Indirect Anodic Stripping Voltammetric Determination of Tl(I) and Tl(III) in the Baltic Seawater Samples Enriched in Thallium Species

Abstract

The sensitive method DPASV with HMDE in the presence of DTPA and acetic buffer was used for determination of Tl(I) and Tl(III) in spiked seawater sample. The proposed method was based on the appropriate chemical conservation of Tl speciation. To determine the total amount of Tl, an addition of ascorbic acid to sub-sample was necessary, but to determine Tl(I) to the second sub-sample addition of DTPA was needed. Various factors influencing the stability of Tl(III) and electrochemical parameters were investigated. The quantification limit of 1.8 ng mL À1 Tl(I) was found for 8 min preconcentration. The procedure was validated using recovery study and HPLC ICP MS determinations.

TlI and TlIII presence in suspended particulate matter: speciation analysis of thallium in wastewater

“…*Tl*is*more*stable*in*its*monovalent*state*than*in*the*trivalent*state;*therefore,* standard*reduction*potential*(E red )*of*Tl III *to*Tl I *(E red *(Tl 3+ /Tl + )*=*+1.26*V)*and*also*hydrolysis*of*Tl III *at*pH*<*7* can*be*observed*in*water*samples. [37] * Thallium(III)*in*the*chloride*complex*is*reduced*up*to*40*%,*in*the*complex*with*acetates*up*to*80*%*and* in*the*DTPA*complex*just*up*to*1-3*%. [36] *Furthermore,*precipitation*of*thallium*hydroxide*is*observed*in* aqueous*solutions*at*pH*³*5.…”

Contactless Conductivity Detection of 14 Inorganic Cations in Mineral and Phytotherapeutic Formulations after Capillary Electrophoretic Separation

“…Considering now the separation of Tl from K ions after the addition of citric acid, it is important to take into account that both Tl + and Tl 3 + species might be present in the medium, since Tl 3 + can be spontaneously reduced to Tl + due to the highly positive standard reduction potential of the couple Tl 3 + /Tl + (E red = + 1,26 V) [35]. However, digested samples should present, in principle, only Tl 3 + species, since a highly oxidizing mixture (HNO 3 / H 2 O 2 ) is used in the digestion procedure.…”

Detection of Oxidative Damage of Synthetic Oligonucleotides Caused by Thallium(III) Complexes

“…The extremely fast, spontaneous reduction of Tl(III) to Tl(I) (log K =40, E °(Tl 3+ /Tl + )=+1.26 V) is much faster than the complexation of Tl(III). Therefore, the partial reduction is always observed 10. Thallium(III) in the chloride complex was reduced up to 40 %, in the complex with acetates up to 80 % and in the DTPA complex just up to 1–3 %.…”