{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T15:25:07Z","timestamp":1790004307101,"version":"4.0.1"},"reference-count":39,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,16]],"date-time":"2019-12-16T00:00:00Z","timestamp":1576454400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RF 2017R1D1A1A09000712, 2018R1C1B6009385, 2018M3A9F1023690, 2018M3A9F1023691"],"award-info":[{"award-number":["RF 2017R1D1A1A09000712, 2018R1C1B6009385, 2018M3A9F1023690, 2018M3A9F1023691"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>An electrochemical capacitance immunosensor based on an interdigitated wave-shaped micro electrode array (IDW\u00b5E) for direct and label-free detection of C-reactive protein (CRP) was reported. A self-assembled monolayer (SAM) of dithiobis (succinimidyl propionate) (DTSP) was used to modify the electrode array for antibody immobilization. The SAM functionalized electrode array was characterized morphologically by atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDX). The nature of gold-sulfur interactions on SAM-treated electrode array was probed by X-ray photoelectron spectroscopy (XPS). The covalent linking of anti-CRP-antibodies onto the SAM modified electrode array was characterized morphologically through AFM, and electrochemically through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The application of phosphate-buffered saline (PBS) and human serum (HS) samples containing different concentrations of CRP in the electrode array caused changes in the electrode interfacial capacitance upon CRP binding. CRP concentrations in PBS and HS were determined quantitatively by measuring the change in capacitance (\u0394C) through EIS. The electrode immobilized with anti-CRP-antibodies showed an increase in \u0394C with the addition of CRP concentrations over a range of 0.01\u201310,000 ng mL\u22121. The electrode showed detection limits of 0.025 ng mL\u22121 and 0.23 ng mL\u22121 (S\/N = 3) in PBS and HS, respectively. The biosensor showed a good reproducibility (relative standard deviation (RSD), 1.70%), repeatability (RSD, 1.95%), and adequate selectivity in presence of interferents towards CRP detection. The sensor also exhibited a significant storage stability of 2 weeks at 4 \u00b0C in 1\u00d7 PBS.<\/jats:p>","DOI":"10.3390\/s19245560","type":"journal-article","created":{"date-parts":[[2019,12,17]],"date-time":"2019-12-17T02:59:01Z","timestamp":1576551541000},"page":"5560","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Electrochemical Detection of C-Reactive Protein in Human Serum Based on Self-Assembled Monolayer-Modified Interdigitated Wave-Shaped Electrode"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8170-0652","authenticated-orcid":false,"given":"Somasekhar R.","family":"Chinnadayyala","sequence":"first","affiliation":[{"name":"Department of Electronic Engineering, Gachon University, Seongnam-si, Gyeonggi-do, Incheon 13120, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinsoo","family":"Park","sequence":"additional","affiliation":[{"name":"Gachon Advanced Institute for Health Science &amp; Technology, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Young Hyo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Otorhinolaryngology-Head and Neck Surgery, School of Medicine, Inha University, Incheon 22332, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seong Hye","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Neurology, School of Medicine, Inha University, Incheon 22332, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sang-Myung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Kangwon National University, Chuncheon 25341, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Won Woo","family":"Cho","sequence":"additional","affiliation":[{"name":"Cantis Inc., Ansan-si, Gyeonggi-do 15588, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ga-Yeon","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Yonsei University, Seoul 03772, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9954-6860","authenticated-orcid":false,"given":"Jae-Chul","family":"Pyun","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Yonsei University, Seoul 03772, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3839-6410","authenticated-orcid":false,"given":"Sungbo","family":"Cho","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Gachon University, Seongnam-si, Gyeonggi-do, Incheon 13120, Korea"},{"name":"Gachon Advanced Institute for Health Science &amp; Technology, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1186\/s13075-015-0563-z","article-title":"Role of C-reactive protein in osteoclastogenesis in rheumatoid arthritis","volume":"17","author":"Kim","year":"2015","journal-title":"Arthritis Res. Ther."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Shrotriya, S., Walsh, D., Bennani-Baiti, N., Thomas, S., and Lorton, C. (2015). C-Reactive Protein Is an Important Biomarker for Prognosis Tumor Recurrence and Treatment Response in Adult Solid Tumors: A Systematic Review. PLoS ONE, 10.","DOI":"10.1371\/journal.pone.0143080"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Thangamuthu, M., Santschi, C., and Martin, O.J.F. (2018). Label-Free Electrochemical Immunoassay for C-Reactive Protein. Biosensors, 8.","DOI":"10.3390\/bios8020034"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"6553","DOI":"10.1021\/ac300835b","article-title":"Sensitive Affimer and Antibody Based Impedimetric Label-Free Assays for C-Reactive Protein","volume":"84","author":"Johnson","year":"2012","journal-title":"Anal. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1805","DOI":"10.1172\/JCI200318921","article-title":"C-reactive protein: A critical update","volume":"111","author":"Pepys","year":"2003","journal-title":"J. Clin. Investig."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.snb.2014.10.012","article-title":"Development of a sensitive SPR biosensor for C-reactive protein (CRP) using plasma-treated Parylene-N film","volume":"207","author":"Choi","year":"2015","journal-title":"Sens. Actuators B Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"9653","DOI":"10.3390\/s130809653","article-title":"Electrical Detection of C-Reactive Protein Using a Single Free-Standing, Thermally Controlled Piezoresistive Microcantilever for Highly Reproducible and Accurate Measurements","volume":"13","author":"Yen","year":"2013","journal-title":"Sensors"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"943","DOI":"10.1021\/acs.langmuir.7b02724","article-title":"Critical Study of the Recognition between C-Reactive Protein and Surface-Immobilized Phosphorylcholine by Quartz Crystal Microbalance with Dissipation","volume":"34","author":"Wu","year":"2018","journal-title":"Langmuir"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/j.talanta.2018.02.075","article-title":"Electrochemical detection of C-reactive protein based on anthraquinone labeled antibody using a screen-printed graphene electrode","volume":"183","author":"Jampasa","year":"2018","journal-title":"Talanta"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1016\/j.biotechadv.2015.12.010","article-title":"Bioanalytical advances in assays for C-reactive protein","volume":"34","author":"Vashist","year":"2016","journal-title":"Biotechnol. Adv."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1515\/CCLM.2001.185","article-title":"High sensitivity immunoassays for C-reactive protein: Promises and pitfalls","volume":"39","author":"Ledue","year":"2001","journal-title":"Clin. Chem. Lab. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"340","DOI":"10.3390\/bios4040340","article-title":"Detection of the Inflammation Biomarker C-Reactive Protein in Serum Samples: Towards an Optimal Biosensor Formula","volume":"4","author":"Fakanya","year":"2014","journal-title":"Biosensors"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"5587","DOI":"10.1021\/ac501322x","article-title":"Localized surface Plasmon resonance nanosensing of C reactive protein with poly(2-methacryloyloxyethyl phosphorylcholine)-grafted gold nanoparticles prepared by surface-initiated atom transfer radical polymerization","volume":"86","author":"Kitayama","year":"2014","journal-title":"Anal. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1","DOI":"10.7567\/JJAP.55.06GN06","article-title":"Sensitivity enhancement of capacitive tumor necrosis factor-\u03b1 detection","volume":"55","author":"Yagati","year":"2016","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Yagati, A.K., Park, J., and Cho, S. (2016). Reduced Graphene Oxide Modified the Interdigitated Chain Electrode for an Insulin Sensor. Sensors, 16.","DOI":"10.3390\/s16010109"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1016\/j.bioelechem.2015.10.002","article-title":"Label-free and direct detection of C-reactive protein using reduced graphene oxide-nanoparticle hybrid impedimetric sensor","volume":"107","author":"Yagati","year":"2016","journal-title":"Bioelectrochemistry"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.bios.2014.01.044","article-title":"Comparing label free electrochemical impedimetric and capacitive biosensing architectures","volume":"57","author":"Fernandes","year":"2014","journal-title":"Biosens. Bioelectron."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"3302","DOI":"10.1039\/C8AN00430G","article-title":"A simple architecture with self-assembled monolayers to build immunosensors for detecting the pancreatic cancer biomarker CA19-9","volume":"143","author":"Soares","year":"2018","journal-title":"Analyst"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"17168","DOI":"10.1021\/ja306856y","article-title":"Anti-Fab Aptamers for Shielding Virus from Neutralizing Antibodies","volume":"134","author":"Muharemagic","year":"2012","journal-title":"J. Am. Chem. Soc."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1016\/j.bios.2005.12.025","article-title":"A comparative study of capacitive immunosensors based on self-assembled monolayers formed from thiourea, thioctic acid, and 3-mercaptopropionic acid","volume":"22","author":"Limbut","year":"2006","journal-title":"Biosens. Bioelectron."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"8133","DOI":"10.1039\/C5TB01672J","article-title":"Surface self-assembled hybrid nanocomposites with electroactive nanoparticles and enzymes confined in a polymer matrix for controlled electrocatalysis","volume":"3","author":"Zhu","year":"2015","journal-title":"J. Mater. Chem. B"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"15495","DOI":"10.1039\/C5NR03549J","article-title":"Peptide flatlandia: A new-concept peptide for positioning of electroactive probes in proximity to a metal surface","volume":"7","author":"Longo","year":"2015","journal-title":"Nanoscale"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"9700","DOI":"10.1038\/s41598-018-28035-3","article-title":"A sensitive electrochemical immunosensor for label-free detection of Zika-virus protein","volume":"8","author":"Kaushik","year":"2018","journal-title":"Sci. Rep."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2296","DOI":"10.1016\/j.bios.2010.03.016","article-title":"Dithiobis(succinimidyl propionate) modified gold microarray electrode based electrochemical immunosensor for ultrasensitive detection of cortisol","volume":"25","author":"Arya","year":"2010","journal-title":"Biosens. Bioelectron."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3077","DOI":"10.1149\/2.017402jes","article-title":"Electrochemical immunosensing of saliva cortisol","volume":"161","author":"Pasha","year":"2014","journal-title":"J. Electrochem. Soci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"104702","DOI":"10.1063\/1.4929350","article-title":"On sulfur core level binding energies in thiol self-assembly and alternative adsorption sites: An experimental and theoretical study","volume":"143","author":"Jia","year":"2015","journal-title":"J. Chem. Phys."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"4939","DOI":"10.1021\/la049868j","article-title":"Surface Structure and Chemical Switching of Thioctic Acid Adsorbed on Au (111) As Observed Using Near-Edge X-ray Absorption Fine Structure","volume":"20","author":"Willey","year":"2004","journal-title":"Langmuir"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"83164","DOI":"10.1039\/C5RA14139G","article-title":"XPS in development of chemical sensors","volume":"5","author":"Mazzotta","year":"2015","journal-title":"RSC. Adv."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"922","DOI":"10.1016\/j.ssi.2009.04.002","article-title":"On the physical interpretation of constant phase elements","volume":"180","author":"Berkemeier","year":"2009","journal-title":"Solid. State. Ion."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"307","DOI":"10.1016\/j.bios.2016.01.086","article-title":"Silver nanoflower-reduced graphene oxide composite based micro-disk electrode for insulin detection in serum","volume":"80","author":"Yagati","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1382","DOI":"10.1016\/j.bios.2006.06.012","article-title":"Self-assembled PEG monolayer based SPR immunosensor for label-free detection of insulin","volume":"22","author":"Gobi","year":"2007","journal-title":"Biosens. Bioelectron."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1007\/s00604-019-3245-8","article-title":"An origami paper-based electrochemical immunoassay for the C-reactive protein using a screen-printed carbon electrode modified with graphene and gold nanoparticles","volume":"186","author":"Boonkaew","year":"2019","journal-title":"Microchim. Acta"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"463","DOI":"10.1007\/s00604-016-2022-1","article-title":"A triple immunochromatographic test for simultaneous determination of cardiac troponin I, fatty acid binding protein and C-reactive protein biomarkers","volume":"184","author":"Byzova","year":"2017","journal-title":"Microchim. Acta"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1016\/j.bios.2014.11.017","article-title":"Graphene-based rapid and highly-sensitive immunoassay for C-reactive protein using a smartphone-based colorimetric reader","volume":"66","author":"Vashist","year":"2015","journal-title":"Biosens. Bioelectron."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"61906","DOI":"10.1039\/C5RA12527H","article-title":"Magnetic chemiluminescent immunoassay for human C-reactive protein on the centrifugal microfluidics platform","volume":"5","author":"Czilwik","year":"2015","journal-title":"RSC Adv."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2133","DOI":"10.1021\/ac7021376","article-title":"Electrochemical impedance immunosensor based on three-dimensionally ordered macroporous gold film","volume":"80","author":"Chen","year":"2008","journal-title":"Anal. Chem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1016\/j.snb.2012.10.099","article-title":"Enhancement of the sensitivity of LSPR-based CRP immunosensors by Au nanoparticle antibody conjugation","volume":"177","author":"Yeom","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1039\/b414194f","article-title":"Application of microchip assay system for the measurement of C-reactive protein in human saliva","volume":"5","author":"Christodoulides","year":"2005","journal-title":"Lab Chip"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"494","DOI":"10.1016\/j.snb.2013.01.013","article-title":"Ultratrace detection of C-reactive protein by a piezoelectric immunosensor based on Fe3O4@SiO2 magnetic capture nanoprobes and HRP-antibody co-immobilized nano gold as signal tags","volume":"178","author":"Zhou","year":"2013","journal-title":"Sens. Actuators B Chem."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/24\/5560\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:42:50Z","timestamp":1760190170000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/19\/24\/5560"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,12,16]]},"references-count":39,"journal-issue":{"issue":"24","published-online":{"date-parts":[[2019,12]]}},"alternative-id":["s19245560"],"URL":"https:\/\/doi.org\/10.3390\/s19245560","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,12,16]]}}}