scholarly journals A GPCR-based yeast biosensor for biomedical, biotechnological, and point-of-use cannabinoid determination

2022 ◽  
Author(s):  
Karel Miettinen ◽  
Nattawat Leelahakorn ◽  
Aldo Almeida ◽  
Yong Zhao ◽  
Lukas Hansen ◽  
...  
Keyword(s):  
Dynamic Range ◽  
Low Cost ◽  
Real Life ◽  
High Sensitivity ◽  
Structural Diversity ◽  
High Throughput Analysis ◽  
Synthetic Drugs ◽  
Point Of Use ◽  
Whole Cell Biosensor ◽  
G Protein Coupled

Abstract The decriminalization of cannabis and the growing interest in cannabinoids as therapeutics require efficient methods to discover novel compounds and monitor cannabinoid levels in human samples and products. However, current methods are limited by the structural diversity of the active compounds. Here, we construct a G-protein coupled receptor-based yeast whole-cell biosensor, optimize it to achieve high sensitivity and dynamic range, and prove its effectiveness in three real-life applications. First, we screen a library of compounds to discover two novel agonists and four antagonists and demonstrate that our biosensor can democratize GPCR drug discovery by enabling low-cost high-throughput analysis using open-source automation. Subsequently, we bioprospect 54 plants to discover a novel phytocannabinoid, dugesialactone. Finally, we develop a robust portable device, analyze body-fluid samples, and confidently detect illicit synthetic drugs like “Spice”/“K2”. Taking advantage of the extensive sensing repertoire of GPCRs, this technology can be extended to detect numerous other compounds.

scholarly journals Conformational pathway provides unique sensitivity to a synaptic mGluR

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Chris H. Habrian ◽  
Joshua Levitz ◽  
Vojtech Vyklicky ◽  
Zhu Fu ◽  
Adam Hoagland ◽  
...  
Keyword(s):  
Single Molecule ◽  
Metabotropic Glutamate Receptors ◽  
Dynamic Range ◽  
High Sensitivity ◽  
G Protein Coupled Receptors ◽  
Metabotropic Glutamate ◽  
Single Molecule Fret ◽  
Broad Dynamic Range ◽  
Maximal Activation ◽  
G Protein Coupled

AbstractMetabotropic glutamate receptors (mGluRs) are dimeric G-protein–coupled receptors that operate at synapses. Macroscopic and single molecule FRET to monitor structural rearrangements in the ligand binding domain (LBD) of the mGluR7/7 homodimer revealed it to have an apparent affinity ~4000-fold lower than other mGluRs and a maximal activation of only ~10%, seemingly too low for activation at synapses. However, mGluR7 heterodimerizes, and we find it to associate with mGluR2 in the hippocampus. Strikingly, the mGluR2/7 heterodimer has high affinity and efficacy. mGluR2/7 shows cooperativity in which an unliganded subunit greatly enhances activation by agonist bound to its heteromeric partner, and a unique conformational pathway to activation, in which mGluR2/7 partially activates in the Apo state, even when its LBDs are held open by antagonist. High sensitivity and an unusually broad dynamic range should enable mGluR2/7 to respond to both glutamate transients from nearby release and spillover from distant synapses.

scholarly journals Nanotechnology in emerging liquid biopsy applications

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Despina P. Kalogianni
Keyword(s):  
Liquid Biopsy ◽  
Dynamic Range ◽  
Low Cost ◽  
Invasive Procedure ◽  
High Sensitivity ◽  
Attractive Alternative ◽  
Sample Collection ◽  
Comprehensive Overview ◽  
Early Cancer Diagnosis ◽  
Wide Range

AbstractLiquid biopsy is considered as the most attractive alternative to traditional tissue biopsies. The major advantages of this approach lie in the non-invasive procedure, the rapidness of sample collection and the potential for early cancer diagnosis and real-time monitoring of the disease and the treatment response. Nanotechnology has dynamically emerged in a wide range of applications in the field of liquid biopsy. The benefits of using nanomaterials for biosensing include high sensitivity and detectability, simplicity in many cases, rapid analysis, the low cost of the analysis and the potential for portability and personalized medicine. The present paper reports on the nanomaterial-based methods and biosensors that have been developed for liquid biopsy applications. Most of the nanomaterials used exhibit great analytical performance; moreover, extremely low limits of detection have been achieved for all studied targets. This review will provide scientists with a comprehensive overview of all the nanomaterials and techniques that have been developed for liquid biopsy applications. A comparison of the developed methods in terms of detectability, dynamic range, time-length of the analysis and multiplicity, is also provided.

scholarly journals Silicon Photomultipliers as a Low-Cost Fluorescence Detector for Capillary Electrophoresis

2020 ◽  
Author(s):  
Brae Petersen ◽  
Luke Gallion ◽  
Nancy Allbritton
Keyword(s):  
Capillary Electrophoresis ◽  
Open Source ◽  
Dynamic Range ◽  
Low Cost ◽  
Single Cells ◽  
Detection Limits ◽  
High Sensitivity ◽  
Small Sample ◽  
Fluorescence Detector ◽  
Silicon Photomultipliers

Capillary electrophoresis (CE) is a highly efficient separation method capable of handling small sample volumes (~pL) and low (~yoctomole) detection limits, and as such is ideal for applications that require high sensitivity such as single-cell analysis. Low-cost CE instrumentation is quickly expanding but low-cost, open-source fluorescence detectors with ultra-sensitive detection limits are lacking. Silicon photomultipliers (SiPM) are inexpensive, low-footprint detectors with the potential to fill the role as a detector when cost, size, and customization are important. In this work we demonstrate the use of a SiPM in CE with zeptomolar detection limits and a dynamic range spanning five orders of magnitude, comparable to photomultiplier detectors. We characterize the performance of the SiPM as a highly sensitive detector by measuring enzyme activity in single cells. This simple, small footprint, and low-cost (<$130) light detection circuit will be beneficial for open-source, portable, and budget friendly instrumentation requiring high sensitivity.<br>

scholarly journals A SARS-CoV-2 aptasensor based on electrochemical impedance spectroscopy and low-cost gold electrode substrates.

2021 ◽  
Author(s):  
Perrine Lasserre ◽  
Banushan Balansethupathy ◽  
Vincent J. Vezza ◽  
Adrian Butterworth ◽  
Alexander MacDonald ◽  
...  
Keyword(s):  
Electrochemical Impedance ◽  
Low Cost ◽  
Glucose Monitoring ◽  
High Sensitivity ◽  
Blood Glucose Monitoring ◽  
Label Free ◽  
Rna Sequences ◽  
Point Of Use ◽  
Lateral Flow Assays ◽  
Impedimetric Biosensor

SARS-CoV-2 diagnostic practices broadly involve either qPCR based nucleic amplification or lateral flow assays (LFAs). qPCR based techniques suffer from the disadvantage of requiring thermal cycling (difficult to implement for low-cost field use) leading to limitation on sample to answer time, the potential to amplify viral RNA sequences after a person is no longer infectious and being reagent intense. LFA performance is restricted by qualitative or semi-quantitative readouts, limits on sensitivity and poor reproducibility. Electrochemical biosensors, and particularly glucose test strips, present an appealing platform for development of biosensing solutions for SARS-CoV-2 as they can be multiplexed and implemented at very low cost at point of use with high sensitivity and quantitative digital readout. This work reports the successful raising of an Opti-mer sequence for the spike protein of SARS-CoV-2 and then development of an impedimetric biosensor which utilises thin film gold sensors on low-cost laminate substrates from home blood glucose monitoring. Clinically relevant detection levels for SARS-CoV-2 are achieved in a simple, label-free measurement format using sample incubation times of 15 minutes. The biosensor developed here is compatible with mass manufacture, is sensitive and low-cost CE marked readout instruments already exist. These findings pave the way to a low cost and mass manufacturable test with the potential to overcome the limitations associated with current technologies.

scholarly journals Label-Free Assays on the BIND System

2004 ◽  
Vol 9 (6) ◽  
pp. 481-490 ◽  
Author(s):  
Brian T. Cunningham ◽  
Peter Li ◽  
Stephen Schulz ◽  
Bo Lin ◽  
Cheryl Baird ◽  
...  
Keyword(s):  
Fluorescent Dyes ◽  
Dynamic Range ◽  
Low Cost ◽  
High Sensitivity ◽  
Receptor Expression ◽  
Label Free ◽  
Protein Protein Interaction ◽  
Small Molecule Screening ◽  
Guided Mode ◽  
Wide Range

Screening of biochemical interactions becomes simpler, less expensive, and more accurate when labels, such as fluorescent dyes, radioactive markers, and colorimetric reactions, are not required to quantify detected material. SRU Biosystems has developed a biosensor technology that is manufactured on continuous sheets of plastic film and incorporated into standard microplates and microarray slides to enable label-free assays to be performed with high throughput, high sensitivity, and low cost per assay. The biosensor incorporates a narrow band guided-mode resonance reflectance filter, in which the reflected color is modulated by the attachment/detachment of biochemical material to the surface. The technology offers 4 orders of linear dynamic range and uniformity within a plate, with a coefficient of variation of 2.5%. Using conventional biochemical immobilization surface chemistries, a wide range of assay applications are enabled. Small molecule screening, cell proliferation/cytotoxicity, enzyme activity screening, protein-protein interaction, and cell membrane receptor expression are among the applications demonstrated.

scholarly journals Label-Free Fluorescent Aptasensor for Small Targets via Displacement of Groove Bound Curcumin Molecules

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4181 ◽  
Author(s):  
Baraa J. Alyamani ◽  
Omar A. Alsager ◽  
Mohammed Zourob
Keyword(s):  
Small Molecules ◽  
Dynamic Range ◽  
Fluorescent Sensor ◽  
Low Cost ◽  
High Sensitivity ◽  
Synthetic Dyes ◽  
Label Free ◽  
Target Molecule ◽  
Small Targets ◽  
Aptamer Sequence

Signal transduction based on fluorescence is one of the most common optical aptasensors for small molecules. Sensors with a number of unique features including high sensitivity, low cost, and simple operation can be constructed easily. However, the label-free fluorescent approach is limited to synthetic dyes that bind strongly to the aptamer sequence and result in a diminished sensor operation with high detection limits. In this study, we report the use of curcumin as a fluorescent probe to signal aptamer/small target binding events. A substantial enhancement in curcumin’s fluorescent emission was observed when bound into the grooves of vitamin D3 (VTD3) binding aptamer, as an example. However, the introduction of the target molecule causes the aptamer to undergo a conformational change that favors complexing the target molecule over binding the curcumin dye. The sensor was able to detect VTD3 down to 1 fM concentration in buffer solutions and extracted blood samples, operate at a wide dynamic range, and discriminate against potential biological interfering molecules including VTD2. The operation of the curcumin based fluorescent sensor is at least six orders of magnitude more sensitive than a VTD3 sensor constructed with the synthetic dye SYBR Green I. The generality of the reported label-free approach was applied with a previously isolated 75-mer bisphenol-A (BPA) aptamer, confirming that the reported sensing strategy is not confined on a particular aptamer sequence. Our work not only reports a novel sensor format for the detection of small molecules, but also serves fluorescent sensor’s most pressing need being novel fluorophores for multiplex targets detection.

scholarly journals Review of Recent Advances in QEPAS-Based Trace Gas Sensing

2018 ◽  
Vol 8 (10) ◽  
pp. 1822 ◽  
Author(s):  
Yufei Ma
Keyword(s):  
Photoacoustic Spectroscopy ◽  
Dynamic Range ◽  
Gas Sensing ◽  
Low Cost ◽  
Piezoelectric Element ◽  
High Sensitivity ◽  
Quartz Tuning Fork ◽  
Trace Gas ◽  
Sensitivity And Selectivity ◽  
Trace Gas Sensing

Quartz-enhanced photoacoustic spectroscopy (QEPAS) is an improvement of the conventional microphone-based photoacoustic spectroscopy. In the QEPAS technique, a commercially available millimeter-sized piezoelectric element quartz tuning fork (QTF) is used as an acoustic wave transducer. With the merits of high sensitivity and selectivity, low cost, compactness, and a large dynamic range, QEPAS sensors have been applied widely in gas detection. In this review, recent developments in state-of-the-art QEPAS-based trace gas sensing technique over the past five years are summarized and discussed. The prospect of QEPAS-based gas sensing is also presented.

Silicon Photomultipliers as a Low-Cost Fluorescence Detector for Capillary Electrophoresis

2020 ◽  
Author(s):  
Brae Petersen ◽  
Luke Gallion ◽  
Nancy Allbritton
Keyword(s):  
Capillary Electrophoresis ◽  
Open Source ◽  
Dynamic Range ◽  
Low Cost ◽  
Single Cells ◽  
Detection Limits ◽  
High Sensitivity ◽  
Small Sample ◽  
Fluorescence Detector ◽  
Silicon Photomultipliers

Capillary electrophoresis (CE) is a highly efficient separation method capable of handling small sample volumes (~pL) and low (~yoctomole) detection limits, and as such is ideal for applications that require high sensitivity such as single-cell analysis. Low-cost CE instrumentation is quickly expanding but low-cost, open-source fluorescence detectors with ultra-sensitive detection limits are lacking. Silicon photomultipliers (SiPM) are inexpensive, low-footprint detectors with the potential to fill the role as a detector when cost, size, and customization are important. In this work we demonstrate the use of a SiPM in CE with zeptomolar detection limits and a dynamic range spanning five orders of magnitude, comparable to photomultiplier detectors. We characterize the performance of the SiPM as a highly sensitive detector by measuring enzyme activity in single cells. This simple, small footprint, and low-cost (<$130) light detection circuit will be beneficial for open-source, portable, and budget friendly instrumentation requiring high sensitivity.<br>

scholarly journals LAMP-Coupled CRISPR–Cas12a Module for Rapid and Sensitive Detection of Plant DNA Viruses

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 466
Author(s):  
Ahmed Mahas ◽  
Norhan Hassan ◽  
Rashid Aman ◽  
Tin Marsic ◽  
Qiaochu Wang ◽  
...  
Keyword(s):  
Low Cost ◽  
Virus Detection ◽  
High Sensitivity ◽  
Plant Viruses ◽  
Economic Losses ◽  
New Delhi ◽  
Dna Viruses ◽  
Point Of Use ◽  
Tomato Leaf Curl ◽  
Leaf Curl

One important factor for successful disease management is the ability to rapidly and accurately identify the causal agent. Plant viruses cause severe economic losses and pose a serious threat to sustainable agriculture. Therefore, optimization of the speed, sensitivity, feasibility, portability, and accuracy of virus detection is urgently needed. Here, we developed a clustered regularly interspaced short palindromic repeats (CRISPR)-based nucleic acid diagnostic method utilizing the CRISPR–Cas12a system for detecting two geminiviruses, tomato yellow leaf curl virus (TYLCV) and tomato leaf curl New Delhi virus (ToLCNDV), which have single-stranded DNA genomes. Our assay detected TYLCV and ToLCNDV in infected plants with high sensitivity and specificity. Our newly developed assay can be performed in ~1 h and provides easy-to-interpret visual readouts using a simple, low-cost fluorescence visualizer, making it suitable for point-of-use applications.

scholarly journals Molecular genetic methods in biomedical research. Part III: human gene diagnostics in clinical practice

2021 ◽  
Vol 6 (3) ◽  
pp. 100-109
Author(s):  
A. N. Volkov ◽  
L. V. Nacheva
Keyword(s):  
Low Cost ◽  
Molecular Genetic ◽  
Real Life ◽  
High Sensitivity ◽  
Response To Treatment ◽  
Individual Response ◽  
Technical Simplicity ◽  
The Individual ◽  
Gene Diagnostics ◽  
Pcr Diagnostics

Application of molecular genetic methods in the diagnosis and treatment of human diseases is extremely wide due to a huge amount of hereditary information contained in the human genome. Gene diagnostics allows establishing predisposition to diseases, identification of genetic abnormalities and prediction of pathological outcomes. In addition, gene diagnostics also enables prediction of the individual response to treatment in order to achieve the maximum therapeutic effect. Among all molecular genetic methods, polymerase chain reaction (PCR) diagnostics is a leading approach. Technical simplicity, low cost, high sensitivity and reliability of the method have made PCR diagnostics a routine modality for the risk assessment, diagnostics, and monitoring of the treatment efficiency. Here, we consider the application of PCR diagnostics for the abovementioned tasks and talk about the real-life examples of detecting mutations and chromosomal aberrations which may cause a disease. Further, we discuss the prospects of using a semi-quantitative PCR in medical practice and focus on pharmacogenetics as a key component of a personalised therapy. The lecture is aimed primarily at biomedical students and physicians and represents a continuation of the previous lectures published in Fundamental and Clinical Medicin.

Sign in / Sign up

Export Citation Format

Share Document