title: Droplet-based glucosamine sensor using gold nanoparticles and polyaniline-modified electrode.
abstract: A droplet-based electrochemical sensor for direct measurement of D-glucosamine was developed using carbon paste electrodes (CPEs) modified with gold nanoparticles (AuNPs) and polyaniline (PANI). Central composition design (CCD) was employed as a powerful method for optimization of parameters for electrode fabrication. The optimized amounts of AuNPs and PANI obtained from the response surface were determined as 300 and 3000mgL(-1), respectively. Coupled with a droplet microfluidic system, the analysis of glucosamine was performed in a high-throughput manner with a sample throughput of at least 60 samples h(-1). In addition, the adsorption of the analyte on the electrode surface was prevented due to compartmentalization in droplets. Linearity of the proposed system was found to be in the range of 0.5-5mM with a sensitivity of 7.42×10(-3)Amol(-1)Lcm(-2) and limits of detection and quantitation of 0.45 and 1.45mM, respectively. High intraday and interday (evaluated among 3 days) precisions for the detection of 50 droplets containing glucosamine were obtained with relative standard deviation less than 3%. The system was successfully used to determine the amounts of glucosamine in supplementary products with error percentage and relative standard deviation less than 3%. In addition, the amounts of glucosamine measured using the developed sensor were in good agreement with those obtained from a CE method. These indicate high accuracy and precision of the proposed system.
authors.affiliation: Chromatography and Separation Research Unit (ChSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Akkapol
authors.initials: A
authors.lastname: Suea-Ngam
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Poomrat
authors.initials: P
authors.lastname: Rattanarat
authors.affiliation: Nanotec-CU Center of Excellence on Food and Agriculture, Faculty of Science, Department of Chemistry, Chulalongkorn University, Bangkok, 10330, Thailand.
authors.forename: Kanet
authors.initials: K
authors.lastname: Wongravee
authors.affiliation: Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; National Center of Excellence on Petrochemical and Materials Technology, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Orawon
authors.initials: O
authors.lastname: Chailapakul
authors.affiliation: Chromatography and Separation Research Unit (ChSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand; Electrochemistry and Optical Spectroscopy Research Unit (EOSRU), Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand. Electronic address: monpichar.s@chula.ac.th.
authors.forename: Monpichar
authors.initials: M
authors.lastname: Srisa-Art
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D055664:Electrochemical Techniques; D004566:Electrodes; D005944:Glucosamine / Q000032:analysis* / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D056656:Lab-On-A-Chip Devices; D053768:Metal Nanoparticles / Q000737:chemistry*
chemical_list: D000814:Aniline Compounds; C416807:polyaniline; D006046:Gold; D005944:Glucosamine
keywords: Carbon paste electrode; Central composition design, chronoamperometry; Droplet-based microfluidics; Glucosamine