1
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Kinnamon DS, Heggestad JT, Liu J, Nguyen T, Ly V, Hucknall AM, Fontes CM, Britton RJ, Cai JP, Chan JFW, Yuen KY, Le T, Chilkoti A. Environmentally Resilient Microfluidic Point-of-Care Immunoassay Enables Rapid Diagnosis of Talaromycosis. ACS Sens 2023; 8:2228-2236. [PMID: 37279466 PMCID: PMC10449026 DOI: 10.1021/acssensors.3c00209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Point-of-care tests (POCTs) are increasingly being used in field settings, particularly outdoors. The performance of current POCTs─most commonly the lateral flow immunoassay─can be adversely affected by ambient temperature and humidity. We developed a self-contained immunoassay platform─the D4 POCT─that can be conducted at the POC by integrating all reagents in a capillary-driven passive microfluidic cassette that minimizes user intervention. The assay can be imaged and analyzed on a portable fluorescence reader─the D4Scope─and provide quantitative outputs. Here, we systematically investigated the resilience of our D4 POCT to varied temperature and humidity and to physiologically diverse human whole blood samples that span a wide range of physiological hematocrit (30-65%). For all conditions, we showed that the platform maintained high sensitivity (0.05-0.41 ng/mL limits of detection). The platform also demonstrated good accuracy in reporting true analyte concentration across environmental extremes when compared to the manually operated format of the same test to detect a model analyte─ovalbumin. Additionally, we engineered an improved version of the microfluidic cassette that improved the ease-of-use of the device and shortened the time-to-result. We implemented this new cassette to create a rapid diagnostic test to detect talaromycosis infection in patients with advanced HIV disease at the POC, demonstrating comparable sensitivity and specificity to the laboratory test for the disease.
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Affiliation(s)
- David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Thu Nguyen
- Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, North Carolina 27708, United States
| | - Vo Ly
- Hospital for Tropical Disease, Ho Chi Minh City 73009, Vietnam
- University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City 72714, Vietnam
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Rhett J Britton
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
| | - Jian-Piao Cai
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam 000000, Hong Kong
| | - Jasper Fuk-Woo Chan
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam 000000, Hong Kong
- Hainan Medical University─The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases, Hainan Medical University, Haikou 571101, Hainan, China
| | - Kwok-Yung Yuen
- State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam 000000, Hong Kong
- Hainan Medical University─The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases, Hainan Medical University, Haikou 571101, Hainan, China
| | - Thuy Le
- Division of Infectious Diseases and International Health, Duke University School of Medicine, Durham, North Carolina 27708, United States
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, North Carolina 27708, United States
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2
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Heggestad JT, Britton RJ, Kinnamon DS, Liu J, Anderson JG, Joh DY, Quinn Z, Fontes CM, Hucknall AM, Parks R, Sempowski GD, Denny TN, Burke TW, Haynes BF, Woods CW, Chilkoti A. COVID-19 Diagnosis and SARS-CoV-2 Strain Identification by a Rapid, Multiplexed, Point-of-Care Antibody Microarray. Anal Chem 2023; 95:5610-5617. [PMID: 36961989 PMCID: PMC10068875 DOI: 10.1021/acs.analchem.2c05180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 03/17/2023] [Indexed: 03/26/2023]
Abstract
Antigen tests to detect SARS-CoV-2 have emerged as a promising rapid diagnostic method for COVID-19, but they are unable to differentiate between variants of concern (VOCs). Here, we report a rapid point-of-care test (POC-T), termed CoVariant-SPOT, that uses a set of antibodies that are either tolerant or intolerant to spike protein mutations to identify the likely SARS-CoV-2 strain concurrent with COVID-19 diagnosis using antibodies targeting the nucleocapsid protein. All reagents are incorporated into a portable, multiplexed, and sensitive diagnostic platform built upon a nonfouling polymer brush. To validate CoVariant-SPOT, we tested recombinant SARS-CoV-2 proteins, inactivated viruses, and nasopharyngeal swab samples from COVID-19 positive and negative individuals and showed that CoVariant-SPOT can readily distinguish between two VOCs: Delta and Omicron. We believe that CoVariant-SPOT can serve as a valuable adjunct to next-generation sequencing to rapidly identify variants using a scalable and deployable POC-T, thereby enhancing community surveillance efforts worldwide and informing treatment selection.
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Affiliation(s)
- Jacob T. Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Rhett J. Britton
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - David S. Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Jack G. Anderson
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Daniel Y. Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Zachary Quinn
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Cassio M. Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Angus M. Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Robert Parks
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Gregory D. Sempowski
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Thomas N. Denny
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Thomas W. Burke
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Immunology, Duke University School of Medicine, Durham, NC, USA
| | - Christopher W. Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
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3
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Ozer I, Kelly G, Gu R, Li X, Zakharov N, Sirohi P, Nair SK, Collier JH, Hershfield MS, Hucknall AM, Chilkoti A. Polyethylene Glycol-Like Brush Polymer Conjugate of a Protein Drug Does Not Induce an Antipolymer Immune Response and Has Enhanced Pharmacokinetics than Its Polyethylene Glycol Counterpart. Adv Sci (Weinh) 2022; 9:e2103672. [PMID: 35133079 PMCID: PMC9008788 DOI: 10.1002/advs.202103672] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/04/2021] [Indexed: 05/13/2023]
Abstract
Protein therapeutics, except for antibodies, have a short plasma half-life and poor stability in circulation. Covalent coupling of polyethylene glycol (PEG) to protein drugs addresses this limitation. However, unlike previously thought, PEG is immunogenic. In addition to induced PEG antibodies, ≈70% of the US population has pre-existing anti-PEG antibodies. Both induced and preexisting anti-PEG antibodies result in accelerated drug clearance, reduced clinical efficacy, and severe hypersensitivity reactions that have limited the clinical utility of uricase, an enzyme drug for treatment for refractory gout that is decorated with a PEG corona. Here, the authors synthesize a poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) conjugate of uricase that decorates the protein with multiple polymer chains to create a corona to solve these problems. The resulting uricase-POEGMA is well-defined, has high bioactivity, and outperforms its PEG counterparts in its pharmacokinetics (PK). Furthermore, the conjugate does not induce anti-POEGMA antibodies and is not recognized by anti-PEG antibodies. These findings suggest that POEGMA conjugation may provide a solution to the immunogenicity and antigenicity limitations of PEG while improving upon its PK benefits. These results transcend uricase and can be applied to other PEGylated therapeutics and the broader class of biologics with suboptimal PK.
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Affiliation(s)
- Imran Ozer
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Garrett Kelly
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Renpeng Gu
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Xinghai Li
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Nikita Zakharov
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Parul Sirohi
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Smita K. Nair
- Department of SurgeryDuke University School of MedicineDurhamNC27710USA
| | - Joel H. Collier
- Department of Biomedical EngineeringDuke UniversityDurhamNC27708USA
| | - Michael S. Hershfield
- Department of MedicineDivision of RheumatologyDuke University Medical CenterDurhamNC27710USA
- Department of BiochemistryDuke University School of MedicineDurhamNC27710USA
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4
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Ozer I, Pitoc GA, Layzer JM, Moreno A, Olson LB, Layzer KD, Hucknall AM, Sullenger BA, Chilkoti A. PEG-Like Brush Polymer Conjugate of RNA Aptamer That Shows Reversible Anticoagulant Activity and Minimal Immune Response. Adv Mater 2022; 34:e2107852. [PMID: 34994037 DOI: 10.1002/adma.202107852] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Ribonucleic acid (RNA) therapeutics are an emerging class of drugs. RNA aptamers are of significant therapeutic and clinical interest because their activity can be easily reversed in vivo-a useful feature that is difficult to achieve using other therapeutic modalities. Despite their therapeutic promise, RNA aptamers are limited by their poor blood circulation. The attachment of polyethylene glycol (PEG) to RNA aptamers addresses this limitation. However, an RNA aptamer-PEG conjugate that is a reversible anticoagulant fails in a clinical trial due to the reactivity of the conjugate with pre-existing PEG antibodies and has cast a pall over PEGylation of aptamers and other biologics, despite its long history of utility in drug delivery. Here, PEG antibody-reactivity of this RNA aptamer is eliminated by conjugating it to a next-generation PEG-like brush polymer-poly[(oligoethylene glycol) methyl ether methacrylate)] (POEGMA). The conjugate retained the drug's therapeutic action and the ability to be easily reversed. Importantly, this conjugate does not bind pre-existing PEG antibodies that are prevalent in humans and does not induce a humoral immune response against the polymer itself in mice. These findings suggest a path to rescuing the PEGylation of RNA therapeutics and vaccines from the deleterious side-effects of PEG.
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Affiliation(s)
- Imran Ozer
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - George A Pitoc
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Juliana M Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
- Duke Clinical and Translational Science Institute, Durham, NC, 27707, USA
| | - Angelo Moreno
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Lyra B Olson
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Kyle D Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
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5
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Heggestad JT, Kinnamon DS, Liu J, Joh DY, Fontes CM, Wei Q, Ozcan A, Hucknall AM, Chilkoti A. Smartphone Enabled Point-of-Care Detection of Serum Biomarkers. Methods Mol Biol 2022; 2393:343-365. [PMID: 34837189 DOI: 10.1007/978-1-0716-1803-5_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Sandwich immunoassays are the gold standard for detection of protein analytes. Here, we describe an ultrasensitive point-of-care sandwich immunoassay platform for the detection of biomarkers directly from blood or serum using a custom-built smartphone detector. Testing undiluted blood or serum is challenging due to the complexity of the matrix. Proteins nonspecifically adsorb to and cells often adhere to the assay surface, which can drastically impact the analytical sensitivity of the assay. To address this problem, our assay is built upon a "nonfouling" polymer brush "grafted from" a glass slide, which eliminates nearly all nonspecific binding and therefore increases the signal-to-noise ratio and greatly improves the analytical performance of the test. The two components required to perform a sandwich immunoassay are inkjet-printed directly onto the surface: (1) "stable" capture antibodies that remain entrapped in the brush even after exposure to a liquid sample and (2) fluorescently labeled "soluble" detection antibodies that dissolve upon exposure to a liquid sample. The polymer brush provides hydration to the antibodies, allowing them to remain stable and active over prolonged periods of time. When a liquid sample containing a biomarker of interest is dispensed onto the chip, the detection antibodies dissolve and diffuse to the stable capture spots forming a complex that sandwiches the analyte and that has a fluorescence intensity proportional to the concentration of the biomarker in solution, which can be measured using a custom-built smartphone detector. As multiple capture antibodies can be printed as discrete capture spots, the assay can be easily multiplexed without the need for multiple fluorophores. This chip and detector platform can be utilized for the point-of-care detection of low-abundance biomarkers directly from blood or serum in low-resource settings.
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Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
| | - Qingshan Wei
- Department of Chemical and Biomolecular Engineering, College of Engineering, NC State University, Raleigh, NC, USA
| | - Aydogan Ozcan
- Electrical and Computer Engineering and Bioengineering Departments, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, CA, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA.
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA.
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6
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Heggestad JT, Britton RJ, Kinnamon DS, Wall SA, Joh DY, Hucknall AM, Olson LB, Anderson JG, Mazur A, Wolfe CR, Oguin TH, Sullenger BA, Burke TW, Kraft BD, Sempowski GD, Woods CW, Chilkoti A. Rapid test to assess the escape of SARS-CoV-2 variants of concern. Sci Adv 2021; 7:eabl7682. [PMID: 34860546 PMCID: PMC8641938 DOI: 10.1126/sciadv.abl7682] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/15/2021] [Indexed: 05/03/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are concerning in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Here, we developed a rapid test, termed CoVariant-SCAN, that detects neutralizing antibodies (nAbs) capable of blocking interactions between the angiotensin-converting enzyme 2 receptor and the spike protein of wild-type (WT) SARS-CoV-2 and three other variants: B.1.1.7, B.1.351, and P.1. Using CoVariant-SCAN, we assessed neutralization/blocking of monoclonal antibodies and plasma from COVID-19–positive and vaccinated individuals. For several monoclonal antibodies and most plasma samples, neutralization against B.1.351 and P.1 variants is diminished relative to WT, while B.1.1.7 is largely cross-neutralized. We also showed that we can rapidly adapt the platform to detect nAbs against an additional variant—B.1.617.2 (Delta)—without reengineering or reoptimizing the assay. Results using CoVariant-SCAN are consistent with live virus neutralization assays and demonstrate that this easy-to-deploy test could be used to rapidly assess nAb response against multiple SARS-CoV-2 variants.
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Affiliation(s)
- Jacob T. Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Rhett J. Britton
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - David S. Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Simone A. Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Daniel Y. Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Angus M. Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Lyra B. Olson
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jack G. Anderson
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Anna Mazur
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Cameron R. Wolfe
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Thomas H. Oguin
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Bruce A. Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Thomas W. Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Gregory D. Sempowski
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Christopher W. Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
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7
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Heggestad JT, Kinnamon DS, Olson LB, Liu J, Kelly G, Wall SA, Oshabaheebwa S, Quinn Z, Fontes CM, Joh DY, Hucknall AM, Pieper C, Anderson JG, Naqvi IA, Chen L, Que LG, Oguin T, Nair SK, Sullenger BA, Woods CW, Burke TW, Sempowski GD, Kraft BD, Chilkoti A. Multiplexed, quantitative serological profiling of COVID-19 from blood by a point-of-care test. Sci Adv 2021; 7:eabg4901. [PMID: 34172447 PMCID: PMC8232907 DOI: 10.1126/sciadv.abg4901] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 05/12/2021] [Indexed: 05/08/2023]
Abstract
Highly sensitive, specific, and point-of-care (POC) serological assays are an essential tool to manage coronavirus disease 2019 (COVID-19). Here, we report on a microfluidic POC test that can profile the antibody response against multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens-spike S1 (S1), nucleocapsid (N), and the receptor binding domain (RBD)-simultaneously from 60 μl of blood, plasma, or serum. We assessed the levels of antibodies in plasma samples from 31 individuals (with longitudinal sampling) with severe COVID-19, 41 healthy individuals, and 18 individuals with seasonal coronavirus infections. This POC assay achieved high sensitivity and specificity, tracked seroconversion, and showed good concordance with a live virus microneutralization assay. We can also detect a prognostic biomarker of severity, IP-10 (interferon-γ-induced protein 10), on the same chip. Because our test requires minimal user intervention and is read by a handheld detector, it can be globally deployed to combat COVID-19.
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Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Lyra B Olson
- Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Garrett Kelly
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Simone A Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Solomon Oshabaheebwa
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Zachary Quinn
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Division of Plastic, Maxillofacial, and Oral Surgery, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Carl Pieper
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27708, USA
| | - Jack G Anderson
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Ibtehaj A Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Loretta G Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Thomas Oguin
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Smita K Nair
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Neurosurgery and Pathology, Duke University School of Medicine, Duke University, Durham, NC 27710, USA
| | - Bruce A Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Christopher W Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Thomas W Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Gregory D Sempowski
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Bryan D Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA.
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8
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Heggestad JT, Kinnamon DS, Olson LB, Liu J, Kelly G, Wall SA, Fontes CM, Joh DY, Hucknall AM, Pieper C, Naqvi IA, Chen L, Que LG, Oguin T, Nair SK, Sullenger BA, Woods CW, Sempowski GD, Kraft BD, Chilkoti A. Multiplexed, quantitative serological profiling of COVID-19 from a drop of blood by a point-of-care test. medRxiv 2020:2020.11.05.20226654. [PMID: 33173900 PMCID: PMC7654894 DOI: 10.1101/2020.11.05.20226654] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Highly sensitive, specific, and point-of-care (POC) serological assays are an essential tool to manage the COVID-19 pandemic. Here, we report on a microfluidic, multiplexed POC test that can profile the antibody response against multiple SARS-CoV-2 antigens - Spike S1 (S1), Nucleocapsid (N), and the receptor binding domain (RBD) - simultaneously from a 60 microliter drop of blood, plasma, or serum. We assessed the levels of anti-SARS-CoV-2 antibodies in plasma samples from 19 individuals (at multiple time points) with COVID-19 that required admission to the intensive care unit and from 10 healthy individuals. This POC assay shows good concordance with a live virus microneutralization assay, achieved high sensitivity (100%) and specificity (100%), and successfully tracked the longitudinal evolution of the antibody response in infected individuals. We also demonstrated that we can detect a chemokine, IP-10, on the same chip, which may provide prognostic insight into patient outcomes. Because our test requires minimal user intervention and is read by a handheld detector, it can be globally deployed in the fight against COVID-19 by democratizing access to laboratory quality tests.
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Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Lyra B Olson
- Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710 USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Garrett Kelly
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Simone A Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
- Division of Plastic, Maxillofacial, and Oral Surgery, Department of Surgery, Duke University Medical Center, Durham NC 27710 USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Carl Pieper
- Departments of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27708 USA
| | - Ibtehaj A Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Loretta G Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Thomas Oguin
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
| | - Smita K Nair
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
- Department of Neurosurgery and Pathology, Duke University School of Medicine, Duke University, Durham, NC 27710 USA
| | - Bruce A Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710 USA
| | - Christopher W Woods
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710 USA
| | - Gregory D Sempowski
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
| | - Bryan D Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
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9
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Heggestad JT, Fontes CM, Joh DY, Hucknall AM, Chilkoti A. In Pursuit of Zero 2.0: Recent Developments in Nonfouling Polymer Brushes for Immunoassays. Adv Mater 2020; 32:e1903285. [PMID: 31782843 PMCID: PMC6986790 DOI: 10.1002/adma.201903285] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 10/17/2019] [Indexed: 05/11/2023]
Abstract
"Nonfouling" polymer brush surfaces can greatly improve the performance of in vitro diagnostic (IVD) assays due to the reduction of nonspecific protein adsorption and consequent improvement of signal-to-noise ratios. The development of synthetic polymer brush architectures that suppress adventitious protein adsorption is reviewed, and their integration into surface plasmon resonance and fluorescent sandwich immunoassay formats is discussed. Also, highlighted is a novel, self-contained immunoassay platform (the D4 assay) that transforms time-consuming laboratory-based assays into a user-friendly and point-of-care format with a sensitivity and specificity comparable or better than standard enzyme-linked immunosorbent assay (ELISA) directly from unprocessed samples. These advancements clearly demonstrate the utility of nonfouling polymer brushes as a substrate for ultrasensitive and robust diagnostic assays that may be suitable for clinical testing, in field and laboratory settings.
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Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
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10
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Joh DY, Zimmers Z, Avlani M, Heggestad JT, Aydin HB, Ganson N, Kumar S, Fontes C, Achar RK, Hershfield MS, Hucknall AM, Chilkoti A. Architectural Modification of Conformal PEG-Bottlebrush Coatings Minimizes Anti-PEG Antigenicity While Preserving Stealth Properties. Adv Healthc Mater 2019; 8:e1801177. [PMID: 30908902 PMCID: PMC6819148 DOI: 10.1002/adhm.201801177] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 02/12/2019] [Indexed: 01/18/2023]
Abstract
Poly(ethylene glycol) (PEG), a linear polymer known for its "stealth" properties, is commonly used to passivate the surface of biomedical implants and devices, and it is conjugated to biologic drugs to improve their pharmacokinetics. However, its antigenicity is a growing concern. Here, the antigenicity of PEG is investigated when assembled in a poly(oligoethylene glycol) methacrylate (POEGMA) "bottlebrush" configuration on a planar surface. Using ethylene glycol (EG) repeat lengths of the POEGMA sidechains as a tunable parameter for optimization, POEGMA brushes with sidechain lengths of two and three EG repeats are identified as the optimal polymer architecture to minimize binding of anti-PEG antibodies (APAs), while retaining resistance to nonspecific binding by bovine serum albumin and cultured cells. Binding of backbone- versus endgroup-selective APAs to POEGMA brushes is further investigated, and finally the antigenicity of POEGMA coatings is assessed against APA-positive clinical plasma samples. These results are applied toward fabricating immunoassays on POEGMA surfaces with minimal reactivity toward APAs while retaining a low limit-of-detection for the analyte. Taken together, these results offer useful design concepts to reduce the antigenicity of polymer brush-based surface coatings used in applications involving human or animal matrices.
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Affiliation(s)
- Daniel Y. Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Zackary Zimmers
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Manav Avlani
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Jacob T. Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Hakan B. Aydin
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Nancy Ganson
- Department of Medicine, Division of Rheumatology, Duke University Medical Center, Durham, NC 27710 USA
| | - Shourya Kumar
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Cassio Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Rohan K. Achar
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Michael S. Hershfield
- Department of Medicine, Division of Rheumatology, Duke University Medical Center, Durham, NC 27710 USA
- Department of Biochemistry, Duke University School of Medicine, Durham NC 27710 USA
| | - Angus M. Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham NC 27708 USA
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11
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Joh DY, Hucknall AM, Wei Q, Mason KA, Lund ML, Fontes CM, Hill RT, Blair R, Zimmers Z, Achar RK, Tseng D, Gordan R, Freemark M, Ozcan A, Chilkoti A. Inkjet-printed point-of-care immunoassay on a nanoscale polymer brush enables subpicomolar detection of analytes in blood. Proc Natl Acad Sci U S A 2017; 114:E7054-E7062. [PMID: 28784765 PMCID: PMC5576789 DOI: 10.1073/pnas.1703200114] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The ELISA is the mainstay for sensitive and quantitative detection of protein analytes. Despite its utility, ELISA is time-consuming, resource-intensive, and infrastructure-dependent, limiting its availability in resource-limited regions. Here, we describe a self-contained immunoassay platform (the "D4 assay") that converts the sandwich immunoassay into a point-of-care test (POCT). The D4 assay is fabricated by inkjet printing assay reagents as microarrays on nanoscale polymer brushes on glass chips, so that all reagents are "on-chip," and these chips show durable storage stability without cold storage. The D4 assay can interrogate multiple analytes from a drop of blood, is compatible with a smartphone detector, and displays analytical figures of merit that are comparable to standard laboratory-based ELISA in whole blood. These attributes of the D4 POCT have the potential to democratize access to high-performance immunoassays in resource-limited settings without sacrificing their performance.
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Affiliation(s)
- Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708;
| | - Qingshan Wei
- Electrical Engineering and Bioengineering Departments, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, CA 90095
| | - Kelly A Mason
- Division of Pediatric Endocrinology, Department of Pediatrics, School of Medicine, Duke University, Durham, NC 27705
| | - Margaret L Lund
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Ryan T Hill
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Rebecca Blair
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Zackary Zimmers
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Rohan K Achar
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708
| | - Derek Tseng
- Electrical Engineering and Bioengineering Departments, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, CA 90095
| | - Raluca Gordan
- Center for Genomic and Computational Biology, Duke University, Durham, NC 27708
| | - Michael Freemark
- Division of Pediatric Endocrinology, Department of Pediatrics, School of Medicine, Duke University, Durham, NC 27705
| | - Aydogan Ozcan
- Electrical Engineering and Bioengineering Departments, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, CA 90095
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708;
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12
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Joh DY, McGuire F, Abedini-Nassab R, Andrews JB, Achar RK, Zimmers Z, Mozhdehi D, Blair R, Albarghouthi F, Oles W, Richter J, Fontes CM, Hucknall AM, Yellen BB, Franklin AD, Chilkoti A. Poly(oligo(ethylene glycol) methyl ether methacrylate) Brushes on High-κ Metal Oxide Dielectric Surfaces for Bioelectrical Environments. ACS Appl Mater Interfaces 2017; 9:5522-5529. [PMID: 28117566 DOI: 10.1021/acsami.6b15836] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Advances in electronics and life sciences have generated interest in "lab-on-a-chip" systems utilizing complementary metal oxide semiconductor (CMOS) circuitry for low-power, portable, and cost-effective biosensing platforms. Here, we present a simple and reliable approach for coating "high-κ" metal oxide dielectric materials with "non-fouling" (protein- and cell-resistant) poly(oligo(ethylene glycol) methyl ether methacrylate (POEGMA) polymer brushes as biointerfacial coatings to improve their relevance for biosensing applications utilizing advanced electronic components. By using a surface-initiated "grafting from" strategy, POEGMA films were reliably grown on each material, as confirmed by ellipsometric measurements and X-ray photoelectron spectroscopy (XPS) analysis. The electrical behavior of these POEGMA films was also studied to determine the potential impact on surrounding electronic devices, yielding information on relative permittivity and breakdown field for POEGMA in both dry and hydrated states. We show that the incorporation of POEGMA coatings significantly reduced levels of nonspecific protein adsorption compared to uncoated high-κ dielectric oxide surfaces as shown by protein resistance assays. These attributes, combined with the robust dielectric properties of POEGMA brushes on high-κ surfaces open the way to incorporate this protein and cell resistant polymer interface into CMOS devices for biomolecular detection in a complex liquid milieu.
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Affiliation(s)
- Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Felicia McGuire
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Roozbeh Abedini-Nassab
- Department of Mechanical Engineering and Materials Science, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Joseph B Andrews
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Rohan K Achar
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Zackary Zimmers
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Darush Mozhdehi
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Rebecca Blair
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Faris Albarghouthi
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - William Oles
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Jacob Richter
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Benjamin B Yellen
- Department of Mechanical Engineering and Materials Science, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
| | - Aaron D Franklin
- Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
- Department of Chemistry, Duke University , Durham, North Carolina 27708, United States
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University , Durham, North Carolina 27708, United States
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