A multipurpose biochip for food pathogen detection

2016 ◽  
Vol 8 (15) ◽  
pp. 3055-3060 ◽  
Author(s):  
Elisabetta Primiceri ◽  
Maria Serena Chiriacò ◽  
Francesco de Feo ◽  
Elisa Santovito ◽  
Vincenzina Fusco ◽  
...  
Keyword(s):  
Pathogen Detection ◽  
Low Cost ◽  
High Sensitivity ◽  
Label Free ◽  
Food Pathogen

We realized an innovative biosensing platform with high sensitivity, low-cost and label-free features forS. aureusandL. monocytogenesdetection from meat.

scholarly journals Integrating high-performing electrochemical transducers in lateral flow assay

2021 ◽  
Author(s):  
Antonia Perju ◽  
Nongnoot Wongkaew
Keyword(s):  
High Performance ◽  
Point Of Care ◽  
Low Cost ◽  
High Sensitivity ◽  
Lateral Flow ◽  
Analytical Performance ◽  
Label Free ◽  
High Performing ◽  
Lateral Flow Assays ◽  
Electrochemical Transducers

AbstractLateral flow assays (LFAs) are the best-performing and best-known point-of-care tests worldwide. Over the last decade, they have experienced an increasing interest by researchers towards improving their analytical performance while maintaining their robust assay platform. Commercially, visual and optical detection strategies dominate, but it is especially the research on integrating electrochemical (EC) approaches that may have a chance to significantly improve an LFA’s performance that is needed in order to detect analytes reliably at lower concentrations than currently possible. In fact, EC-LFAs offer advantages in terms of quantitative determination, low-cost, high sensitivity, and even simple, label-free strategies. Here, the various configurations of EC-LFAs published are summarized and critically evaluated. In short, most of them rely on applying conventional transducers, e.g., screen-printed electrode, to ensure reliability of the assay, and additional advances are afforded by the beneficial features of nanomaterials. It is predicted that these will be further implemented in EC-LFAs as high-performance transducers. Considering the low cost of point-of-care devices, it becomes even more important to also identify strategies that efficiently integrate nanomaterials into EC-LFAs in a high-throughput manner while maintaining their favorable analytical performance.

scholarly journals Colorimetric Sensing with Gold Nanoparticles on Electrowetting-Based Digital Microfluidics

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1423
Author(s):  
Zhen Gu ◽  
Jing-Jing Luo ◽  
Le-Wei Ding ◽  
Bing-Yong Yan ◽  
Jia-Le Zhou ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Low Cost ◽  
Digital Microfluidics ◽  
High Sensitivity ◽  
Bulk Solution ◽  
Label Free ◽  
Colorimetric Sensing ◽  
Wide Range ◽  
The Stability ◽  
Digital Microfluidic

Digital microfluidic (DMF) has been a unique tool for manipulating micro-droplets with high flexibility and accuracy. To extend the application of DMF for automatic and in-site detection, it is promising to introduce colorimetric sensing based on gold nanoparticles (AuNPs), which have advantages including high sensitivity, label-free, biocompatibility, and easy surface modification. However, there is still a lack of studies for investigating the movement and stability of AuNPs for in-site detection on the electrowetting-based digital microfluidics. Herein, to demonstrate the ability of DMF for colorimetric sensing with AuNPs, we investigated the electrowetting property of the AuNPs droplets on the hydrophobic interface of the DMF chip and examined the stability of the AuNPs on DMF as well as the influence of evaporation to the colorimetric sensing. As a result, we found that the electrowetting of AuNPs fits to a modified Young–Lippmann equation, which suggests that a higher voltage is required to actuate AuNPs droplets compared with actuating water droplets. Moreover, the stability of AuNPs was maintained during the processing of electrowetting. We also proved that the evaporation of droplets has a limited influence on the detections that last several minutes. Finally, a model experiment for the detection of Hg2+ was carried out with similar results to the detections in bulk solution. The proposed method can be further extended to a wide range of AuNPs-based detection for label-free, automatic, and low-cost detection of small molecules, biomarkers, and metal ions.

Cocaine detection using aptamer and molybdenum disulfide-gold nanoparticle-based sensors

Nanomedicine ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. 325-335
Author(s):  
Li Gao ◽  
Wenwen Xiang ◽  
Zebin Deng ◽  
Keqing Shi ◽  
Huixing Wang ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Detection Limit ◽  
Molybdenum Disulfide ◽  
Low Cost ◽  
High Sensitivity ◽  
Label Free ◽  
Sensing System ◽  
Plasmon Resonance Band ◽  
Resonance Band ◽  
Cocaine Detection

Aim: The current work highlighted a novel colorimetric sensor based on aptamer and molybdenum disulfide (MoS2)-gold nanoparticles (AuNPs) that was developed for cocaine detection with high sensitivity. Materials & methods: Due to the presence of the plasmon resonance band on the surface of AuNPs, AuNPs aggregated and the color was changed from red to blue after adding a certain concentration of NaCl. We used MoS2 to optimize the sensing system of AuNPs. The folded conformation of the aptamer in combination with cocaine enhanced the salt tolerance of the MoS2-AuNPs, effectively preventing their aggregation. Results & conclusion: The detection limit of cocaine was 7.49 nM with good selectivity. The method based on MoS2-AuNPs colorimetry sensor is simple, quick, label-free and low cost.

scholarly journals Portable tumor biosensing of serum by plasmonic biochips in combination with nanoimprint and microfluidics

Nanophotonics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 307-316 ◽  
Author(s):  
Jianyang Zhou ◽  
Feng Tao ◽  
Jinfeng Zhu ◽  
Shaowei Lin ◽  
Zhengying Wang ◽  
...  
Keyword(s):  
Nanoimprint Lithography ◽  
Clinical Medicine ◽  
Point Of Care ◽  
Low Cost ◽  
Human Tumor ◽  
High Sensitivity ◽  
Visible Range ◽  
Label Free ◽  
Portable Detection ◽  
Clinical Experiments

AbstractPlasmonic sensing has a great potential in the portable detection of human tumor markers, among which the carcinoembryonic antigen (CEA) is one of the most widely used in clinical medicine. Traditional plasmonic and non-plasmonic methods for CEA biosensing are still not suitable for the fast developing era of Internet of things. In this study, we build up a cost-effective plasmonic immunochip platform for rapid portable detection of CEA by combining soft nanoimprint lithography, microfluidics, antibody functionalization, and mobile fiber spectrometry. The plasmonic gold nanocave array enables stable surface functionality, high sensitivity, and simple reflective measuring configuration in the visible range. The rapid quantitative CEA sensing is implemented by a label-free scheme, and the detection capability for the concentration of less than 5 ng/ml is achieved in clinical experiments, which is much lower than the CEA cancer diagnosis threshold of 20 ng/ml and absolutely sufficient for medical applications. Clinical tests of the chip on detecting human serums demonstrate good agreement with conventional medical examinations and great advantages on simultaneous multichannel detections for high-throughput and multi-marker biosensing. Our platform provides promising opportunities on low-cost and compact medical devices and systems with rapid and sensitive tumor detection for point-of-care diagnosis and mobile healthcare.

scholarly journals Fast infectious diseases diagnostics based on microfluidic biochip system

2017 ◽  
Vol 10 (02) ◽  
pp. 1650044 ◽  
Author(s):  
Qin Huang ◽  
Shanqiao Han ◽  
Yan Zhang ◽  
Yue Kou ◽  
Xiaohang Zhao ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Molecular Diagnostics ◽  
Microfluidic Chip ◽  
Pathogen Detection ◽  
Low Cost ◽  
High Sensitivity ◽  
Optical Diffraction ◽  
Fluorescence Detector ◽  
Total Analysis System ◽  
Amplification Method

Molecular diagnostics is one of the most important tools currently in use for clinical pathogen detection due to its high sensitivity, specificity, and low consume of sample and reagent is keyword to low cost molecular diagnostics. In this paper, a sensitive DNA isothermal amplification method for fast clinical infectious diseases diagnostics at aM concentrations of DNA was developed using a polycarbonate (PC) microfluidic chip. A portable confocal optical fluorescence detector was specifically developed for the microfluidic chip that was capable of highly sensitive real-time detection of amplified products for sequence-specific molecular identification near the optical diffraction limit with low background. The molecular diagnostics of Listeria monocytogenes with nucleic acid extracted from stool samples was performed at a minimum DNA template concentration of 3.65[Formula: see text]aM, and a detection limit of less than five copies of genomic DNA. Contrast to the general polymerase chain reaction (PCR) at eppendorf (EP) tube, the detection time in our developed method was reduced from 1.5[Formula: see text]h to 45[Formula: see text]min for multi-target parallel detection, the consume of sample and reagent was dropped from 25[Formula: see text][Formula: see text]L to 1.45[Formula: see text][Formula: see text]L. This novel microfluidic chip system and method can be used to develop a micro total analysis system as a clinically relevant pathogen molecular diagnostics method via the amplification of targets, with potential applications in biotechnology, medicine, and clinical molecular diagnostics.

Optimization of MEMS Design for a Synchronous Magnetic Sensor

2007 ◽  
Author(s):  
S. Chandrasekaran ◽  
E. Berkcan
Keyword(s):  
Thin Film ◽  
Pathogen Detection ◽  
Microelectromechanical Systems ◽  
Gas Sensing ◽  
Low Cost ◽  
High Sensitivity ◽  
Vibration Monitoring ◽  
Flow Sensing ◽  
Biological Warfare Agents ◽  
Warfare Agents

Microelectromechanical systems offer variety of advantages such as small size, higher sensitivity, low cost because of mass fabrication capabilities and ease of implementation. Thin film cantilever based devices have been successfully used for variety of applications not limited to chemical vapors for chemical agents, biological warfare agents, contaminants in water, explosives, acoustics, vibration monitoring, flow sensing, viscosity and density measurements, antibody, pathogen detection, acceleration, shock sensing and magnetic field sensing. Thin film cantilevers can easily realized on silicon and other surfaces. Microcantilevers supported on one edge of the substrate can be designed to demonstrate very high sensitivity to very less force of the order of piconewtons. These structures could be extended for application in gas sensing if chemically sensitive layer is added on to the cantilever. The dimensions of the cantilever determine the sensitivity. Cantilevers as thin as few tenths of nanometer in thickness has been successfully demonstrated. Challenge associated with these devices when used as a sensor is their response to shock and acceleration.

Identification of Fluids by the Color of Surface Plasmon Polaritons

2014 ◽  
Vol 625 ◽  
pp. 316-321
Author(s):  
Miyu Ozaki ◽  
Tomohisa Sakai ◽  
Hiromichi Murata ◽  
Ryoshu Furutani
Keyword(s):  
Refractive Index ◽  
Surface Plasmon ◽  
Surface Plasmon Polaritons ◽  
White Light ◽  
Low Cost ◽  
High Sensitivity ◽  
Light Illumination ◽  
Label Free ◽  
Free Electrons ◽  
Plasmon Polaritons

When optical waves make the free electrons on a metal surface resonate, optical energy propagates along the surface as density waves of the free electrons. The longitudinal waves and electrical fields of the electrons are called surface plasmon polaritons (SPPs), which are widely applied in high sensitivity sensors because the excitation of SPPs sensitively depends on the refractive index of the surrounding dielectric sample. Here, we report the identification of fluids by using the color dispersion of SPPs. Silver film on a prism surface is illuminated with white light to excite SPPs. A color component in the white light is thereby selectively coupled with SPPs due to the color dispersion that depends on the refractive index of the fluid on the film. Thus, theoretically, when the refractive index is changed, the color of SPPs changes as well. Our application uses a medium consisting of fluid samples to be identified. The proposed identification method can be applied to fluid analysis for label-free visualization of or as a simple analysis method, since the refractive indices or concentrations of the sample fluids directly affect the color of the SPPs, and this color can be visually identified. We theoretically confirmed that the color of SPPs excited with white light illumination can help to differentiate between water and ethanol. Experimentally, SPPs belonging to the frequency region of the color green were detected when the sample was water, and the color changed to red when ethanol was used instead. In the future, we plan to develop simple, small, sensitive, and low-cost sensors that can determine the concentration and refractive index of fluids on the basis of the color of the SPPs.

scholarly journals Fundamentals and applications of SERS-based bioanalytical sensing

Nanophotonics ◽  
2017 ◽  
Vol 6 (5) ◽  
pp. 831-852 ◽  
Author(s):  
Mehmet Kahraman ◽  
Emma R. Mullen ◽  
Aysun Korkmaz ◽  
Sebastian Wachsmann-Hogiu
Keyword(s):  
Point Of Care ◽  
Low Cost ◽  
High Sensitivity ◽  
Chemical Information ◽  
Label Free ◽  
Analytical Technique ◽  
Sers Substrates ◽  
Interface Surface ◽  
Bioanalytical Applications ◽  
Care Technology

AbstractPlasmonics is an emerging field that examines the interaction between light and metallic nanostructures at the metal-dielectric interface. Surface-enhanced Raman scattering (SERS) is a powerful analytical technique that uses plasmonics to obtain detailed chemical information of molecules or molecular assemblies adsorbed or attached to nanostructured metallic surfaces. For bioanalytical applications, these surfaces are engineered to optimize for high enhancement factors and molecular specificity. In this review we focus on the fabrication of SERS substrates and their use for bioanalytical applications. We review the fundamental mechanisms of SERS and parameters governing SERS enhancement. We also discuss developments in the field of novel SERS substrates. This includes the use of different materials, sizes, shapes, and architectures to achieve high sensitivity and specificity as well as tunability or flexibility. Different fundamental approaches are discussed, such as label-free and functional assays. In addition, we highlight recent relevant advances for bioanalytical SERS applied to small molecules, proteins, DNA, and biologically relevant nanoparticles. Subsequently, we discuss the importance of data analysis and signal detection schemes to achieve smaller instruments with low cost for SERS-based point-of-care technology developments. Finally, we review the main advantages and challenges of SERS-based biosensing and provide a brief outlook.

scholarly journals Highly Sensitive Electrochemical Aptasensor for Detecting the VEGF165 Tumor Marker with PANI/CNT Nanocomposites

Biosensors ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 114
Author(s):  
Yunjeong Park ◽  
Min-Sung Hong ◽  
Woo-Hyuk Lee ◽  
Jung-Gu Kim ◽  
Kyunghoon Kim
Keyword(s):  
Tumor Marker ◽  
Limit Of Detection ◽  
Biological Fluid ◽  
Low Cost ◽  
High Sensitivity ◽  
Label Free ◽  
Electrochemical Aptasensor ◽  
Promising Tool ◽  
Highly Sensitive ◽  
Endothelial Growth Factor

Sensing targeted tumor markers with high sensitivity provides vital information for the fast diagnosis and treatment of cancer patients. A vascular endothelial growth factor (VEGF165) have recently emerged as a promising biomarker of tumor cells. The electrochemical aptasensor is a promising tool for detecting VEGF165 because of its advantages such as a low cost and quantitative analysis. To produce a sensitive and stable sensor electrode, nanocomposites based on polyaniline (PANI) and carbon nanotube (CNT) have potential, as they provide for easy fabrication, simple synthesis, have a large surface area, and are suitable in biological environments. Here, a label-free electrochemical aptasensor based on nanocomposites of CNT and PANI was prepared for detecting VEGF165 as a tumor marker. The nanocomposite was assembled with immobilized VEGF165 aptamer as a highly sensitive VEGF165 sensor. It exhibited stable and wide linear detection ranges from 0.5 pg/mL to 1 μg/mL, with a limit of detection of 0.4 pg/mL because of the complementary effect of PANI/CNT. The fabricated aptasensor also exhibited good stability in biological conditions, selectivity, and reproducibility after several measurement times after the dissociation process. Thus, it could be applied for the non-invasive determination of VEGF, in biological fluid diagnosis kits, or in an aptamer-based biosensor platform in the near future.

Sign in / Sign up

Export Citation Format

Share Document