Portable Simultaneous Multiple Analyte Whole-Blood Analyzer for Point-of-Care Testing

1992 ◽  
Vol 38 (9) ◽  
pp. 1665-1670 ◽  
Author(s):  
C T Schembri ◽  
V Ostoich ◽  
P J Lingane ◽  
T L Burd ◽  
S N Buhl

Abstract We describe a portable clinical chemistry analyzer for point-of-care measurements of multiple analytes in less than 10 min from approximately 40 microL of whole blood (fingerstick or venous). Whole blood is applied directly to a 7.9-cm-diameter, single-use plastic rotor containing liquid diluent and greater than or equal to 4-12 tests in the form of 1- to 2-mm-diameter dry reagent beads. The reagent/rotor is immediately placed in a portable instrument along with a ticket/label results card. As the instrument spins the rotor, capillary and rotational forces process the blood into diluted plasma, distribute the patient's diluted sample to cuvettes containing the reagent beads, and mix the diluted sample with the reagents. The instrument monitors the chemical reactions optically at nine wavelengths; sample volume and temperature are also measured optically. The calibration data for each reagent are read from a bar code on the periphery of each rotor. The instrument processes all the measurements to calculate, store, print, and communicate the results. Each reagent/rotor contains an enzymatic control that must be within a defined range before the results from that analysis are reported.

2021 ◽  
pp. 104063872110018
Author(s):  
Justin R. Perrault ◽  
Michael D. Arendt ◽  
Jeffrey A. Schwenter ◽  
Julia L. Byrd ◽  
Kathryn A. Tuxbury ◽  
...  

Blood glucose measurements provide important diagnostic information regarding stress, disease, and nutritional status. Glucose analytical methodologies include dry chemistry analysis (DCA) of plasma and point-of-care (POC) glucometer analysis of whole blood; however, these 2 methods differ in cost, required sample volume, and processing time. Because POC glucometers use built-in equations based on features of mammalian blood to convert whole blood measurements to plasma equivalent units, obtained glucose data must be compared and validated using gold-standard chemistry analytical methodology in reptiles. For in-water, trawl-captured, immature Kemp’s ridley sea turtles ( Lepidochelys kempii) from Georgia, USA, we observed significant, positive agreement between the 2 glucose determination methods; however, the glucometer overestimated glucose concentrations by 1.4 mmol/L on average in comparison to DCA and produced a wider range of results. The discordance of these results suggests that POC glucometer glucose data should be interpreted in the context of methodology- and brand-specific reference intervals along with concurrent packed cell volume data.


1995 ◽  
Vol 17 (3) ◽  
pp. 99-104 ◽  
Author(s):  
C. T. Schembri ◽  
T. L. Burd ◽  
A. R. Kopf-Sill ◽  
L. R. Shea ◽  
B. Braynin

A unique clinical chemistry analyser is described which processes 90 μl of whole blood (fingerstick or venous) into multiple aliquots of diluted plasma and reports the results of 12 tests in 14 min. To perform a panel of tests, the operator applies the unmetered sample directly into a single use, 8 cm diameter plastic rotor which contains the required liquid diluent and dry reagents. Using centrifugal and capillary forces, the rotor meters the required amount of blood, separates the red cells, meters the plasma, meters the diluent, mixes the fluids, distributes the fluid to the reaction cuvettes and mixes the reagents and the diluted plasma in the cuvettes. The instrument monitors the reagent reactions simultaneously using nine wavelengths, calculates the results from the absorbance data, and reports the results.


2020 ◽  
Author(s):  
Uroš Zupančič ◽  
Pawan Jolly ◽  
Pedro Estrela ◽  
Despina Moschou ◽  
Donald E. Ingber

ABSTRACTSepsis is a leading cause of mortality worldwide that is difficult to diagnose and manage because this requires simultaneous analysis of multiple biomarkers. Electrochemical detection methods could potentially provide a way to accurately quantify multiple sepsis biomarkers in a multiplexed manner as they have very low limits of detection and require minimal sensor instrumentation; however, affinity-based electrochemical sensors are usually hampered by biological fouling. Here we describe development of an electrochemical detection platform that enables detection of multiple sepsis biomarkers simultaneously by incorporating a recently developed nanocomposite coating composed of crosslinked bovine serum albumin containing a network of reduced graphene oxide nanoparticles that prevents biofouling. Using nanocomposite coated planar gold electrodes, we constructed a procalcitonin sensor and demonstrated sensitive PCT detection in undiluted serum and clinical samples, as well as excellent correlation with a conventional ELISA (adjusted r2 = 0.95). Sensors for two additional sepsis biomarkers — C-reactive protein and pathogen-associated molecular patterns — were developed on the same multiplexed platform and tested in whole blood. Due to the excellent antifouling properties of the nanocomposite coating, all three sensors exhibited specific responses within the clinically significant range without any cross-reactivity in the same channel with low sample volume. This platform enables sensitive simultaneous electrochemical detection of multiple analytes in human whole blood, which can be expanded further to any target analyte with an appropriate antibody pair or capturing probe, and thus, may offer a potentially valuable tool for development of clinical point-of-care diagnostics.GRAPHICAL ABSTRACT


Biosensors ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 73 ◽  
Author(s):  
Vikram Surendran ◽  
Thomas Chiulli ◽  
Swetha Manoharan ◽  
Stephen Knisley ◽  
Muthukumaran Packirisamy ◽  
...  

The integration of microfluidics with advanced biosensor technologies offers tremendous advantages such as smaller sample volume requirement and precise handling of samples and reagents, for developing affordable point-of-care testing methodologies that could be used in hospitals for monitoring patients. However, the success and popularity of point-of-care diagnosis lies with the generation of instantaneous and reliable results through in situ tests conducted in a painless, non-invasive manner. This work presents the development of a simple, hybrid integrated optical microfluidic biosensor for rapid detection of analytes in test samples. The proposed biosensor works on the principle of colorimetric optical absorption, wherein samples mixed with suitable chromogenic substrates induce a color change dependent upon the analyte concentration that could then be detected by the absorbance of light in its path length. This optical detection scheme has been hybrid integrated with an acoustofluidic micromixing unit to enable uniform mixing of fluids within the device. As a proof-of-concept, we have demonstrated the real-time application of our biosensor format for the detection of potassium in whole saliva samples. The results show that our lab-on-a-chip technology could provide a useful strategy in biomedical diagnoses for rapid analyte detection towards clinical point-of-care testing applications.


2016 ◽  
Vol 1 (1) ◽  
pp. 67-76 ◽  
Author(s):  
Robert D Nerenz ◽  
Jennifer R Bell ◽  
Nancy Montes de Oca ◽  
Joann Short ◽  
Theresa Mims ◽  
...  

Abstract Background Point-of-care (POC) urine qualitative human chorionic gonadotropin (hCG) devices are used to rapidly assess pregnancy status, but many of these devices are susceptible to false-negative results caused by increased concentrations of hCG β core fragment (hCGβcf) that does not contain hCGβcf. Methods Purified hCG was added to hCG-negative heparinized whole blood to generate samples with known hCG concentrations, and the resulting samples were used to evaluate device sensitivity, low-end reproducibility, high-dose hook effect, intermediate range performance, acceptable sample volume, acceptable hematocrit range, and lot-to-lot variation. Device performance was also prospectively evaluated in 40 pregnant and 40 nonpregnant women aged 18–44 years in a hospital-based clinic or an academic hospital emergency department. Results All device observations were positive using a whole blood sample containing a plasma hCG concentration of 2.2 × 106 IU/L, and all device observations were positive from18 IU/L to 1.2 × 103 IU/L and from 2.5 × 104 IU/L to 2.2 × 106 IU/L. Three invalid results were observed in the intermediate range because of decreased control line intensity. The minimum sample volume was 30 μL, and maximum hematocrit was 46%. In 40 pregnant and 40 nonpregnant women aged 18–44 years, the device generated 100% concordance with urine qualitative and plasma quantitative test results. Conclusions The ADEXUSDx™ hCG test demonstrates acceptable performance for the determination of pregnancy status using capillary fingerstick samples.


1999 ◽  
Vol 45 (9) ◽  
pp. 1676-1678 ◽  
Author(s):  
Donald E Brooks ◽  
Dana V Devine ◽  
Paul C Harris ◽  
Joanne E Harris ◽  
Mark E Miller ◽  
...  

Author(s):  
Hyung-Doo Park

Context.— The clinical applications of point-of-care testing (POCT) are gradually increasing in many health care systems. Recently, POCT devices using molecular genetic method techniques have been developed. We need to examine clinical pathways to see where POCT can be applied to improve them. Objective.— To introduce up-to-date POCT items and equipment and to provide the content that should be prepared for clinical application of POCT. Data Sources.— Literature review based on PubMed searches containing the terms point-of-care testing, clinical chemistry, diagnostic hematology, and clinical microbiology. Conclusions.— If medical resources are limited, POCT can help clinicians make quick medical decisions. As POCT technology improves and menus expand, areas where POCT can be applied will also increase. We need to understand the limitations of POCTs so that they can be optimally used to improve patient management.


2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S325-S325
Author(s):  
D Maniero ◽  
G Lorenzon ◽  
I Marsilio ◽  
A Rigo ◽  
R Cardin ◽  
...  

Abstract Background Infliximab (IFX) is a monoclonal antibody that targets cytokine tumor necrosis factor; it is used for the treatment of patients with active inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC). IFX induces and maintains remission and mucosal healing in patients with IBD. Measurement of trough levels (TL) of IFX is important to assess if the drug is within its therapeutic concentrationand to explain lack/loss of response. Standard laboratory tests to assess IFX trough levels (enzyme linked immunosorbent assays, ELISA) present some downsides, related to the long turnaround (about 3 hours), and the need of specialized equipment and laboratory personnel. For this reason, point-of care testing (POCT) was developed to provide results within a few minutes from blood collection, leading to a decision-making approach. Aim To determine the degree of analytical correlation between a recently developed POCT (ProciseDx) IFX assay which analyze capillary whole blood and the comparative ELISA from serum. Methods From October 2020 to January 2021, patients (aged≥18 years) taking IFX were recruited at Gastroenterology Unit, Padua University Hospital. In each patient, IFX levels from capillary whole blood collected by finger stick were performed using the ProciseDx IFX assay with reportable range between 1.7-77.2 µg/mL; at the same time, a serum sample from venous blood was collected to carry out Grifols’ Promonitor ELISA test (range 0.035–14.4 µg/mL). A Deming regression test was used to identify the correlation between the two methods. Results Eighty-seven patients were enrolled (63% males; mean age of 44±16), with 52% of them having CD, 45% UC and 3% an undetermined-Inflammatory Bowel Disease. The assessment with ProciseDx POCT was feasible in each patient and only in three cases blood collection from finger prick was repeated. Moreover, from blood collection to results we needed about 3±0.5 minutes, while serum ELISA analysis required the collection of at least 40 samples (around three weeks at our centre) and 3 hours to be performed. 39 patients (59% males; mean age of 44±16) had TL as assessed by ProciseDx IFX assay lower than 1.7 or greater than 14.4 µg/mL, in accordance with ELISA assessment. Among the remaining 48 patients (67% males with mean age of 45±17), The correlation between the two tests was high (the total results showed an R squared of 0.691 (95% CI 0.717-0.902). Conclusion The ProciseDx POCT has good accuracy but was more rapid and easy to be performed in providing the results of Therapeutic Drug Monitoring in outpatients taking IFX. This could lead to a more effective optimization of the biological drug, thus avoiding treatment failure.


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