (minor CuO) respectively. Further, the samples prepared using 1:1 O/F ratio and calcinated at 700 °C showed highly crystalline CuO phase. In order to study the interaction of CuO/ Cu₂O with CQDs the fluorescence quenching method has been employed. The bimolecular quenching rate constants for the samples prepared with different O/F ratios have been measured. The interaction between CQDs and copper oxides, indicates fluorescence quenching greatly depends on the oxidation state of the copper oxide and can be a promising method for detecting CuO/Cu₂O through CQDs.

Effect of prostaglandin F2alpha on gonadal carbohydrate metabolism of silkworm, Bombyx mori L

Effect of prostaglandin F2alpha (PGF2alpha) on carbohydrate accumulation in gonads of the multivoltine silkworm (hybrid: Xinhang x Keming) has been studied by means of topical application to larvae of the silkworm. Increased weights of larvae and reproduction organs, as well as carbohydrate metabolism in gonads of the silkworm, Bombyx mori L. was found after treatment with prostaglandin F2alpha. The increase in weight (larvae 21.9%, testis 28.9%, and ovary 33.3%) was associated with increases in the biomolecules (20-30%) and LDH and aldolase activity (18-25%). The results suggest that the accumulation of carbohydrates denotes a higher extent of utility of the energy sources in function of the testes and ovaries, and the routine application of prostaglandin F2alpha would be helpful in improving the reproductivity and egg quality of the silkworm.