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The applications for lateral flow assay (LFA) strips in point-of-care testing have been significantly constrained by their insufficient sensitivity and reproducibility. To address these inherent issues, we developed surface-enhanced Raman scattering (SERS)-based LFA strips, in which highly symmetric Au nanostars (Sym-AuNS) were employed as the sensing element. Due to the uniform tip-sharp nanostructure and a certain number of branches on the surface of Sym-AuNS, it generates a uniform hotspot distribution, thus producing a strong and stable SERS signal. As a proof of concept, human IgG was chosen as the target to evaluate the performance of the proposed SERS-LFA strips. In human serum spiked samples, the limit of detection for human IgG detection was achieved as low as 38 ng/mL, which exhibited a 2-fold, 3-fold, and 13-fold sensitivity improvement compared with the SERS-LFA strips using conventional gold nanostars (AuNS), enzyme-linked immunosorbent assays (ELISA), and the conventional LFA strips, respectively. Furthermore, the SERS-LFA strips demonstrated high assay reproducibility, with a relative standard deviation of 7.75% for five repeated tests, much lower than those of SERS-LFA strips using AuNS (24.6%), ELISA (12.42%), and conventional LFA strips (31.32%). These results demonstrate that the construction of sensitive and reproducible SERS-LFA strips was obtained, and this platform using Sym-AuNS as SERS nanoparticles paves the way for a promising approach in immunoassay technology. [ABSTRACT FROM AUTHOR]

Background and Aim: Tinnitus is a common disorder of the auditory system with a rich history dating back to ancient times. This review aims to provide a historical perspective on tinnitus in Traditional Persian Medicine (TPM) by summarizing the views of TPM scholars on its etiology and treatment. Methods: A qualitative research (summative content analysis) was conducted, utilizing TPM texts to identify the historical perspectives of TPM scholars on tinnitus. The analysis focused on their understanding of tinnitus, its causes, and recommended treatments. Results: In TPM, tinnitus was referred to as Tanin and Davi. The accumulation of phlegm and internal gases in the head or ears was considered as the main cause of tinnitus, with sudden movement or ripple of these vapors leading to auditory nerve stimulation and resulting in tinnitus. TPM scholars recommended addressing the sources of these vapors, such as gastrointestinal issues, and promoting humeral balance through temperament modification and the use of medicinal herbs for treatment. Conclusion: The TPM view on tinnitus was similar to the Greco-Roman understanding of the disease, with Persian scholars expanding on its details. TPM scholars believed in addressing the underlying causes of tinnitus and promoting humeral balance to alleviate symptoms. These historical perspectives provide insight into traditional medical systems and their approaches to the management of health conditions. [ABSTRACT FROM AUTHOR]

The Omicron variant was first detected in October 2021, which evolved from the original SARS‐CoV‐2 strain and was found to possess many mutations. Immune evasion was one of the notable consequences of these mutations. Despite Omicron exhibiting increased transmissibility, the rates of hospitalizations and deaths among patients infected with this variant were substantially lower when compared to other strains. However, concluding that the Omicron variant is less severe than other variants of SARS‐CoV‐2 requires consideration of multiple factors, including the vaccination status of infected patients as well as any previous infections with other variants. This review compiled data about any reported indicators of severity in Omicron‐infected patients, including studies comparing Omicron with other variants while adjusting for confounders. A comprehensive search was conducted using different databases to target any studies about Omicron. In total, 62 studies met our inclusion criteria and were included in this study. Many studies reported a significantly reduced risk of hospitalization, ICU admission, need for oxygenation/ventilation, and death in Omicron‐infected patients compared to patients infected with other variants, such as Delta. Some studies, however, reported comparable severity in Omicron infected patients as to other variants emphasizing a substantial risk for severe illness. Furthermore, the COVID‐19 vaccines were less effective against Omicron relative to previous lineages, except after receiving the booster dose. One study recommended vaccination during pregnancy, which may help prevent future cases of severe SARS‐CoV‐2 pneumonia in neonates and young infants due to the transfer of humoral response from the mother. [ABSTRACT FROM AUTHOR]

The molecular imprinting technique has aroused great interest in preparing novel stationary phases, and the resulting materials named molecularly imprinted polymers coated silica packing materials exhibit good performance in separating diverse analytes based on their good characteristics (including high selectivity, simple synthesis, and good chemical stability). To date, mono‐template is commonly used in synthesizing molecularly imprinted polymers‐based stationary phases. The resulting materials always own the disadvantages of low column efficiency and restricted analytes, and the price of ginsenosides with high purity was very high. In this study, to overcome the weaknesses of molecularly imprinted polymers‐based stationary phases mentioned above, the multi‐templates (total saponins of folium ginseng) strategy was used to prepare ginsenosides imprinted polymer‐based stationary phase. The resulting ginsenosides imprinted polymer‐coated silica stationary phase has a good spherical shape and suitable pore structures. Additionally, the total saponins of folium ginseng were cheaper than other kinds of ginsenosides. Moreover, the ginsenosides imprinted polymer‐coated silica stationary phase‐packed column performed well in the separation of ginsenosides, nucleosides, and sulfonamides. The ginsenosides imprinted polymer‐coated silica stationary phase possesses good reproducibility, repeatability, and stability for seven days. Therefore, a multi‐templates strategy for synthesizing the ginsenosides imprinted polymer‐coated silica stationary phase is considered in the future. [ABSTRACT FROM AUTHOR]

Microcystin has been causing serious environmental pollution; however, the recognition of such compounds is still challenging because of low abundance and coexisting interfering species. In this contribution, we develop a novel microfluidic paper-based colorimetric sensor by exploiting molecular imprinting technology and Fenton reaction for on-site microcystin-RR determination in complex water samples using a smartphone. [ABSTRACT FROM AUTHOR]

A blue-, yellow- and red-emitting fluorescence sensor was constructed via the synergy of manganese dioxide (MnO2) nanosheets, o-phenylenediamine (OPD) and red-fluorescent quantum dots (r-QDs), namely MnO2-OPD-QD, for visualization of ascorbic acid (AA) and alkaline phosphatase (ALP). Initially, by virtue of the oxidase-like activity of MnO2 nanosheets, OPD was oxidized into yellow-fluorescent OPDox (emission: 569 nm), which quenched the r-QDs (emission: 659 nm). After interaction with AA, one reaction product of ALP and 2-phospho-L-ascorbic acid (AA2P), the MnO2 nanosheets were reduced and lost the oxidase-like activity, so that the generation of OPDox was lessened and the fluorescence of the r-QDs was thereupon recovered. Further increasing AA or ALP, the MnO2 nanosheets were fully decomposed so that OPD was not oxidized but was reduced into blue-fluorescent OPDred (emission: 441 nm), while the r-QDs were not affected. Overall, AA or ALP triggered emission intensity changes at 441, 569 and 659 nm and led to profuse color variation over the yellow-orange-red-purple range, realizing multiplex and visual determination of AA and ALP in the ranges of 0.5-70 mM and 0.1-100 mU mL1, respectively. The color variation range of the ternary-emission mode was greatly enlarged, especially compared with that of the single-/dual-emission mode. Accordingly, the MnO2-OPD-QD sensor provided detection limits for AA and ALP as low as 0.18 mM and 0.06 mU mL1, respectively. Furthermore, the highly selective/sensitive measurement and accurate readout of AA and ALP were accomplished in complicated food and serum samples. The multi-emitting fluorescence sensor held great potential for onsite visualization of various targets in more fields. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop a simple, sensitive and selective procedure for the preconcentration and determination of quercetin residues in Apium graveolens, Brassica oleracea, Spinacia oleracea, watercress, onion, and apple matrices. This novel method was developed on the basis of the dispersive-micro-solid phase extraction (D-μ-SPE) procedure based on a core–shell magnetic molecularly imprinted polymer (MMIP) in combination with high-performance liquid chromatography-ultraviolet (HPLC-UV). Variables affecting the quercetin extraction efficiency included pH, MIP dose, extraction contact time, elution organic solvent, and volume of organic solvent and were evaluated by the experimental central composite design (CCD). The obtained optimal parameters were as follows: pH (3.5), sorbent (12 mg), elution organic solvent and solvent volume (methanol, 0.2 mL), and elution time (22.0 min, without adding salt). The calibration curve was linear in the concentration range of 0.6–5500 μg L−1 with the lower limits of detection found in the range of 0.113–0.117 μg L−1, thereby revealing the high-sensitivity and -selectivity properties. The combination of D-μ-SPE and HPLC-UV could provide a method for the recovery of the analyte in various matrices at 22 min contact time with good reusability and excellent recoveries at four concentration levels (50, 100, 500, and 1000 μg L−1), ranging between 95.44 and 106.89% (relative standard deviation ＜6.0%). Based on competitive sorption experiments, the synthesized MMIP displays higher selectivity toward quercetin compared to non-imprinted polymers (NIPs) and other sorbents. [ABSTRACT FROM AUTHOR]

The present study attempted to develop a fast and sensitive ultrasound-assisted-dispersive-micro-solid phase extraction (UA-D-μ-SPE) method for the separation and preconcentration of albendazole (ABZ) from plasma and urine samples, using a molecularly imprinted polymer (MIP) coupled with high-performance liquid chromatography-UV (HPLC-UV). An MIP was selected as a sorbent, and the main factors viz. pH, MIP mass, sonication time, and eluent volume were optimized using CCD-RSM (central composite design-response surface methodology). Under the optimum conditions, the method showed the detection limit of 1.46, quantification of 4.86, and linear range of 10.0–6000.0 ng mL−1. The relative standard deviation and the relative recoveries of ABZ from spiked plasma and urine samples at five concentration levels (20, 50, 100, 500, and 1000 ng mL−1) were in the ranges of 1.43–5.21% and 92.48–101.40%, respectively. The kinetic sorption curve indicated that six min was sufficient to achieve sorption equilibrium for MIPNPs (MIP nanoparticles). The maximum sorption capacity was 34.9 mg g−1. All these results strongly support the high efficiency, selectivity, and sensitivity of the developed method for determining ABZ in plasma and urine samples. [ABSTRACT FROM AUTHOR]

In this work, a fast, sensitive, inexpensive and environment-friendly dispersive liquid–liquid microextraction (DLLME) technique was developed based on solidification of floating organic drops (SFOD) for the preconcentration of quercetin followed by HPLC-UV. The parameters affecting the extraction efficiency (the type of extractant and disperser solvents and their volume, sample pH, concentration of salt, and sonication time) in the DLLME-SFOD-HPLC-UV method were studied and optimized with the aid of experimental designs. The optimum conditions found were as follows: extractant solvent type and amount, 0.25 mL of dodecanol, disperser solvent type and amount, 0.70 mL of acetonitrile, pH 5.0, extraction time of 0.5 min, and no need of adding salt. Under the optimal conditions, a good linearity in the range of 0.8–3500 μg L−1 was reached; furthermore, our proposed method had a reasonable reproducibility (RSD% 1.94–5.20), repeatability (RSD% 1.01–2.82), and recovery (96.65–106.76%). In addition, a low LOD (0.149–0.165 μg L−1), high enrichment factor, and very little extraction time were attained for different aqueous matrices (Nasturtium officinale, Apium graveolens, Brassica oleracea var. sabellica, Spinacia oleracea and food samples). [ABSTRACT FROM AUTHOR]

The potentiometric characteristics of a new Cu2+‐selective electrode based on 2‐(benzyliminomethyl)‐6‐methoxy‐4‐(4‐methoxyphenyl‐azo) phenol as an efficient ionophore has been evaluated. The effects of influential parameters on the potentiometric responses such as the amount of plasticizer, the amount of ionophore, pH of the sample solution, and the effect of coexisting ions on the electrode signal were subsequently investigated. The selectivity of the electrode was assessed by calculating the selectivity coefficients using the matched potential method. The optimum ratio of the amount of materials required for the preparation of the electrode was found to be 1.7: 32.1: 64.2: 2.0 corresponding to carboxylated PVC, dimethyl sebacate as solvent mediators, potassium tetrakis (p‐chlorophenyl) borate as the anion localizing agent, and ionophore, respectively. The electrode had a fast response (7s) as well as a satisfactory Nernstian slope (29.26±0.91 mV/decade) to Cu2+ over a wide concentration range of 2.0×10−6‐ 5.0×10−2 M with a low detection limit of 5.9×10−7 M. The developed sensor was successfully used for the potentiometric titration of Cu2+ ion with EDTA and subsequently, efficient determination of this metal ion in a mineral water sample was performed. [ABSTRACT FROM AUTHOR]

A novel technique was applied for the synthesis of dummy molecularly imprinted silica nanoparticles (DMISNPs). DMISNPs were characterized by Fourier transmission infrared spectrometry, scanning electron microscopy and transmission electron microscope. The material was used as dispersant for the analysis of biscuit and bread samples using matrix solid phase dispersion (MSPD). Of advantages of such approach may be counted as the simplicity of synthesis procedure, low consumption of organic solvent, mild working temperature during the synthesis, high binding capacity and affinity. The effect of various parameters such as sample-to-dispersant ratio and eluents volume on extraction recovery was investigated and optimized by central composite design under response surface methodology. It was proven that the proposed dispersant leads to high affinity toward acrylamide even in complicated matrices. Quantification of the acrylamide was carried out by high performance liquid chromatography with UV detection (HPLC-UV). [ABSTRACT FROM AUTHOR]

Medical Humanities is an interdisciplinary field that has slowly been integrated into medical education. Despite developments in medical technologies, patients still experience feelings of grief, anger, and anxiety about their health and rely on their doctor for moral and emotional support. Thus, patients are inevitably finding doctors' empathy and understanding equally as important as their medical knowledge and clinical experience. The development and incorporation of medical humanities courses are vital for enhancing the delivery of treatment to the patient and optimizing their physical, mental, social, and emotional well-being. Nonetheless, some healthcare professionals and educators still argue that the medical field has advanced far beyond the theoretical approaches of medical humanities, especially since limited data is available to support their effectiveness. Another objection that is raised against the humanities is that the medical curriculum is already extremely rigorous, which makes it challenging to incorporate any new material into the standard coursework. Seven medical students from WCM-Q aim to uncover the potential values and limitations of medical humanities in current education and its efficacy in clinical settings. The discussion sheds light on the core skills that can be promoted by humanities including observation, listening, sensitivity, sensibility, and communication. Furthermore, the panelists engaged in a fruitful conversation exploring the narrative and scientific thinking of doctors and examining the cost-benefit analysis of modern medical practices with traditional therapeutic approaches. [ABSTRACT FROM AUTHOR]