Facile Approach to Fabricate a Chemical Sensor Array Based on Nanocurcumin-Metal Ions Aggregates: Detection and Identification of DNA Nucleobases

Nanosized quantum dots-wrapped metallic particles ensembles integrated into filter disc-based analytical device for garlic evaluation. Application to monitor fake pickled garlic in balsamic vinegar

Herein, an affordable and simple analytical device is presented to portable identify of garlic in 30 min; the evaluation needs no pre-treatment of sample. The analytical device fabrication was did employing a headspace-based nanosensor array using of inexpensive materials as commercial filter discs, quantum dots (QDs), and metallic nanoparticles (MNPs). The nanoarray is fabricated by the accumulation QDs on MNPs surface, that results in the production of ensembles of QDs/MNPs. The ensembles generate diverse colorimetric profiles as "fingerprints" regarding to each garlic sample. The volatile organosulfur compounds (OSCs) of garlic can prefer binding to the MNPs comparing with QDs. The color profiles can be displayed with a smartphone camera, which can be quantitatively distinguished by chemometrics approaches. The analytical device was used to assessment of fake pickled samples in balsamic vinegar. This device proves well potential for qualitative control of garlic.

Curcumin alleviates Alzheimer's disease by inhibiting inflammatory response, oxidative stress and activating the AMPK pathway

BACKGROUND

Alzheimer's disease (AD) is a common degenerative brain disorder with limited therapeutic options. Curcumin (Cur) exhibits neuroprotective function in many diseases. We aimed to explore the role and mechanism of Cur in AD.

MATERIALS AND METHODS

Firstly, we established AD mice by injecting amyloid-β1-42 (Aβ1-42) solution into the hippocampus. Then, the AD mice received 150 mg/kg/d Cur for 10 consecutive days. The Morris water maze test was conducted to evaluate the cognitive function of the mice by hidden platform training and probe trials. To assess the spatial memory of the mice, spontaneous alternation behavior, the number of crossing the novel arm and the time spent in the novel arm during the Y-maze test was recorded. Hematoxylin and eosin (H&E) staining and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNAL) assay were performed to assess the pathological damage and apoptosis of brain tissues. The number of damaged neurons was inspected by Nissl staining. Immunohistochemical staining was then performed to detect Aβ1-42 deposition. The levels of tumor necrosis factor-α (TNF-a), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in serum and hippocampus, the contents of super oxide dismutase (SOD) and malondialdehyde (MDA) in brain tissues were assessed by enzyme-linked immunosorbent assay (ELISA). Additionally, B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), RelA (p65) protein expressions and Adenosine 5'-monophosphate-activated protein kinase (AMPK) phosphorylation were tested using Western blot.

RESULTS

Cur not only improved cognitive function and spatial memory, but also alleviated the pathological damage and apoptosis of brain tissues for AD mice. Meanwhile, upon Cur treatment, the number of damaged neurons in AD mice was decreased, the level of Aβ1-42 in AD mice was significantly decreased. Furthermore, the AD mice treated with Cur exhibited lower TNF-a, IL-6, IL-1β and MDA levels and a higher SOD content. Besides, Cur also downregulated p65 expression and upregulated AMPK phosphorylation.

CONCLUSION

Cur may improve AD via suppressing the inflammatory response, oxidative stress and activating the AMPK pathway, suggesting that Cur may be a potential drug for AD.

Iridium(III) solvent complex-based electrogenerated chemiluminescence and photoluminescence sensor array for the discrimination of bases in oligonucleotides

Development of rapid and sensitive method for the discrimination of bases in oligonucleotides is of great importance in clinical diagnosis. Here, we demonstrate the first case of single iridium(III) solvent complex-based electrogenerated chemiluminescence (ECL) and photoluminescence (PL) sensor array for the discrimination of bases in oligonucleotides. One iridium (III) solvent complex ([Ir(ppy)₂(DMSO)Cl], ppy = 2-phenylpyridine, probe 1) was designed as both ECL and PL probe while five bases (guanine, adenine, cytosine, thymine and uracil) were chosen as analytes. Two-element sensor array was built for the discrimination of five bases based on the fingerprint response of probe 1 to bases via coordination interactions. The combination of unique ECL and PL variations with principal component analysis was applied for the quantitative analysis of five bases in a linear range of 1.0 μM-10 μM and for the effective discrimination of individual base, the mixture of bases and oligonucleotides. Moreover, the sensor array was successfully applied to discriminate different mismatched ss-DNAs from HIV gene (a fully-matched ss-DNA), even at single-base difference. This work demonstrates that the sensor array using single iridium (III) solvent complex is a promising approach for the discrimination of bases with good sensitivity and simpleness in clinical diagnosis.

Highly specific fingerprinting of alkaline earth metal ions by a tunable plasmonic nanosensor array based on nanoaggregation of metallochromic dyes-AuNPs

Metal ions, specifically alkaline earth metal ions (AEMIs; Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺), have essential roles in industrial processes, medical testing, and environmental evaluation; therefore, developing sensitive detection methods capable of their contents is highly required. To this aim, we have designed an absorbance nanosensor array using three metallochromic dyes decorated on AuNPs and have monitored variations in AuNP plasmonic profiles upon the addition of AEMIs in different buffer and pH solutions. The array is designed in a tunable size of 2 × 3 × 1(2/3); as the type buffer and pH of solution are fixed, the number of dyes can be changed in three individual modes, three binary modes, and a ternary mode, respectively. Owing to the different binding affinities of AEMIs toward dyes in different buffer and pH solutions, fingerprint-like plasmonic profiles with different levels of aggregation AuNPs were generated for all modes of array. These aggregation AuNP-based fingerprint profiles in the wavelengths of 500, 525, 550, 575, 600, 625, 650, 675, 700, 725, and 750 nm were used to discriminate the AEMIs by applying pattern recognition methods including linear discrimination analysis (LDA) and hierarchical clustering analysis (HCA) to identify each AEMI in the range 2.1-24.7 μM. Accordingly, limits of detection (LODs) values of 0.013 (±3.13), 0.014 (±2.99), 0.020 (±4.17), and 0.017 (±4.31) μM were obtained the Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺, respectively. The results revealed that all the modes of array could well differentiate complex mixtures of the AEMIs. Our suggested array also exhibited a good performance in the differentiation of AEMIs in real samples and a certified reference material (CRM) sample.

Curcumin-cisplatin chemotherapy: A novel strategy in promoting chemotherapy efficacy and reducing side effects

The efficacy of chemotherapy in cancer therapy is limited due to resistance, treatment selectivity, and severe adverse effects. Immunotherapy, chemotherapy, targeted therapy, radiation, and surgery are the most common therapeutic strategies for treatment, with chemotherapy being the most successful. Nonetheless, these treatments exhibit poor effectiveness due to toxicity and resistance. Therefore, combination therapies of natural products may be used as an effective and novel strategy to overcome such barriers. Cisplatin is a platinum-based chemotherapy agent, and when administered alone, it can lead to severe adverse effects and resistance mechanism resulting in therapeutic failure. Curcumin is a polyphenolic compound extracted from turmeric (Curcuma longa) exhibiting anticancer potential with minimal adverse effects. The combination therapy of curcumin and cisplatin is a novel strategy to mitigate/attenuate cisplatin-related adverse effects and improve the barrier of resistance reducing unwanted effects. However, there are uncertainties on the efficacy of curcumin, and more in depth and high-quality studies are needed. This review aims to explain the adverse effects related to individual cisplatin delivery, the positive outcome of individual curcumin delivery, and the combination therapy of curcumin and cisplatin from nano platform as a novel strategy for cancer therapy.

A 3×3 visible-light cross-reactive sensor array based on the nanoaggregation of curcumin in different pH and buffers for the multivariate identification and quantification of metal ions

Here, a facilely constructed 3 × 3 visible-light cross reactive sensor array based on nanoaggregation of curcumin (Cur) is proposed for the identification and quantification of metal ions (MIs). Synthesis of nanocurcumin (NCur) was characterized by UV-Vis spectrophotometry, transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR). The average particle size was estimated about 5.21 ± 1.13 nm) n = 50 (. Our sensor array consists of nine receptors with distinct but overlapping specificities for 11 MIs: Al³⁺, Cd²⁺, Co²⁺, Cu²⁺, Hg²⁺, Fe²⁺, Fe³⁺, Mn²⁺, Ni²⁺, Pb²⁺, and Zn²⁺. The receptors include the nine solutions of NCur at three buffers of phosphate, ammonium, and tris each at three pH of 7, 8, and 9 (in total 9 receptors). On account of different pH and buffers, NCur-MI binding affinities can be distinguished by monitoring the UV-Vis absorbance changes. These changes are optical fingerprints that can be used to identify each MI. The absorption values in sixteen wavelengths (i.e. 332, 352, 372, 392, 412, 432, 452, 472, 492, 512, 532, 552, 572, 592, 612, and 632 nm) are considered as analytical signals to quantitatively evaluate of the absorbance responses of the sensor array. A color difference map is provided to qualitatively visualize of the colorimetric sensor array responses. Under optimal conditions, the MIs are successfully discriminated in the range of 4-48 μmol L^-1. The limit of detections (LODs) values ranged from 0.47 (for Fe³⁺) to 1.40 μmol L^-1 (for Pb²⁺). Furthermore, two different mixing sets of the MIs are prepared for multivariate multicomponent analysis. Finally, the suggested sensor array is employed to evaluate its practicability in the discrimination of MIs in samples of river water and serum. Moreover, it can identify the MIs in these samples. The sensor array presents a simple, save time, cost-effective, and environmentally friendly method for the identification and quantification of MIs.