{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T03:23:07Z","timestamp":1772508187636,"version":"3.50.1"},"reference-count":34,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2015,5,21]],"date-time":"2015-05-21T00:00:00Z","timestamp":1432166400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Recently ZnO has attracted much interest because of its usefulness for intracellular measurements of biochemical species by using its semiconducting, electrochemical, catalytic properties and for being biosafe and biocompatible. ZnO thus has a wide range of applications in optoelectronics, intracellular nanosensors, transducers, energy conversion and medical sciences. This review relates specifically to intracellular electrochemical (glucose and free metal ion) biosensors based on functionalized zinc oxide nanowires\/nanorods.  For intracellular measurements, the ZnO nanowires\/nanorods were grown on the tip of a borosilicate glass capillary (0.7 \u00b5m in diameter) and functionalized with membranes or enzymes to produce intracellular selective metal ion or glucose sensors. Successful intracellular measurements were carried out using ZnO nanowires\/nanorods grown on small tips for glucose and free metal ions using two types of cells, human fat cells and frog oocytes. The sensors in this study were used to detect real-time changes of metal ions and glucose across human fat cells and frog cells using changes in the electrochemical potential at the interface of the intracellular micro-environment. Such devices are helpful in explaining various intracellular processes involving ions and glucose.<\/jats:p>","DOI":"10.3390\/s150511787","type":"journal-article","created":{"date-parts":[[2015,5,21]],"date-time":"2015-05-21T10:30:59Z","timestamp":1432204259000},"page":"11787-11804","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["ZnO Nanostructure-Based Intracellular Sensor"],"prefix":"10.3390","volume":"15","author":[{"given":"Muhammad","family":"Asif","sequence":"first","affiliation":[{"name":"Department of Physics, COMSATS Institute of Information Technology, Lahore 54000, Pakistan"},{"name":"Acromed Invest AB, Magistratsv\u00e4gen 10, Lund SE-22643, Sweden"}]},{"given":"Bengt","family":"Danielsson","sequence":"additional","affiliation":[{"name":"Acromed Invest AB, Magistratsv\u00e4gen 10, Lund SE-22643, Sweden"}]},{"given":"Magnus","family":"Willander","sequence":"additional","affiliation":[{"name":"Department of Science and Technology, Campus Norrk\u00f6ping, Link\u00f6ping University,  Norrk\u00f6ping SE-60174, Sweden"}]}],"member":"1968","published-online":{"date-parts":[[2015,5,21]]},"reference":[{"key":"ref_1","unstructured":"Le, L.-A., Hunter, R.J., and Victor, R. 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