Konstantin Paliienko

Aggregate behaviour of carbon dots (CDs) in aqueous solutions in the presence of various metal ions was studied by means of dynamic light scattering (DLS).

Effortless and low-cost transformation of bulk germanium into nanoparticles using an ordinary kitchen blender (image created with AI).

An experimental study of the state of regulation of spontaneous and neurotransmitter-induced motility of the gastrointestinal tract and the hepatobiliary system under the action of gadolinium-based contrast agents is presented.

Carbon dots synthesized from peanut shell biomass and doped with gadolinium exhibit significant potential as efficient MRI contrast agents.

Xenobiotic and trace heavy metals such as Pb²⁺, Cd²⁺ and Cu²⁺, which abundantly pollute the environment, are hazardous neurotoxicants. Herein, the ability of “green” carbon dots from coffee waste (CCDs) to adsorb Pb²⁺, Cd²⁺ and Cu²⁺ in aquatic media and in biological systems, such as presynaptic rat cortex nerve terminals, was assessed. Using ICP-MS and DLS, it was demonstrated that CCDs were able to adsorb Pb²⁺, Cd²⁺ and Cu²⁺ in water, forming complexes with these metals. In animal experiments, CCDs, even at a high concentration of 2 mg ml⁻¹, did not change the extracellular levels of the excitatory neurotransmitter L-[¹⁴C]glutamate and inhibitory one [³H]GABA in nerve terminal preparations, and so, CCDs are highly biocompatible. Combined application of CCDs with Pb²⁺, Cd²⁺ and Cu²⁺ resulted in a significant mitigation of the acute Pb²⁺/Cd²⁺/Cu²⁺-induced increase in the extracellular levels of L-[¹⁴C]glutamate and [³H]GABA in nerve terminal preparations. Therefore, CCDs did not possess neurotoxic effects and, due to their original synthesis methodology, were able to adsorb Pb²⁺, Cd²⁺ and Cu²⁺ in aquatic media and in biological systems, mitigating acute Pb²⁺/Cd²⁺/Cu²⁺-induced neurotoxicity in nerve terminals. CCDs have prophylactic and therapeutic potential to combat heavy metal poisoning. This study fits several key priorities in environmental science as a heavy metal adsorbent obtained from biowaste using an eco-friendly synthesis protocol has the potential to combat heavy metal poisoning in organisms and wastewater.

Tremendous deposits of disposable medical facemask waste after the COVID-19 pandemic require improvement of waste management practice according to WHO report 2022, moreover facemasks are still in use around the world to protect against numerous airborne infections. Here, water-suspended smoke preparations from the combustion of disposable medical facemasks (polypropylene fibers) were collected; size, zeta potential, surface groups of smoke particulate matter were determined by dynamic light scattering, FTIR and Raman spectroscopy, and their optical properties were characterized. Neurochemical study using nerve terminals isolated from rat cortex revealed a significant decrease in the initial rate of the uptake/accumulation of excitatory and inhibitory neurotransmitters, L-[¹⁴C]glutamate and [³H]GABA, and exocytotic release, and also an increase in the extracellular level of these neurotransmitters. Fluorescent measurements revealed that ROS generation induced by hydrogen peroxide and glutamate receptor agonist kainate decreased in nerve terminals. A decrease in the membrane potential of nerve terminals and isolated neurons, the mitochondrial potential and synaptic vesicle acidification was also shown. Therefore, accidental or intentional utilization of disposable medical facemask waste by combustion results in the release of neuroactive ultrafine particulate matter to the environment, thereby contributing to plastic-associated pollution of air and water resources and neuropathology development and expansion.