Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
CVIR Endovasc ; 7(1): 38, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641706

RESUMO

BACKGROUND: Endovascular techniques are advancing with the change of treatment paradigm for abdominal aortic aneurysms. Fenestrated EVAR (fEVAR) and branched EVAR (bEVAR) are used for complex aortic aneurysm repair. Both fEVAR and bEVAR have their own advantages and disadvantages. Semi-branches are a new feature that attempt to combine the advantages of both fEVAR and bEVAR. TECHNIQUE: We describe the use of a 4-vessel semi-branched EVAR in a failed EVAR case with a type 1a endoleak. CONCLUSION: The novel feature of semi-branches in custom-made EVAR devices in endovascular aortic treatment following failed EVAR appear to be a feasible option.

2.
Sensors (Basel) ; 24(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38544223

RESUMO

Colorimetric characterisation systems based on LEDs and RBG sensors are straightforward to implement, are highly integrable allowing for portable measurement systems and can be constructed using widespread and affordable components. They have already proved to be a satisfactory solution in several applications related to chemical analysis. In this paper, we present an RGB sensor-based prototype for colorimetric characterisation, which can accommodate cuvettes with optical paths of 10 mm and 40 mm. We assessed the impact of experimental condition parameters such as the variability of the analyte volume in the cuvette, as well as the presence of floating particles or deposits at the bottom of the cuvette. While these would not impact the result given by a spectrophotometer that generally has a directional light source, they must be considered in LED/RGB sensor analysers in which the light path is not tightly controlled. We demonstrated that there is a minimal sensor height above the bottom of the cuvette and a minimal analyte level (both depending on the prototype optical path length) above which the analyte volume and the presence of floating particles and deposits have no impact on the prototype output signal. Finally, based on these results, we proposed a test method for a quick dye-displacement assay, in which the reagent is a dye-loaded molecularly imprinted polymer that is poured directly into a cuvette.

3.
PLoS Negl Trop Dis ; 17(8): e0011535, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37540724

RESUMO

Endemic in Brazil, visceral leishmaniasis (VL) is a zoonotic infection that is among the most important parasitic diseases transmitted by vectors. Dogs are the main reservoirs of canine leishmaniasis (CanL) and their identification is used in some countries as part of disease prevention and control measures in the canine and human population. In this context, serological tests are necessary, composed of antigens capable of correctly identifying infected dogs, minimizing the number of false-negative cases. This study aimed to identify more immunoreactive peptides derived from two previously described whole proteins (rDyn-1 and rKDDR-plus) and compare their performance to the control antigens rK39 and the crude extract for the detection of dogs infected with L. infantum, especially the asymptomatic ones. The three selected peptides and a mixture of them, along with the rDyn-1, rKDDR-plus, rK39, and crude extract antigens were evaluated using indirect ELISA with sera samples from 186 dogs with CanL, being asymptomatic (n = 50), symptomatic (n = 50), co-infected (n = 19), infected with Babesia sp. (n = 7), Ehrlichia sp. (n = 6), T. cruzi (n = 20) and uninfected (n = 34). The results showed that the rDyn-1 protein and the peptide mixture had the highest sensitivity (100% and 98.32%, respectively) and specificity (97.01 and 98.51, respectively). A high degree of kappa agreement was found for rDyn-1 protein (0.977), mixed peptides (0.965), rKDDR-plus protein (0.953), K-plus peptide 1 (0.930) and Dyn-1 peptide (0.893). The mixture of peptides showed the highest likelihood (65.87). The ELISA using the mixture of peptides and the rDyn-1 protein showed high performance for CanL serodiagnosis. More mix combinations of the peptides and additional extended field tests with a larger sample size are recommended.


Assuntos
Doença de Chagas , Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Humanos , Cães , Animais , Antígenos de Protozoários , Sensibilidade e Especificidade , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Leishmaniose Visceral/epidemiologia , Peptídeos , Immunoblotting , Oligopeptídeos , Ensaio de Imunoadsorção Enzimática/métodos , Testes Sorológicos/métodos , Doenças do Cão/epidemiologia , Anticorpos Antiprotozoários
4.
EJNMMI Res ; 13(1): 42, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37171631

RESUMO

By clearing GABA from the synaptic cleft, GABA transporters (GATs) play an essential role in inhibitory neurotransmission. Consequently, in vivo visualization of GATs can be a valuable diagnostic tool and biomarker for various psychiatric and neurological disorders. Not surprisingly, in recent years several research attempts to develop a radioligand have been conducted, but so far none have led to suitable radioligands that allow imaging of GATs. Here, we provide an overview of the radioligands that were developed with a focus on GAT1, since this is the most abundant transporter and most of the research concerns this GAT subtype. Initially, we focus on the field of GAT1 inhibitors, after which we discuss the development of GAT1 radioligands based on these inhibitors. We hypothesize that the radioligands developed so far have been unsuccessful due to the zwitterionic nature of their nipecotic acid moiety. To overcome this problem, the use of non-classical GAT inhibitors as basis for GAT1 radioligands or the use of carboxylic acid bioisosteres may be considered. As the latter structural modification has already been used in the field of GAT1 inhibitors, this option seems particularly viable and could lead to the development of more successful GAT1 radioligands in the future.

5.
ACS Sens ; 8(1): 353-362, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36599088

RESUMO

Pseudomonas aeruginosa is a ubiquitous multi-drug-resistant bacterium, capable of causing serious illnesses and infections. This research focuses on the development of a thermal sensor for the indirect detection of P. aeruginosa infection using molecularly imprinted polymers (MIPs). This was achieved by developing MIPs for the detection of pyocyanin, the main toxin secreted by P. aeruginosa. To this end, phenazine was used as a dummy template, evaluating several polymeric compositions to achieve a selective MIP for pyocyanin recognition. The sensitivity of the synthesized MIPs was investigated by UV-vis analysis, with the best composition having a maximum rebinding capacity of 30 µmol g-1 and an imprinting factor (IF) of 1.59. Subsequently, the MIP particles were immobilized onto planar aluminum chips using an adhesive layer, to perform thermal resistance measurements at clinically relevant concentrations of pyocyanin (1.4-9.8 µM), achieving a limit of detection (LoD) of 0.347 ± 0.027 µM. The selectivity of the sensor was also scrutinized by subjecting the receptor to potential interferents. Furthermore, the rebinding was demonstrated in King's A medium, highlighting the potential of the sensor for the indirect detection of P. aeruginosa in complex fluids. The research culminates in the demonstration of the MIP-based sensor's applicability for clinical diagnosis. To achieve this goal, an experiment was performed in which the sensor was exposed to pyocyanin-spiked saliva samples, achieving a limit of detection of 0.569 ± 0.063 µM and demonstrating that this technology is suitable to detect the presence of the toxin even at the very first stage of its production.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Pseudomonas aeruginosa , Piocianina , Técnicas Eletroquímicas
6.
Acta Trop ; 239: 106827, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36610530

RESUMO

Visceral leishmaniasis (VL) is a fatal manifestation of an infection caused by intracellular protozoa of the Leishmania genus. In New World countries, VL is classified as a zoonotic disease with domestic dogs acting as its main reservoir. Asymptomatic dogs are as competent to transmit Leishmania to the vectors as symptomatic dogs, however current diagnostic tests are limited and present low sensitivity for this important group. The development of accurate tests is fundamental to the early diagnosis, treatment, and control of canine leishmaniasis. In this study, we investigated the use of a recombinant protein (dynamin-1-like protein, Dyn-1) from L. infantum, as a potential target antigen for leishmaniasis serodiagnosis in both symptomatic and asymptomatic dogs. The antigenic performance of the protein was evaluated by means of ELISA assays using sera from symptomatic (n = 25), asymptomatic (n = 34) and non-infected dogs (n = 36) using ELISA. In addition, sera from dogs experimentally infected with Trypanosoma cruzi (n = 49) and naturally infected with Babesia sp. (n = 8) were tested to evaluate possible cross-reactivity. A crude soluble antigen (CSA) of Leishmania was used as an antigen control and K39 and K26 were used as reference antigens because they are already widely used in commercial tests. rDyn-1-based assay showed the highest sensitivity (97%) compared to the antigens K39 (88%), K26 (86%) and crude extract (95%). The highest specificity among the tests was also obtained with the protein rDyn-1 (94%), compared with the other antigens K39 (81%), K26 (87%), and crude extract (77%). This study showed that the rDyn-1 ELISA assay was able to identify 100% of asymptomatic dogs, establishing its potential as a target for the diagnosis of canine leishmaniasis.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Cães , Leishmania infantum/genética , Dinamina I , Antígenos de Protozoários/genética , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Ensaio de Imunoadsorção Enzimática , Testes Sorológicos/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/parasitologia , Anticorpos Antiprotozoários , Sensibilidade e Especificidade
7.
Cardiovasc Intervent Radiol ; 46(2): 187-193, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36624291

RESUMO

PURPOSE: Iliac branch devices (IBD) are widely used to treat aortoiliac aneurysms with an unfit distal landing zone for standard endovascular aneurysm repair (EVAR). The aim of this retrospective study was to examine the treatment of aortoiliac aneurysms with the combination of the Endurant II(s) stent graft system (Medtronic®) and the E-liac stent graft (Artivion®). MATERIALS AND METHODS: Data of all patients who underwent an EVAR combined with unilateral or bilateral IBD between January 2015 and January 2020 were analyzed. Primary outcomes were technical success at implantation (successful EVAR with IBD extension placement and patency of the grafts without type 1 or type 3 endoleak), and type 1b/3 endoleak, hypogastric artery patency and IBD-related reinterventions during follow-up. Secondary outcomes were all type 1 endoleak, all reinterventions, rupture, and mortality during follow-up. RESULTS: A total of 38 patients were treated with a combination of EVAR with IBD. Technical success was 94.7% (n = 36/38). The 30-day survival was 100%. Median follow-up time was 31 months (range 8-56). During follow-up, no patients developed type 1b or type 3 endoleak and all hypogastric arteries at the side of IBD remained patent. The overall reintervention rate at 12 months follow-up was 5.3% (n = 2/38) and the IBD-related reintervention rate was 2.6% (n = 1/38). CONCLUSION: The combination of the Endurant II(s) and the E-liac stent graft system is an effective and safe procedure for patients with an aortoiliac aneurysm. We confirm the high hypogastric artery patency rate using IBD. Furthermore, these devices have a high technical success rate even when it is combined with an Endurant II(s) EVAR main body.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma Ilíaco , Humanos , Prótese Vascular/efeitos adversos , Endoleak/cirurgia , Implante de Prótese Vascular/efeitos adversos , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Stents/efeitos adversos , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Desenho de Prótese
8.
Food Chem ; 404(Pt B): 134653, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36327513

RESUMO

Accurate and fast on-site detection of harmful microorganisms in food products is a key preventive step to avoid food-borne illness and product recall. In this study, screen-printed electrodes (SPEs) were functionalized via a facile strategy with surface imprinted polymers (SIPs). The SIP-coated SPEs were used in combination with the heat transfer method (HTM) for the real-time detection of Escherichia coli. The sensor was tested in buffer, with a reproducible and sensitive response that attained a limit of detection of 180 CFU/mL. Furthermore, selectivity was assessed by analyzing the sensor's response to C. sakazakii, K. pneumoniae and S. aureus as analogue strains. Finally, the device was successfully used for the detection of E. coli in spiked milk as proof-of-application, requiring no additional sample preparation. These results suggest the proposed thermal biosensor possesses the potential of becoming a tool for routine, on-site monitoring of E. coli in food safety applications.


Assuntos
Técnicas Biossensoriais , Escherichia coli , Staphylococcus aureus , Eletrodos , Técnicas Biossensoriais/métodos , Laticínios , Limite de Detecção
9.
Sensors (Basel) ; 24(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38202993

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are a class of materials that have been widely used in the industrial production of a wide range of products. After decades of bioaccumulation in the environment, research has demonstrated that these compounds are toxic and potentially carcinogenic. Therefore, it is essential to map the extent of the problem to be able to remediate it properly in the next few decades. Current state-of-the-art detection platforms, however, are lab based and therefore too expensive and time-consuming for routine screening. Traditional biosensor tests based on, e.g., lateral flow assays may struggle with the low regulatory levels of PFAS (ng/mL), the complexity of environmental matrices and the presence of coexisting chemicals. Therefore, a lot of research effort has been directed towards the development of biomimetic receptors and their implementation into handheld, low-cost sensors. Numerous research groups have developed PFAS sensors based on molecularly imprinted polymers (MIPs), metal-organic frameworks (MOFs) or aptamers. In order to transform these research efforts into tangible devices and implement them into environmental applications, it is necessary to provide an overview of these research efforts. This review aims to provide this overview and critically compare several technologies to each other to provide a recommendation for the direction of future research efforts focused on the development of the next generation of biomimetic PFAS sensors.


Assuntos
Biomimética , Fluorocarbonos , Humanos , Carcinogênese , Carcinógenos , Indústrias
10.
Foods ; 11(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36141032

RESUMO

In recent years, melamine-sensing technologies have increasingly gained attention, mainly due to the misuse of the molecule as an adulterant in milk and other foods. Molecularly imprinted polymers (MIPs) are ideal candidates for the recognition of melamine in real-life samples. The prepared MIP particles were incorporated into a thermally conductive layer via micro-contact deposition and its response towards melamine was analyzed using the heat-transfer method (HTM). The sensor displayed an excellent selectivity when analyzing the thermal response to other chemicals commonly found in foods, and its applicability in food safety was demonstrated after evaluation in untreated milk samples, demonstrating a limit of detection of 6.02 µM. As the EU/US melamine legal limit in milk of 2.5 mg/kg falls within the linear range of the sensor, it can offer an innovative solution for routine screening of milk samples in order to detect adulteration with melamine. The results shown in this work thus demonstrate the great potential of a low-cost thermal platform for the detection of food adulteration in complex matrices.

11.
JAMA Netw Open ; 5(6): e2219372, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35767259

RESUMO

Importance: There has been a growing interest in the use of electronic noses (e-noses) in detecting volatile organic compounds in exhaled breath for the diagnosis of cancer. However, no systematic evaluation has been performed of the overall diagnostic accuracy and methodologic challenges of using e-noses for cancer detection in exhaled breath. Objective: To provide an overview of the diagnostic accuracy and methodologic challenges of using e-noses for the detection of cancer. Data Sources: An electronic search was performed in the PubMed and Embase databases (January 1, 2000, to July 1, 2021). Study Selection: Inclusion criteria were the following: (1) use of e-nose technology, (2) detection of cancer, and (3) analysis of exhaled breath. Exclusion criteria were (1) studies published before 2000; (2) studies not performed in humans; (3) studies not performed in adults; (4) studies that only analyzed biofluids; and (5) studies that exclusively used gas chromatography-mass spectrometry to analyze exhaled breath samples. Data Extraction and Synthesis: PRISMA guidelines were used for the identification, screening, eligibility, and selection process. Quality assessment was performed using Quality Assessment of Diagnostic Accuracy Studies 2. Generalized mixed-effects bivariate meta-analysis was performed. Main Outcomes and Measures: Main outcomes were sensitivity, specificity, and mean area under the receiver operating characteristic curve. Results: This review identified 52 articles with a total of 3677 patients with cancer. All studies were feasibility studies. The sensitivity of e-noses ranged from 48.3% to 95.8% and the specificity from 10.0% to 100.0%. Pooled analysis resulted in a mean (SE) area under the receiver operating characteristic curve of 94% (95% CI, 92%-96%), a sensitivity of 90% (95% CI, 88%-92%), and a specificity of 87% (95% CI, 81%-92%). Considerable heterogeneity existed among the studies because of differences in the selection of patients, endogenous and exogenous factors, and collection of exhaled breath. Conclusions and Relevance: Results of this review indicate that e-noses have a high diagnostic accuracy for the detection of cancer in exhaled breath. However, most studies were feasibility studies with small sample sizes, a lack of standardization, and a high risk of bias. The lack of standardization and reproducibility of e-nose research should be addressed in future research.


Assuntos
Nariz Eletrônico , Neoplasias , Adulto , Testes Respiratórios/métodos , Expiração , Humanos , Neoplasias/diagnóstico , Reprodutibilidade dos Testes
12.
ACS Sens ; 7(5): 1467-1475, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35537189

RESUMO

This work presents an imprinted polymer-based thermal biomimetic sensor for the detection of Escherichia coli. A novel and facile bacteria imprinting protocol for polydimethylsiloxane (PDMS) films was investigated, and these receptor layers were functionalized with graphene oxide (GO) in order to improve the overall sensitivity of the sensor. Upon the recognition and binding of the target to the densely imprinted polymers, a concentration-dependent measurable change in temperature was observed. The limit of detection attained for the sensor employing PDMS-GO imprints was 80 ± 10 CFU/mL, a full order lower than neat PDMS imprints (670 ± 140 CFU/mL), illustrating the beneficial effect of the dopant on the thermo-dynamical properties of the interfacial layer. A parallel benchmarking of the thermal sensor with a commercial impedance analyzer was performed in order to prove the possibility of using the developed PDMS-GO receptors with multiple readout platforms. Moreover, S. aureus, C. sakazakii and an additional E. coli strain were employed as analogue species for the assessment of the selectivity of the device. Finally, because of the potential that this biomimetic platform possesses as a low-cost, rapid, and on-site tool for monitoring E. coli contamination in food safety applications, spiked fruit juice was analyzed as a real sample. Reproducible and sensitive results fulfill the limit requirements of the applicable European microbiological regulation.


Assuntos
Impressão Molecular , Biomimética , Dimetilpolisiloxanos , Escherichia coli , Grafite , Impressão Molecular/métodos , Polímeros/química , Staphylococcus aureus
13.
ACS Sens ; 6(12): 4515-4525, 2021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34825565

RESUMO

Glucose bio-sensing technologies have received increasing attention in the last few decades, primarily due to the fundamental role that glucose metabolism plays in diseases (e.g., diabetes). Molecularly imprinted polymers (MIPs) could offer an alternative means of analysis to a field that is traditionally dominated by enzyme-based devices, posing superior chemical stability, cost-effectiveness, and ease of fabrication. Their integration into sensing devices as recognition elements has been extensively studied with different readout methods such as quartz-crystal microbalance or impedance spectroscopy. In this work, a dummy imprinting approach is introduced, describing the synthesis and optimization of a MIP toward the sensing of glucose. Integration of this polymer into a thermally conductive receptor layer was achieved by micro-contact deposition. In essence, the MIP particles are pressed into a polyvinyl chloride adhesive layer using a polydimethylsiloxane stamp. The prepared layer is then evaluated with the so-called heat-transfer method, allowing the determination of the specificity and the sensitivity of the receptor layer. Furthermore, the selectivity was assessed by analyzing the thermal response after infusion with increasing concentrations of different saccharide analogues in phosphate-buffered saline (PBS). The obtained results show a linear range of the sensor of 0.0194-0.3300 mM for the detection of glucose in PBS. Finally, a potential application of the sensor was demonstrated by exposing the receptor layer to increasing concentrations of glucose in human urine samples, demonstrating a linear range of 0.0444-0.3300 mM. The results obtained in this paper highlight the applicability of the sensor both in terms of non-invasive glucose monitoring and for the analysis of food samples.


Assuntos
Impressão Molecular , Glicemia , Automonitorização da Glicemia , Glucose , Humanos , Polímeros Molecularmente Impressos
14.
Biosensors (Basel) ; 11(10)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34677351

RESUMO

We demonstrate a novel way of creating three-dimensional microfluidic channels capable of following complex topographies. To this end, substrates with open channels and different geometries were 3D-printed, and the open channels were consecutively closed with a thermoplastic using a low-resolution vacuum-forming approach. This process allows the sealing of channels that are located on the surface of complex multiplanar topographies, as the thermoplastic aligns with the surface-shape (the macrostructure) of the substrate, while the microchannels remain mostly free of thermoplastic as their small channel size resists thermoplastic inflow. This new process was analyzed for its capability to consistently close different substrate geometries, which showed reliable sealing of angles >90°. Furthermore, the thermoplastic intrusion into channels of different widths was quantified, showing a linear effect of channel width and percentage of thermoplastic intrusion; ranging from 43.76% for large channels with 2 mm width to only 5.33% for channels with 500 µm channel width. The challenging sealing of substrate 'valleys', which are created when two large protrusions are adjacent to each other, was investigated and the correlation between protrusion distance and height is shown. Lastly, we present three application examples: a serpentine mixer with channels spun around a cuboid, increasing the usable surface area; a cuvette-inspired flow cell for a 2-MXP biosensor based on molecular imprinted polymers, fitting inside a standard UV/Vis-Spectrophotometer; and an adapter system that can be manufactured by one-sided injection molding and is self-sealed before usage. These examples demonstrate how this novel technology can be used to easily adapt microfluidic circuits for application in biosensor platforms.


Assuntos
Microfluídica , Tratamento de Ferimentos com Pressão Negativa , Polímeros , Impressão Tridimensional
15.
Polymers (Basel) ; 13(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34279364

RESUMO

The scope of the presented research orientates itself towards the development of a Molecularly Imprinted Polymer (MIP)-based dye displacement assay for the colorimetric detection of the antibiotic amoxicillin in aqueous medium. With this in mind, the initial development of an MIP capable of such a task sets focus on monolithic bulk polymerization to assess monomer/crosslinker combinations that have potential towards the binding of amoxicillin. The best performing composition (based on specificity and binding capacity) is utilized in the synthesis of MIP particles by emulsion polymerization, yielding particles that prove to be more homogenous in size and morphology compared to that of the crushed monolithic MIP, which is an essential trait when it comes to the accuracy of the resulting assay. The specificity and selectivity of the emulsion MIP proceeds to be highlighted, demonstrating a higher affinity towards amoxicillin compared to other compounds of the aminopenicillin class (ampicillin and cloxacillin). Conversion of the polymeric receptor is then undertaken, identifying a suitable dye for the displacement assay by means of binding experiments with malachite green, crystal violet, and mordant orange. Once identified, the optimal dye is then loaded onto the synthetic receptor, and the displaceability of the dye deduced by means of a dose response experiment. Alongside the sensitivity, the selectivity of the assay is scrutinized against cloxacillin and ampicillin. Yielding a dye displacement assay that can be used (semi-)quantitatively in a rapid manner.

16.
Biosensors (Basel) ; 11(2)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670184

RESUMO

Foodborne illnesses represent high costs worldwide in terms of medical care and productivity. To ensure safety along the food chain, technologies that help to monitor and improve food preservation have emerged in a multidisciplinary context. These technologies focus on the detection and/or removal of either biological (e.g., bacteria, virus, etc.) or chemical (e.g., drugs and pesticides) safety hazards. Imprinted polymers are synthetic receptors able of recognizing both chemical and biological contaminants. While numerous reviews have focused on the use of these robust materials in extraction and separation applications, little bibliography summarizes the research that has been performed on their coupling to sensing platforms for food safety. The aim of this work is therefore to fill this gap and highlight the multidisciplinary aspects involved in the application of imprinting technology in the whole value chain ranging from IP preparation to integrated sensor systems for the specific recognition and quantification of chemical and microbiological contaminants in food samples.


Assuntos
Impressão Molecular , Polímeros , Inocuidade dos Alimentos , Praguicidas , Receptores Artificiais
17.
J Chem Educ ; 98(2): 439-444, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33583951

RESUMO

The need to develop interest in STEM (science, technology, engineering, and mathematics) skills in young pupils has driven many educational systems to include STEM as a subject in primary schools. In this work, a science kit aimed at children from 8 to 14 years old is presented as a support platform for an innovative and stimulating approach to STEM learning. The peculiar design of the kit, based on modular components, is aimed to help develop a multitude of skills in the young students, dividing the learning process into two phases. During phase 1 the pupils build the experimental setup and visualize the scientific phenomena, while in phase 2, they are introduced and challenged to understand the principles on which these phenomena are based, guided by a handbook. This approach aims at making the experience more inclusive, stimulating the interest and passion of the pupils for scientific subjects.

18.
Molecules ; 25(22)2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182534

RESUMO

The rapid sensing of drug compounds has traditionally relied on antibodies, enzymes and electrochemical reactions. These technologies can frequently produce false positives/negatives and require specific conditions to operate. Akin to antibodies, molecularly imprinted polymers (MIPs) are a more robust synthetic alternative with the ability to bind a target molecule with an affinity comparable to that of its natural counterparts. With this in mind, the research presented in this article introduces a facile MIP-based dye displacement assay for the detection of (±) amphetamine in urine. The selective nature of MIPs coupled with a displaceable dye enables the resulting low-cost assay to rapidly produce a clear visual confirmation of a target's presence, offering huge commercial potential. The following manuscript characterizes the proposed assay, drawing attention to various facets of the sensor design and optimization. To this end, synthesis of a MIP tailored towards amphetamine is described, scrutinizing the composition and selectivity (ibuprofen, naproxen, 2-methoxphenidine, quetiapine) of the reported synthetic receptor. Dye selection for the development of the displacement assay follows, proceeded by optimization of the displacement process by investigating the time taken and the amount of MIP powder required for optimum displacement. An optimized dose-response curve is then presented, introducing (±) amphetamine hydrochloride (0.01-1 mg mL-1) to the engineered sensor and determining the limit of detection (LoD). The research culminates in the assay being used for the analysis of spiked urine samples (amphetamine, ibuprofen, naproxen, 2-methoxphenidine, quetiapine, bupropion, pheniramine, bromopheniramine) and evaluating its potential as a low-cost, rapid and selective method of analysis.


Assuntos
Anfetaminas/urina , Corantes/química , Polímeros Molecularmente Impressos , Polímeros/química , Detecção do Abuso de Substâncias/métodos , Urina/química , Anfetamina/urina , Bromofeniramina/urina , Bupropiona/urina , Relação Dose-Resposta a Droga , Técnicas Eletroquímicas , Reações Falso-Positivas , Humanos , Ibuprofeno/urina , Limite de Detecção , Impressão Molecular , Naproxeno/urina , Feniramina/urina , Piperidinas/urina , Pós , Fumarato de Quetiapina/urina
19.
Sens Actuators B Chem ; 325: 128973, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33012991

RESUMO

Molecularly imprinted polymers (MIPs) have emerged over the past few decades as interesting synthetic alternatives due to their long-term chemical and physical stability and low-cost synthesis procedure. They have been integrated into many sensing platforms and assay formats for the detection of various targets, ranging from small molecules to macromolecular entities such as pathogens and whole cells. Despite the advantages MIPs have over natural receptors in terms of commercialization, the striking success stories of biosensor applications such as the glucose meter or the self-test for pregnancy have not been matched by MIP-based sensor or detection kits yet. In this review, we zoom in on the commercial potential of MIP technology and aim to summarize the latest developments in their commercialization and integration into sensors and assays with high commercial potential. We will also analyze which bottlenecks are inflicting with commercialization and how recent advances in commercial MIP synthesis could overcome these obstacles in order for MIPs to truly achieve their commercial potential in the near future.

20.
Biosensors (Basel) ; 10(10)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987809

RESUMO

Point of care (PoC) diagnostics are at the focus of government initiatives, NGOs and fundamental research alike. In high-income countries, the hope is to streamline the diagnostic procedure, minimize costs and make healthcare processes more efficient and faster, which, in some cases, can be more a matter of convenience than necessity. However, in resource-limited settings such as low-income countries, PoC-diagnostics might be the only viable route, when the next laboratory is hours away. Therefore, it is especially important to focus research into novel diagnostics for these countries in order to alleviate suffering due to infectious disease. In this review, the current research describing the use of PoC diagnostics in resource-limited settings and the potential bottlenecks along the value chain that prevent their widespread application is summarized. To this end, we will look at literature that investigates different parts of the value chain, such as fundamental research and market economics, as well as actual use at healthcare providers. We aim to create an integrated picture of potential PoC barriers, from the first start of research at universities to patient treatment in the field. Results from the literature will be discussed with the aim to bring all important steps and aspects together in order to illustrate how effectively PoC is being used in low-income countries. In addition, we discuss what is needed to improve the situation further, in order to use this technology to its fullest advantage and avoid "leaks in the pipeline", when a promising device fails to take the next step of the valorization pathway and is abandoned.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Doenças Transmissíveis , Recursos em Saúde , Humanos , Monitorização Fisiológica , Testes Imediatos , Pobreza
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...