Voltammetry Applications Voltammetry Applications common electrodes mercury electrodes

Voltammetry Applications

Voltammetry – Applications common electrodes mercury electrodes DME – seldom used HMDE – frequently used still for SV; „classical standard“ film electrodes – used for SV GCE standard carbon electrode as support for film electrode for analytical purposes for rotating electrodes for mechanistic studies for modified electrodes Au, Pt less frequently used for analytical purposes for studies for SPEs occasionally used, more expensive for modified electrodes (e. g. , Au for SAM)

Voltammetry – Applications common electrodes heterogeneous carbon electrodes CPEs, SPCE very popular easy modification even with labile systems ideal for biosensors film electrodes Hg MFE „standard reference“ for other film electrodes Bi. FE getting very popular Sb. FE recently introduced Pb ibidem other types current trends carbon nanotubes B-doped diamond

Voltammetry – Applications practical applications inorganic analytes determination of total element concentration as laboratory techniques often replaced by other techniques AAS, ICP-MS as sensors determination of free ion concentrations possible with voltammetry direct determination for higher concentrations stripping voltammetry for lower concentrations

Voltammetry – Applications practical applications organic analytes determination via functional groups determination of organic compounds with mercury electrodes

Voltammetry – Applications environmental analysis stripping voltammetry – inorganic analytes heavy and toxic metals (Cu, Pb, Cd, Zn; As, Sb, Bi, Hg, Sn, Tl, U) in seawater, freshwater, rainwate, snow in marine and terrestrial organisms, plants, animals speciation analysis in water advantage: determination of free concentration particulate matter airborne particles rocks, minerals, sediments, coal fly ash typical AC stripping voltammogram of traces of tin in a rock sample

Voltammetry – Applications clinical analysis stripping voltammetry – inorganic and organic analytes body fluids (blood, serum, urine) determination of heavy metals after mineralization pressurized digestion low tempertaure ashing preferential PSA (no mineralization necessary) determination of some drugs thioamides adriamycin (anticancer drug) in urine chloropromazine (antipsychotic drug) in urine analysis of hair, tooth, eye tissue, bone determination of heavy metals assessment of exposures professional accidential, suicide attempts

Voltammetry – Applications example: heavy metals in whole blood (ashed samples) HMDE 10 min deposition, -0, 8 V 0, 21 ppb Cd 18, 6 ppb Pb 84, 2 ppb n. M Cu

Voltammetry – Applications example: heavy metals in urine HMDE 5 min deposition, -0, 8 V 4, 8 n. M Cd 26 n. M Pb 230 n. M Cu

Voltammetry – Applications example: chloropromazine in human urine sample diluted 1+3, successive concentration increments 1, 5 µM

Voltammetry – Applications clinical analysis biosensors most frequently glucose biosensor also available in pharmacies for personal use based on glucose oxidase other electrochemical biosensors not widespread basic problem enzyme stability shelf life time will be improved in the future stabilized modified enzymes occasionally used: LDH, Gl. Ox in vivo measurements – experimental, research directly – microelectrodes (experimental animals) neurotransmitters in brain microdialysis – humans, animals body fluids

Voltammetry – Applications food analysis determination of trace metals still popular Cd, Pb, Hg, in the focus of interest determination of organic compounds herbicides, pesticides often indirectly by inhibition of enzymes determination of biologically important compounds alcohols, aldehydes, acids biosensors with oxidases, dehydrogenases carbohydrates biosensors with oxidases phenols, antioxidant capacity biosensors with oxidases amines biosensors with oxidases

Voltammetry – Applications forensic analysis determination of gunpowder residues elemental composítion Sb, Pb, Cu, Ba (MFE) „elemental fingerprints“ of gunshot residue Stripping voltammograms of gunshot residue (1) gunshot residue (2) blank (3) blank + 30 ng Sb