Materials Chemistry and Physics 244 (2020) 122740 Available online 30 January 2020 0254-0584/© 2020 Elsevier B.V. All rights reserved. Fabrication of dopamine sensor based on ternary AlMn 0.645 Cr 1.76 O 7.47 nanoparticles M.M. Alam a , Abdullah M. Asiri b, c , Mohammed M. Rahman b, c, * , M.A. Islam a, ** a Department of Chemical Engineering and Polymer Science, Shahjalal University of Science and Technology, Sylhet, 3100, Bangladesh b Chemistry Department, King Abdulaziz University, Faculty of Science, Jeddah, 21589, P.O. Box 80203, Saudi Arabia c Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, Jeddah, 21589, P.O. Box 80203, Saudi Arabia HIGHLIGHTS G R A P H I C A L ABSTRACT � AlMn 0.645 Cr 1.76 O 7.47 NPs were synthe- sized by wet-chemical method. � NPs were deposited on GCE by using 5% nafon chemical binder. � Sensor was exhibited the highest sensi- tivity and lowest detection limit. � Validated with real bio-samples samples. � Biomedical and health safety. A R T I C L E INFO Keywords: AlMn 0.645 Cr 1.76 O 7.47 nanoparticles Wet-chemical method Electrochemical method Dopamine sensor Glassy carbon electrode Healthcare safety ABSTRACT A reliable and highly sensitive dopamine sensor was fabricated with mixture of Al–Mn–Cr-oxide (the composition is found as AlMn 0.65 Cr 1.76 O 7.47 ) nanoparticles (NPs). The wet-chemically synthesized NPs was deposited onto a glassy carbon electrode (GCE) as a layer of thin flm using conductive 5% Nafon suspension in ethanol as a chemical binder. The assembled AlMn 0.65 Cr 1.76 O 7.47 NPs/binder/GCE sensor was selective towards dopamine and was implemented to analyze a number of dopamine solutions with various concentration. The electro- chemical response of the sensor was found to be indifferent to the presence of electrolytes like Na þ , K þ , Ca 2þ and Fe 2þ in the analyte-samples. The electrochemical response of the sensor was reproducible in replicate runs at a single time of use as well as in usage at different time-intervals. The I vs. logC plot was linear over a range of as wide as 0.1 nM- 0.01 mM. The sensitivity of the assembled electrode at the applied potential þ1.5 V was found to be 55.8165 μAμM 1 cm 2 , while the detection limit was 96.87 � 4.84 pM. The fabricated sensor was detected the dopamine effectively and measured it in the real biological samples precisely. Thus, the present approach to developing sensors has acquired immense potential signifcance for future application in biomedical sector. 1. Introduction Generally, dopamine (3,4-dihydroxyphenylethylamine) is an biochemical that belongs to catecholamine and phenethylamine fam- ilies. It performs several important roles in different organs of mammals. Dopamine is a chemical found naturally in the human body. It is a * Corresponding author. Chemistry Department, King Abdulaziz University, Faculty of Science, Jeddah, 21589, P.O. Box 80203, Saudi Arabia. ** Corresponding author. E-mail addresses: mmrahman@kau.edu.sa (M.M. Rahman), islamsust@yahoo.com (M.A. Islam). Contents lists available at ScienceDirect Materials Chemistry and Physics journal homepage: www.elsevier.com/locate/matchemphys https://doi.org/10.1016/j.matchemphys.2020.122740 Received 7 December 2019; Received in revised form 21 January 2020; Accepted 28 January 2020