title: A total analytical system featuring a novel solid-liquid extraction chamber for solid sample flow analysis.
abstract: In this work, a total flow analysis system based on a novel solid-liquid extraction chamber is presented. This strategy enables all the main experimental procedures for the analysis of a solid sample to be performed automatically: enrichment of the liquid extract, sample treatment, filtration of the liquid extract from the solid sample, directing the extract towards detection, and finally cleansing of the chamber for the following solid sample to be analyzed. The chamber designed to be incorporated in the flow manifold presents two main features: it accommodates stirring bars for enhancing the extraction process, and it presents replaceable solid sample containers (a spare part of the solid-liquid extraction chamber) to easily replace the solid sample and therefore enhance sample analysis throughput. The chamber performance was assessed using two different solid samples, an ion exchanger resin and vegetable samples, focussing on proton and nitrate ion extraction, respectively. The main figures of merit achieved were relative standard deviation (RSD) and relative error values below 7 % for all determinations. The determination rate for vegetable samples was ca. 12 samples h-1. The proposed strategy may be exploited to perform automatically the analysis of solid samples as it embodies a simple automatic strategy of a very important but time-consuming and laborious analytical operation. Graphical abstract TAS for solid liquid extraction and nitrate potentiometric determination of vegetable samples.
authors.affiliation: Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401, Porto, Portugal.
authors.forename: Andrea C
authors.initials: AC
authors.lastname: Galvis-Sánchez
authors.affiliation: Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401, Porto, Portugal. jrsantos@porto.ucp.pt.
authors.forename: João Rodrigo
authors.initials: JR
authors.lastname: Santos
authors.affiliation: Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Arquiteto Lobão Vital, Apartado 2511, 4202-401, Porto, Portugal.
authors.forename: António O S S
authors.initials: AO
authors.lastname: Rangel
mesh_terms: D001937:Brassica / Q000737:chemistry; D029688:Brassica napus / Q000737:chemistry; D028526:Coriandrum / Q000737:chemistry; D004987:Ethers / Q000737:chemistry; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007475:Ion Exchange Resins / Q000737:chemistry*; D018545:Lactuca / Q000737:chemistry; D059625:Liquid-Liquid Extraction / Q000295:instrumentation* / Q000379:methods; D009566:Nitrates / Q000302:isolation & purification*; D019697:Onions / Q000737:chemistry; D010618:Phenanthrolines / Q000737:chemistry; D011199:Potentiometry / Q000295:instrumentation / Q000379:methods; D011522:Protons; D052616:Solid Phase Extraction / Q000295:instrumentation* / Q000379:methods; D014675:Vegetables / Q000737:chemistry*
chemical_list: C519952:2-nitrophenyl octyl ether; D004987:Ethers; D007475:Ion Exchange Resins; D009566:Nitrates; D010618:Phenanthrolines; D011522:Protons
keywords: Automatic solid–liquid extraction; Low pressure flow analysis; Nitrate; Total analytical system; Vegetables