{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:55:08Z","timestamp":1760237708472,"version":"build-2065373602"},"reference-count":46,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,17]],"date-time":"2020-06-17T00:00:00Z","timestamp":1592352000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61775082; U1701268; 61675091; 61705083; 61805106"],"award-info":[{"award-number":["61775082; U1701268; 61675091; 61705083; 61805106"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program","award":["2019BT02X105"],"award-info":[{"award-number":["2019BT02X105"]}]},{"DOI":"10.13039\/501100003453","name":"Guangdong Natural Science Foundation","doi-asserted-by":"publisher","award":["2018A030313677"],"award-info":[{"award-number":["2018A030313677"]}],"id":[{"id":"10.13039\/501100003453","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fiber optical refractometers have gained a substantial reputation in biological and chemical sensing domain regarding their label-free and remote-operation working mode. However, the practical breakthrough of the fiber optical bio\/chemosensor is impeded by a lack of reconfigurability as well as the explicitness of the determination between bulk and surface refractive indices. In this letter, we further implement the highly flexible and reproducible long period grating called \u201cVIOLIN\u201d in chemical sensing area for the demonstration of moving those obstacles. In this configuration, the liquid is not only leveraged as the chemical carrier but also the periodic modulation of the optical fiber to facilitate the resonant signal. The thiol compound that is adsorbed by the fluidic substrate can be transduced to the pure alteration of the bulk refractive index of the liquid, which can be sensitively perceived by the resonant drift. Taking advantage of its freely dismantled feature, the VIOLIN sensor enables flexible reproduction and high throughput detection, yielding a new vision to the fiber optic biochemical sensing field.<\/jats:p>","DOI":"10.3390\/s20123415","type":"journal-article","created":{"date-parts":[[2020,6,17]],"date-time":"2020-06-17T13:11:32Z","timestamp":1592399492000},"page":"3415","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Label-Free and Reproducible Chemical Sensor Using the Vertical-Fluid-Array Induced Optical Fiber Long Period Grating (VIOLIN)"],"prefix":"10.3390","volume":"20","author":[{"given":"Deming","family":"Hu","sequence":"first","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Zhiyuan","family":"Xu","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Junqiu","family":"Long","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Peng","family":"Xiao","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Lili","family":"Liang","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Lipeng","family":"Sun","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Hao","family":"Liang","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9170-7620","authenticated-orcid":false,"given":"Yang","family":"Ran","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]},{"given":"Bai-Ou","family":"Guan","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chiavaioli, F., Gouveia, A.J.C., Jorge, A.S.P., and Baldini, F. (2017). Towards a Uniform Metrological Assessment of Grating-Based Optical Fiber Sensors: From Refractometers to Biosensors. Biosensors, 7.","DOI":"10.3390\/bios7020023"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2616","DOI":"10.1109\/JLT.2018.2889324","article-title":"Interface Sensitized Optical Microfiber Biosensors","volume":"37","author":"Guan","year":"2019","journal-title":"J. Lightwave Technol."},{"key":"ref_3","first-page":"100015","article-title":"Trends in the design of wavelength-based optical fibre biosensors (2008\u20132018)","volume":"1","author":"Santano","year":"2019","journal-title":"Biosens. Bioelectron. X"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1021\/acs.analchem.9b04708","article-title":"Fiber-Optic Chemical Sensors and Biosensors (2015\u20132019)","volume":"92","author":"Wang","year":"2020","journal-title":"Anal. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"452","DOI":"10.1016\/j.bios.2013.12.054","article-title":"In-situ detection of density alteration in non-physiological cells with polarimetric tilted fiber grating sensors","volume":"55","author":"Guo","year":"2014","journal-title":"Biosens. Bioelectron."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1016\/j.snb.2017.06.139","article-title":"Design, fabrication and characterisation of silica-titania thin film coated over coupled long period fibre gratings: Towards bio-sensing applications","volume":"253","author":"Biswas","year":"2017","journal-title":"Sens. Actuators B Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.bios.2017.08.061","article-title":"A label-free cardiac biomarker immunosensor based on phase-shifted microfiber Bragg grating","volume":"100","author":"Liu","year":"2018","journal-title":"Biosens. Bioelectron."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1364\/OL.33.000303","article-title":"Mach-Zehnder interferometers assembled with optical microfibers or nanofibers","volume":"33","author":"Li","year":"2008","journal-title":"Opt. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3593","DOI":"10.1364\/OL.36.003593","article-title":"Ultrasensitive refractive-index sensors based on rectangular silica microfibers","volume":"36","author":"Li","year":"2011","journal-title":"Opt. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"26714","DOI":"10.1364\/OE.21.026714","article-title":"Bending effect on modal interference in a fiber taper and sensitivity enhancement for refractive index measurement","volume":"21","author":"Sun","year":"2013","journal-title":"Opt. Express"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"161108","DOI":"10.1063\/1.1906317","article-title":"Optical microfiber loop resonator","volume":"86","author":"Sumetsky","year":"2005","journal-title":"Appl. Phys. Lett."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1710","DOI":"10.1364\/OL.32.001710","article-title":"All-fiber add-drop filters based on microfiber knot resonators","volume":"32","author":"Jiang","year":"2007","journal-title":"Opt. Lett."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"101126","DOI":"10.1063\/1.2898211","article-title":"Demonstration of a refractometric sensor based on optical microfiber coil resonator","volume":"92","author":"Xu","year":"2008","journal-title":"Appl. Phys. Lett."},{"key":"ref_14","first-page":"100026","article-title":"Fiber-based early diagnosis of venous thromboembolic disease by label-free D-dimer detection","volume":"2","author":"Zubiate","year":"2019","journal-title":"Biosens. Bioelectron. X"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Pan, Z., Huang, Y., and Xiao, H. (2018). Multi-Parameter Sensing Device to Detect Liquid Layers Using Long-Period Fiber Gratings. Sensors, 18.","DOI":"10.3390\/s18093094"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Janik, M., Koba, M., Kr\u00f3l, K., Mikulic, P., Bock, J.W., and \u015amietana, M. (2020). Combined Long-Period Fiber Grating and Microcavity In-Line Mach\u2013Zehnder Interferometer for Refractive Index Measurements with Limited Cross-Sensitivity. Sensors, 20.","DOI":"10.3390\/s20082431"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Torres-G\u00f3mez, I., Ceballos-Herrera, E.D., and Salas-Alcantara, M.K. (2020). Mechanically-Induced Long-Period Fiber Gratings Using Laminated Plates. Sensors, 20.","DOI":"10.3390\/s20092582"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1002\/jbio.201200135","article-title":"Characterisation of a label-free biosensor based on long period grating","volume":"7","author":"Chiavaioli","year":"2014","journal-title":"J. Biophotonics"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1016\/j.bios.2017.03.004","article-title":"Graphene oxide functionalized long period grating for ultrasensitive label-free immunosensing","volume":"94","author":"Liu","year":"2017","journal-title":"Biosens. Bioelectron."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/j.snb.2018.01.117","article-title":"Graphene oxide functionalized long period fiber grating for highly sensitive hemoglobin detection","volume":"261","author":"Liu","year":"2018","journal-title":"Sens. Actuators B Chem."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"15793","DOI":"10.1364\/OE.391889","article-title":"Development of an optical microfiber immunosensor for prostate specific antigen analysis using a high-order-diffraction long period grating","volume":"28","author":"Xiao","year":"2020","journal-title":"Opt. Express"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.bios.2019.03.006","article-title":"Ultrasensitive tantalum oxide nano-coated long-period gratings for detection of various biological targets","volume":"133","author":"Dominik","year":"2019","journal-title":"Biosens. Bioelectron."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/j.bios.2019.03.024","article-title":"Label-free detection of Staphylococcus aureus bacteria using long-period fiber gratings with functional polyelectrolyte coatings","volume":"133","author":"Yang","year":"2019","journal-title":"Biosens. Bioelectron."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.snb.2017.04.148","article-title":"Long-period fiber grating sensor for detection of viruses","volume":"250","author":"Dominik","year":"2017","journal-title":"Sens. Actuators B Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1016\/j.bios.2016.02.021","article-title":"Long period fiber grating nano-optrode for cancer biomarker detection","volume":"80","author":"Quero","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1394","DOI":"10.1002\/adma.201504021","article-title":"Rapid 3D Patterning of Poly(acrylic acid) Ionic Hydrogel for Miniature pH Sensors","volume":"28","author":"Yin","year":"2016","journal-title":"Adv. Mater."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Wang, Y., Liu, Y., Zou, F., Jiang, C., Mou, C., and Wang, T. (2019). Humidity Sensor Based on a Long-Period Fiber Grating Coated with Polymer Composite Film. Sensors, 19.","DOI":"10.3390\/s19102263"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1016\/j.snb.2016.01.058","article-title":"A long period grating optical fiber sensor with nano-assembled porphyrin layers for detecting ammonia gas","volume":"228","author":"Wang","year":"2016","journal-title":"Sens. Actuators B Chem."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Hsu, H.-C., Hsieh, T.-S., Huang, T.-H., Tsai, L., and Chiang, C.-C. (2018). Double Notched Long-Period Fiber Grating Characterization for CO2 Gas Sensing Applications. Sensors, 18.","DOI":"10.3390\/s18103206"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1016\/j.bios.2015.12.089","article-title":"Long period fiber grating based sensor for the detection of triacylglycerides","volume":"79","author":"Baliyan","year":"2016","journal-title":"Biosens. Bioelectron."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"2482","DOI":"10.1364\/OL.44.002482","article-title":"Label-free cocaine aptasensor based on a long-period fiber grating","volume":"44","author":"Celebanska","year":"2019","journal-title":"Opt. Lett."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"100289","DOI":"10.1016\/j.sbsr.2019.100289","article-title":"Gold coated dual-resonance long-period fiber gratings (DR-LPFG) based aptasensor for cyanobacterial toxin detection","volume":"25","author":"Tripathi","year":"2019","journal-title":"Sens. Bio-Sens. Res."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Ran, Y., Hu, D., Xu, Z., Long, J., and Guan, B.-O. (2020). Vertical-fluid-array induced optical microfiber long period grating (VIOLIN) refractometer. J. Lightwave Technol.","DOI":"10.1109\/JLT.2020.2964769"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"6543","DOI":"10.1021\/ic200181p","article-title":"Reversible Fluorescent Probe for Highly Selective and Sensitive Detection of Mercapto Biomolecules","volume":"50","author":"Wu","year":"2011","journal-title":"Inorg. Chem."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"827","DOI":"10.3945\/ajcn.112.049932","article-title":"Homocysteine, cysteine, and risk of incident colorectal cancer in the Women\u2019s Health Initiative observational cohort","volume":"97","author":"Miller","year":"2013","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1039\/C4TB01354A","article-title":"A recyclable carbon nanoparticle-based fluorescent probe for highly selective and sensitive detection of mercapto biomolecules","volume":"3","author":"Lan","year":"2015","journal-title":"J. Mater. Chem. B"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"21433","DOI":"10.1038\/srep21433","article-title":"Determination of thiol metabolites in human urine by stable isotope labeling in combination with pseudo-targeted mass spectrometry analysis","volume":"6","author":"Liu","year":"2016","journal-title":"Sci. Rep."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.talanta.2016.04.031","article-title":"A versatile method for analysis of saliva, plasma and urine for total thiols using HPLC with UV detection","volume":"155","author":"Stachniuk","year":"2016","journal-title":"Talanta"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1109\/50.983240","article-title":"Sensitivity characteristics of long-period fiber gratings","volume":"20","author":"Xuewen","year":"2002","journal-title":"J. Lightwave Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"18577","DOI":"10.1364\/OE.19.018577","article-title":"193 nm excimer laser inscribed Bragg gratings in microfibers for refractive index sensing","volume":"19","author":"Ran","year":"2011","journal-title":"Opt. Express"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"7100208","DOI":"10.1109\/JPHOT.2013.2249504","article-title":"Temperature-Compensated Refractive-Index Sensing Using a Single Bragg Grating in an Abrupt Fiber Taper","volume":"5","author":"Ran","year":"2013","journal-title":"IEEE Photonics J."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"13472","DOI":"10.1021\/acs.analchem.7b03768","article-title":"Fabrication of Magnetic Conjugation Clusters via Intermolecular Assembling for Ultrasensitive Surface Plasmon Resonance (SPR) Detection in a Wide Range of Concentrations","volume":"89","author":"Lou","year":"2017","journal-title":"Anal. Chem."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Lou, Z., Han, H., Mao, D., Jiang, Y., and Song, J. (2018). Qualitative and Quantitative Detection of PrPSc Based on the Controlled Release Property of Magnetic Microspheres Using Surface Plasmon Resonance (SPR). Nanomaterials, 8.","DOI":"10.3390\/nano8020107"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"6345","DOI":"10.1021\/acs.analchem.9b01350","article-title":"Inverse Molecular Sentinel-Integrated Fiberoptic Sensor for Direct and in Situ Detection of miRNA Targets","volume":"91","author":"Strobbia","year":"2019","journal-title":"Anal. Chem."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"19567","DOI":"10.1039\/C6CP02353C","article-title":"Dynamics of a plasmon-activated p-mercaptobenzoic acid layer deposited over Au nanoparticles using time-resolved SERS","volume":"18","author":"Smith","year":"2016","journal-title":"Phys. Chem. Chem. Phys."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.snb.2019.01.167","article-title":"Fiber-optrode SERS probes using plasmonic silver-coated gold nanostars","volume":"287","author":"Ran","year":"2019","journal-title":"Sens. Actuators B Chem."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/12\/3415\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:39:58Z","timestamp":1760175598000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/12\/3415"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,6,17]]},"references-count":46,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2020,6]]}},"alternative-id":["s20123415"],"URL":"https:\/\/doi.org\/10.3390\/s20123415","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2020,6,17]]}}}