title: The effect of the alternative solutions to formaldehyde and xylene on tissue processing.
abstract: OBJECTIVE
  To assess the impact of new alternative solutions to formaldehyde and xylene on tissue processing, 13 different tissue processings were designed and performed on thirteen different tissues by using five different fixatives (formaldehyde, Glyo-Fixx®, FineFix®, Cell-block®, Green-Fix®) and four different clearing agents (xylene, Sub-X®, Bio-clear®, Shandon Xylene Substitute®).
  
  
  METHODS
  Hematoxylin and Eosine stained sections were compared by using qualitative histomorphological criterions. Histochemical and immunohistochemical (IHC) staining results were compared with qualitative and quantitative data obtained by a computer program, respectively. Tissue sections were tested for the availability of chromogenic in situ hybridization, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) extraction, and DNA quality by polymerase chain reaction.
  
  
  RESULTS
  The quality of sections was well for all tissue processings. All alternative solutions were suitable for histochemistry. IHC staining results showed that alternative solutions that contain glyoxal as active agent need optimization for this application. The clearance of signals with chromogenic in situ hybridization were nearly same and well for all tissue samples. Furthermore, tissue processes that do not contain formaldehyde were found to be superior on preservation of nucleic acids.
  
  
  CONCLUSIONS
  Formaldehyde-free fixatives and alternative clearing agents have potential in routine pathology and research to replace formaldehyde and xylene.
authors.affiliation: Department of Pathology, School of Medicine, Dokuz Eylul University, Izmir, Turkey.
authors.forename: Ilgin
authors.initials: I
authors.lastname: Aydin
authors.forename: Kutsal
authors.initials: K
authors.lastname: Yörükoglu
authors.forename: Sultan
authors.initials: S
authors.lastname: Cingöz
authors.forename: Sinem
authors.initials: S
authors.lastname: Agilkaya
mesh_terms: D005404:Fixatives / Q000494:pharmacology*; D005557:Formaldehyde / Q000494:pharmacology; D006651:Histocytochemistry; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008853:Microscopy; D009696:Nucleic Acids / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D016707:Tissue Fixation / Q000379:methods*; D014992:Xylenes / Q000494:pharmacology
chemical_list: D005404:Fixatives; D009696:Nucleic Acids; D014992:Xylenes; D005557:Formaldehyde