Fully automated station for testing, characterizing and modifying screen-printed electrodes.

Electrochemical detection systems that provide either quantitative or sample-to-answer information are promising for various analytical applications in the emerging field of point-of-care testing (POCT). Nevertheless, in mobile POC systems optical detection is currently more preferred compared to electrochemical detection due to the insufficient robustness of electrochemical detection approaches toward "real world" use. Over the last couple of decades, screen-printed electrodes (SPEs) have emerged as a simple and low-cost electrochemical detection platform. Here, we report, firstly and solely, a novel benchtop system for the processing of electrochemical methods on SPE platforms. Our solution prevents operator errors from occurring while processing and testing SPEs, achieves an automatic processing of more than 300 electrodes per day and enables comparative testing due to the presence of two simultaneous working channels; furthermore, the SPEs used can be stored in specially-designed cartridges. This novel device helps to overcome the major disadvantages in processing SPE technology, such as a low level of automation and issues with process repeatability, making this technology more efficient and enabling faster growth in industry.

Recent advances and current trends in brain-computer interface research and their applications.

Brain-computer interface (BCI) provides direct communication between the brain and an external device. BCI systems have become a trendy field of research in recent years. These systems can be used in a variety of applications to help both disabled and healthy people. Concerning significant BCI progress, we may assume that these systems are not very far from real-world applications. This review has taken into account current trends in BCI research. In this survey, 100 most cited articles from the WOS database were selected over the last 4 years. This survey is divided into several sectors. These sectors are Medicine, Communication and Control, Entertainment, and Other BCI applications. The application area, recording method, signal acquisition types, and countries of origin have been identified in each article. This survey provides an overview of the BCI articles published from 2016 to 2020 and their current trends and advances in different application areas.

Cushings syndrome in pregnancy caused by an adrenal adenoma.

OBJECTIVE: The description of a rare case of Cushings syndrome caused by an adrenal adenoma in pregnancy with successful treatment. CASE PRESENTATION: 30-ear-old Gravida 3 female was admitted to our hospital with hypertension at the 18th week of gestation. Hormonal analyses revealed primary Cushings syndrome with high plasma cortisol levels and low levels of adrenocorticotropic hormone. Magnetic resonance imaging demonstrated a mass on the right-side of the adrenal gland. Adrenalectomy was performed in the 28th week of gestation and the following histopathology revealed an adrenocortical adenoma. Pregnancy continued until the 38th week of gestation with glucocorticoid replacement therapy and the patient gave birth vaginally to a healthy boy in the 38th week of gestation. CONCLUSION: Cushings syndrome in pregnancy rarely occurs; dia-gnosis may be dismissed or determined after birth in most cases. Misdia-gnosis of Cushings syndrome is common because of physiological increase of corticotropin hormones and cortisol levels and overlapping symptoms that can occur even during physiological pregnancy. Cushings syndrome should have a place in the differential dia-gnosis of hypertension in pregnancy (especially before the 20th week of gestation). Analysis of the urinary free cortisol level and circadian rhythm blood cortisol can provide a reasonable strategy to dia-gnose Cushings syndrome in pregnant women. Early dia-gnosis and surgical treatment can significantly reduce maternal and fetal complications.

Nanoparticle-drug conjugates treating bacterial infections.

The ever increasing scenario of bacterial resistance against commonly available antibiotics is becoming a global threat of major concern, which necessitates the development of new strategies to overcome this hurdle. Conjugation of nanoparticles (NPs) with antimicrobial moieties, such as antibiotics, peptides or different biomolecules, has been one of the successful techniques in targeting antibiotic resistance. This review mainly focusses on the possible nanoparticle-drug conjugates with their activity against pathogenic bacterial infections. Nanoparticles play an array of roles, e.g. as a carrier, synergistically acting agent and as theranostic agent, henceforth facilitates the efficacy of therapy. Moreover, this review elaborates the studies with reported nanoparticles-drug conjugates that include their possible synthesis methodologies and applications. In most of the cases, the nanoparticles were found to increase the permeability of bacterial cell membrane, which enables higher uptake of antibiotics inside the bacterial cells which in return showed better effects. Even the conjugates were found to efficiently kill the antibiotic-resistant strains. Since several limitations are exerted by the biological systems, there is an urge for the advancement of nanoparticle-drug conjugates for better proficiency.

Electrochemical Evaluation of Selenium (IV) Removal from Its Aqueous Solutions by Unmodified and Modified Graphene Oxide.

The removal of selenium from superficial and waste water is a worldwide problem. The maximum limit according to the World Health Organization (WHO) for the selenium in the water is set at a concentration of 10 µg/L. Carbon based adsorbents have attracted much attention and recently demonstrated promising performance in removal of selenium. In this work, several materials (iron oxide based microparticles and graphene oxides materials) and their composites were prepared to remove Se(IV) from water. The graphene oxides were prepared according to the simplified Hummer's method. In addition, the effect of pH, contact time and initial Se(IV) concentration was tested. An electrochemical method such as the differential pulse cathodic stripping voltammetry was used to determine the residual selenium concentration. From the experimental data, Langmuir adsorption model was used to calculate the maximum adsorption capacity. Graphene oxide particles modified by iron oxide based microparticles was the most promising material for the removal of Se(IV) from its aqueous solution at pH 2.0. Its adsorption efficiency reached more than 90% for a solution with given Se(IV) concentration, meanwhile its maximal recorded adsorption capacity was 18.69 mg/g.

Assessment of phytotoxicity, environmental and health risks of historical urban park soils.

Urban soil areas can be contaminated with potentially dangerous heavy metals (HM), which might have got there by means of the human activity. The aim of the present study was to determine the contamination level of the city park soils and its impact on urban ecosystem. The indices assessing soil contamination such as Enrichment Factor (EF), Geoaccumulation Index (Igeo), Nemerow Pollution Index (IPIN), and indices assessing health risks, namely Hazard Index (HI) and Carcinogenic Risk (CR), have been calculated. Furthermore, the phytotoxic effect of the soil samples has been determined. The soil contains in average 58.6 mg/kg Zn, 0.3 mg/kg Cd, 27.2 mg/kg Pb and 16.6 mg/kg Cu. Based on EF index, it has been confirmed that the increased amounts of Zn, Cd and Pb in the soil are of the anthropogenic origin. The soil may be classified as moderately to strongly polluted in the case of Zn and Pb according to Igeo. Nevertheless, soil contamination in the park is at a safe level as per IPIN. Based on HI and CR indices, it is possible to state that the soil in the park does not pose any health risks. Subject to the outcomes of the toxicity test, the concentrations of HMs found out in the soils are not inhibitory for plants.

Determination of Zinc, Cadmium, Lead, Copper and Silver Using a Carbon Paste Electrode and a Screen Printed Electrode Modified with Chromium(III) Oxide.

In this study, the preparation and electrochemical application of a chromium(III) oxide modified carbon paste electrode (Cr-CPE) and a screen printed electrode (SPE), made from the same material and optimized for the simple, cheap and sensitive simultaneous determination of zinc, cadmium, lead, copper and the detection of silver ions, is described. The limits of detection and quantification were 25 and 80 µg·L-1 for Zn(II), 3 and 10 µg·L-1 for Cd(II), 3 and 10 µg·L-1 for Pb(II), 3 and 10 µg·L-1 for Cu(II), and 3 and 10 µg·L-1 for Ag(I), respectively. Furthermore, this promising modification was transferred to the screen-printed electrode. The limits of detection for the simultaneous determination of zinc, cadmium, copper and lead on the screen printed electrodes were found to be 350 µg·L-1 for Zn(II), 25 µg·L-1 for Cd(II), 3 µg·L-1 for Pb(II) and 3 µg·L-1 for Cu(II). Practical usability for the simultaneous detection of these heavy metal ions by the Cr-CPE was also demonstrated in the analyses of wastewaters.

Site-Directed Conjugation of Antibodies to Apoferritin Nanocarrier for Targeted Drug Delivery to Prostate Cancer Cells.

Herein, we describe a novel approach for targeting of ubiquitous protein apoferritin (APO)-encapsulating doxorubicin (DOX) to prostate cancer using antibodies against prostate-specific membrane antigen (PSMA). The conjugation of anti-PSMA antibodies and APO was carried out using HWRGWVC heptapeptide, providing their site-directed orientation. The prostate-cancer-targeted and nontargeted nanocarriers were tested using LNCaP and HUVEC cell lines. A total of 90% of LNCaP cells died after treatment with DOX (0.25 µM) or DOX in nontargeted and prostate-cancer-targeted APO, proving that the encapsulated DOX toxicity for LNCaP cells remained the same. Free DOX showed higher toxicity for nonmalignant cells, whereas the toxicity was lower after treatment with the same dosage of APO-encapsulated DOX (APODOX) and even more in prostate-cancer-targeted APODOX. Hemolytic assay revealed exceptional hemocompatibility of the entire nanocarrier. The APO encapsulation mechanism ensures applicability using a wide variety of chemotherapeutic drugs, and the presented surface modification enables targeting to various tumors.