Antimicrob Agents Chemother
December 2024
The pipeline for new drugs against multidrug-resistant remains limited, highlighting the urgent need for innovative treatments. New strategies, such as membrane-targeting molecules acting as adjuvants, aim to enhance antibiotic effectiveness and combat resistance. RW01, a cyclic peptide with low antimicrobial activity, was selected as an adjuvant to enhance drug efficacy through membrane permeabilization.
View Article and Find Full Text PDFAntibiotic resistance is one of the most important concerns in global health today. A growing number of infections are becoming harder to treat with conventional drugs and fewer new antibiotics are being developed. In this context, strategies based on blocking or attenuating virulence pathways that do not focus on eradication of bacteria are potential therapeutic approaches that should reduce the selective pressure exerted on the pathogen.
View Article and Find Full Text PDFMore than 70% of bacteria are resistant to all or nearly all known antimicrobials, creating the need for the development of new types of antimicrobials or the use of "last-line" antimicrobial therapies for the treatment of multi-resistant bacteria. These antibiotics include Glycopeptide (Vancomycin), Polymyxin (Colistin), Lipopeptide (Daptomycin), and Carbapenem (Meropenem). However, due to the toxicity of these types of molecules, it is necessary to develop new rapid methodologies to be used in Therapeutic Drug Monitoring (TDM).
View Article and Find Full Text PDFDetecting sputum pyocyanin (PYO) with a competitive immunoassay is a promising approach for diagnosing Pseudomonas aeruginosa respiratory infections. However, it is not possible to perform a negative control to evaluate matrix-effects in competitive immunoassays, and the highly complex sputum matrix often interferes with target detection. Here, we show that these issues are alleviated by performing competitive immunoassays with a paper biosensor.
View Article and Find Full Text PDFSARS-CoV-2, a positive-strand RNA virus has caused devastating effects. The standard method for COVID diagnosis is based on polymerase chain reaction (PCR). The method needs expensive reagents and equipment and well-trained personnel and takes a few hours to be completed.
View Article and Find Full Text PDFConsidering the complexities and speed of modern food chains, there is an increasing demand for point-of-need detection of food contaminants, particularly highly regulated chemicals and carcinogens such as aflatoxin B1. We report a user-friendly smartphone-based magneto-immunosensor on carbon black modified electrodes for point-of-need detection of aflatoxin B1 in cereals. For buffered analyte solutions and a corn extract sample, the assay demonstrated a low limit of detection of 13 and 24 pg/mL, respectively.
View Article and Find Full Text PDFMicrobiol Spectr
August 2022
Understanding quorum sensing (QS) and its role in the development of pathogenesis may provide new avenues for diagnosing, surveillance, and treatment of infectious diseases. For this purpose, the availability of reliable and efficient analytical diagnostic tools suitable to specifically detect and quantify these essential QS small molecules and QS regulated virulence factors is crucial. Here, we reported the development and evaluation of antibodies and an enzyme-linked immunosorbent assay (ELISA) for HQNO (2-heptyl-4-quinoline N-oxide), a QS product of the PqsR system, which has been found to act as a major virulence factor that interferes with the growth of other microorganisms.
View Article and Find Full Text PDFThe development of a proof-of-concept point-of-care (PoC) device for the determination of oral anticoagulants determination is presented. Acenocoumarol (ACL) is prescribed to prevent certain cardiovascular diseases related to the prevention of deep vein thrombosis, pulmonary embolism, myocardial infarction, and stroke. Oral anticoagualant treatment (OAT) represents a population of 2% under treatment which has expenditures about $ 144 million in 2011.
View Article and Find Full Text PDFStandard methods for chemical food safety testing in official laboratories rely largely on liquid or gas chromatography coupled with mass spectrometry. Although these methods are considered the gold standard for quantitative confirmatory analysis, they require sampling, transferring the samples to a central laboratory to be tested by highly trained personnel, and the use of expensive equipment. Therefore, there is an increasing demand for portable and handheld devices to provide rapid, efficient, and on-site screening of food contaminants.
View Article and Find Full Text PDFQuorum sensing (QS) is a sophisticated bacterial communication system which plays a key role in the virulence and biofilm formation of many pathogens. The Pseudomonas aeruginosa QS network consists of four sets of connected systems (las, rlh, pqs and iqs) hierarchically organized. The pqs system involves characteristic autoinducers (AI), most of them sharing an alkylquinolone (AQ) structure, and is able to carry out several relevant biological functions besides its main signalling activity.
View Article and Find Full Text PDFQuorum sensing (QS) is a bacterial cell density-based communication system using low molecular weight signals called autoinducers (AIs). Identification and quantification of these molecules could provide valuable information related to the stage of colonization or infection as well as the stage of the disease. With this scenario, we report here for the first time the development of antibodies against the PQS (pseudomonas quinolone signal), the main signaling molecule from the QS system of , and the development of a microplate-based enzyme-linked immunosorbent assay (ELISA) able of quantifying this molecule in complex biological media in the low nanometer range (LOD, 0.
View Article and Find Full Text PDFAn immunoassay was developed that utilized plasmonic coupling between immobilised gold nanorods and colloid gold nanospheres to detect the marine toxin domoic acid (DA). The aspect ratio of the nanorods was optimised and the effects of variation in acidity, silver to gold ratio, cetyltrimethylammonium bromide (CTAB) concentration and seed addition in the growth solution on the yield, size variance and LSPR peak position was investigated. Excellent nanorods (size variation < 15%; aspect ratio 3.
View Article and Find Full Text PDFAlzheimer's disease (AD) is a neurodegenerative disorder, characterized by a functional deterioration of the brain. Currently, there are selected biomarkers for its diagnosis in cerebrospinal fluid. However, its extraction has several disadvantages for the patient.
View Article and Find Full Text PDFBacterial quorum sensing (QS) is being contemplated as a promising target for developing innovative diagnostic and therapeutic strategies. Here we report for the first time the development of antibodies against 2-heptyl-4-quinolone (HHQ), a signaling molecule from the QS system of , involved in the production of important virulent factors and biofilm formation. The antibodies produced were used to develop an immunochemical diagnostic approach to assess the potential of this molecule as a biomarker of infection.
View Article and Find Full Text PDFEnvironmental pollutants vigilance is one of the main problems that the aquaculture industry has to face with the objective to ensure the quality of their products and prevent entrance in the food chain that finally may arrive to the consumer. Contaminants such as hormones, antibiotics or biocides are especially relevant due to their toxicity, pharmacological effect or hormonal activity that can be considered harmful for the final consumer. The contaminants can be detected in the environment where the food is growing, and their concentration can be found (i.
View Article and Find Full Text PDFBrain natriuretic peptides (BNPs) are well-established cardiovascular disease (CVD) biomarkers that are released from the heart after ventricular wall stress. Particularly, the N-terminal proBNP (NT-proBNP) is a 76 aa long peptide and is recognized as an indicator for the diagnosis of heart failure (HF) and is being used in routine tests in emergency rooms when levels are above 0.4 ng mL.
View Article and Find Full Text PDFInfectious diseases are still a worldwide important problem. This fact has led to the characterization of new biomarkers that would allow an early, fast and reliable diagnostic and targeted therapy. In this context, Pseudomonas aeruginosa can be considered one of the most threatening pathogens since it causes a wide range of infections, mainly in patients that suffer other diseases.
View Article and Find Full Text PDFThe fluorescence-based detection of biological complexes on solid substrates is widely used in microarrays and lateral flow tests. Here, we investigate thiol-ene micropillar scaffold sheets ("synthetic paper") as the solid substrate in such assays. Compared to state-of-the-art glass and nitrocellulose substrates, assays on synthetic paper provide a stronger fluorescence signal, similar or better reproducibility, lower limit of detection (LOD), and the possibility of working with lower immunoreagent concentrations.
View Article and Find Full Text PDFIn this work, we report the development of a highly sensitive biosensor for sulfapyridine detection based on an integrated bio micro-electromechanical system (Bio-MEMS) containing four gold working electrodes (WEs), a platinum counter electrode (CE), and a reference electrode (RE). Firstly, the cleaned WEs were modified with 4-aminophenylacetic acid (CMA). Then, (5-[4-(amino)phenylsulfonamide]-5-oxopentanoic acid (SA2BSA) was immobilized onto the transducers surface by carbodiimide chemistry.
View Article and Find Full Text PDFKynurenic acid (KYNA) is a product of the tryptophan (TRP) metabolism via the kynurenine pathway (KP). This pathway is activated in neurodegenerative disorders, such as Alzheimer´s disease (AD). KYNA is primarily produced by astrocytes and is considered neuroprotective.
View Article and Find Full Text PDFGold nanostars (GNST), gold nanospheres (GNP) and carbon black (CB) are chosen as alternative nanomaterials to modify carbon screen-printed electrodes (c-SPEs). The resulting three kinds of modified c-SPEs (GNP-SPE, CB-SPE and GNSP-SPE) were electrochemically and microscopically characterized and compared with standardized c-SPEs after pretreatment with phosphate buffer by pre-anodization (pre-SPE). The results show outstanding electrochemical performance of the carbon black-modified SPEs which show low transient current, low capacitance and good porosity.
View Article and Find Full Text PDFPersonalized medicine is pushing forward new diagnostic techniques to aid in controlling drug therapeutic levels and their toxic effects. This study aims to develop a high-throughput screening method for therapeutic drug monitoring (TDM) and occupational exposure of cyclophosphamide (CP), an alkylating agent used as a chemotherapeutic and immunosuppressive drug. In order to achieve this goal, an immunizing hapten that exposes the cyclophosphamide moiety has been designed for the first time.
View Article and Find Full Text PDFFive different enzyme-linked immunosorbent assays (ELISAs) have been developed and applied for the detection of five representatives of important families of chemical pollutants in seawater: Irgarol 1051® (triazine biocide), sulfapyridine and chloramphenicol (antibiotics), 17β-estradiol (hormone), and domoic acid (algae toxin). The assays were validated by high-performance liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (HRMS) showing good correlation between both immunochemical and chemical techniques. A process of extraction and clean-up was added prior to the analysis based on solid-phase extraction (SPE).
View Article and Find Full Text PDFAnal Bioanal Chem
March 2019
Nanobodies (Nbs) have arisen as an alternative to conventional antibodies (Abs) and show great potential when used as tools in different biotechnology fields such as diagnostics and therapy. Different approaches have been described for the production of Nbs and these methods face new challenges focused on improving yield, affinity, and reducing production costs. This review summarizes these challenges, and also the latest advances in the detection of different kinds of molecules, such as proteins and small molecules, and describes their potential use for noninvasive in vivo imaging and for in vitro assays.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
January 2019
Nanomaterials have been the focus of attention in several fields, including biomedicine, electronics, or catalysis, mainly due to the novel properties of the materials at the nanoscale. In the field of diagnosis, nanomaterials have been contemplated as an opportunity to improve sensitivity and time of response, therefore, facilitating early treatment and monitoring of the disease. For therapeutic applications, new drug delivery nanosystems aiming to provide enhanced efficiency have been proposed often addressing selective or controlled delivery of therapeutic agents to particular cells to maximize treatment efficacy minimizing adverse effects.
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