{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,13]],"date-time":"2025-11-13T07:26:10Z","timestamp":1763018770548,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,9,26]],"date-time":"2024-09-26T00:00:00Z","timestamp":1727308800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2021YFC2103300"],"award-info":[{"award-number":["2021YFC2103300"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In many research fields, the demand for miniaturized laser-induced fluorescence (LIF) detection systems has been increasing. This work has developed a compact LIF detector, employing a laser diode as the excitation source and a photodiode as the photodetector with an adjustable laser focal spot, to meet the diverse requirements of various observation targets, such as capillaries, PCR tubes, and microfluidic chips. It features the functionalities of background fluorescence correction, the adaptive adjustment of the dynamic range, and constant power control for the laser. The influence of the excitation power on the detection limit was studied through experiments, and the configuration results for LED\/LD as light sources and 487\/450 nm wavelengths were compared and optimized. A fully integrated, compact, modular epifluorescence LIF detector was subsequently constructed, measuring 40 \u00d7 22 \u00d7 38 mm3 in total size, with a cost of USD 320, and achieving a detection limit of 0.4 nM for fluorescein sodium. Finally, the detector was integrated into a nucleic acid detection system with a microfluidic chip on the Chinese Space Station (CSS) and was also tested with PCR tubes and capillaries, proving its broad practicality and adaptability to various analytical systems.<\/jats:p>","DOI":"10.3390\/s24196224","type":"journal-article","created":{"date-parts":[[2024,9,26]],"date-time":"2024-09-26T08:20:52Z","timestamp":1727338852000},"page":"6224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Compact Laser-Induced Fluorescence Detector with Adjustable Laser Focal Spot for Multiple Purposes"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-5402-570X","authenticated-orcid":false,"given":"Zihe","family":"Xu","sequence":"first","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-4808-0088","authenticated-orcid":false,"given":"Xi","family":"Chen","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Atmospheric Particle Pollution Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fangwu","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.jchromb.2013.04.028","article-title":"Recent developments and applications of capillary electrophoresis with laser-induced fluorescence detection in biological samples","volume":"929","author":"Ban","year":"2013","journal-title":"J. Chromatogr. B"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1016\/j.talanta.2019.03.093","article-title":"7-(Diethylamino)coumarin-3-carboxylic acid as derivatization reagent for 405 nm laser-induced fluorescence detection: A case study for the analysis of sulfonamides by capillary electrophoresis","volume":"201","author":"Wu","year":"2019","journal-title":"Talanta"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3305","DOI":"10.1007\/s00216-010-3595-x","article-title":"Capillary array isoelectric focusing with laser-induced fluorescence detection: Milli-pH unit resolution and yoctomole mass detection limits in a 32-channel system","volume":"397","author":"Dada","year":"2010","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"8203","DOI":"10.1021\/acs.analchem.1c00484","article-title":"Two-Dimensional Cytometry Platform for Single-Particle\/Cell Analysis with Laser-Induced Fluorescence and ICP\u2013MS","volume":"93","author":"Wu","year":"2021","journal-title":"Anal. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"124424","DOI":"10.1016\/j.talanta.2023.124424","article-title":"Open flow cytometer with the combination of 3D hydrodynamic single cell focusing and confocal laser-induced fluorescence detection","volume":"258","author":"Wu","year":"2023","journal-title":"Talanta"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1007\/s00216-001-1125-6","article-title":"A laser-induced fluorescence dual-fiber optic array detector applied to the rapid HPLC separation of polycyclic aromatic hydrocarbons","volume":"372","author":"Hart","year":"2002","journal-title":"Anal. Bioanal. Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"976421","DOI":"10.1100\/2012\/976421","article-title":"Application of HPLC Combined with Laser Induced Fluorescence for Protein Profile Analysis of Tissue Homogenates in Cervical Cancer","volume":"2012","author":"Bhat","year":"2012","journal-title":"Sci. World J."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"085701","DOI":"10.1088\/1361-6501\/aa7810","article-title":"Laser-induced fluorescence detection platform for point-of-care testing","volume":"28","author":"Berner","year":"2017","journal-title":"Meas. Sci. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"709","DOI":"10.1016\/j.proeng.2011.12.175","article-title":"Laser-induced fluorescence detection modules for point-of- care microfluidic biochemical analysis","volume":"25","author":"Kamei","year":"2011","journal-title":"Procedia Eng."},{"key":"ref_10","unstructured":"Balasubramanian, K., and Burghard, M. (2010). Carbon Nanotubes as Intracellular Carriers for Multidrug Resistant Cells Studied by Capillary Electrophoresis\u2013Laser\u2013Induced Fluorescence. Carbon Nanotubes: Methods and Protocols, Humana Press."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3591","DOI":"10.1002\/elps.200900077","article-title":"Optimization of urinary pteridine analysis conditions by CE-LIF for clinical use in early cancer detection","volume":"30","author":"Gibbons","year":"2009","journal-title":"Electrophoresis"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"2075","DOI":"10.1002\/elps.201600090","article-title":"A CIEF-LIF method for simultaneous analysis of multiple protein kinases and screening of inhibitors","volume":"37","author":"Xiao","year":"2016","journal-title":"Electrophoresis"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"240","DOI":"10.1016\/j.talanta.2016.12.056","article-title":"Confocal laser-induced fluorescence detector for narrow capillary system with yoctomole limit of detection","volume":"165","author":"Weaver","year":"2017","journal-title":"Talanta"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.talanta.2015.12.018","article-title":"A handheld laser-induced fluorescence detector for multiple applications","volume":"150","author":"Fang","year":"2016","journal-title":"Talanta"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1016\/j.talanta.2018.01.076","article-title":"A compact and low-cost laser induced fluorescence detector with silicon based photodetector assembly for capillary flow systems","volume":"182","author":"Geng","year":"2018","journal-title":"Talanta"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Pan, J.-Z., Fang, P., Fang, X.-X., Hu, T.-T., Fang, J., and Fang, Q. (2018). A Low-Cost Palmtop High-Speed Capillary Electrophoresis Bioanalyzer with Laser Induced Fluorescence Detection. Sci. Rep., 8.","DOI":"10.1038\/s41598-018-20058-0"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"122329","DOI":"10.1016\/j.talanta.2021.122329","article-title":"Handheld laser-induced fluorescence detection systems with different optical configurations","volume":"230","author":"Peng","year":"2021","journal-title":"Talanta"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1016\/j.actaastro.2021.06.012","article-title":"A radiation tolerant laser-induced fluorescence detection system for a potential Europa Lander mission","volume":"186","author":"Oborny","year":"2021","journal-title":"Acta Astronaut."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"338936","DOI":"10.1016\/j.aca.2021.338936","article-title":"Native fluorescence detection with a laser driven light source for protein analysis in capillary electrophoresis","volume":"1183","author":"Zhu","year":"2021","journal-title":"Anal. Chim. Acta"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1593","DOI":"10.1007\/s10529-010-0332-7","article-title":"Linear dynamic range for signal detection in fluorescent differential display","volume":"32","author":"Cho","year":"2010","journal-title":"Biotechnol. Lett."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"744","DOI":"10.1016\/j.talanta.2009.07.060","article-title":"Six orders of magnitude dynamic range in capillary electrophoresis with ultrasensitive laser-induced fluorescence detection","volume":"80","author":"Whitmore","year":"2009","journal-title":"Talanta"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"664","DOI":"10.1039\/b602193j","article-title":"Low-picomolar limits of detection using high-power light-emitting diodes for fluorescence","volume":"131","author":"Lucy","year":"2006","journal-title":"Analyst"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1016\/j.aca.2016.06.015","article-title":"\u201cGetting the best sensitivity from on-capillary fluorescence detection in capillary electrophoresis\u201d\u2014A tutorial","volume":"935","author":"Galievsky","year":"2016","journal-title":"Anal. Chim. Acta"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Liu, F., Zheng, W., Tong, G., Zheng, W., Yuan, Y., Tian, Q., Xu, D., Jia, C., and Zhang, T. (2022, January 17\u201319). Experimental system of life ecological science on China Space Station. Proceedings of the Earth and Space: From Infrared to Terahertz (ESIT 2022), Nantong, China.","DOI":"10.1117\/12.2665052"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1007\/s12217-024-10125-9","article-title":"Development of the Microbial Online Monitoring Module (MOMM) for the Chinese Space Station","volume":"36","author":"Xu","year":"2024","journal-title":"Microgravity Sci. Technol."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/19\/6224\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:03:34Z","timestamp":1760112214000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/19\/6224"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,9,26]]},"references-count":25,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2024,10]]}},"alternative-id":["s24196224"],"URL":"https:\/\/doi.org\/10.3390\/s24196224","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2024,9,26]]}}}