scholarly journals Monoclonal Antibodies Application in Lateral Flow Immunochromatographic Assays for Drugs of Abuse Detection

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1058
Author(s):  
Zidane Qriouet ◽  
Yahia Cherrah ◽  
Hassan Sefrioui ◽  
Zineb Qmichou
Keyword(s):  
High Performance ◽  
Drugs Of Abuse ◽  
Limit Of Detection ◽  
Lateral Flow ◽  
Detection Sensitivity ◽  
Gas Chromatography Mass Spectrometry ◽  
Resource Limited ◽  
Short Period ◽  
Reaction Gas Chromatography ◽  
Lateral Flow Assays

Lateral flow assays (lateral flow immunoassays and nucleic acid lateral flow assays) have experienced a great boom in a wide variety of early diagnostic and screening applications. As opposed to conventional examinations (High Performance Liquid Chromatography, Polymerase Chain Reaction, Gas chromatography-Mass Spectrometry, etc.), they obtain the results of a sample’s analysis within a short period. In resource-limited areas, these tests must be simple, reliable, and inexpensive. In this review, we outline the production process of antibodies against drugs of abuse (such as heroin, amphetamine, benzodiazepines, cannabis, etc.), used in lateral flow immunoassays as revelation or detection molecules, with a focus on the components, the principles, the formats, and the mechanisms of reaction of these assays. Further, we report the monoclonal antibody advantages over the polyclonal ones used against drugs of abuse. The perspective on aptamer use for lateral flow assay development was also discussed as a possible alternative to antibodies in view of improving the limit of detection, sensitivity, and specificity of lateral flow assays.

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.

Development of a Smartphone Based Reader for the Quantitative Analysis of Lateral Flow Assays

2018 ◽  
Vol 941 ◽  
pp. 2522-2527
Author(s):  
Sylvio Schneider ◽  
Martina Selig ◽  
Verena Keil ◽  
Matthias Lehmann ◽  
Andreas H. Foitzik ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Medical Devices ◽  
Limit Of Detection ◽  
Point Of Care ◽  
Thrombotic Event ◽  
Lateral Flow ◽  
Proof Of Concept ◽  
Lateral Flow Assays ◽  
Further Development ◽  
D Dimer

Smartphones are developing into all-purposes devices. In the present work, the employment/application of smartphones as medical devices in home care and point-of-care (POC) diagnostics are investigated in the analysis of Lateral Flow Assays (LFA). A smartphone-based LFA reader was developed for the quantitative analysis of D-Dimer – a biomarker indicating e.g. thrombotic event or danger of embolism.The proof-of-concept has been shown with multiple smartphones in establishing: (I) Optimal dimensions of the LFA cell of 72.11mm distance of smartphone to D-Dimer test leading to a coefficients of variances (CV) between 0.8% and 4.2%. (II) Inter-device investigations: CVs around 13.5%; a limit of detection (LOD) of 100ng/ml (DDU) D-Dimer. (III) Inter-smartphone investigations: CV about 16%, a limit of detection (LOD) at 66.4ng/ml (DDU). (IV) Calibrations: CV and LOD of three smartphones are comparable to the commercial available LFA reader. Further development to put the multiple smartphone-based LFA reader on the market.

scholarly journals Diagnosis of Histoplasmosis Using the MVista Histoplasma Galactomannan Antigen Qualitative Lateral Flow–Based Immunoassay: A Multicenter Study

2021 ◽  
Vol 8 (9) ◽  
Author(s):  
Wassim Abdallah ◽  
Thein Myint ◽  
Richard LaRue ◽  
Melissa Minderman ◽  
Suphansa Gunn ◽  
...  
Keyword(s):  
Severe Disease ◽  
The United States ◽  
Cross Reactivity ◽  
Lateral Flow ◽  
Medical Centers ◽  
Resource Limited ◽  
Pulmonary Histoplasmosis ◽  
Lateral Flow Assays ◽  
Poor Outcomes ◽  
Endemic Mycoses

Abstract Background Accurate and timely methods for the diagnosis of histoplasmosis in resource-limited countries are lacking. Histoplasma antigen detection by enzyme immunoassay (EIA) is widely used in the United States (US) but not in resource-limited countries, leading to missed or delayed diagnoses and poor outcomes. Lateral flow assays (LFAs) can be used in this setting. Methods Frozen urine specimens were submitted to MiraVista diagnostics for antigen testing from 3 medical centers in endemic areas of the US. They were blinded and tested for the MVista Histoplasma LFA. Patients were classified as controls or cases of histoplasmosis. Cases were divided into proven or probable; pulmonary or disseminated; immunocompetent or immunosuppressed; and mild, moderate, or severe. Results Three hundred fifty-two subjects were enrolled, including 66 cases (44 proven, 22 probable) and 286 controls. Most of the cases were immunocompromised (71%), and 46 had disseminated and 20 had pulmonary histoplasmosis. Four cases were mild, 42 moderate, and 20 severe. LFA and EIA were highly concordant (κ = 0.84). Sensitivity and specificity of the LFA were 78.8% and 99.3%, respectively. LFA sensitivity was higher in proven cases (93.2%), patients with disseminated (91.3%), moderate (78.6%), and severe disease (80%), and those with galactomannan levels >1.8 ng/mL (97.8%). Specificity was 99.3% in proven cases, 99.3% in patients with moderate or severe disease, and 96.8% in those with galactomannan levels >1.8 ng/mL. Cross-reactivity was noted with other endemic mycoses. Conclusions The MVista Histoplasma LFA meets the need for accurate rapid diagnosis of histoplasmosis in resource-limited countries, especially in patients with high disease burden, potentially reducing morbidity and mortality.

scholarly journals Instrumentation-Free Semiquantitative Immunoanalysis Using a Specially Patterned Lateral Flow Assay Device

Biosensors ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 87
Author(s):  
Kyung Won Lee ◽  
Ye Chan Yu ◽  
Hyeong Jin Chun ◽  
Yo Han Jang ◽  
Yong Duk Han ◽  
...  
Keyword(s):  
Limit Of Detection ◽  
Optical Probe ◽  
Lateral Flow ◽  
Analyte Concentration ◽  
Detection Range ◽  
Optical Instruments ◽  
Naked Eye ◽  
Resource Limited ◽  
Test Zone ◽  
Artificial Urine

In traditional colorimetric lateral flow immunoassay (LFI) using gold nanoparticles (AuNPs) as a probe, additional optical transducers are required to quantify the signal intensity of the test line because it presents as a single red-colored line. In order to eliminate external equipment, the LFI signal should be quantifiable by the naked eye without the involvement of optical instruments. Given this objective, the single line test zone of conventional LFI was converted to several spots that formed herringbone patterns. When the sandwich immunoassay was performed on a newly developed semi-quantitative (SQ)-LFI system using AuNPs as an optical probe, the spots were colorized and the number of colored spots increased proportionally with the analyte concentration. By counting the number of colored spots, the analyte concentration can be easily estimated with the naked eye. To demonstrate the applicability of the SQ-LFI system in practical immunoanalysis, microalbumin, which is a diagnostic marker for renal failure, was analyzed using microalbumin-spiked artificial urine samples. Using the SQ-LFI system, the calibration results for artificial urine-based microalbumin were studied, ranging from 0 to 500 μg/mL, covering the required clinical detection range, and the limit of detection (LOD) value was calculated to be 15.5 μg/mL. Thus, the SQ-LFI system provides an avenue for the realization of an efficient quantification diagnostic device in resource-limited conditions.

Excellence in Laboratory Practice with the Validation of Opiate Confirmation using Liquid Chromatography/Mass Spectrometry

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S34-S34
Author(s):  
S Dalal ◽  
D Jhala
Keyword(s):  
Mass Spectrometry ◽  
Liquid Chromatography ◽  
Sample Preparation ◽  
Drugs Of Abuse ◽  
Limit Of Detection ◽  
Gas Chromatography Mass Spectrometry ◽  
Liquid Chromatography Mass Spectrometry ◽  
Laboratory Practice ◽  
Ion Suppression ◽  
Chromatography Mass Spectrometry

Abstract Introduction/Objective Veterans are more susceptible to opioid addiction as they are more likely to suffer from chronic pain which leads to increased need of confirmed identification of opiates in toxicology laboratories. Gas chromatography-mass spectrometry (GC-MS) had been a long-accepted method for the quantitative analysis of opiates in urine, but requires tedious, time-consuming, and complex sample preparation steps. On the other hand, liquid chromatography-mass spectrometry (LC/MS) has comparatively simpler sample preparation steps, can handle three times the number of specimens, much faster turnaround times and produces equally valid results. However, the validation experience of this simpler detection method has not been well published, particularly in a Veterans Healthcare Clinical Laboratory setting. Methods/Case Report The quality assurance goal of the validation is to demonstrate that the Agilent 6410 Triple Quadrupole LC/MS (Wilmington DE) is able to identify the same opiate drug analytes performed by the GC-MS. Method to method correlation, within run precision, day to day precision, carryover study, matrix (ion) suppression study, and a limit of detection study were performed as part of this validation. Results (if a Case Study enter NA) For the total of 156 specimens run for the method comparison, there was 94.9% agreement, or 148/156 samples were concordant. The 8 discrepancies had drugs that were present below the cutoff limit of the LC/MS. Within run precision with 20 replicates of negative, positive, and at the cutoff were run with all results as expected. The day to day precision of a positive and negative sample run over 10 days also yielded results as expected. The carryover study demonstrated minimal carryover. The matrix (ion) suppression study showed ion suppression at 16.8%, which is below the amount needed to affect analyte concentrations. The LC/MS was highly sensitive with a limit of detection of >97% at 25 ng/mL. Thus, the result of comparison showed good concordance. Conclusion LC/MS is a simpler, more efficient method of opiate testing that is comparable to GC-MS for the detection of opiate drugs of abuse in urine. This is an example of excellence in laboratory practice by extending the best quality laboratory care with proper validation of instrument methods conducive to laboratory workflow.

scholarly journals Electrospun Polycaprolactone Nanofibers as a Reaction Membrane for Lateral Flow Assay

Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1387 ◽  
Author(s):  
Chee Yew ◽  
Pedram Azari ◽  
Jane Choi ◽  
Farina Muhamad ◽  
Belinda Pingguan-Murphy
Keyword(s):  
Flow Rate ◽  
Point Of Care ◽  
Low Cost ◽  
Average Pore Size ◽  
Lateral Flow ◽  
Detection Sensitivity ◽  
Average Pore ◽  
Water Contact ◽  
Naoh Solution ◽  
Lateral Flow Assays

Electrospun polycaprolactone (PCL) nanofibers have emerged as a promising material in diverse biomedical applications due to their various favorable features. However, their application in the field of biosensors such as point-of-care lateral flow assays (LFA) has not been investigated. The present study demonstrates the use of electrospun PCL nanofibers as a reaction membrane for LFA. Electrospun PCL nanofibers were treated with NaOH solution for different concentrations and durations to achieve a desirable flow rate and optimum detection sensitivity in nucleic acid-based LFA. It was observed that the concentration of NaOH does not affect the physical properties of nanofibers, including average fiber diameter, average pore size and porosity. However, interestingly, a significant reduction of the water contact angle was observed due to the generation of hydroxyl and carboxyl groups on the nanofibers, which increased their hydrophilicity. The optimally treated nanofibers were able to detect synthetic Zika viral DNA (as a model analyte) sensitively with a detection limit of 0.5 nM. Collectively, the benefits such as low-cost of fabrication, ease of modification, porous nanofibrous structures and tunability of flow rate make PCL nanofibers a versatile alternative to nitrocellulose membrane in LFA applications. This material offers tremendous potential for a broad range of point-of-care applications.

scholarly journals Comparison of ELISAs for Opiates, Methamphetamine, Cocaine Metabolite, Benzodiazepines, Phencyclidine, and Cannabinoids in Whole Blood and Urine

2001 ◽  
Vol 47 (3) ◽  
pp. 540-547 ◽  
Author(s):  
Sarah Kerrigan ◽  
William H Phillips Jr
Keyword(s):  
Whole Blood ◽  
Drugs Of Abuse ◽  
Detection Limits ◽  
Comparative Assessment ◽  
Analytical Performance ◽  
Detection Sensitivity ◽  
Mass Spectrometry Analysis ◽  
Gas Chromatography Mass Spectrometry ◽  
Response Curves ◽  
Binding Characteristics

Abstract Background: ELISAs are widely utilized in forensic drug analysis. A comparative assessment of microtiter plate assays for the detection of six common classes of drug in blood and urine is described. Methods: ELISAs for opiates, methamphetamine, benzodiazepines, cocaine metabolite, phencyclidine (PCP), and tetrahydrocannabinol (THC) metabolite were evaluated in a side-by-side study. The analytical performance of 12 commercially available ELISAs was determined in terms of binding characteristics, dose–response curves, limits of detection, sensitivity, intra- and interassay imprecision, and lot-to-lot reproducibility. Assay performance was also compared using 855 forensic casework samples. Results: Detection limits in whole blood for morphine, d-methamphetamine, nordiazepam, benzoylecgonine, nordiazepam, PCP, and l-11-nor-9-carboxy-Δ9-THC were 3, 2, <4, 5, 25, and 3 μg/L, respectively, for the STC ELISAs. Corresponding detection limits for Immunalysis ELISAs were <1, <2, <4, 5, <1, and 1 μg/L, respectively. Intraassay CVs (n = 8) at the immunoassay cutoff concentrations were 4.1–5.6% and 3.5–11% for STC and Immunalysis ELISAs, respectively. Corresponding interassay CVs were 3.1–10% and 6.5–20%. Of the 855 casework samples, there were a total of 92 discordant results (44 cannabinoid, 15 opiate, 15 methamphetamine, 11 benzodiazepine, and 7 cocaine metabolite). Gas chromatography–mass spectrometry analysis indicated a total of three unconfirmed positive results for Immunalysis assays and one unconfirmed positive for STC assays. Conclusions: A comparative assessment of drugs-of-abuse assays from two manufacturers indicated some key differences in analytical performance. Overall, Immunalysis assays offered superior binding characteristics and detection limits, whereas STC assays offered improved overall precision and lot-to-lot reproducibility.

scholarly journals A Rapid and Sensitive Fluorescent Microsphere-Based Lateral Flow Immunoassay for Determination of Aflatoxin B1 in Distillers’ Grains

Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2109
Author(s):  
Zifei Wang ◽  
Pengjie Luo ◽  
Baodong Zheng
Keyword(s):  
Aflatoxin B1 ◽  
High Performance ◽  
Animal Feed ◽  
Limit Of Detection ◽  
Lateral Flow ◽  
Distillers Grains ◽  
Detection Methods ◽  
Lateral Flow Immunoassay ◽  
Quantitative Detection ◽  
Fluorescent Microsphere

Aflatoxin B1 (AFB1) is a toxic compound naturally produced by the genera Aspergillus. Distillers’ grains can be used as animal feed since they have high content of crude protein and other nutrients. However, they are easily contaminated by mycotoxins, and currently there are no rapid detection methods for AFB1 in distillers’ grains. In this study, a lateral flow immunoassay (LFIA) based on red fluorescent microsphere (FM), is developed for quantitative detection of AFB1 in distillers’ grains. The whole test can be completed within 15 min, with the cut-off value being 25.0 μg/kg, and the quantitative limit of detection (qLOD) being 3.4 μg/kg. This method represents satisfactory recoveries of 95.2–113.0%, and the coefficients of variation (CVs) are less than 7.0%. Furthermore, this technique is successfully used to analyze AFB1 in real samples, and the results indicates good consistency with that of high-performance liquid chromatography (HPLC). The correlation coefficient is found to be greater than 0.99. The proposed test strip facilitates on-site, cost-effective, and sensitive monitoring of AFB1 in distillers’ grains.

scholarly journals Identification of the Source of Reagent Variability in the Xanthydrol/Urea Method

1998 ◽  
Vol 81 (6) ◽  
pp. 1155-1161 ◽  
Author(s):  
Patricia Valdes Biles ◽  
George C Ziobro
Keyword(s):  
Food Packaging ◽  
Limit Of Detection ◽  
Packaging Material ◽  
Detection Sensitivity ◽  
Gas Chromatography Mass Spectrometry ◽  
Liquid Chromatographic Method ◽  
Aoac Method ◽  
Liquid Chromatographic ◽  
Chemical Indicator ◽  
Urea Method

Abstract Contamination of food and food packaging material by rodent urine is evidence of insanitary conditions. Urea from rodent urine is used as a chemical indicator of contamination. The limit of detection of the xanthydrol/urea AOAC Method 959.14 by formation of dixanthylurea crystals is 4 μg urea isolated from urine on packaging material. Six different lots of xanthydrol from 5 different manufacturers were compared. Differences in urea detection sensitivity of the xanthydrol of up to 1000-fold were observed. Melting points showed further evidence of variability and impurities in xanthydrol lots. A liquid chromatographic method was developed to separate and identify the impurities. Confirmation of analytes was performed by gas chromatography/mass spectrometry.

Sign in / Sign up

Export Citation Format

Share Document