title: Hydrophobic solvent induced phase transition extraction to extract drugs from plasma for high performance liquid chromatography-mass spectrometric analysis.
abstract: Novel sample preparation approaches for HPLC bioanalysis based on the phenomenon that acetonitrile can be separated from water by adding salts or cooling at subzero temperatures have been reported. These two methods are superior to conventional liquid-liquid extraction since the separated acetonitrile phase can be directly injected to the RP-LC system. However, the salting-out method suffers from a potential problem that the remained salt in the acetonitrile phase may harm the MS detector, while the subzero-temperature method is troublesome to operate. Here, we have reported a similar phase separation phenomenon that the acetonitrile aqueous mixture can be separated by adding a hydrophobic solvent; and capitalising on this phase transition phenomenon, we have proposed an alternative approach, named solvent induced phase transition extraction (SIPTE), to extract drug from plasma for HPLC-MS analysis. The proposed SIPTE method is much simpler and avoids contaminating the MS detector. Three structurally diverse drugs were selected as test compounds to design the SIPTE method and to validate the efficiency of this method. The four goals of plasma sample pretreatment for HPLC-MS analysis, i.e. removal of proteins, removal of other low-molecular interferences, preconcentration of the analytes of interest, and matching the sample solvent with the HPLC-MS system, can be rapidly performed in a very simple step by using the SIPTE method.
authors: Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research, Ministry of Education, Hunan Normal University, Changsha 410081, China.
authors: Guozhu
authors: G
authors: Liu
authors: Naiyuan
authors: N
authors: Zhou
authors: Mingshan
authors: M
authors: Zhang
authors: Shengjun
authors: S
authors: Li
authors: Qingqing
authors: Q
authors: Tian
authors: Jitao
authors: J
authors: Chen
authors: Bo
authors: B
authors: Chen
authors: Yongning
authors: Y
authors: Wu
authors: Shouzhuo
authors: S
authors: Yao
mesh_terms: D000097:Acetonitriles / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D002725:Chloroform / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004224:Diterpenes / Q000097:blood / Q000302:isolation & purification; D018120:Finasteride / Q000097:blood / Q000302:isolation & purification; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D013058:Mass Spectrometry / Q000379:methods*; D008958:Models, Molecular; D004364:Pharmaceutical Preparations / Q000097:blood* / Q000302:isolation & purification; D010879:Piperazines / Q000097:blood / Q000302:isolation & purification; D011687:Purines / Q000097:blood / Q000302:isolation & purification; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000068677:Sildenafil Citrate; D013450:Sulfones / Q000097:blood / Q000302:isolation & purification
chemical_list: D000097:Acetonitriles; D004224:Diterpenes; D004364:Pharmaceutical Preparations; D010879:Piperazines; D011687:Purines; D013450:Sulfones; C030419:andrographolide; D018120:Finasteride; D002725:Chloroform; D000068677:Sildenafil Citrate; C032159:acetonitrile