{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T04:49:27Z","timestamp":1788324567018,"version":"build-2803163510"},"reference-count":62,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2025,7,10]],"date-time":"2025-07-10T00:00:00Z","timestamp":1752105600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Faculty Sponsored Student Research Awards (FSSRAs)"},{"name":"Department of Chemistry and Biochemistry (CBC)"},{"name":"College of Science and Mathematics at California State University (CSU), Fresno"},{"name":"Doris A. Howell Foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Glutamate, the primary excitatory neurotransmitter in the central nervous system, plays a pivotal role in synaptic signaling, learning, and memory. Abnormal glutamate levels are implicated in various neurological disorders, including epilepsy, Alzheimer\u2019s disease, and ischemic stroke. Despite the utility of magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) in diagnosing such conditions, the development of effective glutamate-sensitive contrast agents remains a challenge. In this study, we present ultrasmall, citric acid-coated superparamagnetic iron oxide nanoparticles (CA-SPIONs) as highly selective and sensitive MRS probes for glutamate detection. These 5 nm magnetite CA-SPIONs exhibit a stable dispersion in physiological buffers and undergo aggregation in the presence of glutamate, significantly enhancing the T2 MRS contrast power. At physiological glutamate levels, the CA-SPIONs yielded a pronounced signal change ratio of nearly 60%, while showing a negligible response to other neurotransmitters such as GABA and dopamine. Computational simulations confirmed the mechanism of glutamate-mediated aggregation and its impact on transversal relaxation rates and relaxivities. The sensitivity and selectivity of CA-SPIONs underscore their potential as eco-friendly, iron-based alternatives for future neurological sensing applications targeting glutamatergic dysfunction.<\/jats:p>","DOI":"10.3390\/s25144326","type":"journal-article","created":{"date-parts":[[2025,7,11]],"date-time":"2025-07-11T10:26:53Z","timestamp":1752229613000},"page":"4326","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Ultrasmall Superparamagnetic Magnetite Nanoparticles as Glutamate-Responsive Magnetic Resonance Sensors"],"prefix":"10.3390","volume":"25","author":[{"given":"Hannah","family":"Mettee","sequence":"first","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aaron","family":"Asparin","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zulaikha","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5713-8233","authenticated-orcid":false,"given":"Shi","family":"He","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, California State University Fresno, 2320 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianzhi","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6297-9427","authenticated-orcid":false,"given":"Joshua","family":"Hall","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexis","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6146-3613","authenticated-orcid":false,"given":"Shuo","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, California State University Fresno, 2320 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1607-9564","authenticated-orcid":false,"given":"Morgan J.","family":"Hawker","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masaki","family":"Uchida","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7188-8105","authenticated-orcid":false,"given":"He","family":"Wei","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, California State University Fresno, 2555 E San Ramon Ave, Fresno, CA 93740, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,10]]},"reference":[{"key":"ref_1","unstructured":"(2025, February 06). Glutamate: What It Is & Function, Available online: https:\/\/my.clevelandclinic.org\/health\/articles\/22839-glutamate."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Pal, M.M. (2021). Glutamate: The Master Neurotransmitter and Its Implications in Chronic Stress and Mood Disorders. Front. Hum. Neurosci., 15.","DOI":"10.3389\/fnhum.2021.722323"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Bukke, V.N., Archana, M., Villani, R., Romano, A.D., Wawrzyniak, A., Balawender, K., Orkisz, S., Beggiato, S., Serviddio, G., and Cassano, T. (2020). The Dual Role of Glutamatergic Neurotransmission in Alzheimer\u2019s Disease: From Pathophysiology to Pharmacotherapy. Int. J. Mol. Sci., 21.","DOI":"10.3390\/ijms21207452"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Li, C.-T., Yang, K.-C., and Lin, W.-C. (2019). Glutamatergic Dysfunction and Glutamatergic Compounds for Major Psychiatric Disorders: Evidence from Clinical Neuroimaging Studies. Front. Psychiatry, 9.","DOI":"10.3389\/fpsyt.2018.00767"},{"key":"ref_5","unstructured":"Institute of Medicine (US) Forum on Neuroscience and Nervous System (2011). Overview of the Glutamatergic System. Glutamate-Related Biomarkers in Drug Development for Disorders of the Nervous System: Workshop Summary, National Academies Press (US)."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2554","DOI":"10.1007\/s11064-012-0848-4","article-title":"Metabolic Pathways and Activity-Dependent Modulation of Glutamate Concentration in the Human Brain","volume":"37","author":"Mangia","year":"2012","journal-title":"Neurochem. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"799","DOI":"10.1007\/s00702-014-1180-8","article-title":"Glutamate as a Neurotransmitter in the Healthy Brain","volume":"121","author":"Zhou","year":"2014","journal-title":"J. Neural Transm."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"105977","DOI":"10.1016\/j.tiv.2024.105977","article-title":"Sinapic Acid Alleviates Glutamate-Induced Excitotoxicity by Inhibiting Neuroinflammation and Endoplasmic Reticulum Stress Pathway in C6 Glioma Cells","volume":"103","author":"Ortasoz","year":"2025","journal-title":"Toxicol. Vitro Int. J. Publ. Assoc. BIBRA"},{"key":"ref_9","unstructured":"(2025, February 05). Magnetic Resonance Imaging (MRI). National Institute of Biomedical Imaging and Bioengineering, Available online: https:\/\/www.nibib.nih.gov\/science-education\/science-topics\/magnetic-resonance-imaging-mri."},{"key":"ref_10","unstructured":"Kapoor, M., Heston, T.F., and Kasi, A. (2025). PET Scanning. StatPearls, StatPearls Publishing."},{"key":"ref_11","unstructured":"Al-Naser, Y.A., and Tafti, D. (2024). MRI Patient Safety and Care. StatPearls, StatPearls Publishing."},{"key":"ref_12","unstructured":"(2025, February 06). MRI Basics. Available online: https:\/\/case.edu\/med\/neurology\/NR\/MRI%20Basics.htm."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"772","DOI":"10.1148\/radiol.15150025","article-title":"Intracranial Gadolinium Deposition after Contrast-Enhanced MR Imaging","volume":"275","author":"McDonald","year":"2015","journal-title":"Radiology"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"630","DOI":"10.1148\/radiol.2015150805","article-title":"Residual or Retained Gadolinium: Practical Implications for Radiologists and Our Patients","volume":"275","author":"Kanal","year":"2015","journal-title":"Radiology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1007\/s10534-016-9931-7","article-title":"Gadolinium-Based Contrast Agent Toxicity: A Review of Known and Proposed Mechanisms","volume":"29","author":"Rogosnitzky","year":"2016","journal-title":"BioMetals"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"6801","DOI":"10.1021\/acsnano.9b01511","article-title":"Toxicological Risk Assessments of Iron Oxide Nanocluster- and Gadolinium-Based T1MRI Contrast Agents in Renal Failure Rats","volume":"13","author":"Weng","year":"2019","journal-title":"ACS Nano"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"302","DOI":"10.1053\/j.ackd.2010.05.002","article-title":"The Aging Kidney: Physiological Changes","volume":"17","author":"Weinstein","year":"2010","journal-title":"Adv. Chronic Kidney Dis."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"168520","DOI":"10.1016\/j.jmmm.2021.168520","article-title":"SPIO Nanoparticles and Magnetic Erythrocytes as Contrast Agents for Biomedical and Diagnostic Applications","volume":"541","author":"Antonelli","year":"2022","journal-title":"J. Magn. Magn. Mater."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Ferreira-Filho, V.C., Morais, B., Vieira, B.J.C., Waerenborgh, J.C., Carmezim, M.J., T\u00f3th, C.N., M\u00eame, S., Lacerda, S., Jaque, D., and Sousa, C.T. (2024). Influence of SPION Surface Coating on Magnetic Properties and Theranostic Profile. Molecules, 29.","DOI":"10.20944\/preprints202403.1694.v1"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"W302","DOI":"10.2214\/AJR.14.12733","article-title":"Iron-Based Superparamagnetic Nanoparticle Contrast Agents for MRI of Infection and Inflammation","volume":"204","author":"Neuwelt","year":"2015","journal-title":"AJR Am. J. Roentgenol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"424","DOI":"10.7150\/ntno.86467","article-title":"Magnetic Resonance Imaging and Iron-Oxide Nanoparticles in the Era of Personalized Medicine","volume":"7","author":"Rahman","year":"2023","journal-title":"Nanotheranostics"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2777","DOI":"10.1007\/s10948-011-1264-8","article-title":"Effect of Synthesis Parameters on the Properties of Superparamagnetic Iron Oxide Nanoparticles","volume":"25","author":"Karaagac","year":"2012","journal-title":"J. Supercond. Nov. Magn."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"168","DOI":"10.1007\/s41365-024-01527-w","article-title":"Structural Control of Magnetic Nanoparticles for Positive Nuclear Magnetic Resonance Imaging","volume":"35","author":"Ali","year":"2024","journal-title":"Nucl. Sci. Tech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"2325","DOI":"10.1073\/pnas.1620145114","article-title":"Exceedingly Small Iron Oxide Nanoparticles as Positive MRI Contrast Agents","volume":"114","author":"Wei","year":"2017","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e2102340118","DOI":"10.1073\/pnas.2102340118","article-title":"Single-Nanometer Iron Oxide Nanoparticles as Tissue-Permeable MRI Contrast Agents","volume":"118","author":"Wei","year":"2021","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e2220036120","DOI":"10.1073\/pnas.2220036120","article-title":"Fast Detection of Liver Fibrosis with Collagen-Binding Single-Nanometer Iron Oxide Nanoparticles via T1-Weighted MRI","volume":"120","author":"Zhang","year":"2023","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Girardet, T., Venturini, P., Martinez, H., Dupin, J.-C., Cleymand, F., and Fleutot, S. (2022). Spinel Magnetic Iron Oxide Nanoparticles: Properties, Synthesis and Washing Methods. Appl. Sci., 12.","DOI":"10.3390\/app12168127"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"329","DOI":"10.1016\/j.mee.2013.02.045","article-title":"Effect of Synthesis Conditions on the Properties of Citric-Acid Coated Iron Oxide Nanoparticles","volume":"110","author":"Li","year":"2013","journal-title":"Microelectron. Eng."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1507","DOI":"10.1002\/cphc.201700126","article-title":"C 1s Peak of Adventitious Carbon Aligns to the Vacuum Level: Dire Consequences for Material\u2019s Bonding Assignment by Photoelectron Spectroscopy","volume":"18","author":"Greczynski","year":"2017","journal-title":"ChemPhysChem"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"829","DOI":"10.1039\/D3YA00082F","article-title":"Copper and Iron Co-Doping Effects on the Structure, Optical Energy Band Gap, and Catalytic Behaviour of Co3O4 Nanocrystals towards Low-Temperature Total Oxidation of Toluene","volume":"2","author":"Assaouka","year":"2023","journal-title":"Energy Adv."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"4709","DOI":"10.1103\/PhysRevB.5.4709","article-title":"High-Resolution X-Ray Photoemission Spectrum of the Valence Bands of Gold","volume":"5","author":"Shirley","year":"1972","journal-title":"Phys. Rev. B"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"2764","DOI":"10.1038\/npp.2012.142","article-title":"The Impact of Gabapentin Administration on Brain GABA and Glutamate Concentrations: A 7T 1H-MRS Study","volume":"37","author":"Cai","year":"2012","journal-title":"Neuropsychopharmacology"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"6084","DOI":"10.1523\/JNEUROSCI.14-10-06084.1994","article-title":"Efflux of Dopamine from the Synaptic Cleft in the Nucleus Accumbens of the Rat Brain","volume":"14","author":"Garris","year":"1994","journal-title":"J. Neurosci. Off. J. Soc. Neurosci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1111\/j.1471-4159.2012.07677.x","article-title":"Sources Contributing to the Average Extracellular Concentration of Dopamine in the Nucleus Accumbens","volume":"121","author":"Roitman","year":"2012","journal-title":"J. Neurochem."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"957","DOI":"10.1021\/acs.chemrev.8b00363","article-title":"Chemistry of MRI Contrast Agents: Current Challenges and New Frontiers","volume":"119","author":"Wahsner","year":"2019","journal-title":"Chem. Rev."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Rukshin, I., Mohrenweiser, J., Yue, P., and Afkhami, S. (2017). Modeling Superparamagnetic Particles in Blood Flow for Applications in Magnetic Drug Targeting. Fluids, 2.","DOI":"10.3390\/fluids2020029"},{"key":"ref_37","first-page":"35","article-title":"Superparamagnetic Iron Oxide Based MRI Contrast Agents: Current Status of Clinical Application","volume":"1","author":"Wang","year":"2011","journal-title":"Quant. Imaging Med. Surg."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"994","DOI":"10.1016\/j.mri.2008.01.039","article-title":"T2 Relaxation Induced by Clusters of Superparamagnetic Nanoparticles: Monte Carlo Simulations","volume":"26","author":"Matsumoto","year":"2008","journal-title":"Magn. Reson. Imaging"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"83","DOI":"10.1007\/s40336-022-00528-2","article-title":"Ultrasmall Iron Oxide Nanoparticles and Gadolinium-Based Contrast Agents in Magnetic Resonance Imaging: A Systematic Review and Meta-Analysis","volume":"11","author":"Amraee","year":"2023","journal-title":"Clin. Transl. Imaging"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Bertolucci, E., Galletti, A.M.R., Antonetti, C., Marracci, M., Tellini, B., Piccinelli, F., and Visone, C. (2015, January 11\u201314). Chemical and Magnetic Properties Characterization of Magnetic Nanoparticles. Proceedings of the 2015 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, Pisa, Italy.","DOI":"10.1109\/I2MTC.2015.7151498"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"020022","DOI":"10.1088\/2632-959X\/ac0596","article-title":"PEG Size Effect and Its Interaction with Fe3O4 Nanoparticles Synthesized by Solvothermal Method: Morphology and Effect of pH on the Stability","volume":"2","author":"Namikuchi","year":"2021","journal-title":"Nano Express"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Zhuang, L., Zhang, W., Zhao, Y., Shen, H., Lin, H., and Liang, J. (2015). Preparation and Characterization of Fe3O4 Particles with Novel Nanosheets Morphology and Magnetochromatic Property by a Modified Solvothermal Method. Sci. Rep., 5.","DOI":"10.1038\/srep09320"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"503","DOI":"10.1007\/s00604-019-3623-2","article-title":"Magnetic Nanocomposite-Based SELDI Probe for Extraction and Detection of Drugs, Amino Acids and Fatty Acids","volume":"186","author":"Amin","year":"2019","journal-title":"Microchim. Acta"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"104729","DOI":"10.1016\/j.jwpe.2023.104729","article-title":"Ultra-Efficient and Selective Adsorption of Cationic Dyes by Ti-Doped SiO2 Functionalized Hydrophilic Fe3O4 Nanoparticles with Superior Structural Stability","volume":"57","author":"Cai","year":"2024","journal-title":"J. Water Process Eng."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"3837","DOI":"10.1016\/j.biomaterials.2013.01.087","article-title":"Monodisperse Magnetite Nanoparticle Tracers for in Vivo Magnetic Particle Imaging","volume":"34","author":"Khandhar","year":"2013","journal-title":"Biomaterials"},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Rajan, A., Sharma, M., and Sahu, N.K. (2020). Assessing Magnetic and Inductive Thermal Properties of Various Surfactants Functionalised Fe3O4 Nanoparticles for Hyperthermia. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-71703-6"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Tsioptsias, C., Panagiotou, A., and Mitlianga, P. (2024). Thermal Behavior and Infrared Absorbance Bands of Citric Acid. Appl. Sci., 14.","DOI":"10.3390\/app14188406"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"012022","DOI":"10.1088\/1742-6596\/1829\/1\/012022","article-title":"Optical and Morphology Properties of the Magnetite (Fe3O4) Nanoparticles Prepared by Green Method","volume":"1829","author":"Abdallah","year":"2021","journal-title":"J. Phys. Conf. Ser."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"135322","DOI":"10.1016\/j.snb.2024.135322","article-title":"A Low-Fouling Electrochemical Biosensor Based on Multifunction Branched Peptides with Antifouling, Antibacterial and Recognizing Sequences for Protein Detection in Saliva","volume":"405","author":"Li","year":"2024","journal-title":"Sens. Actuators B Chem."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Dheyab, M.A., Aziz, A.A., Jameel, M.S., Noqta, O.A., Khaniabadi, P.M., and Mehrdel, B. (2020). Simple Rapid Stabilization Method through Citric Acid Modification for Magnetite Nanoparticles. Sci. Rep., 10.","DOI":"10.1038\/s41598-020-67869-8"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.jallcom.2012.05.053","article-title":"Properties of Surface Functionalized Iron Oxide Nanoparticles (Ferrofluid) Conjugated Antibody for Lateral Flow Immunoassay Application","volume":"538","author":"Tan","year":"2012","journal-title":"J. Alloys Compd."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Mikelashvili, V., Kekutia, S., Markhulia, J., Saneblidze, L., Maisuradze, N., Kriechbaum, M., and Alm\u00e1sy, L. (2023). Synthesis and Characterization of Citric Acid-Modified Iron Oxide Nanoparticles Prepared with Electrohydraulic Discharge Treatment. Materials, 16.","DOI":"10.3390\/ma16020746"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"3343","DOI":"10.1021\/acsami.6b12932","article-title":"Individually Stabilized, Superparamagnetic Nanoparticles with Controlled Shell and Size Leading to Exceptional Stealth Properties and High Relaxivities","volume":"9","author":"Lassenberger","year":"2017","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Dadfar, S.M., Camozzi, D., Darguzyte, M., Roemhild, K., Varvar\u00e0, P., Metselaar, J., Banala, S., Straub, M., G\u00fcvener, N., and Engelmann, U. (2020). Size-Isolation of Superparamagnetic Iron Oxide Nanoparticles Improves MRI, MPI and Hyperthermia Performance. J. Nanobiotechnol., 18.","DOI":"10.1186\/s12951-020-0580-1"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"2234","DOI":"10.1039\/D3NA01064C","article-title":"Advancing MRI with Magnetic Nanoparticles: A Comprehensive Review of Translational Research and Clinical Trials","volume":"6","author":"Lapusan","year":"2024","journal-title":"Nanoscale Adv."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"101931","DOI":"10.1016\/j.nantod.2023.101931","article-title":"Stimuli-Responsive Switchable MRI Nanoprobe for Tumor Theranostics","volume":"51","author":"Chen","year":"2023","journal-title":"Nano Today"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"7264","DOI":"10.1039\/D0TB01033B","article-title":"pH-Responsive Nanocomposite Fibres Allowing MRI Monitoring of Drug Release","volume":"8","author":"Zhang","year":"2020","journal-title":"J. Mater. Chem. B"},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1609","DOI":"10.1007\/s00216-021-03783-w","article-title":"Highly Selective and Sensitive Detection of Glutamate by an Electrochemical Aptasensor","volume":"414","author":"Wu","year":"2022","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1039\/D4FD00138A","article-title":"Enzyme-Modified Pt Nanoelectrodes for Glutamate Detection","volume":"257","author":"Xu","year":"2025","journal-title":"Faraday Discuss."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"103557","DOI":"10.1016\/j.cis.2025.103557","article-title":"Polymer Nanocomposite-Based Biomolecular Sensor for Healthcare Monitoring","volume":"343","author":"Natarajan","year":"2025","journal-title":"Adv. Colloid Interface Sci."},{"key":"ref_61","doi-asserted-by":"crossref","unstructured":"Cember, A.T.J., Nanga, R.P.R., and Reddy, R. (2023). Glutamate-Weighted CEST (gluCEST) Imaging for Mapping Neurometabolism: An Update on the State of the Art and Emerging Findings from in Vivo Applications. NMR Biomed., 36.","DOI":"10.1002\/nbm.4780"},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Geraldes, C.F.G.C. (2024). Rational Design of Magnetic Nanoparticles as T1\u2013T2 Dual-Mode MRI Contrast Agents. Molecules, 29.","DOI":"10.3390\/molecules29061352"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/14\/4326\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:08:08Z","timestamp":1760033288000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/25\/14\/4326"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,7,10]]},"references-count":62,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2025,7]]}},"alternative-id":["s25144326"],"URL":"https:\/\/doi.org\/10.3390\/s25144326","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,7,10]]}}}