Computational studies on electronic and optical properties of dopamine derivatives structure: A DFT study**

Dopamine is considered an important molecule that plays several essential roles in the human body, and herein lies the key to this paper on the electronic and optical properties of dopamine and its derivatives, such as quinone and L-dihydroxyphenylalanine (L-DOPA), using DFT and TD-DFT methods, respectively. Our findings show that dopamine has a dielectric behavior, whereas quinone and L-DOPA have semiconductor behaviors in the ground and excited states. By computing the optical properties, we disclose that the electronic transition spectrum of dopamine, quinone and L-DOPA are observed in the ultra-violet region, visible spectrum, and (ultraviolet and visible regions), respectively. Other properties, such as ionization potential, electronic affinity, hardness and softness are also calculated due to their importance in sensor applications and sensing.

Stacked hexagonal prism of Ag@Ni-MOF-1 as functionalized SERS platform through rational integration of catalytic synthesis of dopamine-quinone at physiological pH with a biomimetic route

A stacked hexagonal prism, Ag@Ni-MOF-1, was developed as an integrated SERS platform not only for in situ catalyzing in situ synthesis of DA-quinone at physiological pH, but for establishing an approach for specific determination of Cys in brain.

Oxidized DJ-1 Levels in Urine Samples as a Putative Biomarker for Parkinson’s Disease

Parkinson’s disease (PD) is the second most common neurodegenerative disease. Oxidative stress is the most critical risk factor for neurodegenerative diseases, including Alzheimer’s disease (AD) and Huntington’s disease (HD). Numerous reports have demonstrated that oxidative stress aggravates cytotoxicity in dopaminergic neurons and accelerates the formation of protein inclusions. In addition, oxidative stress, such as 4-hydroxynonenal (HNE), oxidized protein, and dopamine quinone, are related to PD progression.DJ-1is a PD-causative gene, and it plays a pivotal role as a sensor and eliminator of oxidative stress. Several studies have shown that oxidized DJ-1 (OxiDJ-1) formation is induced by oxidative stress. Hence, previous studies suggest that oxidized DJ-1 could be a biomarker for PD. We previously reported higher DJ-1 levels in Korean male PD patient urine exosomes than male non-PD controls. We speculate that OxiDJ-1 levels in PD patient urine might be higher than that in non-PD controls. In this study, we established an ELISA for OxiDJ-1 using recombinant DJ-1 treated with H2O2. Using Western blot assay and ELISA, we confirmed an increase of OxiDJ-1 from HEK293T cells treated with H2O2. Using our ELISA, we observed significantly higher, 2-fold, OxiDJ-1 levels in the urine of Korean PD patients than in non-PD controls.