title: Application of super-resolution reconstruction of sparse representation in mass spectrometry imaging.
abstract: BACKGROUND
  Mass Spectrometry Imaging (MSI) is useful for analyzing biological samples directly, as a spatially resolved, label-free technique. Here we present a method for super-resolution reconstruction of sparse representation to improve resolution of MSI data.
  
  
  METHODS
  Air Flow-Assisted Ionization Mass Spectrometry Imaging (AFAI-MSI) was used to acquire MSI data from ink samples, thyroid tumour samples, rat renal biopsies, and rat brain biopsy samples. Super-resolution reconstruction of sparse representation was adopted for the collected MSI data.
  
  
  RESULTS
  After comparison of the reconstructed high-resolution image and the original high-resolution image, it is found that super-resolution reconstruction image is closer to the original high-resolution image than the image obtained with the interpolation method, and the highest Peak Signal-to-Noise Ratio (PSNR) difference value is over 1.4dB. Therefore, the application of the super-resolution reconstruction technique, based on sparse representation MSI, is feasible and effective.
  
  
  CONCLUSIONS
  The method proposed here not only improves the resolution of MSI in post-data processing, but also acquires fewer sampling points at the same resolution, thereby greatly reducing the sampling time, with great application value for large-volume sample MSI, high-resolution MSI, etc.
authors.affiliation: State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Bi
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
authors.forename: Jiuming
authors.initials: J
authors.lastname: He
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
authors.forename: Tiegang
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100050, China.
authors.forename: Zeper
authors.initials: Z
authors.lastname: Abliz
authors.affiliation: State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Beijing, 100084, China.
authors.forename: Xiaohao
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D001921:Brain; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007668:Kidney / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D051381:Rats; D059629:Signal-To-Noise Ratio