Application of lactate amperometric sol-gel biosensor to sequential injection determination of L-lactate.
This work describes the construction and evaluation of lactate sol-gel biosensors to accomplish the determination of lactate in pharmaceutical products. Lactate oxidase was incorporated in a porous sol-gel film placed onto a platinum-based electrode. Acid and basic catalysis were assessed. When coupled to a sequential injection system (SIA) the biosensor, based on (3-aminopropyl)trimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyl-trimethoxysilane, deionised water, polyethylene glycol 6000 and acid catalyst, presented a range of linearity of 5x10(-5) to 5x10(-3)M. The analytical usefulness of the developed biosensor was evaluated through analysis of commercial pharmaceutical products containing lactate with a sampling rate of 40 samples h(-1). The enzyme remained active for at least 30 days, enabling about 700 determinations without sensitivity decrease.
Gomes
Sofia Piedade
SP
REQUIMTE, Departamento de Química-Física, Faculdade de Farmácia, Universidade do Porto, Rua Anibal Cunha, 164, 4099-030 Porto, Portugal.
Odlozilíková
Martina
M
Almeida
M Gabriela
MG
Araújo
Alberto N
AN
Couto
Cristina M C M
CM
Montenegro
M Conceição B S M
MC
D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D004563:Electrochemistry; D004800:Enzymes, Immobilized / Q000032:analysis* / Q000737:chemistry; D005782:Gels; D007700:Kinetics; D019344:Lactic Acid / Q000032:analysis* / Q000737:chemistry; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000737:chemistry; D044367:Phase Transition
D004800:Enzymes, Immobilized; D005782:Gels; D004364:Pharmaceutical Preparations; D019344:Lactic Acid