Ultrasensitive in-vitro monitoring of monoamine neurotransmitters from dopaminergic cells

The design of biosensing assay of monoamine neurotransmitters (MANTs) such as epinephrine (Ep), norepinephrine (NE), and dopamine (DA), as well as the monitoring of these MANTs released from dopaminergic cells, are of particular interest. Electrochemical sensors based on the novel construction of nickel oxides (NiO) were fabricated and employed for electrochemical screening of MANTs. A novel NiO-lacy flower-like (NLF) geometrical structure with semi-spherical head surfaces connected with a trunk as an arm was achieved. The designed semi-spherical head associated with abundant and the well-dispersed tubular branches with needle-like open ends might lead to the creation of vascular vessels for facile diffusion and suitable accommodation of the released MANTs throughout active and wide-surface-area coverage, multi-diffusive pores, and caves with connective open macro-/meso-windows along the entire top-view nanoneedles of lacy flower head and trunk. These electrode surfaces possess high-index catalytic site facets associated with the formation of ridges/defects on {110}-top-cover surface dominants for strong binding, fast response, and signaling of MANTs. The NLF- modified electrode enabled high sensitivity for MANTs and a low limit of detection of 6 nM. Ultrasensitive in-vitro monitoring of DA released from dopaminergic cells (such as PC12) was realized. The NLF electrode was used to detect MANTs from its sources (PC12), and it could be used for clinical diagnosis

Fabrication and characterization of mesoporous silica nanochannels inside the channels of anodic alumina membrane

Brij type surfactants (CnEOx) that have different chemical structures were used to fabricate 3D Mesoporous Silica Nanochannels (MSN) inside the channels of Anodic Alumina Membrane (AAM) under acidic conditions. The fabricated 3D MSN were characterized using TEM-ED, SEM, Small angle XRD, and N2 isotherm. Results revealed that the synthesis of ordered 3D cubic Im3m mesostructures can be formed with tunable pore diameters varied from 4.0 to 4.9 nm that are partially affected with the length of ethylene oxide (EO) group in the template surfactant

Electrochemical detection of dihydronicotinamide adenine dinucleotide using Al2O3-GO nanocomposite modified electrode

NADH plays a vital role in the electron transfer processes between metabolites in the cellular energetic reactions. Therefore, there is a crucial need to develop analytical techniques for detecting NADH levels with the metabolism of glucose. In the present study, a nanocomposite of alumina (Al2O3) nanoparticles confined graphene oxide (GO) sheet acts as a modifier for carbon paste electrode (CPE) for a sensitive detection of NADH level in a mediator-less detection scheme. Our findings after optimization of experimental conditions reveal that, there is a remarkable enhancement in the direct electron transfer through the Al2O3-GO nanocomposite surface with high electrocatalytic activity towards NADH oxidation. Results show that, there is a linear increase in NADH detection from 30 µM to 330 µM, together with linear regression coefficient of 0.98 and LOD 4.5 µM. These results confirm that, the developed Al2O3-GO based CPE electrode is a promising electrode for real NADH level detection in practical enzymatic applicability. Keywords: Al2O3-GO nanocomposite, NADH, Modified electrodes, Electrochemical detectio