Performance of a FRET-Based Point-of-Care Immunoassay for the Quantitation of Fecal Calprotectin

A fast (~5 min), time-resolved fluorescence resonance energy transfer based immunoassay (Procise FCP<a>™</a>) was developed for the point-of-care quantitative detection of fecal calprotectin (FCP) using 15 mg of fecal specimen eluted in collection fluid from the Procise Stool Collection Device™. Studies were performed to characterize analytical performance of the Procise FCP assay on the ProciseDx™ analyzer. The Procise FCP assay showed good analytical performance with respect to sensitivity, specificity, linearity, and precision suitable for routine clinical use in a point-of-care setting as well as excellent analytical agreement with a current commercial FCP measurement method. Results indicate that the Procise FCP assay is sensitive, specific, and precise yielding results in less than 5 minutes. This indicates the Procise FCP assay is useful for obtaining fast and accurate FCP quantitation, thus avoiding delays inherent to current methods and enabling immediate clinical assessment to be made during a single patient visit.

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Therapeutic Drug Monitoring: Performance of a FRET-Based Point-Of-Care Immunoassay for the Quantitation of Infliximab and Adalimumab in Blood

10.26434/chemrxiv.13277321.v1 ◽

2020 ◽

Author(s):

Edgar Ong ◽

Ruo Huang ◽

Richard Kirkland ◽

Stefan Westin ◽

Jared Salbato ◽

...

Keyword(s):

Therapeutic Drug Monitoring ◽

Drug Monitoring ◽

Whole Blood ◽

Point Of Care ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Drug Level ◽

Analytical Performance ◽

Quantitative Detection ◽

Therapeutic Drug

Two fast (<5 min), time-resolved fluorescence resonance energy transfer (FRET)-based immunoassays (Procise IFX™ and Procise ADL™) were developed for the quantitative detection of infliximab (IFX), adalimumab (ADL), and their respective biosimilars for use in therapeutic drug monitoring (TDM) using 20 µL of finger prick whole blood at the point-of-care or whole blood/serum in a central lab. Studies were performed to characterize analytical performance of the Procise IFX and the Procise ADL assays on the ProciseDx™ analyzer. The Procise IFX and Procise ADL assays both showed good analytical performance with respect to sensitivity, specificity, linearity, and precision suitable for routine clinical use as well as excellent correlation to current commercial ELISA IFX and ADL measurement methods. Results indicated that the Procise IFX and Procise ADL assays are sensitive, specific, and precise yielding results in less than 5 minutes from either whole blood or serum. This indicates the Procise IFX and Procise ADL assays are useful for obtaining fast and accurate IFX or ADL quantitation, thus avoiding delays inherent to current methods and enabling immediate drug level dosing decisions to be made during a single patient visit.

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Therapeutic Drug Monitoring: Performance of a FRET-Based Point-Of-Care Immunoassay for the Quantitation of Infliximab and Adalimumab in Blood

10.26434/chemrxiv.13277321 ◽

2020 ◽

Author(s):

Edgar Ong ◽

Ruo Huang ◽

Richard Kirkland ◽

Stefan Westin ◽

Jared Salbato ◽

...

Keyword(s):

Therapeutic Drug Monitoring ◽

Drug Monitoring ◽

Whole Blood ◽

Point Of Care ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Drug Level ◽

Analytical Performance ◽

Quantitative Detection ◽

Therapeutic Drug

Two fast (<5 min), time-resolved fluorescence resonance energy transfer (FRET)-based immunoassays (Procise IFX™ and Procise ADL™) were developed for the quantitative detection of infliximab (IFX), adalimumab (ADL), and their respective biosimilars for use in therapeutic drug monitoring (TDM) using 20 µL of finger prick whole blood at the point-of-care or whole blood/serum in a central lab. Studies were performed to characterize analytical performance of the Procise IFX and the Procise ADL assays on the ProciseDx™ analyzer. The Procise IFX and Procise ADL assays both showed good analytical performance with respect to sensitivity, specificity, linearity, and precision suitable for routine clinical use as well as excellent correlation to current commercial ELISA IFX and ADL measurement methods. Results indicated that the Procise IFX and Procise ADL assays are sensitive, specific, and precise yielding results in less than 5 minutes from either whole blood or serum. This indicates the Procise IFX and Procise ADL assays are useful for obtaining fast and accurate IFX or ADL quantitation, thus avoiding delays inherent to current methods and enabling immediate drug level dosing decisions to be made during a single patient visit.

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Therapeutic Drug Monitoring: Performance of a FRET-Based Point-Of-Care Immunoassay for the Quantitation of Infliximab and Adalimumab in Blood

10.26434/chemrxiv.13277321.v2 ◽

2020 ◽

Author(s):

Edgar Ong ◽

Ruo Huang ◽

Richard Kirkland ◽

Stefan Westin ◽

Jared Salbato ◽

...

Keyword(s):

Therapeutic Drug Monitoring ◽

Drug Monitoring ◽

Whole Blood ◽

Point Of Care ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Drug Level ◽

Analytical Performance ◽

Quantitative Detection ◽

Therapeutic Drug

Two fast (<5 min), time-resolved fluorescence resonance energy transfer (FRET)-based immunoassays (Procise IFX™ and Procise ADL™) were developed for the quantitative detection of infliximab (IFX), adalimumab (ADL), and their respective biosimilars for use in therapeutic drug monitoring (TDM) using 20 µL of finger prick whole blood at the point-of-care or whole blood/serum in a central lab. Studies were performed to characterize analytical performance of the Procise IFX and the Procise ADL assays on the ProciseDx™ analyzer. The Procise IFX and Procise ADL assays both showed good analytical performance with respect to sensitivity, specificity, linearity, and precision suitable for routine clinical use as well as excellent correlation to current commercial ELISA IFX and ADL measurement methods. Results indicated that the Procise IFX and Procise ADL assays are sensitive, specific, and precise yielding results in less than 5 minutes from either whole blood or serum. This indicates the Procise IFX and Procise ADL assays are useful for obtaining fast and accurate IFX or ADL quantitation, thus avoiding delays inherent to current methods and enabling immediate drug level dosing decisions to be made during a single patient visit.

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Time-resolved Fluorescence Resonance Energy Transfer Assay for Point-of-Care Testing of Urinary Albumin

Clinical Chemistry ◽

10.1373/49.7.1105 ◽

2003 ◽

Vol 49 (7) ◽

pp. 1105-1113 ◽

Cited By ~ 41

Author(s):

Qiu-Ping Qin ◽

Olli Peltola ◽

Kim Pettersson

Keyword(s):

Energy Transfer ◽

Fluorescence Resonance Energy Transfer ◽

Limit Of Detection ◽

Point Of Care ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Time Resolved ◽

Urine Albumin ◽

Europium Chelate ◽

Fluorescence Resonance

Abstract Background: Microalbuminuria is an established early marker of diabetic nephropathy and an important cardiovascular risk factor in diabetes and hypertension. We aimed to develop a rapid point-of-care assay for the measurement of urine albumin. Methods: The competitive homogeneous assay used an albumin-specific monoclonal antibody labeled with a stable fluorescent europium chelate as donor and an albumin labeled with cyanine 5 (Cy5) as acceptor. The assay was performed at room temperature in single microtitration wells that contained all the required dry-form reagents. The close proximity between the two labels in the immune complex allowed fluorescence resonance energy to be transferred from the pulse-excited europium chelate to the acceptor Cy5. The emission of long-lived energy transfer signal from the sensitized Cy5 was measured at 665 nm with time-resolved fluorometry that eliminated short-lived background. Results: The assay procedure required 12 min for a 10-μL urine sample. The working range was from 10 to ∼320 mg/L, and the lower limit of detection was 5.5 mg/L. The within- and between-run CVs were 6.9–10% and 7.5–13%, respectively. Recovery was 103–122%. The assay correlated well (r2 = 0.98; n = 37) with a laboratory-based immunoassay, although mean (SD) results were 7 (29)% lower. Conclusions: The speed and ease of performance of this assay recommend it for near-patient use. The assay is the first to combine a fluorescence resonance energy transfer-type rapid competitive assay with an all-in-one dry reagent.

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Rapid Detection of Norovirus Using Paper-based Microfluidic Device

10.1101/162396 ◽

2017 ◽

Cited By ~ 1

Author(s):

Xuan Weng ◽

Suresh Neethirajan

Keyword(s):

Microfluidic Device ◽

Point Of Care ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Cost Effective ◽

Quantitative Detection ◽

Multi Walled Carbon Nanotubes ◽

Low Sensitivity ◽

Walled Carbon Nanotubes ◽

Analytical Approaches

AbstractNoroviruses (NoV) are the leading cause of outbreak of acute gastroenteritis worldwide. A substantial effort has been made in the development of analytical devices for rapid and sensitive food safety monitoring via the detection of foodborne bacteria, viruses and parasites. Conventional analytical approaches for noroviruses suffer from some critical weaknesses: labor-intensive, time-consuming, and relatively low sensitivity. In this study, we developed a rapid and highly sensitive biosensor towards point-of-care device for noroviruses based on 6-carboxyfluorescein (6-FAM) labeled aptamer and nanomaterials, multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO). In an assay, the fluorescence of 6-FAM labeled aptamer was quenched by MWCNTs or GO via fluorescence resonance energy transfer (FRET). In the presence of norovirus, the fluorescence would be recovered due to the release of the 6-FAM labeled aptamer from MWCNTs or GO. An easy-to-make paper-based microfluidic platform made by nitrocellulose membrane was used to conduct the assay. The quantitative detection of norovirus virus-like particles (NoV VLPs) was successfully performed. A linear range of 0-12.9 μg/mL with a detection limit of 40 pM and 30 pM was achieved for the MWCNTs and GO based paper sensors, respectively. The results suggested the developed paper-based microfluidic device is simple, cost-effective and holds the potential of rapid in situ visual determination for noroviruses with remarkable sensitivity and specificity, which provides a new way for early identification of NoV and thereby an early intervention for preventing the spread of an outbreak.

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Structural dynamics of P-type ATPase ion pumps

Biochemical Society Transactions ◽

10.1042/bst20190124 ◽

2019 ◽

Vol 47 (5) ◽

pp. 1247-1257 ◽

Cited By ~ 17

Author(s):

Mateusz Dyla ◽

Sara Basse Hansen ◽

Poul Nissen ◽

Magnus Kjaergaard

Keyword(s):

Structural Dynamics ◽

Single Molecule ◽

New Technologies ◽

Atp Hydrolysis ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Time Resolved ◽

Dynamics Simulations ◽

Types Of Information ◽

P Type

Abstract P-type ATPases transport ions across biological membranes against concentration gradients and are essential for all cells. They use the energy from ATP hydrolysis to propel large intramolecular movements, which drive vectorial transport of ions. Tight coordination of the motions of the pump is required to couple the two spatially distant processes of ion binding and ATP hydrolysis. Here, we review our current understanding of the structural dynamics of P-type ATPases, focusing primarily on Ca2+ pumps. We integrate different types of information that report on structural dynamics, primarily time-resolved fluorescence experiments including single-molecule Förster resonance energy transfer and molecular dynamics simulations, and interpret them in the framework provided by the numerous crystal structures of sarco/endoplasmic reticulum Ca2+-ATPase. We discuss the challenges in characterizing the dynamics of membrane pumps, and the likely impact of new technologies on the field.

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