Carbon nanoparticle-based lateral flow assay for the detection of specific double-tagged DNA amplicons of Paracoccidioides spp.

To overcome the limitations of current methods for diagnosing paracoccidioidomycosis (PCM), it is critical to develop novel diagnostic strategies that can be implemented in low-resource settings and dramatically improve turnaround times. This study focused on the development of a portable molecular test to screen for Paracoccidioides spp. The proposed approach integrated double-tagging polymerase chain reaction (PCR) and a paper-based lateral flow assay (LFA) for readout, using carbon nanoparticles as a signal generation system.

Evaluating smartphone-based optical readouts for immunoassays in human and veterinary healthcare: A comparative study.

Recent advances have significantly enhanced the use of smartphone devices for medical diagnostics. This study uses high-resolution cameras in mobile devices to capture and process bioassay images, enabling the quantification of diverse biomarkers across a range of diagnostic tests conducted on 96-well microplates. The study evaluates the effectiveness of this technology through protein quantification techniques and immunoassays that generate colorimetric responses at specific wavelengths.

Peptide-based biosensing approaches for targeting breast cancer-derived exosomes.

Exosomes are nanovesicles present in all the biological fluids, making them attractive as non-invasive biomarkers for diseases like cancer, among many others. However, exosomes are complex to separate and detect, requiring comprehensive molecular characterization for their routine use in diagnostics. This study explores the use of peptides as cost-effective and stable alternatives to antibodies for exosome binding.

Improved biosensing of Legionella by integrating filtration and immunomagnetic separation of the bacteria retained in filters.

A novel approach is presented that combines filtration and the direct immunomagnetic separation of the retained bacteria Legionella in filters, for further electrochemical immunosensing. This strategy allows for the separation and preconcentration of the water-borne pathogen from high-volume samples, up to 1000 mL. The limit of detection of the electrochemical immunosensor resulted in 100 CFU mL and improved up to 0.

Magnetic Separation of Cell-Secreted Vesicles with Tailored Magnetic Particles and Downstream Applications.

The analysis of the receptors on the surface of the cell-secreted vesicles provides valuable information of the cell signature and may also offer diagnosis and/or prognosis of a wide range of diseases, including cancer.Due to their low concentration, conventional procedures for extracellular vesicle (EV) detection usually require relatively large sample volumes, involving preliminary purification or preconcentration steps from complex specimens. Here, we describe the separation and preconcentration in magnetic particles of extracellular vesicles obtained from cell culture supernatants from MCF7, MDA-MB-231, and SKBR3 breast cancer cell lines, human fetal osteoblastic cell line (hFOB), and human neuroblastoma SH-SY5Y cell line, as well as exosomes from human serum.

Extracellular vesicles, the emerging mirrors of brain physiopathology.

Extracellular vesicles are secreted by a wide variety of cells, and their primary functions include intercellular communication, immune responses, human reproduction, and synaptic plasticity. Their molecular cargo reflects the physiological processes that their cells of origin are undergoing. Thus, many studies have suggested that extracellular vesicles could be a promising biomarker tool for many diseases, mainly due to their biological relevance and easy accessibility to a broad range of body fluids.

Electrochemical Genosensing of Overexpressed GAPDH Transcripts in Breast Cancer Exosomes.

Exosomes are receiving highlighted attention as new biomarkers for the detection of cancer since they are profusely released by tumor cells in different biological fluids. In this paper, the exosomes are preconcentrated from the serum by immunomagnetic separation (IMS) based on a CD326 receptor as a specific epithelial cancer-related biomarker and detected by glyceraldehyde-3-phosphate dehydrogenase (GAPDH) transcripts. Following the lysis of the captured exosomes, the released GAPDH transcripts are amplified by reverse transcription polymerase chain reaction (RT-PCR) with a double-tagging set of primers on poly(dT)-modified-MPs to increase the sensitivity.

Advances in exosome analysis.

There is growing demand for novel biomarkers that detect early stage disease as well as monitor clinical management and therapeutic strategies. Exosome analysis could provide the next advance in attaining that goal. Exosomes are membrane encapsulated biologic nanometric-sized particles of endocytic origin which are released by all cell types.

A Sensitive Aptasensor Using Biotin-Streptavidin System for Patulin Detection in Apple Juice.

Patulin contamination in fruits, vegetables, and their products is considered a serious health risk factor for food safety and human health. Thus, a rapid, simple detection method for patulin is becoming important, which could provide a tool for routine screening and food surveys. The objective of this study was to develop a sensitive aptamer-based lateral flow assay (FLA) using Streptavidin functionalized gold nanoparticles for sensitive patulin detection.

The activity of alkaline phosphatase in breast cancer exosomes simplifies the biosensing design.

This work addresses a biosensor combining the immunomagnetic separation and the electrochemical biosensing based on the intrinsic ALP activity of the exosomes. This approach explores for the first time two different types of biomarkers on exosomes, in a unique biosensing device combining two different biorecognition reaction: immunological and enzymatic. Besides, the intrinsic activity of alkaline phosphatase (ALP) in exosomes as a potential biomarker of carcinogenesis as well as osseous metastatic invasion is also explored.

Immunomagnetic Separation Improves the Detection of Mycobacteria by Paper-Based Lateral and Vertical Flow Immunochromatographic Assays.

This work addresses a method that combines immunomagnetic separation (IMS) and paper-based nucleic acid immunochromatographic assay for the sensitive detection of In particular, the preconcentration of the bacteria was achieved by using magnetic particles modified with an antibody specific towards mycobacteria. Following the IMS, the bacteria were lysed, and the genome was amplified by double-tagging PCR, using a set of primers specific for the 16S rRNA gene for . During the amplification, the amplicons were labeled with biotin and digoxigenin tags.

Comparative Study of Gold and Carbon Nanoparticles in Nucleic Acid Lateral Flow Assay.

A lateral flow assay (LFA) is a paper-based, point-of-need test designed to detect a specific analyte in complex samples in low-resource settings. Although LFA has been successfully used in different applications, its use is still limited when high sensitivity is required, especially in the diagnosis of an early-stage condition. The limit of detection (LOD) is clearly related to the signal-generating system used to achieve the visual readout, in many cases involving nanoparticles coupled to a biomolecule, which, when combined, provides sensitivity and specificity, respectively.

Electrochemical Genosensing of Based on Padlock Probes and Rolling Circle Amplification.

Isothermal amplification techniques are emerging nowadays for the rapid and accurate detection of pathogenic bacteria in low resource settings, where many infectious diseases are endemic, and the lack of reliable power supply, trained personnel and specialized facilities pose critical barriers for timely diagnosis. This work addresses the detection of based on DNA isothermal amplification performed on magnetic particles (MPs) followed by electrochemical genosensing on disposable electrodes by square-wave voltammetry. In this approach, the bacterial DNA is preconcentrated using a target-specific magnetic probe and then amplified on the MPs by rolling circle amplification (RCA).

Assessment of the biological potential of diaryltriazene-derived triazene compounds.

In the present study, novel, 1,3-diaryltriazene-derived triazene compounds were synthesized and tested. Triazenes are versatile and belong to a group of alkylating agents with interesting physicochemical properties and proven biological activities. This study describes the synthesis, molecular and crystalline structure, biological activity evaluation, and antifungal and antimicrobial potentials of 1,3-bis(X-methoxy-Y-nitrophenyl)triazenes [X = 2 and 5; Y = 4 and 5].

Immunomagnetic Separation of Salmonella with Tailored Magnetic Micro- and Nanocarriers.

One of the main drawbacks in current methods for bacterium detection is their quantification at very low concentration level in complex specimens. Novel developments that are needed involve solid-phase preconcentration procedures which can be easily integrated with emerging technologies. Here, we describe the immunomagnetic separation (IMS) of Salmonella using magnetic carriers.

Multiplex detection and characterization of breast cancer exosomes by magneto-actuated immunoassay.

The exosomes are emerging as biomarkers for the detection of cancer in early stages, as well as for the follow-up of the patients under treatment. This paper describes the characterization of exosomes derived from three different breast cancer cell lines (MCF7, MDA-MB-231 and SKBR3), and the quantification based on a magneto-actuated immunoassay. The exosomes are separated and preconcentrated on magnetic particles by immunomagnetic separation and labelled with a second antibody conjugated with an enzyme for the optical readout performed with a standard microplate reader.

Biotinylated Phosphorus Dendrimers as Control Line in Nucleic Acid Lateral Flow Tests.

Lateral flow assays (LFA) are an affordable, easy-to-use, qualitative rapid test for clinical diagnosis in nonlaboratory environments and low-resource facilities. The control line of these tests is very important to provide a valid result, confirming that the platform operates correctly. A clear, nondiffused line is desirable.

Matrix Effect in the Isolation of Breast Cancer-Derived Nanovesicles by Immunomagnetic Separation and Electrochemical Immunosensing-A Comparative Study.

Exosomes are cell-derived nanovesicles released into biological fluids, which are involved in cell-to-cell communication. The analysis of the content and the surface of the exosomes allow conclusions about the cells they are originating from and the underlying condition, pathology or disease. Therefore, the exosomes are currently considered good candidates as biomarkers to improve the current methods for clinical diagnosis, including cancer.

Electrochemical immunosensing of nanovesicles as biomarkers for breast cancer.

Exosomes are nano-sized vesicles, which are currently under intensive study as potential diagnostic biomarkers for many health disorders, including cancer. This paper addresses the study of an electrochemical immunosensor in different formats for the characterization and quantification of exosomes derived from three breast cancer cell lines (MCF7, MDA-MB-231 and SKBR3). To achieve that, the exosomes were preconcentrated from cell-culture supernatant (and eventually in human serum) on magnetic particles modified with antibodies against the general tetraspanins CD9, CD63 and CD81, as well as specific receptors of cancer (CD24, CD44, CD54, CD326 and CD340).

Biomimetic magnetic sensor for electrochemical determination of scombrotoxin in fish.

This work addresses a novel, rapid and cost-effective approach for the electrochemical sensing of scombrotoxin (histamine) in fish based on magnetic molecularly imprinted polymer (magnetic-MIP). The histamine magnetic-MIP was synthesized by the core-shell method using histamine as a template, and 2-vinyl pyridine as functional monomer. The magnetic-MIP was characterized by TEM, SEM, and confocal microscopy.

Controlled degradability of PCL-ZnO nanofibrous scaffolds for bone tissue engineering and their antibacterial activity.

Up to date, tissue regeneration of large bone defects is a clinical challenge under exhaustive study. Nowadays, the most common clinical solutions concerning bone regeneration involve systems based on human or bovine tissues, which suffer from drawbacks like antigenicity, complex processing, low osteoinductivity, rapid resorption and minimal acceleration of tissue regeneration. This work thus addresses the development of nanofibrous synthetic scaffolds of polycaprolactone (PCL) - a long-term degradation polyester - compounded with hydroxyapatite (HA) and variable concentrations of ZnO as alternative solutions for accelerated bone tissue regeneration in applications requiring mid- and long-term resorption.

Electrochemical sensing of methyl parathion on magnetic molecularly imprinted polymer.

The electrochemical detection of methyl parathion in fish was performed by preconcentrating the pesticide on magnetic molecularly imprinted polymer and further readout on magneto-actuated electrode by square wave voltammetry. The magnetic molecularly imprinted polymer was synthesized by a magnetic core-shell strategy, using methacrylic acid as a functional monomer, and selected by theoretical calculation using the density functional theory (DFT). The characterization of this material was performed by SEM, TEM and XRD.

Biotransformation of disperse dyes using nitroreductase immobilized on magnetic particles modified with tosyl group: Identification of products by LC-MS-MS and theoretical studies conducted with DNA.

The present work evaluates the action of nitroreductase enzyme immobilized on Tosylactivated magnetic particles (MP-Tosyl) on three disperse dyes which contain nitro and azo groups. The dyes included Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). The use of a magnet enabled the rapid and easy removal of the immobilized enzyme after biotransformation; this facilitated the identification of the products generated using high-performance liquid chromatography with diode array detector (HPLC-DAD) and mass spectrometry (LC-MS/MS).

Interferon gamma transcript detection on T cells based on magnetic actuation and multiplex double-tagging electrochemical genosensing.

Interferon-γ is a proinflammatory cytokine, and its production is related with effective host defense against intracellular pathogens. Therefore, the level of interferon-γ is considered a good biomarker for intracellular infections. It is also useful for the assessment, treatment progression and follow-up of non-communicable diseases, including cancer and autoimmune disorders, among others.