Novel Additive Manufactured Multielectrode Electrochemical Cell with Honeycomb Inspired Design for the Detection of Methyl Parathion in Honey Samples.

The development and increase in the number of crops recently have led to the requirement for greater efficiency in world food production and greater consumption of pesticides. In this context, the widespread use of pesticides has affected the decrease in the population of pollinating insects and has caused food contamination. Therefore, simple, low-cost, and quick analytical methods can be interesting alternatives for checking the quality of foods such as honey.

Low-cost, facile droplet modification of screen-printed arrays for internally validated electrochemical detection of serum procalcitonin.

This manuscript presents the design and facile production of screen-printed arrays (SPAs) for the internally validated determination of raised levels of serum procalcitonin (PCT). The screen-printing methodology produced SPAs with six individual working electrodes that exhibit an inter-array reproducibility of 3.64% and 5.

Flexible Label-Free Platinum and Bio-PET-Based Immunosensor for the Detection of SARS-CoV-2.

The demand for new devices that enable the detection of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) at a relatively low cost and that are fast and feasible to be used as point-of-care is required overtime on a large scale. In this sense, the use of sustainable materials, for example, the bio-based poly (ethylene terephthalate) (Bio-PET) can be an alternative to current standard diagnostics. In this work, we present a flexible disposable printed electrode based on a platinum thin film on Bio-PET as a substrate for the development of a sensor and immunosensor for the monitoring of COVID-19 biomarkers, by the detection of L-cysteine and the SARS-CoV-2 spike protein, respectively.

Novel and highly stable strategy for the development of microfluidic enzymatic assays based on the immobilization of horseradish peroxidase (HRP) into cotton threads.

The use of biological components in the development of new methods of analysis and point-of-care (POC) devices is an ever-expanding theme in analytical chemistry research, due to the immense potential for early diagnosis of diseases and monitoring of biomarkers. In the present work, the evaluation of an electrochemical microfluidic device based on the immobilization of horseradish peroxidase (HRP) enzyme into chemically treated cotton threads is described. This bioreactor was used as a channel for the build of the microfluidic device, which has allowed to use of a non-modified screen-printed electrode (SPE) as an amperometric detector.

Influence of filament aging and conductive additive in 3D printed sensors.

3D printing technology combined with electrochemical techniques have allowed the development of versatile and low-cost devices. However, some aspects need to be considered for the good quality and useful life of the sensors. In this work, we have demonstrated herein that the filament aging, the conductive material, and the activation processes (post-treatments) can influence the surface characteristics and the electrochemical performance of the 3D printed sensors.

Biosensing strategies for the electrochemical detection of viruses and viral diseases - A review.

Viruses are the causing agents for many relevant diseases, including influenza, Ebola, HIV/AIDS, and COVID-19. Its rapid replication and high transmissibility can lead to serious consequences not only to the individual but also to collective health, causing deep economic impacts. In this scenario, diagnosis tools are of significant importance, allowing the rapid, precise, and low-cost testing of a substantial number of individuals.

Sensing of L-methionine in biological samples through fully 3D-printed electrodes.

The variation in biomarkers levels, such as L-methionine, can be an indicator of health problems or diseases, such as metabolism, neuropsychiatric disorders, or some virus infections. Thus, the development of accurate sensors, with low-cost and rapid response has been gaining increasing importance and attractiveness for the early diagnosis of diseases. In this regard, we have proposed a method for L-methionine electrochemical detection using a low-cost and simple arrangement of 3D-printed electrodes (working, reference, and auxiliary electrodes) based on polylactic acid/graphene filament (PLA-G), in which all electrodes were printed.

A carbon fiber ultramicroelectrode as a simple tool to direct antioxidant estimation based on caffeic acid oxidation.

This work describes the construction and evaluation of carbon fiber ultramicroelectrodes (CF-UMEs) in the voltammetric estimation of the antioxidant capacity of wine and grape samples based on caffeic acid (HCAF) oxidation. For this, lab-made CF-UMEs were constructed using an arrangement of six carbon fibers (7 μm diameters individual) assembled in a glass capillary, and caffeic acid (HCAF) was used as a standard solution. By using the most straightforward 2-electrode cell arrangement (the CF-UME as a working electrode and Ag/AgCl as a reference/auxiliary electrode), voltammetric measurements of a 1.

Epidemiology of Megninia spp. in laying flocks from the State of Minas Gerais, Brazil.

Aspects related to the epidemiology of Megninia ginglymura were studied, in order to determine predisposing factors for the occurrence in layer chicken houses of commercial farms in the State of Minas Gerais, Brazil. An observational, cross-sectional, analytical survey was conducted for identifying major risks or protection factors for infestations. Four hundred thirty-one houses located in forty-three farms were visited in 2012.

An electroanalytical approach for evaluation of biochar adsorption characteristics and its application for lead and cadmium determination.

This work describes for first time the use of electroanalytical techniques for evaluation of adsorptive proprieties of biochar using it as electrode modifier and its application for preconcentration and determination of Lead(II) and Cadmium(II) under differential pulse adsorptive voltammetric conditions (DPAdSV). Samples of biochars were obtained from castor oil cake using a predefined set of experimental conditions varying the heating rate (V), final temperature (T) and warm-up period (P) and subsequently used for carbon paste modified electrode (CPME) preparation. The proposed method was applied for Lead(II) and Cadmium(II) determination in spiked simulated industrial effluents and the limit of detection obtained for both metals were adequated for determination of these evaluated ions taking into account the limits established by Brazilian legislation.

Quill mites in Brazilian psittacine birds (Aves: Psittaciformes).

The primary and secondary feathers of 170 Brazilian psittacine birds (Aves: Psittaciformes) were examined in order to identify feather quill mite fauna. Birds were held captive in two locations in the state of Minas Gerais (MG), and two in the state of Espirito Santo (ES). The quills were cut longitudinally and were examined under optical microscopy.

Principal component analysis on the perceptions of milk producers about Rhipicephalus (Boophilus) microplus control in Minas Gerais.

Milk producers in Lavras, Passos and Divinópolis, Minas Gerais, were interviewed with the aim of evaluating their perceptions and attitudes regarding control over Rhipicephalus (Boophilus) microplus. Multivariate correlation between the variables was done by means of principal component analysis. The producers' perceptions and attitudes regarding R.

Hepatozoon spp. (Apicomplexa: Hepatozoidae) infection and selected hematological values of the neotropical rattlesnake, Crotalus durissus collilineatus (Linnaeus, 1758) (Serpentes: Viperidae), from Brazil.

This study aims to establish the hematological values of Crotalus durissus collilineatus snakes captured in Brazil as well as to verify the effects of hematozoan infection on these snakes. Eighty-three blood samples were drawn from C. d.

Amblyomma rotundatum (Koch, 1844) (Acari: Ixodidae) two-host life-cycle on Viperidae snakes.

Amblyomma rotundatum is an ixodid tick that infests ectothermic animals and reproduces exclusively by parthenogenesis. This tick has been frequently reported to infest reptiles and amphibians, under natural conditions and sometimes in captivity. It was described in Brazil and several other countries of South, Central and North America.

Salivary immunoglobulin a response to a match in top-level brazilian soccer players.

It has been suggested that several parameters of mucosal immunity, including salivary immunoglobulin A (s-IgA), are affected by heavy exercise either in field sports or in the laboratory environment. Few observations have been made during a true sporting environment, particularly in professional soccer. We tested the hypothesis that salivary IgA levels will be decreased after a 70-minute regulation in a top-level professional soccer friendly match.

The impact of a 17-day training period for an international championship on mucosal immune parameters in top-level basketball players and staff members.

This investigation examined the impact of a 17-d training period (that included basketball-specific training, sprints, intermittent running exercises, and weight training, prior to an international championship competition) on salivary immunoglobulin A (SIgA) levels in 10 subjects (athletes and staff members) from a national basketball team, as a biomarker for mucosal immune defence. Unstimulated saliva samples were collected at rest at the beginning of the preparation for the Pan American Games and 1 d before the first game. The recovery interval from the last bout of exercise was 4 h.

[Water quality evaluation in rural areas of Lavras, Minas Gerais, Brazil, 1999-2000].

In addition to personal interviews, laboratory analyses were performed using 80 water samples from 45 rural areas that are crossed by the Agua Limpa and Santa Cruz streams close to the city of Lavras, southern Minas Gerais State. The results allowed comparing the quality of water used for agriculture and the identification of determinant factors. The Agua Limpa stream mostly crosses an area used primarily for housing and characterized by low schooling.

Biology of Amblyomma aureolatum (Pallas, 1772) (Acari: Ixodidae) on some laboratory hosts in Brazil.

The ixodid Amblyomma aureolatum is suspected to play a role in the epidemiology of wild life-cycle hemoparasites, which frequently infect dogs in rural and hunting areas in Brazil. Little is known about its bionomics. The objective of the present study was to evaluate some bionomic aspects of A.