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Background Cardiac troponin (cTn) has been broadly accepted as the biomarker of choice in the diagnosis of patients presenting with Acute Coronary Syndrome (ACS). Point-of-care (POC) cTn testing, defined as testing near the patient with rapid availability of results, has attracted a strong interest in the emergency department (ED) setting. It offers the potential to improve workflows, expedite clinical decisions and to reduce the length of stay. Workflows could be further optimized when a first measurement can already be performed by the emergency medical services prior to admission to the hospital. Advances in assay technology have led to high sensitive (HS) cTn assays that have a profound impact on clinical practice, providing early results at presentation and 1 hour after admission which speed up clinical decision-making. Here we evaluate the Minicare HS cTnI POC test under development, which has the potential to combine the benefits of HS-cTnI protocols with a POC workflow. Objective Evaluate the analytical and clinical capability of the Minicare HS-cTnI test under development to meet the criteria‡ for HS cTn of having a 10% CV LoD) of >50%. Methods The evaluation is based on the Clinical Laboratory Standards Institute (CLSI) guidelines. Li-heparin whole blood and Li-heparin plasma samples were used to establish LoB, LoD, and LoQ, sample matrix comparison and linearity in the low range. The clinical performance for Minicare HS-cTnI was assessed and compared to Abbott Architect high-sensitivity troponin using banked samples from patients with ACS and collected at t=2–4h after admission. The percentage measurable was assessed and compared to Abbott Architect high-sensitivity troponin in a healthy population of 165 individuals. Results With a time to result within 10 minutes, the LoB is determined at 1.0 ng/L and the LoD at 2.1 ng/L. Plasma and whole blood results correlated well and showed comparable results. The 10% and 20% CV LoQ are established at 7.9 ng/L and 3.1 ng/L, well below the anticipated 99th percentile of 26 ng/L. With a percentage measurable of 77%, the criteria for a HS-cTnI assay are met in a POC device. A sensitivity of 93% and an NPV of 99% are found for Minicare HS-cTnI for a t=2–4h protocol vs 90% and 98% for Abbott Architect high-sensitivity troponin. In this study the area under the curve is 0.98 for Minicare HS-cTnI and 0.97 for Architect HS-cTnI. ROC curve t=2-4 h Conclusions With HS-cTnI capability on the Minicare platform, we show the potential to support a 0/1 h sampling protocol, combined with the speed of a POC workflow. This may enable even more rapid and safe rule-out of patients with ACS.

Background Capillary B-type natriuretic peptide (BNP) testing is attractive in outpatient and emergency settings. The aim of this study was to perform an evaluation of the clinical performances of capillary BNP testing as compared with venous whole blood and plasma point-of-care (POC) BNP as well as plasma N-terminal (NT) proBNP central laboratory testing. Methods BNP was measured with a novel single epitope POC assay (Minicare® BV, Eindhoven, The Netherlands) and NT-proBNP with a central laboratory assay (Roche Diagnostics®, Vienna, Austria). Results BNP and NT-proBNP were measured in 269 patients of a Department of Cardiology (mean age 67.9 ± 13 years, 26.4% females). Capillary BNP very closely correlated with whole blood venous BNP (r = 0.99, p Conclusions Our study for the first time demonstrated a very close correlation of capillary and venous whole blood or plasma BNP concentrations using the same BNP assay in a large patient cohort. The diagnostic performances of different BNP specimens did not differ significantly, and no significant differences between BNP and NT-proBNP were found either.

OBJECTIVES: Point-of-care cardiac troponin testing with adequate analytical performances has the potential to improve chest pain patients flow in the emergency department. We present the analytical evaluation of the newly developed Philips Minicare cTnI point-of-care immunoassay. DESIGN & METHODS: Li-heparin whole blood and plasma were used to perform analytical studies. The sample type comparison study was performed at 4 different hospitals. The 99th percentile upper reference limit (URL) study was performed using Li-heparin plasma, Li-heparin whole blood and capillary blood samples from 750 healthy adults, aging from 18 to 86years. RESULTS: Limit of the blank, limit of detection and limit of quantitation at 20% coefficient of variation (CV) were determined to be 8.5ng/L, 18ng/L and 38ng/L respectively without significant differences between whole blood and plasma for LoQ. Cross-reactivity and interferences were minimal and no high-dose hook was observed. Total CV was found to be from 7.3% to 12% for cTnI concentrations between 109.6 and 6135.4ng/L. CV at the 99th percentile URL was 18.6%. The sample type comparison study between capillary blood, Li-heparin whole blood and Li-heparin plasma samples demonstrated correlation coefficients between 0.99 and 1.00 with slopes between 1.03 and 1.08. The method comparison between Minicare cTnI and Beckman Coulter Access, AccuTnI+3 demonstrated a correlation coefficient of 0.973 with a slope of 1.09. The 99th percentile URL of a healthy population was calculated to be 43ng/L with no significant difference between genders or sample types. CONCLUSIONS: The Minicare cTnI assay is a sensitive and precise, clinical usable test for determination of cTnI concentration that can be used in a near-patient setting as an aid in the diagnosis of acute myocardial infarction. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Point-of-care B-type natriuretic peptide (BNP) testing with adequate analytical performance has the potential to improve patient flow and provide primary care givers with easy-to-use advanced diagnostic tools in the management of heart failure. We present the analytical evaluation of the Minicare BNP immunoassay under development on the Minicare I-20 platform for point-of-care testing. Analytical performance was evaluated using EDTA venous whole blood, EDTA plasma and capillary whole blood. Method comparison with a lab-testing system was performed using samples from 187 patients. Normal values were determined based on 160 healthy adults, aging from 19 to 70 years. Limit of blank (LoB), limit of detection (LoD) were determined to be 3.3 ng/L, 5.8 ng/L. Limit of quantitation (LoQ) in whole blood at 20% and 10% coefficient of variation (CV) was found

We describe an analysis of the dynamics of individual superparamagnetic micro- and nanoparticles in order to quantify their magnetic properties and mobility near a chip surface. The particles are attracted to the chip surface by integrated microscopic current wires. We show that it is possible to accurately analyze particles with a diameter of about 1 µm by the magnetophoretic movement between current wires because of the very high field gradients. This reveals distinct differences in volume susceptibilities of particles with the same outer diameter. Smaller particles are characterized using the technique of confined Brownian motion analysis. By capturing 300 nm particles on a current wire with surface barriers or a focused shape, the magnetization of the particles can be measured with an accuracy better than 10%.

The realization of biomolecular detection assays for diagnostic purposes is technologically very challenging because such tests demand full integration for ease of use and need to deliver a high analytical performance with cost-effective use of materials. In this article an optomagnetic immunoassay technology is described based on nanoparticles that are magnetically actuated and optically detected in a stationary sample fluid. The dynamic control of nanoparticles by magnetic fields impacts the key immunoassay process steps, giving unprecedented speed, assay control and seamless integration of the total test. The optical detection yields sensitive and multiplexed assays in a low-cost disposable cartridge. We demonstrate that the optomagnetic technology enables high-sensitivity one-step assays in blood serum/plasma and whole saliva. Drugs of abuse are detected at sub-nanogram per millilitre levels in a total assay time of 1 min, and the cardiac marker troponin I is detected at sub-picomole per litre concentrations in a few minutes. The optomagnetic technology is fundamentally suited for high-performance integrated testing and is expected to open a new paradigm in biosensing.

An increasing number of biomedical applications requires detailed knowledge of the magnetic susceptibility of individual particles. With conventional techniques it is very difficult to analyze individual particles smaller than 1 µm. The authors demonstrate how the susceptibility of individual nanoparticles can be determined in an efficient way by optically analyzing the confined Brownian motion of a nanoparticle trapped in a known magnetic potential well on a chip. A setup is introduced that has a controllable two-dimensional magnetic potential well, which is defined by an integrated microscopic current wire. Susceptibility measurements have been performed on 150–450 nm superparamagnetic beads. They found differences in bead susceptibility of an order of magnitude and differences in volumetric susceptibility of more than a factor of 2.

Background Intraoperative parathyroid hormone (ioPTH) is used during minimally invasive parathyroidectomy (MIP) to predict the success of surgery and should be accurate with a short turnaround time. Material and method We developed an ioPTH point-of-care (POC) assay on Philips handheld magnotech system. Magnotech technology is based on magnetically controlled movement of superparamagnetic nanoparticles in stationary sample fluid. During first phase, intact-PTH is captured by magnetic particles coated with anti-N-terminal-PTH antibodies. Subsequently, magnetic particles are collected by magnetic forces at sensor surface coated with anti-C-terminal-PTH antibodies. Unbound/nonspecifically bound particles are pulled away from detection surface, using a second magnetic force. Amount of specifically bound particles is measured using a surface-sensitive optical imaging technique. Results ioPTH test could be performed with a turnaround time of less than 10 min and could detect low intact-PTH concentrations (picomolar). Integrated cartridge contains a blood separation filter and dry reagents for the assay. Conclusion The next magnotech ioPTH assay will be the only POC test able to give accurate results in less than 10 min, using 25 μL of whole blood. Thanks to the ease-of-use, magnotech ioPTH could be performed in the operating theater by any member of surgical staff.