{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T17:13:35Z","timestamp":1790702015039,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,17]],"date-time":"2021-01-17T00:00:00Z","timestamp":1610841600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/BIA-MOL\/31069\/2017 and the ERDF through COMPETE2020 (POCI-01-0145- FEDER-031069)"],"award-info":[{"award-number":["PTDC\/BIA-MOL\/31069\/2017 and the ERDF through COMPETE2020 (POCI-01-0145- FEDER-031069)"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biosensors"],"abstract":"<jats:p>Liquid-gated Graphene Field-Effect Transistors (GFET) are ultrasensitive bio-detection platforms carrying out the graphene\u2019s exceptional intrinsic functionalities. Buffer and dilution factor are prevalent strategies towards the optimum performance of the GFETs. However, beyond the Debye length (\u03bbD), the role of the graphene-electrolytes\u2019 ionic species interactions on the DNA behavior at the nanoscale interface is complicated. We studied the characteristics of the GFETs under different ionic strength, pH, and electrolyte type, e.g., phosphate buffer (PB), and phosphate buffer saline (PBS), in an automatic portable built-in system. The electrostatic gating and charge transfer phenomena were inferred from the field-effect measurements of the Dirac point position in single-layer graphene (SLG) transistors transfer curves. Results denote that \u03bbD is not the main factor governing the effective nanoscale screening environment. We observed that the longer \u03bbD was not the determining characteristic for sensitivity increment and limit of detection (LoD) as demonstrated by different types and ionic strengths of measuring buffers. In the DNA hybridization study, our findings show the role of the additional salts present in PBS, as compared to PB, in increasing graphene electron mobility, electrostatic shielding, intermolecular forces and DNA adsorption kinetics leading to an improved sensitivity.<\/jats:p>","DOI":"10.3390\/bios11010024","type":"journal-article","created":{"date-parts":[[2021,1,18]],"date-time":"2021-01-18T05:17:34Z","timestamp":1610947054000},"page":"24","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":37,"title":["Influence of the Electrolyte Salt Concentration on DNA Detection with Graphene Transistors"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4457-2778","authenticated-orcid":false,"given":"Agnes","family":"Purwidyantri","sequence":"first","affiliation":[{"name":"Food Quality and Safety Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Telma","family":"Domingues","sequence":"additional","affiliation":[{"name":"2D Materials and Devices Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5622-7760","authenticated-orcid":false,"given":"J\u00e9r\u00f4me","family":"Borme","sequence":"additional","affiliation":[{"name":"2D Materials and Devices Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joana Rafaela","family":"Guerreiro","sequence":"additional","affiliation":[{"name":"Food Quality and Safety Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrey","family":"Ipatov","sequence":"additional","affiliation":[{"name":"Food Quality and Safety Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9116-2395","authenticated-orcid":false,"given":"Catarina M.","family":"Abreu","sequence":"additional","affiliation":[{"name":"Nanomedicine Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1531-1675","authenticated-orcid":false,"given":"Marco","family":"Martins","sequence":"additional","affiliation":[{"name":"Nano-ICs Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9875-6188","authenticated-orcid":false,"given":"Pedro","family":"Alpuim","sequence":"additional","affiliation":[{"name":"2D Materials and Devices Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"},{"name":"Center of Physics, University of Minho, 4710-057 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0529-5771","authenticated-orcid":false,"given":"Marta","family":"Prado","sequence":"additional","affiliation":[{"name":"Food Quality and Safety Group, International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jos\u00e9 Veiga, 4715-330 Braga, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1103\/RevModPhys.81.109","article-title":"The electronic properties of grapheme","volume":"81","author":"Neto","year":"2009","journal-title":"Rev. Mod. Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/j.mattod.2013.09.004","article-title":"Graphene based materials for biomedical applications","volume":"16","author":"Yang","year":"2013","journal-title":"Mater. Today"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Forsyth, R., Devadoss, A., and Guy, O.J. (2017). Graphene Field Effect Transistors for Biomedical Applications: Current Status and Future Prospects. 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