1. Introduction
Fully automated analyzers perform analytical operations
without human interference. They perform complex
mechanical and electronic steps more precisely, rapidly,
and repeatably than classical analysis [1,2]. They require
minimal solution handling and give good accuracy and
reduce reagent consumption, reducing the cost per
determination [3,4]. Automated analyzers can be divided
into three groups: discrete or batch automatic analyzers,
robotic automatic analyzers, and automated low
analyzers [3,5-7]. The multicommutation low analysis
(MCFA) proposed by Reis et al. [6] has all the capabilities
necessary. Three-way solenoid valves are used to select
the low path, allowing pumping and sample and reagent
insertion into the carrier solution. The injected volume
is controlled by the interval that the valves are open
and the low rate. In MCFA, different analyses can be
designed by inserting new devices such as reactors and
ion-exchange columns into the low path [8,9].
Solid-phase reactors (SPR) conine solid reagents in
the low path. They are widely used for pre-concentration,
interferent removal, or to convert the analyte to a
detectable species using immobilized reagents such
as enzymes or macromolecules [10,11]. More effective
contact with the analyte can increase the and compact
Central European Journal of Chemistry
A low-cost automated low analyzer based
on low temperature co-ired ceramic and LED
photometer for ascorbic acid determination
* E-mail: rcfaria@ufscar.br
Received 7 October 2013; Accepted 3 November 2013
Abstract:
© Versita Sp. z o.o.
Keywords: Ascorbic acid determination • Flow analysis • LTCC • LED photometer • Multicommutation.
1
Chemistry Department, Center of Exact Sciences and Technology,
Federal University of São Carlos,
13565-905 São Carlos-SP, Brazil
2
Chemistry Department, Exact and Technological Sciences Center,
Federal University of Viçosa,
36570-000, Viçosa-MG, Brazil
3
Group of Sensors and Biosensors,
Department of Chemistry, Autonomous
University of Barcelona, Ediici Cn, 08193 Bellaterra, Spain
Osmundo D. Pessoa-Neto
1
, Vagner B. dos Santos
1
,
Fernando C. Vicentini
1
, Willian T. Suarez
2
,
Julián Alonso-Chamarro
3
, Orlando Fatibello-Filho
1
, Ronaldo C. Faria
1*
Research Article
An automated low analyzer based on low temperature co-ired ceramic (LTCC), a solid-phase reactor (SPR) and a low-cost photometer
was designed for ascorbic acid (AA) determination in pharmaceutical formulations. It consists of a peristaltic pump, three-way
solenoid valves, SPR to chemically convert Cu(II) into Cu(I), and a LTCC device for mixing the liberated copper with bathocuproine
and detection. The low cell in the LTCC employed an ultrabright LED - photodiode photometer. The analyzer successfully determined
AA in pharmaceutical formulations. The analytical curve from 8.5×10
−6
to 7.0×10
−4
M gave a detection limit of 7.0×10
−7
M and a
RSD of 2.1% for a 2.0×10
−4
M AA solution (n = 10). A high sampling frequency of 102 h
−1
and low reagent and sample consumption
(150 µL) resulted.
Cent. Eur. J. Chem. • 12(3) • 2014 • 341-347
DOI: 10.2478/s11532-013-0377-2
341