A low-cost smart system for electrophoresis-based nucleic acids detection at the visible spectrum

ABSTRACTNucleic acid detection by electrophoresis is still a quick and accessible technique for many diagnosis methods, primarily at research laboratories or at the point of care units. Standard protocols detect DNA/RNA molecules through specific bound chemical dyes using a UV-transilluminator or UV-photo documentation system. However, the acquisition costs and availability of these devices, mainly the ones with photography and internet connection capabilities, can be prohibitive, especially in developing countries public health units. Also, ultraviolet radiation is a common additional risk factor to professionals that use electrophoresis-based nucleic acid detection. With that in mind, this work describes the development of a low-cost DNA/RNA detection smart system capable of obtaining qualitative and semi-quantitative data from gel analysis. The proposed device explores the visible light absorption range of commonly used DNA/RNA dyes using readily available parts, and simple manufacturing processes, such as light-emitting diodes (LEDs) and 3D impression. By applying IoT techniques, our system covers a wide range of color spectrum in order to detect bands from various commercially used dyes, using Bluetooth communication and a smartphone for hardware control, image capturing, and sharing. The project also enables process scalability and has low manufacturing and maintenance costs. The use of LEDs at the visible spectrum can achieve very reproducible images, providing a high potential for rapid and point-of-care diagnostics as well as applications in several fields such as healthcare, agriculture, and aquaculture.

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Shallow Water Bathymetry Inversion Using Hybrid Multi-band Composites Resulted from Integration of Drone-based RGB and Multispectral Imagery

10.20944/preprints202112.0414.v2 ◽

2022 ◽

Author(s):

Evangelos Alevizos ◽

Athanasios V Argyriou ◽

Dimitris Oikonomou ◽

Dimitrios D Alexakis

Keyword(s):

Low Cost ◽

Visible Spectrum ◽

Small Scale ◽

Multispectral Imagery ◽

Depth Data ◽

Recent Developments ◽

Model Tuning ◽

Inversion Techniques ◽

Camera Sensors ◽

Current Inversion

Shallow bathymetry inversion algorithms have long been applied in various types of remote sensing imagery with relative success. However, this approach requires that imagery with increased radiometric resolution in the visible spectrum is available. The recent developments in drones and camera sensors allow for testing current inversion techniques on new types of datasets. This study explores the bathymetric mapping capabilities of fused RGB and multispectral imagery, as an alternative to costly hyperspectral sensors. Combining drone-based RGB and multispectral imagery into a single cube dataset, provides the necessary radiometric detail for shallow bathymetry inversion applications. This technique is based on commercial and open-source software and does not require input of reference depth measurements in contrast to other approaches. The robustness of this method was tested on three different coastal sites with contrasting seafloor types. The use of suitable end-member spectra which are representative of the seafloor types of the study area and the sun zenith angle are important parameters in model tuning. The results of this study show good correlation (R2>0.7) and less than half a meter error when they are compared with sonar depth data. Consequently, integration of various drone-based imagery may be applied for producing centimetre resolution bathymetry maps at low cost for small-scale shallow areas.

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Nucleic acid-based biosensors: analytical devices for prevention, diagnosis and treatment of diseases

Revista Vitae ◽

10.17533/udea.vitae.v28n3a347259 ◽

2021 ◽

Vol 28 (3) ◽

Author(s):

Laura Carvajal Barbosa ◽

Diego Insuasty Cepeda ◽

Andrés Felipe León Torres ◽

Maria Mercedes Arias Cortes ◽

Zuly Jenny Rivera Monroy ◽

...

Keyword(s):

Food Safety ◽

Nucleic Acid ◽

Nucleic Acids ◽

Pathogenic Bacteria ◽

High Selectivity ◽

Low Cost ◽

Analytical Techniques ◽

High Sensitivity ◽

Disease Status ◽

Public Health Issue

BACKGROUND : Biosensing techniques have been the subject of exponentially increasing interest due to their performance advantages such as high selectivity and sensitivity, easy operation, low cost, short analysis time, simple sample preparation, and real-time detection. Biosensors have been developed by integrating the unique specificity of biological reactions and the high sensitivity of physical sensors. Therefore, there has been a broad scope of applications for biosensing techniques, and nowadays, they are ubiquitous in different areas of environmental, healthcare, and food safety. Biosensors have been used for environmental studies, detecting and quantifying pollutants in water, air, and soil. Biosensors also showed great potential for developing analytical tools with countless applications in diagnosing, preventing, and treating diseases, mainly by detecting biomarkers. Biosensors as a medical device can identify nucleic acids, proteins, peptides, metabolites, etc.; these analytes may be biomarkers associated with the disease status. Bacterial food contamination is considered a worldwide public health issue; biosensor-based analytical techniques can identify the presence or absence of pathogenic agents in food. OBJECTIVES: The present review aims to establish state-of-the-art, comprising the recent advances in the use of nucleic acid-based biosensors and their novel application for the detection of nucleic acids. Emphasis will be given to the performance characteristics, advantages, and challenges. Additionally, food safety applications of nucleic acid-based biosensors will be discussed. METHODS: Recent research articles related to nucleic acid-based biosensors, biosensors for detecting nucleic acids, biosensors and food safety, and biosensors in environmental monitoring were reviewed. Also, biosensing platforms associated with the clinical diagnosis and food industry were included. RESULTS: It is possible to appreciate that multiple applications of nucleic acid-based biosensors have been reported in the diagnosis, prevention, and treatment of diseases, as well as to identify foodborne pathogenic bacteria. The use of PNA and aptamers opens the possibility of developing new biometric tools with better analytical properties. CONCLUSIONS: Biosensors could be considered the most important tool for preventing, treating, and monitoring diseases that significantly impact human health. The aptamers have advantages as biorecognition elements due to the structural conformation, hybridization capacity, robustness, stability, and lower costs. It is necessary to implement biosensors in situ to identify analytes with high selectivity and lower detection limits.

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Interaction of cyanine dyes with nucleic acids. 8. Investigation of cyanine dyes as fluorescent probes for the nucleic acids detection

Biopolymers and Cell ◽

10.7124/bc.00052f ◽

1999 ◽

Vol 15 (4) ◽

pp. 328-336 ◽

Cited By ~ 1

Author(s):

S. M. Yarmoluk

Keyword(s):

Nucleic Acids ◽

Fluorescent Probes ◽

Cyanine Dyes ◽

Nucleic Acids Detection

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Isolation of Nucleic Acids Using Fly Ash as a Low-Cost Adsorbent

Analytical Letters ◽

10.1080/00032719.2020.1835938 ◽

2020 ◽

pp. 1-14

Author(s):

Pongsakorn Thawornpan ◽

Supinya Thanapongpichat ◽

Aung Win Tun ◽

Watthanachai Jumpathong ◽

Luitzen de Jong ◽

...

Keyword(s):

Fly Ash ◽

Nucleic Acids ◽

Low Cost

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Compressive Sensing Based Three-Dimensional Imaging Method with Electro-Optic Modulation for Nonscanning Laser Radar

Symmetry ◽

10.3390/sym12050748 ◽

2020 ◽

Vol 12 (5) ◽

pp. 748

Author(s):

Yulong An ◽

Yanmei Zhang ◽

Haichao Guo ◽

Jing Wang

Keyword(s):

Compressive Sensing ◽

3D Imaging ◽

Low Cost ◽

Functional Model ◽

Three Dimensional ◽

Visible Spectrum ◽

Depth Map ◽

Imaging Method ◽

Practical Applications ◽

Electro Optic

Low-cost Laser Detection and Ranging (LiDAR) is crucial to three-dimensional (3D) imaging in applications such as remote sensing, target detection, and machine vision. In conventional nonscanning time-of-flight (TOF) LiDAR, the intensity map is obtained by a detector array and the depth map is measured in the time domain which requires costly sensors and short laser pulses. To overcome such limitations, this paper presents a nonscanning 3D laser imaging method that combines compressive sensing (CS) techniques and electro-optic modulation. In this novel scheme, electro-optic modulation is applied to map the range information into the intensity of echo pulses symmetrically and the measurements of pattern projection with symmetrical structure are received by the low bandwidth detector. The 3D imaging can be extracted from two gain modulated images that are recovered by solving underdetermined inverse problems. An integrated regularization model is proposed for the recovery problems and the minimization functional model is solved by a proposed algorithm applying the alternating direction method of multiplier (ADMM) technique. The simulation results on various subrates for 3D imaging indicate that our proposed method is feasible and achieves performance improvement over conventional methods in systems with hardware limitations. This novel method will be highly valuable for practical applications with advantages of low cost and flexible structure at wavelengths beyond visible spectrum.

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