PMID- 28599859
OWN - NLM
STAT- MEDLINE
DCOM- 20171102
LR  - 20191210
IS  - 1873-3778 (Electronic)
IS  - 0021-9673 (Linking)
VI  - 1507
DP  - 2017 Jul 21
TI  - Simultaneous determination of the lipophilicity and dissociation constants of 
      dialkyl phosphinic acids by negligible depletion hollow fiber membrane-protected 
      liquid-phase microextraction.
PG  - 11-17
LID - S0021-9673(17)30835-X [pii]
LID - 10.1016/j.chroma.2017.06.002 [doi]
AB  - Determination of the physicochemical properties, especially the lipophilicity 
      (expressed as the logarithm of distribution coefficient, log D) and dissociation 
      constant (pK(a)), is of great importance in the early stage of environmental risk 
      assessment for an ionizable compound without these data. Currently, the log D and 
      pK(a) values of dialkyl phosphinic acids (DPAs), the environmental hydrolysates 
      of aluminum dialkyl phosphinates (ADPs) that is one class of emerging 
      phosphorus-containing flame retardants, are not available. In this study, the log 
      D and pK(a) values of three DPAs including methylethylphosphinic acid (MEPA), 
      diethylphosphinic acid (DEPA) and methylcyclohexyl phosphinic acid (MHPA), were 
      simultaneously determined by negligible depletion hollow fiber supported liquid 
      phase microextraction (nd-HF-LPME) followed by ultra-performance liquid 
      chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). The pK(a) and 
      log D of DPAs were determined by curve-fitting the experimental data with 
      equations derived on the basis of the Henderson-Hasselbalch equation and compared 
      with model calculated data. For MEPA, DEPA and MHPA, the pK(a) values were close 
      and around 3, but the log Ds were strongly pH-dependent with values from -5.01 to 
      1.01. The log K(OW) of the neutral form (logK(OW,HA)) and ionic form (logK(OW,A)) 
      were in the range of -0.67-1.02 and -3.86--1.33, respectively. The experimentally 
      determined pK(a) values were highly in good agreement with ACD/pK(a) predicted 
      values and the measured log K(OW,HA) values were closely related to KOWWIN 
      calculated ones, suggesting ACD/pK(a) and KOWWIN are good alternative methods to 
      estimate pK(a) and log K(OW) of DPAs, respectively. As far as we know, this is 
      the first report on the pK(a) and log D data for DPAs, which are fundamental for 
      the product design and evaluating the environmental behavior and effects of DPAs 
      and ADPs.
CI  - Copyright (c) 2017 Elsevier B.V. All rights reserved.
FAU - Shi, Fengqiong
AU  - Shi F
AD  - State Key Laboratory of Environmental and Ecotoxicology, Research Center for 
      Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; 
      University of Chinese Academy of Sciences, Beijing 100049, China.
FAU - Liu, Jingfu
AU  - Liu J
AD  - State Key Laboratory of Environmental and Ecotoxicology, Research Center for 
      Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; 
      University of Chinese Academy of Sciences, Beijing 100049, China. Electronic 
      address: jfliu@rcees.ac.cn.
LA  - eng
PT  - Evaluation Study
PT  - Journal Article
DEP - 20170602
PL  - Netherlands
TA  - J Chromatogr A
JT  - Journal of chromatography. A
JID - 9318488
RN  - 0 (Flame Retardants)
RN  - 0 (Phosphinic Acids)
SB  - IM
MH  - Chromatography, Liquid/methods
MH  - Flame Retardants/analysis/*isolation & purification
MH  - Kinetics
MH  - Liquid Phase Microextraction/instrumentation/*methods
MH  - Phosphinic Acids/chemistry/*isolation & purification
MH  - Tandem Mass Spectrometry/methods
OTO - NOTNLM
OT  - Dialkyl phosphinic acids (DPAs)
OT  - Dissociation constant (pK(a))
OT  - Hollow fiber
OT  - Lipophilicity (log D)
OT  - UPLC-MS/MS
EDAT- 2017/06/11 06:00
MHDA- 2017/11/03 06:00
CRDT- 2017/06/11 06:00
PHST- 2017/04/20 00:00 [received]
PHST- 2017/05/31 00:00 [revised]
PHST- 2017/06/01 00:00 [accepted]
PHST- 2017/06/11 06:00 [pubmed]
PHST- 2017/11/03 06:00 [medline]
PHST- 2017/06/11 06:00 [entrez]
AID - S0021-9673(17)30835-X [pii]
AID - 10.1016/j.chroma.2017.06.002 [doi]
PST - ppublish
SO  - J Chromatogr A. 2017 Jul 21;1507:11-17. doi: 10.1016/j.chroma.2017.06.002. Epub 
      2017 Jun 2.