title: Application of packed-fiber solid-phase extraction coupled with GC-MS for the determination of short-chain fatty acids in children's urine.
abstract: BACKGROUND
  Autism spectrum disorder (ASD) is a complex disorder involving interactions between genetic, epigenetic and environmental factors. Gastrointestinal (GI) disorders are prevalent in the cohort of children with ASD and they have been recognized as a comorbid condition recently. It is of value to monitor GI issues in individuals, and to help further characterize factors that may contribute to GI disorders (in individuals with and without ASD). Due to the biological relevance of short-chain fatty acids (SCFAs) to GI disorders, it is important to develop a rapid and selective detection method capable of identifying and quantifying SCFAs in complex biological samples. Because of low concentration and hydrophilicity of SCFAs, the pretreatment of sample becomes the key step to detection method. We erected and verified a packed-fiber solid-phase extraction (PFSPE) based on Polypyrrole (PPY) nanofibers coupled with gas chromatography-mass spectrometry (GC-MS) to determine SCFAs in urine. The proposed method was applied to detect SCFAs in urine from children with and without ASD, and the results between the 2 groups was compared.
  
  
  METHODS
  PFSPE method was utilized for the direct pretreatment of SCFAs in urine from children. The SCFAs extracted on nanofibers was subsequently eluted with hydrochloric acid ethanol solution and detected by GC-MS.
  
  
  RESULTS
  Intraday and interday assay CVs were ≤10%, and the recoveries was 82.6%-110.5%. Limit of detection (LOD) and limit of quantification (LOQ) were 0.25-2.67ng/ml and 0.85-8.97ng/ml, respectively. The level of SCFAs in urine from children with ASD were significantly higher than that from control group.
  
  
  CONCLUSIONS
  The proposed method improves the simplification of sample treatment and displays sufficient analytical sensitivity and selectivity. The assay offers a potential to monitor the SCFAs in urine in clinical and experimental investigation of ASD.
authors.affiliation: Key Laboratory of Child Development and Learning Science (Ministry of Education), Research Center for Learning Science, Southeast University, Nanjing 210096, China.
authors.forename: Renshan
authors.initials: R
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Environmental Medicine and Engineering (Ministry of Education), School of Public Health, Southeast University, Nanjing 210009, China.
authors.forename: Lanling
authors.initials: L
authors.lastname: Chu
authors.affiliation: Key Laboratory of Child Development and Learning Science (Ministry of Education), Research Center for Learning Science, Southeast University, Nanjing 210096, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Division of Child Care, Suzhou Municipal Hospital, Suzhou 215002, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Song
authors.affiliation: Division of Child Care, Suzhou Municipal Hospital, Suzhou 215002, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.affiliation: Key Laboratory of Child Development and Learning Science (Ministry of Education), Research Center for Learning Science, Southeast University, Nanjing 210096, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Li
authors.affiliation: Key Laboratory of Child Development and Learning Science (Ministry of Education), Research Center for Learning Science, Southeast University, Nanjing 210096, China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Huang
authors.affiliation: Key Laboratory of Child Development and Learning Science (Ministry of Education), Research Center for Learning Science, Southeast University, Nanjing 210096, China; Key Laboratory of Environmental Medicine and Engineering (Ministry of Education), School of Public Health, Southeast University, Nanjing 210009, China. Electronic address: xjkang64@163.com.
authors.forename: Xuejun
authors.initials: X
authors.lastname: Kang
mesh_terms: D000067877:Autism Spectrum Disorder / Q000652:urine; D016022:Case-Control Studies; D002648:Child; D005227:Fatty Acids / Q000737:chemistry / Q000302:isolation & purification* / Q000652:urine*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D008297:Male; D052616:Solid Phase Extraction / Q000379:methods*; D016482:Urinalysis / Q000379:methods*
chemical_list: D005227:Fatty Acids
keywords: Autism spectrum disorder; GC–MS; PFSPE; Short-chain fatty acids