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Graphical abstract Highlights • The carbon nanoballs aggregation networks-based aerogels for electrochemical sensing. • The hydrogen peroxide determination in real samples. • Multifunctional electrochemical sensing platform. Abstract In this work, we reported the synthesis of carbon nanoballs aggregation networks-based aerogels (CNANAs) from the biomass waste of shaddock (Citrus maxima) peels for the first time. On the basis of the unique nanostructure of CNANAs with large surface area (446.39 m2 g−1), hierarchical pores (centered at 2, 12 and 87 nm) and high density of edge-plane-like defective sites (EPDSs), the CNANAs as a kind of advanced electrode material exhibited remarkable performance in electrocatalysis. Compared to carbon nanotubes modified glassy carbon electrode (CNTs/GCE) and glassy carbon electrode (GCE), the CNANAs modified GCE (CNANAs/GCE) showed higher electrocatalytic activities towards some important inorganic and organic molecules, such as the probe molecule of potassium ferricyanide, the oxidase-related molecule of hydrogen peroxide (H 2 O 2) and the neurotransmitters of dopamine (DA), ascorbic acid (AA) and uric acid (UA). Based on the superior electrocatalytic activities, the CNANAs/GCE exhibited a wider determination linear range (5–1760 μmol L−1), a higher sensitivity (42.4 μA mmol L−1 cm−2) and a lower detection limit (3.53 μmol L−1) than those at CNTs/GCE and GCE for H 2 O 2 detection. Especially, the CNANAs/GCE also showed great potential for the H 2 O 2 determination in human urine and serum samples. The utilization of environmentally-friendly biomass waste of the shaddock peels as the raw material is a promising way to synthesize low-cost and advanced carbon based electrode material for electrochemical sensors construction. [ABSTRACT FROM AUTHOR]

For the first time, the carbon nanoplates with high density of defective sites derived from the biomass of ground cherry ( Physalis peruviana ) husks was synthesized for the construction of an advanced electrochemical sensing platform. Electrochemical responses of different molecules (potassium ferricyanide, β-nicotinamide adenine dinucleotide, hydrogen peroxide, epinephrine and dopamine, the mixture of four free DNA bases (guanine, thymine, cytosine and adenine), cysteine, ascorbic acid, L-tryptophan, uric acid and acetaminophen) were studied at the biomass derived ground cherry husks derived carbon nanoplates (BG-CNPs) modified glassy carbon (GC) (BG-CNPs/GC) electrode, which shows higher electrocatalytic activities than GC electrode. Especially, the BG-CNPs/GC electrode exhibits remarkably strong electrocatalytic response toward hydrogen peroxide (H 2 O 2 ) compared with carbon nanotubes modified GC (CNTs/GC) and GC electrodes, indicating the great potential feasibility in the detection of H 2 O 2 in human urine as well as the monitoring of H 2 O 2 released from the living cells. All the results indicate that BG-CNPs is a promising carbon material which could be utilized to develop an advanced electrochemical sensing platform with multifunctional applications ranging from voltammetric sensing to amperometric sensing and DNA sensing. [ABSTRACT FROM AUTHOR]

Laboratory experiments were conducted to evaluate effects of Microcystis aeruginosa on population variations, male and resting-eggs production of two Daphnia species, D. carinata and D. pulex. The male and population densities of the two Daphnia dropped with the increase of Microcystis biomass. Population density of the largebodied D. carinata was more strongly restrained by mechanical interference of colonial Microcystis than the small-bodied D. pulex. Male density of the two Daphnia increased quickly at the beginning of the experiment, and then remained at a steady level or declined. There was a positive relationship between population density and density of males for both D. pulex and D. carinata. The presence of Microcystis colonies in the diet was positively associated with the production of ephippia for D. pulex but negatively associated with ephippia production for D. carinata. The percentage of ephippia containing one or two resting eggs was relatively high under lower Microcystis biomass, while the percentage of empty ephippia (containing no resting eggs) was relatively large under higher Microcystis biomass. The results suggest that the production of ephippia and formation of resting eggs were two intricate processes in the different Daphnia species, and that it might be diffi- cult for sexual females to mate with males when the percentage of males was low, consequently leading to the presence of more empty ephippia. It is likely that mechanical interference of colonial Microcystis may accelerate the frequently observed midsummer decline of Daphnia in Microcystis-dominated lakes. [ABSTRACT FROM AUTHOR]