Antioxidant and antihemolytic activities of methanol extract of Hyssopus angustifolius

This study was designed to evaluate antioxidant and antihemolytic activities of Hyssopus angustifolius flower, stem and leaf methanol extracts by employing various in vitro assays. The leaf extract showed the best activity in DPPH (63.2 ± 2.3 μg mL-1) and H2O2  (55.6 ± 2.6 μg mL-1) models compared to the other extracts. However, flower extract exhibited the highest Fe2+ chelating activity (131.4 ± 4.4 μg mL-1). The extracts exhibited good antioxidant activity in linoleic acid peroxidation and reducing power assays, but were not comparable to vitamin C. The stem (23.58 ± 0.7 μg mL-1) and leaf (26.21 ± 1 μg mL-1) extracts showed highest level of antihemolytic activity than the flower extract

Mechanistic Observation of Interactions between Macrophages and Inorganic Particles with Different Densities

Many different types of inorganic materials are processed into nano/microparticles for medical utilization. The impact of selected key characteristics of these particles, including size, shape, and surface chemistries, on biological systems, is frequently studied in clinical contexts. However, one of the most important basic characteristics of these particles, their density, is yet to be investigated. When the particles are designed for drug delivery, highly mobile macrophages are the major participants in cellular levels that process them in vivo. As such, it is essential to understand the impact of particles’ densities on the mobility of macrophages. Here, inorganic particles with different densities are applied, and their interactions with macrophages studied. A set of these particles are incubated with the macrophages and the outcomes are explored by optical microscopy. This microscopic view provides the understanding of the mechanistic interactions between particles of different densities and macrophages to conclude that the particles’ density can affect the migratory behaviors of macrophages: the higher the density of particles engulfed inside the macrophages, the less mobile the macrophages become. This work is a strong reminder that the density of particles cannot be neglected when they are designed to be utilized in biological applications

A liquid metal-based process for tuning the thermoelectric properties of bismuth indium systems

To obtain the optimum performance of thermoelectric materials, engineering their characteristics, such as crystal structures and phases, is critical. Liquid metal-based processes are great methods for controlling and tuning such properties. In this study, indium (In), of different concentrations, is introduced into bismuth (Bi) via a liquid metal-based process to tailor the crystallization arrangements and investigate the thermoelectric properties of the Bi-In systems. These systems were prepared by a liquid metal-based melting and solidification process. Thermoelectric properties, including the Seebeck coefficient, thermal conductivity, and resistivity, were analyzed using in-house built apparatus units. The sample with 2% indium concentration showed the highest Seebeck coefficient and electrical resistivity. Thermal conductivity was observed to decrease with increasing indium concentration up to 5%, followed by a reverse trend above this concentration. Dominated by the thermal conductivity effect, the sample with 5% indium concentration showed the highest average value for the figure of merit (zT) for the Bi-In systems. The zT value of this sample was nearly twice than that of the pristine bismuth. According to our analyses, this increase could be attributed to the crystal modalities of the formed BiIn crystals with optimum crystallite dimensions and distributions, along with the emergence of specific diffraction peaks, in the pool of bismuth. This study provides a facile and low-cost liquid metal-based pathway for designing thermoelectric materials by tuning their crystal structures and orientations using liquid metal-enabled processes

Adsorptive removal of Hg2+ from environmental water samples using thioglycerol-intercalated magnetic layered double hydroxides

Herein, the removal of Hg2+ from environmental water samples was carried out using a novel nanoadsorbent based on magnetite nanoparticles coated by a thioglycerol-intercalated layered double hydroxide. The prepared material was characterized using scanning electron microscopy equipped with an energy dispersive X-ray analyzer and Fourier transform infrared spectrometry. The effective parameters of the removal procedure were identified and optimized through the one-variable-at-a-time method. Under the optimal conditions, the removal characteristics of the synthesized adsorbent including selectivity, distribution coefficient, and loading capacity were calculated in the presence of some interfering ions. The removal efficiency of 94.98 together with the distribution coefficient of 5.00 � 105 mL g-1 and loading capacity of 480.69 mg g-1 showed the considerable capability of this novel adsorbent in the selective removal of Hg2+ from aqueous samples. To evaluate the performance of the synthesized adsorbent in the removal of Hg2+ from environmental water samples, the removal of the desired analyte was carried out using four different real samples. The removal procedures were conducted at the analyte concentration levels of 10.0 and 50.0 mg L-1 for each aqueous sample. The obtained results showed that the removal efficiency was in the range of 91.99-94.97, which confirmed the high performance of the synthesized adsorbent in the removal of Hg2+ from real samples. Furthermore, the relative standard deviation of as low as 4.18-6.17 showed the acceptable repeatability of this method. © 2020 The Royal Society of Chemistry

Engineering strategies for enhancing the performance of electrochemical paper-based analytical devices

Applications of electrochemical detection methods in microfluidic paper-based analytical devices (μPADs) has revolutionized the area of point-of-care (POC) testing towards highly sensitive and selective quantification of various (bio)chemical analytes in a miniaturized, low-coat, rapid, and user-friendly manner. Shortly after the initiation, these relatively new modulations of μPADs, named as electrochemical paper-based analytical devices (ePADs), gained widespread popularity within the POC research community thanks to the inherent advantages of both electrochemical sensing and usage of paper as a suitable substrate for POC testing platforms. Even though general aspects of ePADs such as applications and fabrication techniques, have already been reviewed multiple times in the literature, herein, we intend to provide a critical engineering insight into the area of ePADs by focusing particularly on the practical strategies utilized to enhance their analytical performance (i.e. sensitivity), while maintaining the desired simplicity and efficiency intact. Basically, the discussed strategies are driven by considering the parameters potentially affecting the generated electrochemical signal in the ePADs. Some of these parameters include the type of filter paper, electrode fabrication methods, electrode materials, fluid flow patterns, etc. Besides, the limitations and challenges associated with the development of ePADs are discussed, and further insights and directions for future research in this field are proposed

Polydopamine-Functionalized Carbon Nanotubes for Pipette-Tip Micro-Solid Phase Extraction of Malathion and Parathion from Environmental Samples

In this study, a polydopamine-functionalized multi-walled carbon nanotube was utilized in an efficient pipette-tip micro-solid phase extraction followed by gas chromatography-mass spectrometry for determination of two organophosphorus pesticides called malathion and parathion. All the effective parameters were optimized using a one variable at-a-time protocol. Under the optimal conditions, broad calibration curves were obtained with the linearity in the range between 0.30�200 ng mL�1. Preconcentration factors as high as 42.7 and 47.3 for malathion and parathion, respectively, were obtained along with the relative standard deviations (RSD) lower than 6.37 . Real samples analysis was carried out using the optimized technique for quantitative analysis of the target analytes in environmental water samples. Relative recoveries in the range between 89.37�101.22 show the capability of the method in real sample analysis. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinhei

Evaluation of bone mineral density in premature ovarian failure

This study was performed to evaluate whether or not early menopause and premature ovarian failure can cause an increased risk of osteoporosis. The bone mineral density (BMD) of the 2nd and 4th lumbar spine as well as femoral neck in 29 cases with secondary amenorrhea were compared with a reference data using a dual-energy X-ray absorptiometry on a bone densitometer: Serum levels of luteinizing hormone, follicular stimulating hormone, calcium and phosphorus were also measured. Both in 20-29 years and in 30-39 years, BMD were significantly lower than their normal range as compared with a reference data from a large study of the same population (P value<0.05). At lumbar vertebrae, 2 cases had osteopenia and 17 had osteoporosis while at the femoral neck, 17 cases had osteopenia and 4 osteoporosis. Only serum levels of phosphorus had positive relationship with femoral neck BMD (P value<0.05). It may be possible to decrease fracture incidence through the early diagnosis of individuals at risk by BMD. In conclusion, our study indicates that females with early onset of menopause and premature ovarian failure had lower value of BMD in both femoral neck and lumbar vertebrae implying the need for more bone health measures