PMID- 12477186
OWN - NLM
STAT- MEDLINE
DCOM- 20030515
LR  - 20190729
IS  - 1060-3271 (Print)
IS  - 1060-3271 (Linking)
VI  - 85
IP  - 6
DP  - 2002 Nov-Dec
TI  - Sequential determination of salicylic and acetylsalicylic acids by amperometric 
      multisite detection flow injection analysis.
PG  - 1253-9
AB  - An amperometric multisite detection flow injection analysis (FIA) system was 
      developed for sequential determination of 2 analytes with a single sample 
      injection and single detector. Tubular composite carbon electrodes with an inner 
      diameter similar to that of the FIA manifold tubing were constructed so that 
      measurements could be made without impairing the sample plug hydrodynamic 
      characteristics. The electrochemical behavior of the tubular voltammetric cell in 
      a low-dispersion FIA manifold and the behavior of the FIA system incorporating 
      this type of voltammetric cell intended for multisite detection were evaluated by 
      performing measurements with potassium hexacyanoferrate(II). Feasibility of the 
      approach was demonstrated in the sequential determination of salicylic and 
      acetylsalicylic acids in pharmaceutical products at a fixed potential of 0.98 V. 
      The system allows sequential determination of salicylic acid concentrations 
      ranging from 1.0 x 10(-5) to 5.0 x 10(-5) M and acetylsalicylic acid 
      concentrations between 1.0 x 10(-3) and 5.0 x 10(-3) M with good precision on 
      both detection sites and with relative standard deviations (RSDs) > or = 1.5% (n 
      = 10) and 2.1% (n = 10), respectively. A comparison of these results with those 
      of the U.S. Pharmacopeia procedure showed RSDs <5.0 and 1.0% for salicylic acid 
      and acetylsalicylic acid, respectively. The proposed method enables 15 
      determinations per hour, which corresponds to the analysis of approximately 8 
      samples per hour. The detection limits of the methodology were approximately 3.5 
      x 10(-6) and 1.1 x 10(-5) M, respectively, for the first and second monitoring 
      sites.
FAU - Catarino, Rita I L
AU  - Catarino RI
AD  - University of Porto, CEQUP/Department of Physical Chemistry, Faculty of Pharmacy, 
      Portugal.
FAU - Garcia, M Beatriz Q
AU  - Garcia MB
FAU - Lapa, Rui A S
AU  - Lapa RA
FAU - Lima, Jose L F C
AU  - Lima JL
FAU - Barrado, Enrique
AU  - Barrado E
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - J AOAC Int
JT  - Journal of AOAC International
JID - 9215446
RN  - 0 (Indicators and Reagents)
RN  - 0 (Solutions)
RN  - O414PZ4LPZ (Salicylic Acid)
RN  - R16CO5Y76E (Aspirin)
SB  - IM
MH  - Aspirin/*analysis
MH  - Chromatography, Gas
MH  - Chromatography, Liquid
MH  - Colorimetry
MH  - Electrochemistry
MH  - Electrodes
MH  - Flow Injection Analysis
MH  - Fluorometry
MH  - Indicators and Reagents
MH  - Portugal
MH  - Salicylic Acid/*analysis
MH  - Solutions
MH  - Spectrophotometry, Infrared
MH  - Spectrum Analysis, Raman
EDAT- 2002/12/13 04:00
MHDA- 2003/05/16 05:00
CRDT- 2002/12/13 04:00
PHST- 2002/12/13 04:00 [pubmed]
PHST- 2003/05/16 05:00 [medline]
PHST- 2002/12/13 04:00 [entrez]
PST - ppublish
SO  - J AOAC Int. 2002 Nov-Dec;85(6):1253-9.