Recent developments in nanomaterials and nanotechnology have advanced biosensing research. Two-dimensional (2D) nanomaterials or nanozymes, such as metal oxides, graphene and its derivatives, transition metal dichalcogenides, metal-organic frameworks, carbon-organic frameworks and MXenes, have garnered substantial attention in recent years owing to their unique properties, including high surface area, excellent electrical conductivity, and mechanical flexibility. Moreover, 2D nanozymes exhibit intrinsic enzyme-mimicking properties, including those of peroxidase, oxidase, catalase, and superoxide dismutase, making them well-suited for detecting biomarkers of interest and developing bio diagnostics at the point-of-care.
View Article and Find Full Text PDFEnzyme-based portable amperometric biosensors are precise and low-cost medical devices used for rapid cancer biomarker screening. Sarcosine (Sar) is an ideal biomarker for prostate cancer (PCa). Because human serum and urine contain complex interfering substances that can directly oxidize at the electrode surface, rapid Sar screening biosensors are relatively challenging and have rarely been reported.
View Article and Find Full Text PDFDisposable sensors are inexpensive, user-friendly sensing tools designed for rapid single-point measurements of a target. Disposable sensors have become more and more essential as diagnostic tools due to the growing demand for quick, easy-to-access, and reliable information related to the target. Dopamine (DA), a prevalent catecholamine neurotransmitter in the human brain, is associated with central nervous system activities and directly promotes neuronal communication.
View Article and Find Full Text PDFParkinson's disease (PD) is a neurodegenerative disorder that results in motor impairment due to dopaminergic neuronal loss. The pathology of PD is closely associated with neuroinflammation, which can be characterized by astrocyte activation. Thus, targeting the inflammatory response in astrocytes might provide a novel therapeutic approach.
View Article and Find Full Text PDFGlutamate (GLU) is a primary excitatory neurotransmitter, and its dysregulation is associated with several neurodegenerative disorders. A major challenge in GLU estimation is the existence of other biomolecules in the brain that could directly get oxidized at the electrode. Hence, highly selective electroenzymatic biosensors that enable rapid estimation of GLU are needed.
View Article and Find Full Text PDFMelatonin (MT), a pineal gland hormone, regulates the sleep/wake cycle and is a potential biomarker for neurodegenerative disorders, depression, hypertension, and several cancers, including prostate cancer and hepatocarcinoma. The amperometric detection of MT was achieved using a sensor customized with ruthenium-incorporated carbon spheres (Ru-CS), possessing C- and O-rich catalytically active Ru surfaces. The non-covalent interactions and ion-molecule adducts between Ru and CS favor the formation of heterojunctions at the sensor-analyte interface, thus accelerating the reactions towards MT.
View Article and Find Full Text PDFA novel voltammetric sensor was developed to selectively determine dopamine (DA) concentration in the presence of ascorbic acid (AA) and 3,4-dihydroxyphenylacetic acid (DOPAC). This sensor utilizes a modified pencil graphite electrode (PGE) coated with a newly synthesized poly (3,4-ethylene dioxythiophene) (PEDOT):poly (styrene sulfonate-co-2-(3-(6-Methyl-4-oxo-1,4-dihydropyrimidin-2-yl) ureido) ethyl methacrylate) (P(SS-co-UPyMA)) composite. The PEDOT:P(SS-co-UPyMA) (PPU) composite was characterized using nuclear magnetic resonance, X-ray photoelectron, and Raman spectroscopies.
View Article and Find Full Text PDFMicromachines (Basel)
August 2022
Bacterial infections in marine fishes are linked to mass mortality issues; hence, rapid detection of an infection can contribute to achieving a faster diagnosis using point-of-care testing. There has been substantial interest in identifying diagnostic biomarkers that can be detected in major organs to predict bacterial infections. Aspartate was identified as an important biomarker for bacterial infection diagnosis in olive flounder () fish.
View Article and Find Full Text PDFA voltammetric sensor for norepinephrine (NE) detection was developed by modifying a disposable screen-printed carbon electrode (SPCE) with de-bundled single-walled carbon nanotubes (D-SWCNTs). The de-bundling was carried out using a newly synthesized polymeric dispersant, a co-polymer of polystyrene sulfonate and methacrylate of lipoic acid. The D-SWCNTs/SPCE showed better sensitivity towards NE compared to the bare SPCE and that modified with bundled SWCNTs.
View Article and Find Full Text PDFBacterial infections in fish farms increase mass mortality and rapid detection of infection can help prevent its widespread. Lactate is an important biomarker for early diagnosis of bacterial infections in farmed olive flounder (). To determine the lactate levels, we designed a disposable amperometric biosensor based on Prussian blue nanozyme and lactate oxidase (LOX) entrapped in copolymer-reduced graphene oxide (P-rGO) on screen-printed carbon electrodes.
View Article and Find Full Text PDFA new disposable amperometric biosensor for sarcosine (Sar, a biomarker for prostate cancer) was designed based on screen-printed carbon electrodes, Prussian blue, polymer dispersed reduced graphene oxide (P-rGO) nanosheets, and sarcosine oxidase (SOx). Poly(sodium 4-styrenesulfonate-r-LAHEMA) denoted as PSSL was newly synthesized as dispersant for rGO. The P-rGO was utilized for SOx immobilization, the sulfonate and disulfide functionalities in PSSL enable physical adsorption of SOx and its bioactivity and stability properties were improved.
View Article and Find Full Text PDFA simple one-step electrochemical deposition/activation of graphitic carbon nitride (g-CN) is highly desired for sensor configurations and remains a great challenge. Herein, we attempt an electrochemical route to exfoliate the g-CN nanosheets in an aqueous solution of pH 7.0 for constructing a sensor, which is highly sensitive for the detection of serotonin (5-HT).
View Article and Find Full Text PDFInherited peripheral neuropathy (IPN) is caused by heterogeneous genetic mutations in more than 100 genes. So far, several treatment options for IPN have been developed and clinically evaluated using small molecules. However, gene therapy-based therapeutic strategies have not been aggressively investigated, likely due to the complexities of inheritance in IPN.
View Article and Find Full Text PDFWe have prepared a core-shell magnetic silica-coated hydroxyapatite, Fe₃O₄@SiO₂@HAp composite materials for pH-responsive drug delivery applications. Captopril (Cap) and ibuprofen (Ibu) were chosen as model hydrophilic and hydrophobic drugs, respectively. The drugs were encapsulated into the Fe₃O₄@SiO₂@HAp composite via electrostatic interactions with existing amine and carboxylic acid groups during calcium phosphate shell formation.
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