title: Differential pulse anodic voltammetric determination of lithium ions in pharmaceutical formulations using a carbon paste electrode modified with spinel-type manganese oxide.
abstract: The use of the differential pulse voltammetry for the determination of lithium ions in pharmaceutical samples using a carbon paste electrode modified with spinel-type manganese oxide has been examined. The best voltammetric response was reached for a modified electrode in borate buffer solution of pH 9.0 and submitted to a scan rate of 5 mV s(-1) and a pulse amplitude of 50 mV. This electroanalytical procedure was able to determine lithium ions in the concentration range of 8.0 x 10(-5)-1.0 x 10(-2) mol l(-1) even in the presence of several alkali metals (1.0 x 10(-3) mol l(-1)) with a detection limit of 7.1 x 10(-7) mol l(-1). Rapidity, precise and good selectivity were also found for the determination of lithium ions in pharmaceutical formulations.
authors.affiliation: Grupo de Quimica Analítica, Departamento de Química, Centro de Ciências Exatas e de Tecnologia, Universidade Federal de São Carlos, Caixa Postal 676, Via Washington Luiz, CEP 13 560-970 São Carlos, SP, Brazil. funcao@dq.ufscar.br
authors.forename: Marcos F S
authors.initials: MF
authors.lastname: Teixeira
authors.forename: Fernando C
authors.initials: FC
authors.lastname: Moraes
authors.forename: Eder T G
authors.initials: ET
authors.lastname: Cavalheiro
authors.forename: Nerilso
authors.initials: N
authors.lastname: Bocchi
mesh_terms: D002138:Calibration; D004563:Electrochemistry; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007477:Ions; D008094:Lithium / Q000032:analysis* / Q000097:blood; D017895:Manganese Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D015203:Reproducibility of Results; D012996:Solutions; D013054:Spectrophotometry, Atomic
chemical_list: D007202:Indicators and Reagents; D007477:Ions; D017895:Manganese Compounds; D010087:Oxides; D012996:Solutions; C027424:manganese oxide; D008094:Lithium