Imaging tissue engineering scaffolds using multiphoton microscopy

In this study, we combined two-photon autofluorescence and second harmonic generation imaging to investigate the three-dimensional microstructure and nonlinear optical properties of tissue engineering scaffolds. We focused on five different types of scaffold materials commonly used in tissue engineering, including: open-cell polylactic acid, polyglycolic acid, collagen composite scaffold, collagraft bone graft matrix strip, and nylon. By the use of multiphoton microscopy and a motorized stage, we obtained high resolution, spectrally resolved structural information of the scaffolds over large areas or in three-dimensions. Our results show that the nonlinear optical properties of the scaffolds will enable us to spectrally and morphologically distinguish the different types of scaffold materials investigated. We envision multiphoton microscopy to be a useful technique in tissue engineering applications in understanding the interplay between cultured cells and the scaffold materials.