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1.
Biomed Microdevices ; 26(2): 21, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558326

RESUMO

Kirigami is one of the interesting paper art forms and the modified sub-class of origami. Kirigami paper art is widely employed in a variety of applications, and it is currently being used in biosensors because of its outstanding advantages. This is the first study on the use of a Kirigami-based aptasensor for DENV (Dengue virus)-antigen detection. In this study, the kirigami approach has been utilized to develop a stretchable, movable, and flexible sensor. The constructed stretchable-kirigami electrode helps in adjusting the connection of electrodes without disturbing the electrochemical cell zone during the experiment. To increase the sensitivity of this biosensor we have synthesized Ag-NPs (Silver nanoparticles) via chemical methods and characterized their results with the help of TEM & UV-Vis Spectroscopy. Different electrochemical approaches were used to validate the sensor response i.e., CV (Cyclic voltammetry) and LSV (Linear sweep voltammetry), which exhibited great detection capability towards dengue virus with the range of 0.1 µg/ml to 1000 µg/ml along with a detection limit of 0.1 µg/ml and showing no reactivity to the chikungunya virus antigen, making it more specific to the DENV antigen. Serum (healthy-human) was also successfully applied to validate the results of the constructed aptasensor. Integration of the Kirigami approach form with the electrochemical aptasensor that utilizes a 3-E setup (three-electrode setup) which is referred to as a tripod and collectively called Kirigami-tripod-based aptasensor. Thus, the developed integrated platform improves the sensors capabilities in terms of cost efficiency, high stretchability, and sensitivity.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Dengue , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Aptâmeros de Nucleotídeos/química , Ouro/química , Prata/química , Técnicas Biossensoriais/métodos , Eletrodos , Dengue/diagnóstico , Limite de Detecção
2.
Sensors (Basel) ; 24(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38339518

RESUMO

There is currently a lot of interest in the construction of point-of-care devices stemming from paper-based origami biosensors. These devices demonstrate how paper's foldability permits the construction of sensitive, selective, user-friendly, intelligent, and maintainable analytical devices for the detection of several ailments. Herein, the first example of the electrochemical aptasensor-based polyvalent dengue viral antigen detection using the origami paper-folding method is presented. Coupling it with an aptamer leads to the development of a new notation known as OBAs, or origami-based aptasensor, that presents a multitude of advantages to the developed platform, such as assisting in safeguarding the sample from air-dust particles, providing confidentiality, and providing a closed chamber to the electrodes. In this paper, gold-decorated nanocomposites of zinc and graphene oxide (Au/ZnO/GO) were synthesized via the chemical method, and characterization was conducted by Scanning Electron Microscope, Transmission Electron Microscope, UV-Vis, and XRD which reveals the successful formation of nanocomposites, mainly helping to enhance the signal and specificity of the sensor by employing aptamers, since isolation and purification procedures are not required. The biosensor that is being demonstrated here is affordable, simple, and efficient. The reported biosensor is an OBA detection of polyvalent antigens of the dengue virus in human serum, presenting a good range from 0.0001 to 0.1 mg/mL with a limit of detection of 0.0001 mg/mL. The reported single-folding ori-aptasensor demonstrates exceptional sensitivity, specificity, and performance in human serum assays, and can also be used for the POC testing of various viral infections in remote areas and underdeveloped countries, as well as being potentially effective during outbreaks. Highlights: (1) First report on origami-based aptasensors for the detection of polyvalent antigens of DENV; (2) In-house construction of low-cost origami-based setup; (3) Gold-decorated zinc/graphene nanocomposite characterization was confirmed via FESEM/UV-Vis/FTIR; (4) Cross-reactivity of dengue-aptamer has been deduced; (5) Electrochemical validation was conducted through CV.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Vírus da Dengue , Dengue , Grafite , Nanocompostos , Humanos , Técnicas Eletroquímicas/métodos , Grafite/química , Nanocompostos/química , Técnicas Biossensoriais/métodos , Dengue/diagnóstico , Ouro/química , Zinco , Aptâmeros de Nucleotídeos/química , Limite de Detecção
3.
Sensors (Basel) ; 23(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37420685

RESUMO

We present the development of an electrochemical paper-based analytical device (ePAD) for the detection of methamphetamine. Methamphetamine is a stimulant that young people use as an addictive narcotic, and it must be detected quickly since it may be hazardous. The suggested ePAD has the advantages of being simple, affordable, and recyclable. This ePAD was developed by immobilizing a methamphetamine-binding aptamer onto Ag-ZnO nanocomposite electrodes. The Ag-ZnO nanocomposites were synthesized via a chemical method and were further characterized via scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-vis spectrometry in terms of their size, shape, and colloidal activity. The developed sensor showed a limit of detection of about 0.1 µg/mL, with an optimum response time of about 25 s, and its extensive linear range was between 0.01 and 6 µg/mL. The application of the sensor was recognized by spiking different beverages with methamphetamine. The developed sensor has a shelf life of about 30 days. This cost-effective and portable platform might prove to be highly successful in forensic diagnostic applications and will benefit those who cannot afford expensive medical tests.


Assuntos
Metanfetamina , Nanocompostos , Óxido de Zinco , Humanos , Adolescente , Óxido de Zinco/química , Prata/química , Nanocompostos/química , Eletrodos , Técnicas Eletroquímicas/métodos
4.
Sensors (Basel) ; 22(11)2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35684847

RESUMO

Several illnesses that are chronic and acute are becoming more relevant as the world's aging population expands, and the medical sector is transforming rapidly, as a consequence of which the need for "point-of-care" (POC), identification/detection, and real time management of health issues that have been required for a long time are increasing. Biomarkers are biological markers that help to detect status of health or disease. Biosensors' applications are for screening for early detection, chronic disease treatment, health management, and well-being surveillance. Smart devices that allow continual monitoring of vital biomarkers for physiological health monitoring, medical diagnosis, and assessment are becoming increasingly widespread in a variety of applications, ranging from biomedical to healthcare systems of surveillance and monitoring. The term "smart" is used due to the ability of these devices to extract data with intelligence and in real time. Wearable, implantable, ingestible, and portable devices can all be considered smart devices; this is due to their ability of smart interpretation of data, through their smart sensors or biosensors and indicators. Wearable and portable devices have progressed more and more in the shape of various accessories, integrated clothes, and body attachments and inserts. Moreover, implantable and ingestible devices allow for the medical diagnosis and treatment of patients using tiny sensors and biomedical gadgets or devices have become available, thus increasing the quality and efficacy of medical treatments by a significant margin. This article summarizes the state of the art in portable, wearable, ingestible, and implantable devices for health status monitoring and disease management and their possible applications. It also identifies some new technologies that have the potential to contribute to the development of personalized care. Further, these devices are non-invasive in nature, providing information with accuracy and in given time, thus making these devices important for the future use of humanity.


Assuntos
Dispositivos Eletrônicos Vestíveis , Idoso , Biomarcadores , Gerenciamento Clínico , Nível de Saúde , Humanos , Monitorização Fisiológica
5.
Nanomedicine ; 33: 102350, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33359413

RESUMO

Infectious and hereditary diseases are the primary cause of human mortality globally. Applications of conventional techniques require significant improvement in sensitivity and specificity in therapeutics. However, clustered regularly interspaced short palindromic repeats (CRISPRs) is an innovative genome editing technology which has provided a significant therapeutic tool exhibiting high sensitivity, fast and precise investigation of distinct pathogens in an epidemic. CRISPR technology has also facilitated the understanding of the biology and therapeutic mechanism of cancer and several other hereditary diseases. Researchers have used the CRISPR technology as a theranostic approach for a wide range of diseases causing pathogens including distinct bacteria, viruses, fungi and parasites and genetic mutations as well. In this review article, besides various therapeutic applications of infectious and hereditary diseases we have also explained the structure and mechanism of CRISPR tools and role of CRISPR integrated biosensing technology in provoking diagnostic applications.


Assuntos
Terapia Genética/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Medicina de Precisão/métodos , Animais , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Doenças Transmissíveis , Fungos , Edição de Genes , Humanos , Mutação , Parasitos , Vírus
6.
Chem Eng J ; 414: 128759, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33551668

RESUMO

The recent outbreak of COVID-19 has created much inconvenience and fear that the virus can seriously affect humans, causing health hazards and death. This pandemic has created much worry and as per the report by World Health Organization (WHO), more than 43 million individuals in 215 countries and territories were affected. People around the world are still struggling to overcome the problems associated with this pandemic. Of all the available methods, reverse-transcriptase polymerase chain reaction (RT-PCR) has been widely practiced for the pandemic detection even though several diagnostic tools are available having varying accuracy and sensitivity. The method offers many advantages making it a life-saving tool, but the method has the limitation of transporting to the nearest pathology lab, thus limiting its application in resource limited settings. This has a risen a crucial need for point-of-care devices for on-site detection. In this venture, biosensors have been used, since they can be applied immediately at the point-of-care. This review will discuss about the available diagnostic methods and biosensors for COVID-19 detection.

7.
Sensors (Basel) ; 20(7)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272681

RESUMO

Norovirus is one of the leading causes of gastroenteritis, acute vomiting, intense diarrhoea, acute pain in the stomach, high fever, headaches, and body pain. Conventional methods of detection gave us very promising results but had disadvantages such as low sensitivity, cost ineffectiveness, reduced specificity and selectivity, etc. Therefore, biosensors can be a viable alternative device which can overcome all setbacks associated with the conventional method. An electrochemical sensor based on oxidized graphitic carbon nitride (Ox-g-C3N4) modified electrochemical paper-based analytical device (ePAD) was fabricated for the detection of norovirus DNA. The synthesized Ox-g-C3N4 nanosheets were characterized by field emission scanning electron microscopy (FESEM), X-ray Diffraction (XRD), UV-Vis spectroscopy and X-Ray Photoelectron Spectroscopy. The capture probe DNA (PDNA) modified electrodes were characterized by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). These two characterization techniques were also employed to find the optimal scan rate, response time and temperature of the fabricated sensor. The fabricated biosensor showed a limit of detection (LOD) of 100 fM. Furthermore, the specificity of the reported biosensor was affirmed by testing the response of capture probe DNA with oxidized graphitic carbon nitride (PDNA/Ox-g-C3N4) modified ePAD on the introduction of a non-complimentary DNA. The fabricated ePAD sensor is easy to fabricate, cost effective and specific, and requires a minimum analysis time of 5 s.


Assuntos
Técnicas Biossensoriais/métodos , Grafite/química , Compostos de Nitrogênio/química , Norovirus/genética , Papel , RNA Viral/análise , Técnicas Biossensoriais/instrumentação , Sondas de DNA/química , Sondas de DNA/metabolismo , Técnicas Eletroquímicas/métodos , Eletrodos , Ácidos Nucleicos Imobilizados/química , Ácidos Nucleicos Imobilizados/metabolismo , Limite de Detecção , Azul de Metileno/química , Nanoestruturas/química , Hibridização de Ácido Nucleico , RNA Viral/metabolismo
8.
Biomed Microdevices ; 22(1): 6, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31844990

RESUMO

Advancements in health care monitoring demand a rapid, accurate and reliable early diagnosis of "Heart Attack" (acute myocardial infarction) with an objective to develop a cost-effective, rapid and label-free point of care diagnostic test kit for the detection of cardiac troponin I (cTnI) on paper-based multi-frequency impedimetric transducers. Paper based sensing platforms were developed by integrating carboxyl group functionalized multi-walled carbon nanotubes (MWCNT) with antibodies of cardiac troponin I (anti-cTnI) biomarker and was characterized using Electrochemical Impedance Spectroscopy (EIS). Various concentrations of cTnI with anti cTnI were studied as a function of impedance change. The suitability of the proposed immunosensor is demonstrated by spiking cTnI in blood serum samples. The limit of detection (LoD) and sensitivity of the proposed sensor was determined to be 0.05 ng/mL and 1.85 mΩ/ng/mL respectively, with a response time of ~1 min. The shelf life of the fabricated sensor was nearly 30 days. The rapid response, very low detection limit, and cost effectiveness offer a portable platform to detect cTnI in blood serum samples. The proposed immunosensor, therefore, offers an affordable healthcare diagnostic platform in resource limited areas.


Assuntos
Imunoensaio/métodos , Miocárdio/metabolismo , Papel , Sistemas Automatizados de Assistência Junto ao Leito , Troponina I/análise , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Biomarcadores/análise , Biomarcadores/sangue , Impedância Elétrica , Eletroquímica , Eletrodos , Humanos , Limite de Detecção , Nanotubos de Carbono/química , Troponina I/sangue , Troponina I/metabolismo
9.
Bioprocess Biosyst Eng ; 42(6): 1077-1079, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30859339

RESUMO

The Figs. 2, 4 and 5 were published wrongly in this paper, due to inadvertent compilation of figures during uploading the paper.

10.
Bioprocess Biosyst Eng ; 40(4): 537-548, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27995333

RESUMO

Metformin (Mf) plays a major role in controlling insulin level of individuals at risk of developing diabetes mellitus. Overdose of Mf can cause lactic acidosis, diarrhoea, cough, or hoarseness, etc. These particulars point out the identification for selective and sensitive methods of Mf determination. In the present work, graphene nanoflakes-polymethylene blue (GNF-PMB) nano-composites were developed onto fluorine-doped tin oxide (SnO2/F) coated glass substrates for electrochemical sensing of Mf using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The developed sensor shows quick response time (10 s), linearity as 10-103 µM, LOD (0.1 nM), and good shelf life (10 weeks). Attempts have been made to utilize this electrode for estimation of Mf in urine samples. Configured as a highly responsive, reproducible Mf sensor, it combines the electrical properties of GNF and stable electron transfer of PMB. The newly developed Mf sensor presents a promising candidate in point-of-care diagnosis.


Assuntos
Espectroscopia Dielétrica/métodos , Grafite/química , Hipoglicemiantes/análise , Metformina/análise , Nanopartículas/química , Eletrodos , Humanos , Compostos de Estanho
11.
Analyst ; 140(6): 1988-94, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25674632

RESUMO

Determining the concentrations of acetylcholine (ACh) and choline (Ch) is clinically important. ACh is a neurotransmitter that acts as a key link in the communication between neurons in the spinal cord and in nerve skeletal junctions in vertebrates, and plays an important role in transmitting signals in the brain. A bienzymatic sensor for the detection of ACh was prepared by co-immobilizing choline oxidase (ChO) and acetylcholinesterase (AChE) on graphene matrix/platinum nanoparticles, and then electrodepositing them on an ITO-coated glass plate. Graphene nanoparticles were decorated with platinum nanoparticles and were electrodeposited on a modified ITO-coated glass plate to form a modified electrode. The modified electrode was characterized by scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) studies. The optimum response of the enzyme electrode was obtained at pH 7.0 and 35 °C. The response time of this ACh-sensing system was shown to be 4 s. The linear range of responses to ACh was 0.005-700 µM. This biosensor exhibits excellent anti-interferential abilities and good stability, retaining 50% of its original current even after 4 months. It has been applied for the detection of ACh levels in human serum samples.


Assuntos
Acetilcolina/sangue , Técnicas Biossensoriais/métodos , Grafite/química , Nanopartículas/química , Platina/química , Acetilcolina/metabolismo , Acetilcolinesterase/metabolismo , Alcaligenes/enzimologia , Oxirredutases do Álcool/metabolismo , Doença de Alzheimer/sangue , Animais , Espectroscopia Dielétrica/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Electrophorus , Enzimas Imobilizadas/metabolismo , Humanos , Limite de Detecção , Modelos Moleculares
12.
Bioprocess Biosyst Eng ; 38(5): 815-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25416586

RESUMO

A novel bionanocomposite, horse radish peroxidase- gold-nanoparticle-Calcium carbonate (HRP-AuNPs-CaCO3), hybrid material was encapsulated by silica sol on a glassy carbon electrode (GCE). The fabricated modified electrode was used as a novel voltammetric sensor for electrochemical sensing of anti-HIV replication drug i.e. deferiprone. The surface morphology of the modified electrode was characterized by scanning electron microscopy (SEM). Results obtained from the voltammetric measurements show that HRP-AuNPs-CaCO3 modified GCE offers a selective and sensitive electrochemical sensor for the determination of deferiprone. Under experimental conditions, the proposed voltammetric sensor has a linear response range from 0.01 to 10,000 µM with a detection limit of 0.01 µM. Furthermore, the fabricated sensor was successfully applied to determine deferiprone level in spiked urine and serum samples.


Assuntos
Técnicas Biossensoriais , Carbonato de Cálcio/química , Monitoramento de Medicamentos/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanocompostos/química , Fármacos Anti-HIV/análise , Fármacos Anti-HIV/sangue , Fármacos Anti-HIV/urina , Deferiprona , Técnicas Eletroquímicas , Eletrodos , Grafite/química , Peroxidase do Rábano Silvestre/química , Humanos , Limite de Detecção , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanotecnologia , Transição de Fase , Piridonas/análise , Piridonas/sangue , Piridonas/urina , Dióxido de Silício/química , Temperatura
13.
Indian J Med Res ; 139(4): 603-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24927348

RESUMO

BACKGROUND & OBJECTIVES: Reusable biostrip consisting enzymes immobilized onto alkylamine glass beads affixed on plasticized PVC strip for determination of triglyceride (TG) suffers from high cost of beads and their detachments during washings for reuse, leading to loss of activity. The purpose of this study was to develop a cheaper and stable biostrip for investigation of TG levels in serum. METHODS: A reusable enzyme-strip was prepared for TG determination by co-immobilizing lipase, glycerol kinase (GK), glycerol-3-phosphate oxidase (GPO) and peroxidase (HRP) directly onto plasticized polyvinyl chloride (PVC) strip through glutaraldehyde coupling. The method was evaluated by studying its recovery, precision and reusability. RESULTS: The enzyme-strip showed optimum activity at pH 7.0, 35 o C and a linear relationship between its activity and triolein concentration in the range 0.1 to 15 mM. The strip was used for determination of serum TG. The detection limit of the method was 0.1 mM. Analytical recovery of added triolein was 96 per cent. Within and between batch coefficients of variation (CV) were 2.2 and 3.7 per cent, respectively. A good correlation (r=0.99) was found between TG values by standard enzymic colrimetric method employing free enzymes and the present method. The strip lost 50 per cent of its initial activity after its 200 uses during the span of 100 days, when stored at 4 o C. INTERPRETATION & CONCLUSIONS: The nitrating acidic treatment of plasticized PVC strip led to glutaraldehyde coupling of four enzymes used for enzymic colourimetric determination of serum TG. The strip provided 200 reuses of enzymes with only 50 per cent loss of its initial activity. The method could be used for preparation of other enzyme strips also.


Assuntos
Análise Química do Sangue/instrumentação , Enzimas Imobilizadas/metabolismo , Cloreto de Polivinila/metabolismo , Fitas Reagentes/metabolismo , Triglicerídeos/sangue , Glicerol Quinase/metabolismo , Glicerolfosfato Desidrogenase/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Lipase/metabolismo , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
14.
ACS Appl Bio Mater ; 7(4): 2299-2308, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38476032

RESUMO

Smartphones' widespread availability and worldwide connection are advancing the idea of mobile-based healthcare and promise to transform the business of biosensors. Biosensors based on smartphones have been investigated in several ways, including employing a smartphone in place of a detector or as an instrumental interface. The current work demonstrates the first successful detection of dengue virus using a smartphone-based pocket sensor combined with a wireless potentiostat. The platform developed comprises a smartphone, a wireless portable potentiostat, an Android app, and a three-electrode setup. The combination of portable diagnostic with electronic application is referred to as "Portronicx", and this is the first time that the term "Portronicx" has been used in a dengue sensor, so the current study has the potential to be commercialized in the market with the tag line "Portronicx-commercialization" in the future. Miniaturization improves alternative setup options in terms of instrument size, affordability, mobility, touch-mobile display, and design versatility. The current work proved the excellent combination of a wireless potentiostat with an aptasensor to detect dengue antigen within 20 s with good LOD (0.1 µg/mL) and easy to carry in their pockets. The created platform also performed effectively in human serum. This study replaced all of the instruments with a lightweight touch smartphone, paving the way for the production of fifth-generation electrochemical aptasensors, with potential implications for healthcare applications on the verge of commercialization.


Assuntos
Técnicas Biossensoriais , Dengue , Humanos , Smartphone , Eletrodos , Dengue/diagnóstico
15.
Biosensors (Basel) ; 14(7)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39056620

RESUMO

Medical devices have progressed from their initial bulky forms to smart devices. However, their rigidity hampers their seamless integration into everyday life. The fields of stretchable, textile, and flexible electronics are emerging research areas with the potential to drive significant technological progress. This research presents a laboratory-based technique to produce highly sensitive and flexible biosensors for detecting the chikungunya virus. These biosensors are based on 0D nanomaterials and demonstrate significant advancements in voltammetry. The electrochemical platform was created utilizing the stencil printing (StPE) technique. Adapting the biosensor setup involved the selection of aptamer as the biorecognition element bound with silver nanoparticles (AgNPs). This biosensor was employed in the voltammetric identification of the Chikungunya virus antigen (CHIKV-Ag) within a solution containing 0.5 mM potassium ferro/ferri cyanide, a redox pair. The biosensor was employed to evaluate CHIKV-Ag within a human serum sample. It demonstrated a linear detection span ranging from 0.1 ng/mL to 1 µg/mL, with a detection limit of 0.1 ng/mL for CHIKV-Ag. The proposed approach, due to its flexibility in production and the electrocatalytic attributes displayed by the zero-dimensional nanostructure, presents innovative opportunities for cost-effective and tailored aptamer-based bioelectronics, thereby broadening the scope of this domain.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Carbono , Vírus Chikungunya , Técnicas Eletroquímicas , Eletrodos , Nanopartículas Metálicas , Prata , Prata/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Humanos , Carbono/química , Tinta , Limite de Detecção
16.
Micromachines (Basel) ; 15(3)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38542559

RESUMO

Ketamine is one of the most commonly abused drugs globally, posing a severe risk to social stability and human health, not only it is being used for recreational purposes, but this tasteless, odourless, and colourless drug also facilitates sexual assaults when it is mixed with drinks. Ketamine abuse is a threat for safety, and this misuse is one of the main uses of the drug. The crucial role of ketamine detection is evident in its contributions to forensic investigations, law enforcement, drug control, workplace integrity, and public health. Electrochemical sensors have gained considerable interest among researchers due to their various advantages, such as low cost and specificity, and particularly screen-printed paper-based electrode (SPBE) biosensors have gained attention. Here, we reported an ePAD (electrochemical paper-based analytical device) for detecting the recreational drug ketamine. The advantages of using a paper-based electrode are that it reduces the electrode's production costs and is disposable and environmentally friendly. At the same time, nanographite sheets (NGSs) assisted in amplifying the signals generated in the cyclic voltammetry system when ketamine was present. This ePAD was developed by immobilizing a ketamine aptamer on NGS electrodes. The characterization of proper synthesized NGSs was performed by Scanning Electron Microscopy (SEM), XRD (X-ray Diffraction), Fourier-transform infrared spectroscopy (FTIR), and UV-Vis spectroscopy. Electrochemical techniques, including cyclic voltammetry (CV) and linear sweep voltammetry (LSV), were employed to validate the results and confirm each attachment. Furthermore, the versatility of the proposed sensor was explored in both alcoholic and non-alcoholic beverages. The developed sensor showed a low LOD of about 0.01 µg/mL, and the linear range was between 0.01 and 5 µg/mL. This approach offers a valid diagnostic technique for onsite service with minimal resources. This cost effective and portable platform offers desirable characteristics like sensitivity and selectivity and can also be used for POC (point of care) testing to help in the quick identification of suspicious samples and for testing at trafficking sites, amusement parks, and by the side of the road.

17.
Biosens Bioelectron ; 263: 116561, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39033654

RESUMO

The current work shows the advancement of an additive manufactured multiplex immunosensor for the detection of dengue serotypes 1&2 in dengue patients on a single device with the LOD of 12.5 ng/ml. In this work, we created a QR-Code enabled additive manufactured case comprised of a paper-based electrode coated with ZnO NPs, which helps to enhance the detection signal and make it more selective, both serotype antibodies (DENV1-Ab & DENV2-Ab) were employed against DENV serotypes (DENV1-Ag & DENV2-Ag. QR-code technology was also integrated with the established platform to deliver sensor supporting information so that anybody may quickly obtain supporting sensing result details by scanning with a smartphone. The proposed highly advanced platform successfully detected DENV serotypes in dengue patients and showing a wide range of detection from 12.5 to 200 ng/ml with a LOD of 12.5 ng/ml.The results were also validated with conventional testing, i.e., Indirect Fluorescence Antibody Test (IFAT), so the developed multiplex-sensor became more applicable for the detection of DENV serotypes on a single tool having high sensitivity and selectivity, with a potential of commercialization.


Assuntos
Anticorpos Antivirais , Técnicas Biossensoriais , Vírus da Dengue , Dengue , Sorogrupo , Humanos , Dengue/diagnóstico , Dengue/imunologia , Dengue/virologia , Dengue/sangue , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Vírus da Dengue/isolamento & purificação , Vírus da Dengue/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Imunoensaio/métodos , Imunoensaio/instrumentação , Limite de Detecção
18.
Bioprocess Biosyst Eng ; 36(11): 1545-54, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23411873

RESUMO

A method is described for the construction of a highly sensitive amperometric sensor for the detection of tyrosine, employing a magnetic nanoparticles-zinc oxide/zinc hexacyanoferrate (Fe3O4NP-ZnO/ZnHCF) hybrid film electrodeposited on the surface of a Pt electrode as working electrode. The sensor is based on electrocatalytic mechanism initiated by electrochemical oxidation of the reduced form of the hybrid film at +0.2 V vs. Ag/AgCl followed by completion of chemical oxidation of tyrosine. The sensor showed optimum response within 2 s at pH 2. The working/linear range of the sensor was 0.02-2.76 mM with a detection limit of 4 µM. The sensor measured tyrosine level in serum, a potential biomarker of phenylketonuria. The working electrode lost only 5 % of its initial activity, when stored at 4 °C, after its regular use over a period of 100 days.


Assuntos
Técnicas Eletroquímicas/métodos , Ferrocianetos/química , Magnetismo , Nanopartículas , Tirosina/análise , Óxido de Zinco/química , Catálise , Limite de Detecção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução , Reprodutibilidade dos Testes , Difração de Raios X
19.
Bioprocess Biosyst Eng ; 36(4): 425-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22903594

RESUMO

A method is described for construction of an amperometric triglyceride (TG) biosensor based on covalent co-immobilization of lipase, glycerol kinase and glycerol-3-phosphate oxidase onto gold polypyrrole nanocomposite decorated poly indole-5-carboxylic acid electrodeposited on the surface of a gold electrode. The enzyme electrode was characterized by transmission electron microscopy, scanning electron microscopy, electrochemical impedance studies, Fourier transform infrared spectroscopy and cyclic voltammetry. Biosensor showed optimum response within 4 s at pH 6.5 and 35 °C, when polarized at +0.1 V against Ag/AgCl. There was a linear relationship between sensor response and triolein concentration in the range 50-700 mg/dl. Biosensor was employed for determination of TG in serum. Detection limit of the biosensor was 20 mg/dl. Biosensor was evaluated with 91-95 % recovery of added triolein in sera and 4.14 and 5.85 % within and between batch coefficients of variation, respectively. There was a good correlation (r = 0.99) between sera TG values by standard method (Enzymic colorimetric) and the present method. The biosensor was unaffected by a number of serum substances at their physiological concentration. Biosensor lost 50 % of its initial activity after its 100 uses over 7 months, when stored at 4 °C.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanopartículas Metálicas , Nanocompostos , Triglicerídeos/sangue , Adulto , Técnicas Biossensoriais/métodos , Análise Química do Sangue/instrumentação , Análise Química do Sangue/métodos , Espectroscopia Dielétrica , Enzimas Imobilizadas , Glicerol Quinase , Glicerolfosfato Desidrogenase , Ouro , Humanos , Indóis , Lipase , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica , Nanocompostos/química , Nanocompostos/ultraestrutura , Polímeros , Pirróis , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Biosensors (Basel) ; 13(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887127

RESUMO

Illicit drug misuse has become a widespread issue that requires continuous drug monitoring and diagnosis. Wearable electrochemical drug detection devices possess the potential to function as potent screening instruments in the possession of law enforcement personnel, aiding in the fight against drug trafficking and facilitating forensic investigations conducted on site. These wearable sensors are promising alternatives to traditional detection methods. In this study, we present a novel wearable electrochemical glove-based analytical device (eGAD) designed especially for detecting the club drug, methamphetamine. To develop this sensor, we immobilized meth aptamer onto silver nanoparticle (AgNPs)-modified electrodes that were printed onto latex gloves. The characteristics of AgNPs, including their shape, size and purity were analysed using FTIR, SEM and UV vis spectrometry, confirming the successful synthesis. The developed sensor shows a 0.1 µg/mL limit of detection and 0.3 µg/mL limit of quantification with a linear concentration range of about 0.01-5 µg/mL and recovery percentages of approximately 102 and 103%, respectively. To demonstrate its applicability, we tested the developed wearable sensor by spiking various alcoholic and non-alcoholic drink samples. We found that the sensor remains effective for 60 days, making it a practical option with a reasonable shelf-life. The developed sensor offers several advantages, including its affordability, ease of handling and high sensitivity and selectivity. Its portable nature makes it an ideal tool for rapid detection of METH in beverages too.


Assuntos
Nanopartículas Metálicas , Metanfetamina , Dispositivos Eletrônicos Vestíveis , Nanopartículas Metálicas/química , Prata/química , Eletrodos , Técnicas Eletroquímicas/métodos
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