title: EVA-enhanced embedding medium for histological analysis of 3D porous scaffold material.
abstract: When sectioning a 3D porous scaffold made of a soft elastomeric material embedded in paraffin medium, it is not easy to obtain a section because of the different mechanical properties of the paraffin and tissue/scaffold. We describe a new embedding material for histological analysis of various biomaterials that is composed of paraffin and ethylene vinyl acetate (EVA) resin (0, 3, 7, and 13 wt.%). 3D porous poly(L-lactide-epsilon-caprolactone) (PLCL) and chitosan scaffolds were fabricated to test the sectioning efficiency of the paraffin/EVA embedding material. The new embedding material was characterized by rheological analysis and solvent solubility testing in xylene and n-hexane. The hydrophilicity of the new material was assessed by contact angle measurement and its surface roughness was measured using AFM analysis. The staining efficiency of sections embedded in a paraffin/EVA mixture was determined by eosin staining of the chitosan scaffold and chitosan/collagen hybrid scaffold using a fluorescently labeled collagen. Section roughness decreased with increasing EVA content. The softening temperature of the paraffin/EVA mixture was similar to that of paraffin (50-60 degrees C by rheometer). The paraffin/EVA mixture dissolved completely in xylene after 30min at 50 degrees C, and after 30min in n-hexane at 60 degrees C. Therefore, the new embedding medium can be used for histological analysis of various biomaterials and natural tissues.
authors.affiliation: Department of Dental Biomaterials Science, Dental Research Institute and BK21 Program, School of Dentistry, Seoul National University, Seoul, Republic of Korea.
authors.forename: Jin Ik
authors.initials: JI
authors.lastname: Lim
authors.forename: Yong-Keun
authors.initials: YK
authors.lastname: Lee
mesh_terms: D048271:Chitosan; D008422:Materials Testing; D010232:Paraffin / Q000737:chemistry; D011091:Polyesters; D011145:Polyvinyls / Q000737:chemistry*; D016062:Porosity; D013194:Staining and Labeling; D013499:Surface Properties; D013696:Temperature; D016610:Tissue Embedding / Q000379:methods*; D023822:Tissue Engineering / Q000295:instrumentation; D054457:Tissue Scaffolds
chemical_list: D011091:Polyesters; D011145:Polyvinyls; C016438:ethylenevinylacetate copolymer; C062968:lactide-caprolactone copolymer; D010232:Paraffin; D048271:Chitosan