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A unique method for determining chlorophyll content in microalgae is devised employing a gold interdigitated electrode (G-IDE) with a 10-µm gap, augmented by a nano-molecularly imprinted polymer (nano-MIP) and a titanium dioxide/multiwalled carbon nanotube (TiO2/MWCNT) nanocomposite. The nano-MIP, produced using chlorophyll template voids, successfully trapped chlorophyll, while the TiO2/MWCNT nanocomposite, synthesized by the sol–gel technique, exhibited a consistent distribution and anatase crystalline structure. The rebinding of procured chlorophyll powder, which was used as a template for nano-MIP synthesis, was identified with a high determination coefficient (R2 = 0.9857). By combining the TiO2/MWCNT nanocomposite with nano-MIP, the G-IDE sensing method achieved a slightly better R2 value of 0.9892 for detecting chlorophyll in microalgae. The presented G-IDE sensor showed a significant threefold enhancement in chlorophyll detection compared with commercially available chlorophyll powder. It had a detection limit of 0.917 mL (v/v) and a linear range that spanned from 10-6 to 1 mL. The effectiveness of the sensor in detecting chlorophyll in microalgae was confirmed through validation of its repeatability and reusability. [ABSTRACT FROM AUTHOR]

Polycrystalline structures of T-Nb2O5 and a remarkable H-Nb2O5 structure were successfully obtained in this work. This was achieved using a Nd:YAG laser in a pulsed laser deposition system at laser fluence values of 9.3, 13.4, 16.2, 21, and 25.2 J cm−2. Raman bands of the prepared films are shown and discussed. The optical bandgaps were estimated at 4.81 eV, 4.73 eV, 3.41 eV, 3.29 eV, and 3.21 eV. Photoluminescence (PL) analyses showed agreement with the estimated indirect bandgaps calculated from Tauc's plot for each prepared film. The surface average roughness and root-mean-square (RMS) roughness were also determined and are discussed. The surface morphology as illustrated by field-emission scanning electron microscopy (FE-SEM) reveals the obvious impact of laser energy density on the prepared films. Energy-dispersive x-ray (EDX) analyses revealed the highest stoichiometry attributed to a laser fluence of 21 J cm−2. [ABSTRACT FROM AUTHOR]

The coconut (Cocosnucifera) is renowned for its endocarp, commonly referred to as the coconut shell, which is believed to harbor a high concentration of silicon, potentially serving as a source for the production of silicon nanoparticles (SiO2NPs). This study demonstrated the synthesis of SiO2NPs derived from coconut shells and their application in the removal of metal contaminants, notably copper. SiO2NPs were synthesized with a recovery rate of 25.6%, yielding a white powder through the sol–gel method. Analysis via ultraviolet–visible (UV–Vis) spectroscopy revealed an absorbance peak maximum at 345 nm, indicative of strong surface plasmon resonance, thus confirming SiO2NPs formation. Morphological characterization conducted through field-emission scanning electron microscopy (FE-SEM) and field-emission transmission electron microscopy (FE-TEM) confirmed the smooth-faced nature of the SiO2NPs, presenting finely clumped particles with an average size of 62 nm. Furthermore, X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX) analyses exhibited distinct peaks corresponding to oxygen (O) and silicon (Si), confirming SiO2NPs formation. X-ray diffraction (XRD) analysis confirmed the amorphous nature of the particles, with a 25% weight loss observed at 500 °C according to thermogravimetric analysis (TGA). Assessment of the adsorption capacity for heavy metals from water solutions by spiking various copper (II) sulfate concentrations indicated the highest adsorption rate at 0.05 M copper, diminishing with increased copper ion concentrations. Evaluations utilizing different SiO2NPs concentrations demonstrated optimal copper (Cu) removal efficiency at 0.2 g/mL SiO2NPs. [ABSTRACT FROM AUTHOR]

A Mach–Zehnder electro-optic modulator (MZM) was designed using AFM COMSOL software and fabricate using pulse laser deposition method in this work. A successful multilayer structure of (nanoSi/nano SiO/nano LiNbO3) was prepared at optimum condition that obtained previously using theoretical simulation. Two designs were simulated depended on millimeter scale and micrometer scale for device fabrication. The second design was depended for wave guide (WG) fabrication. The size of the utilized Si WG was in the range of 0.7–3 µm, the results show that effective index tended to increase as the thickness and width of the Si WG increased, however, upon the addition of the LN layer, the effective index values decreased. The effective mode area increased in both MZM and MZM–LN devices alongside the Si WG width increment. In contrast, the effective mode area exhibited a reduction in the acquired values as the Si WG thickness increased. In the confinement variation, high confinement was noticed at a low Si WG width, while a high-order mode and low confinement were observed at a larger width. Refractive index of ( Δ n ≥ 0.13 ) is required to achieve 100 GHz electrical modulation bandwidth, and a device length of 2 cm produced significant figure of merit ( V π · L ) values in the range of 2.12–2.25. [ABSTRACT FROM AUTHOR]

Polyalthia longifolia is well-known for its abundance of polyphenol content and traditional medicinal uses. Previous research has demonstrated that the methanolic extract of P. longifolia leaves (PLME, 1 mg/mL) possesses anti-aging properties in Saccharomyces cerevisiae BY611 yeast cells. Building on these findings, this study delves deeper into the potential antiaging mechanism of PLME, by analyzing the transcriptional responses of BY611 cells treated with PLME using RNA-sequencing (RNA-seq) technology. The RNA-seq analysis results identified 1691 significantly (padj < 0.05) differentially expressed genes, with 947 upregulated and 744 downregulated genes. Notably, the expression of three important aging-related genes, SIR2, SOD1, and SOD2, showed a significant difference following PLME treatment. The subsequent integration of these targeted genes with GO and KEGG pathway analysis revealed the multifaceted nature of PLME's anti-aging effects in BY611 yeast cells. Enriched GO and KEGG analysis showed that PLME treatment promotes the upregulation of SIR2, SOD1, and SOD2 genes, leading to a boosted cellular antioxidant defense system, reduced oxidative stress, regulated cell metabolism, and maintain genome stability. These collectively increased longevities in PLME-treated BY611 yeast cells and indicate the potential anti-aging action of PLME through the modulation of SIR2 and SOD genes. The present study provided novel insights into the roles of SIR2, SOD1, and SOD2 genes in the anti-aging effects of PLME treatment, offering promising interventions for promoting healthy aging. [ABSTRACT FROM AUTHOR]

Parmotrema perlatum lichen is traditionally used as a spice in Indian households and also to treat diseases such as eczema, respiratory diseases, pulmonary diseases, and arthritis. This study emphasizes the extraction of secondary metabolites from foliose lichen P. perlatum with antioxidant and antibacterial activity. The secondary metabolites extracted from P. perlatum using hexane, chloroform, and methanol were analysed by gas chromatography-mass spectrometry (GC–MS) and liquid chromatography-mass spectrometry (LC–MS/MS) shows that P. perlatum extracts possess 2,4-dihydroxy-3,6-dimethyl-methyl ester, 1,4-benzenediol, atraric acid, orcinol, benzoic acid, 2,5-dimethyl- resorcylic acid, and savinin, tetrahydroterotri-L- glutamate, primidolol, ustiloxin, mallotinic acid, and mecambrine. The efficacy of three solvent extracts of lichen against Gram-negative bacteria Pseudomonas aeruginosa, Chromobacterium violaceum, and Gram-positive Lactobacillus plantarum was tested. The methanol extract of P. perlatum has the highest antibacterial activity against the tested bacteria at a concentration of 10 µg/ml as compared with the other two solvent extracts. The antioxidant potential of P. perlatum was determined using ferric ion reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid), and nitric oxide scavenging activity assays, which exhibit that all extracts showed radical scavenging potential. [ABSTRACT FROM AUTHOR]

Natural fibre (NFR) reinforced functional polymer composites are quickly becoming an indispensable sustainable material in the transportation industry because of their lightweight, lower cost in manufacture, and adaptability to a wide variety of goods. However, the major difficulties of using these fibres are their existing poor dimensional stability and the extreme hydrophilicity. In assessing the mechanical properties (MP) of composites, the interfacial bonding (IB) happening between the NFR and the polymer matrix (PM) plays an incredibly significant role. When compared to NFR/synthetic fibre hybrid composites, hybrid composites (HC) made up of two separate NFR are less prevalent; yet, these hybrid composites also have the potential to be valuable materials in terms of environmental issues. A new dimension to the flexibility of composites reinforced with NFR is added by the cost-effective manufacture of hybrid composites utilising NFR. The purpose of this study is to offer an overview of the key findings that were presented on hybrid composites. The emphasis was focused on the factors that influence the performance of the natural fiber composites, diverse approaches to enhancing MP, physical, electrical, and thermal characteristics of the HC. HC study in polymer science gains interest for applications in construction and automotive industries. [ABSTRACT FROM AUTHOR]

This study examines the impact of thermal annealing on ZnO nanorods produced by vapour phase transport. Nanorods were annealed at temperatures of 300, 500, and 700 °C. It has been demonstrated through X-ray diffraction that the annealing process led to an increase in crystalline size from 34 to 51 nm, indicating improved crystallinity. The optical bandgap decreased from 3.28 to 3.22 eV as a result of defect minimization during annealing. Due to increased crystallinity and fewer defects, annealing increased the dark conductivity from 0.8 to 2 S/cm, as shown by electrical experiments. After annealing, the photosensitivity increased from 10 to 35 and the responsivity rose from 0.18 to 0.48 A/W. The quantitative results demonstrate that annealing modifies the physical properties of ZnO nanorods and improves their photodetection capabilities. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid light-emitting devices have garnered significant attention in the last few years due to their potential. These devices integrate the superior electron mobility of inorganic semiconductors with the remarkable optoelectronic characteristics of organic semiconductors. The inquiry focused on analyzing the optical and electrical properties of a light-emitting heterojunction that combines p-type GaN with organic materials (PEDOT, PSS, and PMMA). This heterojunction is an organic–inorganic hybrid. The procedure entailed utilizing a spin-coating technique to apply a layer of either poly(methyl methacrylate) (PMMA) or a mixture of PMMA and poly(3,4ethylenedioxythiophene)-poly(styrene sulfonate) (PEDOT: PSS) onto an indium tin oxide (ITO) substrate. Subsequently, different Nd:YAG laser pulses (200, 250, and 300 pulses) were used to administer a GaN inorganic layer onto the prepared organic layer using a pulsed laser deposition approach. Subsequently, the thermal evaporation technique was employed to deposit an aluminum electrode on the top of the organic and inorganic layers, while laser pulses were fine-tuned for optimal performance. The Hall effect investigation verifies the p-type conductivity of the GaN material. The electroluminescence studies confirmed the production of blue light by the GaN-based devices throughout a range of voltage situations, spanning from 45 to 72 V. [ABSTRACT FROM AUTHOR]

A simplified scheme for the isolation of biosurfactant-producing actinomycetes from soils was developed using different combinations of pretreatments and selective media supplemented with antifungal agent, cycloheximide (0.1 g/l). Pretreatments using hot air-drying techniques as well as soil suspension in phosphate buffer solution (5 mM, pH 7.0) treated with peptone (6%) at 45 °C for 10 min proved to be effectual in decreasing the number of vegetative bacterial cells while preserving many actinomycetes spores. Out of 945 actinomycetes isolates collected from various types of soils, 126 isolates of distinct morphologies were screened for biosurfactant production and 28 isolates were proven positive with 18 from contaminated areas while 10 of the positive isolates were from relatively non-contaminated soils. The combination of coal-vitamin medium, supplemented with antifungal agent, cycloheximide (0.1 g/L), on soil samples treated with peptone (6%) and SDS (0.05%) in 5 mM phosphate buffer, pH 7.0, produced the highest number of actinomycetes isolates recovery. Initial screenings for biosurfactant production using combination of microplate assay, drop collapse method, emulsification activity, and tributyrin agar test were found adequate for copious isolates as these methods also assessed for both low- and high-molecular mass biosurfactant types and worked well for high throughput screening analyses. [ABSTRACT FROM AUTHOR]

Breast cancer has been reported to be high in its incidence with women, and early identification of breast cancer helps to improve and provide an effective treatment. Tumor markers are active substances; in particular, human epidermal growth factor receptor 2 (HER2) is over‐expressed at the level of 20%–30%. This research work developed a highly sensitive HER2 biosensor on the interdigitated electrode (IDE) by using aptamer as a detection probe. To enhance the analytical performances, aptamer was attached to the gold nanoparticle and immobilized on the IDE through a chemical linker [(3‐aminopropyl)triethoxysilane]. On the aptamer conjugation, HER2 was quantified through current‐volt measurements, and the limit of detection of HER2 was calculated as 1 pg/mL on a linear range from 0.1 to 3000 pg/mL at an R2 (regression coefficient) of 0.9657. Further, a selective performance with human serum increased the current responses by increasing HER2 concentrations. Specific experiments with control protein and complementary aptamer sequence failed to enhance the current responses. This HER2 biosensor reflects the occurrence of breast cancer at its lower abundance and helps to identify the associated complications. [ABSTRACT FROM AUTHOR]

Parmotrema perlatum, a lichen belonging to the family Parmeliaceae, is well known for its culinary benefits and aroma used as a condiment in Indian homes is also known as the "black stone flower" or "kalpasi" in India. This research intends to analyze the antioxidant power of the crude extracts using four pH‐based buffers solubilized proteins/peptides and RP‐HPLC fractions of P. perlatum obtained by purification. The proteins that were extracted from the four different buffers were examined using LC‐MS/MS‐based peptide mass fingerprinting. When compared to the other buffers, the 0.1 M of Tris‐HCl buffer pH 8.0 solubilized proteins/peptides had the strongest antioxidant capacity. The sequential purification of the peptide was carried out by using a 3‐kDa cut‐off membrane filter and semipreparative RP‐HPLC. Additionally, the purified fractions of the peptide's antioxidant activity were assessed, and effects were compared with those of the crude and 3 kDa cut‐‐off membrane filtrates. The peptide fractions were sequenced by LC‐MS/MS, which reveals that fraction 2 from RP‐HPLC with the sequence LSWFMVVAP has shown the highest antioxidant potential in comparison with other fractions which can serve as the potential natural antioxidant drug. Further, fraction 2 also showed antibacterial activity against the selected microorganisms. [ABSTRACT FROM AUTHOR]

Infectious diseases, caused by pathogenic microorganisms such as bacteria, viruses, parasites, or fungi, are crucial for efficient disease management, reducing morbidity and mortality rates and controlling disease spread. Traditional laboratory‐based diagnostic methods face challenges such as high costs, time consumption, and a lack of trained personnel in resource‐poor settings. Diagnostic biosensors have gained momentum as a potential solution, offering advantages such as low cost, high sensitivity, ease of use, and portability. Nanobiosensors are a promising tool for detecting and diagnosing infectious diseases such as coronavirus disease, human immunodeficiency virus, and hepatitis. These sensors use nanostructured carbon nanotubes, graphene, and nanoparticles to detect specific biomarkers or pathogens. They operate through mechanisms like the lateral flow test platform, where a sample containing the biomarker or pathogen is applied to a test strip. If present, the sample binds to specific recognition probes on the strip, indicating a positive result. This binding event is visualized through a colored line. This review discusses the importance, benefits, and potential of nanobiosensors in detecting infectious diseases. [ABSTRACT FROM AUTHOR]

This study aimed to isolate biosurfactant‐producing and hydrocarbon‐degrading actinomycetes from different soils using glycerol–asparagine and starch–casein media with an antifungal agent. The glycerol–asparagine agar exhibited the highest number of actinomycetes, with a white, low‐opacity medium supporting pigment production and high growth. Biosurfactant analyses, such as drop collapse, oil displacement, emulsification, tributyrin agar test, and surface tension measurement, were conducted. Out of 25 positive isolates, seven could utilize both olive oil and black oil for biosurfactant production, and only isolate RP1 could produce biosurfactant when grown in constrained conditions with black oil as the sole carbon source and inducer, demonstrating in situ bioremediation potential. Isolate RP1 from oil‐spilled garden soil is Gram‐staining‐positive with a distinct earthy odor, melanin formation, and white filamentous colonies. It has a molecular size of ~621 bp and 100% sequence similarity to many Streptomyces spp. Morphological, biochemical, and 16 S rRNA analysis confirmed it as Streptomyces sp. RP1, showing positive results in all screenings, including high emulsification activity against kerosene (27.2%) and engine oil (95.8%), oil displacement efficiency against crude oil (7.45 cm), and a significant reduction in surface tension (56.7 dynes/cm). Streptomyces sp. RP1 can utilize citrate as a carbon source, tolerate sodium chloride, resist lysozyme, degrade petroleum hydrocarbons, and produce biosurfactant at 37°C in a 15 mL medium culture, indicating great potential for bioremediation and various downstream industrial applications with optimization. [ABSTRACT FROM AUTHOR]

A modified photonic crystal fiber (PCF) was utilized as a biosensor, incorporating gold nanoparticles as an active plasmonic material. The finite element method (FEM) was employed to compute numerical interpretations of sensing performance using various liquids: liver blood, colon blood, human plasma, water, and pentanol. In the proposed biosensor configuration, the test sample (analyte) was placed within the core, surrounded by cladding air holes, and external to the hollow core fiber structure. Sensitivity calculations were conducted both before and after the addition of the gold overlayer. The maximum amplitude sensitivity was determined to be 769.57 RIU-1 for human plasma, accompanied by the optimal electric field of 400V/m. Similarly, in the same liquid, when the deposited photonic crystal fiber (PCF) was coated with a gold layer, the maximum amplitude sensitivity reached 975.53 RIU-1 at an optimal electric field of 477 V/m. Considering the proposed sensor as a refractive index sensor, it exclusively utilized an analyte sample within the core and air holes of the PCF. Here, the maximum amplitude sensitivity attained was 869.84 RIU-1, aligning with the best electric field value of 434 V/m." [ABSTRACT FROM AUTHOR]

Highly specific detection of tumor-associated biomarkers remains a challenge in the diagnosis of prostate cancer. In this research, Maackia amurensis (MAA) was used as a recognition element in the functionalization of an electrochemical impedance-spectroscopy biosensor without a label to identify cancer-associated aberrant glycosylation prostate-specific antigen (PSA). The lectin was immobilized on gold-interdigitated microelectrodes. Furthermore, the biosensor's impedance response was used to assess the establishment of a complex binding between MAA and PSA-containing glycans. With a small sample volume, the functionalized interdigitated impedimetric-based (IIB) biosensor exhibited high sensitivity, rapid response, and repeatability. PSA glycoprotein detection was performed by measuring electron transfer resistance values within a concentration range 0.01–100 ng/mL, with a detection limit of 3.574 pg/mL. In this study, the ability of MAA to preferentially recognize α2,3-linked sialic acid in serum PSA was proven, suggesting a potential platform for the development of lectin-based, miniaturized, and cost effective IIB biosensors for future disease detection. [ABSTRACT FROM AUTHOR]

Understanding the atomic behaviour of pure graphene is crucial in manipulating its properties for achieving optoelectronics with high absorption indexes and efficiencies. However, previous research employing the DFT approach emphasised its zero-band gap nature, not its unique optical properties. Therefore, this study employed ab initio calculations to revisit the electronic, magnetic, and optical properties of pristine graphene using the WIEN2K code. The results reveal that the PBE-GGA valence and conduction bands cross at -0.7 eV. Our calculations demonstrated that the absorption coefficient of graphene has the strongest light penetration in the parallel direction. Furthermore, our results not only present the best possible propagation of light in pure graphene but also reveal that the linear relationship between the formation of the free electron carriers and the energy absorption is responsible for the high optical conductivity observed in pure graphene, as indicated by the peaks. Lastly, the metallic properties of graphene are reflected by the variation in spin up and down that appears, as evidenced by the total and partial densities of states, and the large refractive index attributed to its high electron mobility confirms its metallic nature. [ABSTRACT FROM AUTHOR]

Sodium alginate (SA)/hydroxyapatite (HA)/graphene nanoplatelets (GP) bionanocomposite films that possess good biocompatibility for bone tissue engineering are prepared by a simple solution casting process. The prepared nanocomposite films are analyzed by XRD, SEM, EDAX, and FTIR analyses. XRD confirms the presence of hydroxyapatite and graphene nanoplatelets in the nanocomposite. FTIR spectrum confirms the interaction between the matrix and the fillers. The morphology of the fillers and nanocomposite films are observed through SEM images. The inclusion of GP with different concentrations into the biopolymer film improves the tensile strength. As a result, the loading of 0.5 wt% of graphene and 10 wt% of HA in the SA polymer shows high tensile strength when compared to the pure SA and SA filled with HA. Tensile strength gradually decreases when the loading of graphene is increased to 2.5% and 5% in the bionanocomposite film. The tensile strength of the bionanocomposite film with 10% of hydroxyapatite is increased by 17%, whereas the tensile strength of the bionanocomposite film loaded with 10% of hydroxyapatite and 0.5% graphene is increased by 99%. Biological tests, such as swelling, biodegradation tests, and biomineralization tests, confirm the biocompatibility of the nanocomposite films. [ABSTRACT FROM AUTHOR]

This study focuses on investigating the dynamic adsorption of Rhodamine B (RhB) from reduced graphene oxide (rGO) derived from oil palm waste. The synthesis of rGO from palm kernel shell (PKS) was achieved through double oxidation and carbonization method, resulting in a yield of 73.5 wt%. The reduction of oxygen-containing functionalities process using PKS was confirmed by FTIR spectroscopy, microscopic evaluation, and Xray diffraction analyses. Laboratory-scale fixed-bed experiments were conducted with various process parameters. Both PKS and rGO were used as adsorbents, and a comparison was made based on breakthrough curve analysis, adsorption capacity and percentage removal of dye. The adsorption kinetics of RhB on PKS and rGO were best described by the non-linear Yoon-Nelson model, with a high adsorption capacity of 88.32 mg/g and 195.24 mg/g respectively. Using both PKS and rGO, the maximum adsorption capacity was observed when using 10 cm bed depth column, inlet dye concentration of 5 mg/L, flow rate of 12 mL/min and pH of 7. PKS exhibited good dye removal with an efficiency of 66.54%. Meanwhile, the exothermic behavior highlighted the potential of utilizing rGO for maximum dye removal, achieving an efficiency of 90.35%. This study justifies rGO as a costeffective superior dye removal adsorbent, providing new prospect for large-scale dye removal. [ABSTRACT FROM AUTHOR]

Biomarkers are biological molecules associated with physiological changes of the body and aids in the detecting the onset of disease in patients. There is an urgent need for self-monitoring and early detection of cardiovascular and other health complications. Several blood-based biomarkers have been well established in diagnosis and monitoring the onset of diseases. However, the detection level of biomarkers in bed-side analysis is difficult and complications arise due to the endothelial dysfunction. Currently single volatile organic compounds (VOCs) based sensors are available for the detection of human diseases and no dedicated nanosensor is available for the elderly. Moreover, accuracy of the sensors based on a single analyte is limited. Hence, breath analysis has received enormous attention in healthcare due to its relatively inexpensive, rapid, and noninvasive methods for detecting diseases. This review gives a detailed analysis of how biomarker imprinted nanosensor can be used as a noninvasive method for detecting VOC to health issues early using exhaled breath analysis. [ABSTRACT FROM AUTHOR]

Optoelectronics devices and applications based on optical fibers become very popular in many applications. In this work, pure and doped Gold nanorods have been ablated at different pulsed laser wavelengths of 532 nm and 1064 nm, using pulse laser ablation in the liquid by using tattoo removal Nd: YAG laser (nanosecond pulses). The structural, morphological, optical, and photoluminescence properties of the ablated nanorods are studied and analyzed using X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Ultraviolet–Visible test, and PL tests. The obtained results showed that the results of using the shorter wavelength (second harmonic generation) of the laser used in ablation were the best in all tests and analyses. The obtained by using the second harmonic generation was the highest intensity and the longest, with a length of approximately 7 µm, and the results of optical analyzes using the visible ultraviolet rays test, and the PL test showed higher intensity in addition to a shift towards blue wavelengths caused by the denser nanorods and more crystallization. From the previously presented results, we conclude that the obtained nanorods can be used in electro-optical and photonic applications, and even in different types of optical sensors. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance (SPR) sensor is considered a breakthrough optical phenomenon. SPR sensors have significantly advanced in both technology and sensor applications. Plasmonic sensors are based on plasmonic material, affecting sensor sensitivity results. The sensitivity parameter is used to determine how the possibility of a variable of interest is affected by the surrounding environment. This parameter plays a vital role in any plasmonic sensor due to its strong impact on the results and the final decision of sensor performance. A single and dual symmetrical D-shape fiber-based plasmonic sensor was theoretically studied. The effect of the polishing depth and the dopant concentrations of GeO2 was investigated. A single D-shaped optical fiber shows that the highest peak loss was 2 dB/cm at the polishing depth of 36.5 μm and almost 0.0 dB/cm loss at 33.5 μm polishing depth. The resonance wavelength at the maximum loss was 1.47 μm. The highest wavelength sensitivity (1500 nm/RIU) for D-shaped fiber (D-SF) design at a maximum loss with a dopant concentration of 19.3% of GeO2 for the core and 50 nm thickness of Au layer. While the highest wavelength sensitivity (150 nm/RIU) for dual symmetrical D-shaped optical fiber design at a maximum loss with a dopant concentration of 19.3% of GeO2 for the core and 50 nm thickness of the Au layer. Nanorods were applied for a dual SD-SF sensor, which was successful at 1.20 and 1.21 refractive indices; the maximum sensitivity was 5000 nm/RIU with a dopant concentration of 15.3% of GeO2 for the core. To the best of our knowledge, there has been no report for analyzing dual symmetrical D-shaped optical fiber. Also, the comparison between single and symmetrical D-shaped optical fiber has not yet been presented. [ABSTRACT FROM AUTHOR]

In this work, gold nanoparticles (NPs) have been synthesized using second harmonic generation ND-YAG laser ablation in ethanol employing 532 nm and 1.064 nm wavelengths. Field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) spectroscopy, and UV–Vis absorption were employed to examine the structural, chemical, and optical properties of Au NPs. XRD results showed that all synthesized Au nanoparticles are crystalline in nature. The optical band gap upon ablation using the higher wavelength (1064 nm) was about 4.02 eV. The value of the optical band gap increases to reach a value of 4.22 eV at the shorter wavelength (532 nm). The FESEM results reveal the formation of smaller nanorod size at second harmonic generation (SHG) wavelength was found to be about 30 nm at wavelength 532 nm and 44 nm at 1064 nm. After that, finite element analysis is used to simulate the photonic crystal fiber (PCF) as biosensors, depending on the surface plasmon resonance (SPR) phenomenon using the COMSOL multiphasic program. The hollow core photonic crystal fiber (HC-PCF) HC-800 was thus overfilled with water. The confinement loss (CL) of the fundamental mode for the proposed PCF with and without the gold nanoparticles was calculated; we observe without gold NPs the CL at the water and colon tissue about 1.08E + 03 and 5.46E + 02 dB/m, while at use the deposited PCF with gold NPs, the results ensured the decrease more than in the confinement loss at the water and colon tissue about 1.01E + 03 and 3.16E + 02 dB/m with a clear shift toward higher wavelengths, also when calculating the sensitivity, to increase HC-PCF biosensor performance by using wavelength interrogation and amplitude measurements; it found the bio-liquid (colon tissue) has the best electric field using the gold nanowire (NW) layer in the biosensor equal to 68.8 V/m by comparison when without using the gold NW layer which leads to high sensitivity. [ABSTRACT FROM AUTHOR]

Edible oils play a tremendous role in the human diet. The production and consumption of edible oils have extensively increased due to their nutritional and economic significance. As a result of exponential population growth, the demand for edible oil has prompted adulteration, which has become a global crisis. Adulteration causes a variation in the fatty acid profiles, unique to each oil. The addition of adulterants is associated with gallbladder cancer, epidemic dropsy, cardiovascular diseases, hypercholesterolemia, and several other life-threatening diseases. Hence, monitoring the purity of edible oils at regular intervals has become inevitable. This study is to evaluate the quality of edible oils such as sesame, groundnut, coconut, mustard, sunflower, soybean, and olive oils by screening their fatty acids and secondary metabolites composition using gas chromatography-mass spectrometry (GC–MS) and thereby identifying the adulterants in comparison between the unrefined and refined oils. The fatty acid profiles of the unrefined oils were found to be in accordance with the literature survey, whereas the commercially available refined oils were mainly adulterated with palmitic, palmitoleic, stearic, and myristic acids. Contrastingly, numerous health-promoting secondary metabolites have been detected in unrefined oil samples. In conclusion, unrefined oils have nutritional values, and authenticity used for human consumption rather than refined edible oils. [ABSTRACT FROM AUTHOR]

The photoluminescence and optoelectronics properties are very important for gallium nitride (GaN) nanoparticles in the applications of ultraviolet and blue optoelectronic devices. In this article, GaN nanoparticles are prepared and fabricated using femtosecond pulse laser ablation in liquid (PLAL). The X-ray diffraction results confirm that the synthesized GaN NPs are crystalline with a mixture of cubic and hexagonal phases, and the nanoparticles synthesized at 532 nm exhibit better crystallinity. The field emission electron microscope (FE-SEM) results demonstrate that the porous silicon consists of a high concentration of semicircular pores with an average diameter of the pore around 20 µm. Furthermore, the optoelectronic properties of the GaN/PSi are investigated to confirm its feasibility for double-junction photodetector and its applications. The outcomes show that the maximum responsivity was 3.8 A/W at 330 nm for a photodetector fabricated at 532 nm laser wavelength. [ABSTRACT FROM AUTHOR]

Production of industrial solvents and chemicals from a renewable resource is quite appealing due to the dwindling fossil fuel reserves. It is essential to replace the utilization of plastic materials with biodegradable plastic materials like poly-lactic acid (PLA). In the current work, Pediococcus pentosaceus HLV1, a newly identified acetogenic strain, was used to produce LA from sugarcane field residue (SFR). One of the several lignocellulosic potential substrates that are readily available in tropical regions is SFR. SFR has a cellulose content of 40.3 3.5%, a hemicellulose content of 28.5 3.0%, and lignin content of 20.3 2.6%. Around 69% of the lignin and 73% of the hemicellulose were solubilized after the sequential dilute alkali and acid treatments. Cellulase was used to perform enzymatic saccharification of the pretreated substrate at a concentration of 10% (w/v), and produced 0.681of glucose per gram of pretreated biomass. 5 g/l of residual sugar and 61.5 g/l of LA were produced during the batch fermentation procedure. The actual fermentation procedure yielded a 1.12 g LA/g substrate used with a productivity of 0.86 g/L/h. HMF and furfural were reduced to 0.65 g/L and 0.15 g/L from 1.83 g/l to 0.91 g/l, respectively, after fermentation. In the polyphenols, the most inhibitory compounds vanillin and syringaldehyde were reduced to very low concentrations to 0.087 and 0.09 g/l from 0.284 to 1.536 g/l respectively. These compounds have not shown any inhibitory action on microbial growth and lactic acid production. The current study describes how SFR was sequentially acid pretreated and then enzymatically hydrolyzed to acquire the greatest amount of fermentable sugars, as well as how freshly isolated Pediococcus pentosaceus HLV1 was used it to produce lactic acid. [ABSTRACT FROM AUTHOR]

The increasing incidence of neurodegenerative diseases (NDDs) has stressed the need to develop new treatments. In this regard, alkaloids from medicinal plants are being identified and developed as inhibitors of acetylcholinesterase, other enzymes, and receptors associated with the onset of NDDs. Nardostachys jatamansi, a medicinal herb native to the Himalayan region and belonging to the Caprifoliaceae family, has long been used in Indian traditional medicine to treat neurobiological symptoms. In this study, we have isolated and identified the major alkaloids from N. jatamansi using LC–MS/MS analysis. The dried root extract of N. jatamansi contained actinidine and glaziovine as its major alkaloids. These compounds were identified using LC–MS/MS fragmentation pattern and purified by semi-preparative HPLC. The molecular docking analysis was performed for the purified alkaloids with 15 target proteins associated with NDDs pathology. Notably, actinidine and glaziovine showed better interaction energy with the acetylcholine esterase, VGF nerve growth factor, cyclin-dependent kinase, and glycogen synthase kinase when compared to the clinically used drugs memantine and tacrine. Glaziovine also showed better interaction energy when docking was performed with GluN1/GluN2B NMDA receptor, β-secretase, tyrosine phosphorylation regulation kinase, necrosis factor-kappa, adenosine A2A receptor, alpha-synuclein, beta-site amyloid precursor protein cleaving enzyme 1, c-Jun N terminal kinase, monoamine oxidase B, compared to tacrine, galantamine, and memantine. Furthermore, actinidine and glaziovine showed borderline cytotoxicity on PC12 and SH-SY 5Y cells with IC50 values ranging from 85.32 ± 0.87 μM, and 92.12 ± 0.56 μM, respectively, indicating that these alkaloids can be further developed as promising drug leads. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide is a nanomaterial with an ultrathin 2-dimensional structure, one of the most utilizing materials, which has been extensively applied in several down-stream purposes owing to its good optical, mechanical, physical, and thermal properties. The most reliable and widely used methods to get high quantity and quality of reduced graphene oxide is by chemical synthetic pathway. However, in the process of deoxygenated graphene oxide synthesis, the chemicals involved in the reaction are extremely hazardous. From this point of view, scientists have put in their effort in finding environmentally friendly methods to replace the use of a hazardous chemical reductant. Medicinal phytoextract reveals another route that can be an excellent reductant to reduce graphene oxide, due to the presence of phenolics, alkaloids, lipids, proteins, carbohydrate, terpenoids, and other nitrogen-containing compounds. Since the nature of phytoextract is clean and non-poisonous, the reduced graphene oxide obtained by using medicinal phytoextract as a reductant can then be applied in biomedical applications. This review presents the methods to synthesize graphene oxide by different approaches using various medicinal phytoextracts as a biological reductant to reduce graphene that could motivate researchers to generate and improve the cleaner methods for industrial-scale production. [ABSTRACT FROM AUTHOR]

Black cumin seed oil has been traditionally used as Karumjeerakam kuzhi thailam (Siddha formulation) in India more than 500 years ago. This study was conducted to find out the bioactive molecules present in black cumin seed oil. The oil was subjected to gas chromatography-mass spectrometry (GC–MS) and liquid chromatography-mass spectrometry (LC–MS) techniques, and the obtained results were compared with the National Institute of Standard Library to identify the presence of chemical compounds. Based on GC–MS and LC–MS analyses, several bioactive compounds were detected such as octanoic acid (m/z 144.21), benzene, 1,3-bis (1,1-dimethyl ethyl) (m/z 190.32), maculosin (m/z 260.1), capric acid (m/z 172.26), 3-ketosphingoshine (m/z 297.3), hygrine (m/z 141.1), tetradecanoic acid, ethyl ester (m/z 256.42), and 2-monomyristin (m/z 302.4). Moreover, the oil was further evaluated for its anti-bacterial activity against both Gram-positive and Gram-negative bacteria and was found that it inhibited the growth of Staphylococcus aureus and Pseudomonas aeruginosa at a concentration of 10 µg/mL. Besides, molecular docking with capric and caprylic acid from the oil has shown a stable binding affinity with major quorum-sensing proteins. Laetisaric acid showed the best binding scores among the 11 compounds selected for the study with the corresponding receptors. These interactions could provide more insight into understanding the action of the identified compounds on various targets. [ABSTRACT FROM AUTHOR]

Lead has been the major source of environmental pollution today. The removal of this pollutant has been a topic of significant importance among the scientific community. Therefore, to emphasise the quantity and specific removal of lead ion through the reactivity of lead toward NAAM was the objective of this study, and to analyse mechanisms involved in absorption and adsorption of lead. Thus, the study reports preparation of activated alumina based on green in house coupled with design of experiment (DOE) based on response surface methodology six parameters that were found significant in determining the quality NAAM produced (pH, NaOH, H2SO4, DI (H2O), and Al). The trend showed that a higher amount of aluminium, the micro-pore volume, and the adsorption cumulative volume of the pores for the activated alumina were 0.000821 cm3/g, 0.00221 cm3/g, and 0.002203 cm3/g. The produced NAAM have been tested for their potential to remove lead ion Pb2+ from wastewater, and the results have been promising. Adsorbent temperatures, dose, concentrations, contact time, and temperature have all been observed to affect the adsorption of Pb2+ onto membranes in laboratory experiments. The investigations were conducted at varying pH of the natural solution. The Langmuir and Freundlich models for the equilibrium data was well-fitting, with the maximum adsorption capacity of 25 mg of lead/g of the nanomembrane. The two model was further supported by the pseudo-second-order model introduced. The results of the experimental data revealed that the maximum removal rate for lead ion was 100% when the conditions were perfect. During the first 5 min, the sorption of lead ion on the membrane was rapid, and equilibrium was achieved in less than 20 min and confirmed by the Langmuir and Freundlich models and as well as the pseudo-second-order model where the kinetic of the lead on adsorption obeyed with the model. Thus, when it came to the removal of lead ion from aqueous solution, the membrane tested in this study shows excellent potential. [ABSTRACT FROM AUTHOR]

Rice tends to accumulate heavy metals present in soil that have been introduced by human activities and pass them up the food chain. The present study aimed to evaluate the accumulation of selected trace elements (Cu, Zn, and Pb) in paddy and soil and the transfer of these metals from soil to rice by analysing the bioconcentration factor (BCF), bioaccumulation factor (BAF), and translocation factor (TF) of heavy metals in paddy (Oryza sativa L.) and soil. Samples of matured paddy and the substrates were collected from three different areas located near a rural point (RP), a transportation point (TP), and an industrial point (IP). Heavy metal concentrations present in the soil and various parts of the plants were ascertained using an atomic absorption spectrophotometer (AAS). Cu, Zn, and Pb accumulation in the soil were detected in increasing orders of RP > TP > IP, IP > TP > RP, and IP > RP > TP, respectively. The BCFshoot, BAF, and transfer factor of both Zn and Pb from soil to rice were detected in the order of TP > IP > RP, which was different from Cu, where BCFshoot and TF showed the order of RP > IP > TP but the BAF indicated IP > RP > TP. TF > 1 was discovered for Zn and Pb at the TP, and for Cu at the RP, which could be attributed to the TP's strongly acidic soil and Cu's abundance in the RP's soil. Paddy height and yield traits were the most significant at the IP site, showing the highest number of fertile spikelets, the average weight of a 1000-paddy spikelet, and the harvest index (0.56). These findings can be related to the normal range of Zn and Pb found in rice plants that support growth. Thus, the findings of this study demonstrated that soil properties and metal abundance in soil from certain land use practices can partially influence the mobility and transfer of metals through soil–plant pathways. [ABSTRACT FROM AUTHOR]

Microplastic pollution is becoming a major issue for human health due to the recent discovery of microplastics in most ecosystems. Here, we review the sources, formation, occurrence, toxicity and remediation methods of microplastics. We distinguish ocean-based and land-based sources of microplastics. Microplastics have been found in biological samples such as faeces, sputum, saliva, blood and placenta. Cancer, intestinal, pulmonary, cardiovascular, infectious and inflammatory diseases are induced or mediated by microplastics. Microplastic exposure during pregnancy and maternal period is also discussed. Remediation methods include coagulation, membrane bioreactors, sand filtration, adsorption, photocatalytic degradation, electrocoagulation and magnetic separation. Control strategies comprise reducing plastic usage, behavioural change, and using biodegradable plastics. Global plastic production has risen dramatically over the past 70 years to reach 359 million tonnes. China is the world's top producer, contributing 17.5% to global production, while Turkey generates the most plastic waste in the Mediterranean region, at 144 tonnes per day. Microplastics comprise 75% of marine waste, with land-based sources responsible for 80–90% of pollution, while ocean-based sources account for only 10–20%. Microplastics induce toxic effects on humans and animals, such as cytotoxicity, immune response, oxidative stress, barrier attributes, and genotoxicity, even at minimal dosages of 10 μg/mL. Ingestion of microplastics by marine animals results in alterations in gastrointestinal tract physiology, immune system depression, oxidative stress, cytotoxicity, differential gene expression, and growth inhibition. Furthermore, bioaccumulation of microplastics in the tissues of aquatic organisms can have adverse effects on the aquatic ecosystem, with potential transmission of microplastics to humans and birds. Changing individual behaviours and governmental actions, such as implementing bans, taxes, or pricing on plastic carrier bags, has significantly reduced plastic consumption to 8–85% in various countries worldwide. The microplastic minimisation approach follows an upside-down pyramid, starting with prevention, followed by reducing, reusing, recycling, recovering, and ending with disposal as the least preferable option. [ABSTRACT FROM AUTHOR]

Transistor-based sensors have been widely recognized to be highly sensitive and reliable for point-of-care/bed-side diagnosis. In this line, a range of cutting-edge technologies has been generated to elevate the role of transistors for biomolecule detection. Detection of a wide range of clinical biomarkers has been reported using various configurations of transistors. The inordinate sensitivity of transistors to the field-effect imparts high sensitivity toward wide range of biomolecules. This overview has gleaned the present achievements with the technological advancements using high performance transistor-based sensors. This review encloses transistors incorporated with a variety of functional nanomaterials and organic elements for their excellence in selectivity and sensitivity. In addition, the technological advancements in fabrication of these microdevices or nanodevices and functionalization of the sensing elements have also been discussed. The technological gap in the realization of sensors in transistor platforms and the resulted scope for research has been discussed. Finally, foreseen technological advancements and future research perspectives are described. [ABSTRACT FROM AUTHOR]

Microcrystalline cellulose (MCC) is a green material that has widespread applications in pharmaceuticals, food, cosmetics, and other industries because of its biocompatibility, biodegradability, hydrophilicity, and acidinsolubility. In this study, MCC was prepared from cotton waste via alkaline treatment and sulfuric acid hydrolysis. Further, the synthesized cottonbased MCC was characterized using Fourier transform infrared (FTIR), Xray photoelectron, and energy dispersive X-ray spectroscopies. Based on these results, the major components were identified as carbon and oxygen. This finding was evidenced by the FTIR analysis, which displayed peak wavenumbers at 3446.9, 2891.1, 1649.5, 1380.1, 1061.2, and 1050 to 1150 cm-1 . The surface morphology was also examined by field emission scanning electron microscopy and field emission transmission electron microscopy, which showed that the prepared MCC has a smooth surface and a consistent, rod-like shape. In addition, the MCC exhibited the typical diffraction peaks of a crystalline structure of cellulose II at 12.2°, 20°, and 22.03°, which correspond to the diffraction planes of 1-10, 110, and 020, respectively, and had a crystallinity index of 78.7%. Moreover, the prepared MCC had a diameter of 37.8 µm and exhibited good stability with a peak at -76.5 mV. Further, the cotton-based MCC exhibited high thermal stability, as revealed by the TGA. [ABSTRACT FROM AUTHOR]

For decades, a Pap smear test has been applied as a conventional method in detecting Human Papillomavirus caused cervical cancer. False-positive results were also recorded while using it as conventional method. Current biosensor such as Hybrid (II) Capture resulted in higher time consumption and cost. s Meanwhile, in this study we provided facile, mini, rapid, highly sensitive, eco-friendly, and cost-effective sensing system focusing on HPV strain 58 (HPV58) in a nano-size lab-on-chip technology genosensor. 30-mer of virus ssDNA designed and analyzed as a probe via bioinformatics tools such as GenBank, Basic Local Alignment Searching Tools (BLAST) and ClustalW. Nanotechnology-developed colloidal Gold-nanoparticles (AuNPs) are used in the biosensor fabrication to produce high stability and electron efficient transmission during electrical measurement. AuNPs-APTES modified on active sites of IDEs, followed by immobilization of specific probe ssDNA for HPV 58. Hydrogen binding during hybridization with its target produce electrical signals measured by KEITHLEY 2450 (Source Meter). The genosensor validated with different types of targets such as complimentary, noncomplementary and single mismatch oligonucleotides. The serial dilution of target concentration has been experimented triplicate (n=3) range from 1fM to 10µM. The slope of calibration curve resulted 2.389E-0 AM-1 with regression coefficient (R2) = 0.97535. [ABSTRACT FROM AUTHOR]

Up to present, no study has reported on the use of silicon carbide nanomaterials (SiCNMs) as susceptor for microwave welding of thermoplastics. Therefore, in this study, silicon carbide nanowhiskers (SiCNWs) was attempted as the microwave susceptor for the microwave welding of polypropylene (PP). It was observed that SiCNWs are capable of absorbing microwave and converting them into heat, leading to a sharp increase in temperature until it reaches the melting point of PP substrates. The microwave welded joint is formed after the molten PP at the interface between PP substrates is cooled under pressure. The effect of microwave heating duration and solid loading of SiCNWs suspension was studied and reported. The formation mechanism of SiCNWs reinforced PP welded joint was proposed in this study.With these remarkable advantages of microwave welding and enhanced mechanical properties of the welded joint, it is believed that this study can provide a new insight into welding of thermoplastic and material processing through short-term microwave heating. [ABSTRACT FROM AUTHOR]

With advancements in bionanotechnology, the field of nanobiocatalysts has undergone rapid growth and revolutionized various nanomaterials as novel and fascinating nanocarriers for enzyme immobilization. Nanotubes, nanofibers, nanopores, nanoparticles, and nanocomposites have been successfully developed and used as nanocarriers. The construction of robust nanobiocatalysts by combining enzymes and nanocarriers using various enzyme immobilization techniques is gaining incredible attention because of their extraordinary catalytic performance, high stability, and ease of reusability under different physical and chemical conditions. Creating appropriate surface chemistry for nanomaterials promotes their downstream applications. This review discusses enzyme immobilization on nanocarriers and highlights the techniques, properties, preparations, and applications of nanoimmobilized enzymes. [ABSTRACT FROM AUTHOR]

In severe cases, Parkinson's disease causes uncontrolled movements known as motor symptoms such as dystonia, rigidity, bradykinesia, and tremors. Parkinson's disease also causes non-motor symptoms such as insomnia, constipation, depression and hysteria. Disruption of dopaminergic and non-dopaminergic neural networks in the substantia nigra pars compacta is a major cause of motor symptoms in Parkinson's disease. Furthermore, due to the difficulty of clinical diagnosis of Parkinson's disease, it is often misdiagnosed, highlighting the need for better methods of detection. Treatment of Parkinson's disease is also complicated due to the difficulties of medications passing across the blood–brain barrier. Moreover, the conventional methods fail to solve the aforementioned issues. As a result, new methods are needed to detect and treat Parkinson's disease. Improved diagnosis and treatment of Parkinson's disease can help avoid some of its devastating symptoms. This review explores how nanotechnology platforms, such as nanobiosensors and nanomedicine, have improved Parkinson's disease detection and treatment. Nanobiosensors integrate science and engineering principles to detect Parkinson's disease. The main advantages are their low cost, portability, and quick and precise analysis. Moreover, nanotechnology can transport medications in the form of nanoparticles across the blood–brain barrier. However, because nanobiosensors are a novel technology, their use in biological systems is limited. Nanobiosensors have the potential to disrupt cell metabolism and homeostasis, changing cellular molecular profiles and making it difficult to distinguish sensor-induced artifacts from fundamental biological phenomena. In the treatment of Parkinson's disease, nanoparticles, on the other hand, produce neurotoxicity, which is a challenge in the treatment of Parkinson's disease. Techniques must be developed to distinguish sensor-induced artifacts from fundamental biological phenomena and to reduce the neurotoxicity caused by nanoparticles. [ABSTRACT FROM AUTHOR]

In the last few decays, the fiber-optic was employed in the field of sensing because of its benefits in contrast to other types of sensors such as small size, easy to fabricate, high response, and flexibility. In this study, unclad single mode fiber-optic sensor is proposed to operate at 650 nm wavelength. COMSOL Multiphysics 5.1 finite element method (FEM) is used to design the sensor and tested it theoretically. The middle portion of the fiber cladding is removed and replaced by gold nanoparticles (Au NPs) of 50 nm thickness. Analytic layer of 3 μm thickness was immersed in different liquids in range of refractive index (RI) from 1.000281 to 1.39. These liquids are NaCl Deionized (DI) water solution, sucrose-Deionized (DI) water solution, and glycerol solution Deionized (DI) water. It was found that the highest obtained sensitivity and resolution are for glycerol-DI water solution with value of 3157.98 (nm/RIU) and 3.16 × 10–5 (RIU), respectively. Furthermore, it is easy to fabricate and of low cost. In experiments, pulsed laser ablation (PLA) was used to prepare Au NPs. X-ray diffraction (XRD) shown that the peak of the intensity grew as the ablated energy increased as well as the structure crystallization. Transmission electron microscopy (TEM) revealed an average diameter of 30 nm at the three ablated energies, while X-ray spectroscopy (EDX) spectrum has indicated the presence of Au NPs in the prepared solution. The photoluminescence (PL) and ultraviolet–visible UV–Vis transmission were used to study the optical properties of the prepared Au NPs. An optical spectrum analyzer was used to obtain the sensor's output results. It has shown that best intensity was obtained for sucrose which confined with theoretical results. [ABSTRACT FROM AUTHOR]

Coronavirus disease (COVID-19) has killed millions of people since first reported in Wuhan, China, in December 2019. Intriguingly, Withania somnifera (WS) has shown promising antiviral effects against numerous viral infections, including SARS-CoV and SARS-CoV-2, which are contributed by its phytochemicals. This review focused on the updated testing of therapeutic efficacy and associated molecular mechanisms of WS extracts and their phytochemicals against SARS-CoV-2 infection in preclinical and clinical studies with the aim to develop a long-term solution against COVID-19. It also deciphered the current use of the in silico molecular docking approach in developing potential inhibitors from WS targeting SARS-CoV-2 and host cell receptors that may aid the development of targeted therapy against SARS-CoV-2 ranging from prior to viral entry until acute respiratory distress syndrome (ARDS). This review also discussed nanoformulations or nanocarriers in achieving effective WS delivery to enhance its bioavailability and therapeutic efficacy, consequently preventing the emergence of drug resistance, and eventually therapeutic failure. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) is highly related to cardiac arrest leading to death and organ damage. Radiological techniques and electrocardiography have been used as preliminary tests to diagnose MI; however, these techniques are not sensitive enough for early‐stage detection. A blood biomarker‐based diagnosis is an immediate solution, and due to the high correlation of troponin with MI, it has been considered to be a gold‐standard biomarker. In the present research, the cardiac biomarker troponin I (cTnI) was detected on an interdigitated electrode sensor with various surface interfaces. To detect cTnI, a capture aptamer‐conjugated gold nanoparticle probe and detection antibody probe were utilized and compared through an alternating sandwich pattern. The surface metal oxide morphology of the developed sensor was proven by microscopic assessments. The limit of detection with the aptamer‐gold‐cTnI‐antibody sandwich pattern was 100 aM, while it was 1 fM with antibody‐gold‐cTnI‐aptamer, representing 10‐fold differences. Further, the high performance of the sensor was confirmed by selective cTnI determination in serum, exhibiting superior nonfouling. These methods of determination provide options for generating novel assays for diagnosing MI. [ABSTRACT FROM AUTHOR]

Mycoplasma pneumoniae is a highly infectious bacterium and the major cause of pneumonia especially in school‐going children. Mycoplasma pneumoniae affects the respiratory tract, and 25% of patients experience health‐related problems. It is important to have a suitable method to detect M. pneumoniae, and gold nanoparticle (GNP)‐based colorimetric biosensing was used in this study to identify the specific target DNA for M. pneumoniae. The color of GNPs changes due to negatively charged GNPs in the presence of positively charged monovalent (Na+) ions from NaCl. This condition is reversed in the presence of a single‐stranded oligonucleotide, as it attracts GNPs but not in the presence of double‐stranded DNA. Single standard capture DNA was mixed with optimal target DNA that cannot be adsorbed by GNPs; under this condition, GNPs are not stabilized and aggregate at high ionic strength (from 100 mM). Without capture DNA, the GNPs that were stabilized by capture DNA (from 1 μM) became more stable under high ionic conditions and retaining their red color. The GNPs turned blue in the presence of target DNA at concentrations of 1 pM, and the GNPs retained a red color when there was no target in the solution. This method is useful for the simple, easy, and accurate identification of M. pneumoniae target DNA at higher discrimination and without involving sophisticated equipment, and this method provides a diagnostic for M. pneumoniae. [ABSTRACT FROM AUTHOR]

Viruses have spread throughout the world and cause acute illness or death among millions of people. There is a growing concern about methods to control and combat early-stage viral infections to prevent the significant public health problem. However, conventional detection methods like polymerase chain reaction (PCR) requires sample purification and are time-consuming for further clinical diagnosis. Hence, establishing a portable device for rapid detection with enhanced sensitivity and selectivity for the specific virus to prevent further spread becomes an urgent need. Many research groups are focusing on the potential of the electrochemical sensor to become a key for developing point-of-care (POC) technologies for clinical analysis because it can solve most of the limitations of conventional diagnostic methods. Herein, this review discusses the current development of electrochemical sensors for the detection of respiratory virus infections and flaviviruses over the past 10 years. Trends in future perspectives in rapid clinical detection sensors on viruses are also discussed. Key points: • Respiratory related viruses and Flavivirus are being concerned for past decades. • Important to differentiate the cross-reactivity between the virus in same family. • Electrochemical biosensor as a suitable device to detect viruses with high performance. [ABSTRACT FROM AUTHOR]

Medicinal plants are an essential source of traditional curatives for numerous skin diseases. Polyalthia longifolia (Sonn.) Thwaites (Annonaceae family) is a medicinal plant used to cure skin illnesses. P. longifolia is usually applied in folkloric therapeutical systems to treat skin diseases. The methicillin-resistant Staphylococcus aureus (MRSA) bacteria is among the essential bacteria contributing to skin diseases. Hence, to verify the traditional medicinal claim of P. longifolia usage in skin disease treatment, the current research was performed to study the synergistic antibacterial activity of standardized Polyalthia longifolia methanol leaf extract (MEPL) against MRSA bacteria. The synergistic antimicrobial activity result of ceftriaxone, when mixed with MEPL, against MRSA was investigated by the disc diffusion method, broth microdilution method, checkerboard dilution test, and modulation of mecA gene expression by multiplex polymerase chain reaction (multiplex PCR). The MEPL extract exhibited good synergistic antimicrobial activity against MRSA. Using the checkerboard method, we confirmed the synergistic effect of MEPL from P. longifolia and ceftriaxone (2:1) for MRSA with a marked reduction of the MIC value of the ceftriaxone from 8000 µg/mL to 1000 µg/mL. Moreover, the combination of MEPL with ceftriaxone significantly (p < 0.05) inhibited the presence of the resistant mecA gene in the tested strain. The LC–ESI–MS/MS analysis identified compounds that were reported to exhibit antimicrobial activity. Conclusively, the MEPL extract, an important etiological agent for skin diseases, showed worthy synergistic antimicrobial action against MRSA bacteria, thus supporting the traditional use of P. longifolia. [ABSTRACT FROM AUTHOR]

SLC1A2 is a gene encoded for the excitatory amino acid transporter 2 which is responsible for glutamate reuptake from the synaptic cleft in the central nervous system. Recent studies have suggested that polymorphisms on glutamate transporters can affect drug dependence, leading to the development of neurological diseases and psychiatric disorders. Our study investigated the association of rs4755404 single nucleotide polymorphism (SNP) of the SLC1A2 gene with methamphetamine (METH) dependence and METH-induced psychosis and mania in a Malaysian population. The rs4755404 gene polymorphism was genotyped in METH-dependent male subjects (n = 285) and male control subjects (n = 251). The subjects consisted of the four ethnic groups in Malaysia (Malay, Chinese, Kadazan-Dusun, and Bajau). Interestingly, there was a significant association between rs4755404 polymorphism and METH-induced psychosis in the pooled METH-dependent subjects in terms of genotype frequency (p = 0.041). However, there was no significant association between rs4755404 polymorphism and METH dependence. Also, the rs455404 polymorphism was not significantly associated with METH-induced mania for both genotype frequencies and allele frequencies in the METH-dependent subjects, regardless of stratification into the different ethnicities. Our study suggests that the SLC1A2 rs4755404 gene polymorphism confers some susceptibility to METH-induced psychosis, especially for those who carry the GG homozygous genotype. [ABSTRACT FROM AUTHOR]

Rice is being increasingly exposed to inorganic arsenic and this affects half of the world population because they are rice consumers. In this study, pot experiments were carried out to investigate the effect of two dose-dependent nanomaterials (silica and graphene) treatment on varied arsenic levels (2, 7 and 12 mg/kg). The results showed that both nanomaterials were affected significantly with 1 mg/mL of nanomaterial. Arsenic adversely affected the plant height, tillering, number of grains, and grain weight and when high concentrations of arsenic were applied at 12 mg/kg, the plant could not withstand it and died before 75 days even in the presence of graphene. Based on inductively coupled plasma mass spectrometry analysis, silica nanoparticles showed the highest inhibition on the total accumulation of arsenic as 93% (control plant), 84% (2 mg/kg), 67% (7 mg/kg) to 35 % (12 mg/kg), whereas graphene showed lower inhibition percentages. This outcome confirms that silica nanoparticles prevent arsenic uptake, because they translocate from the root to the grains and are able to offer a promising way to reduce consumer health risk. [ABSTRACT FROM AUTHOR]