title: Near-Infrared Spectroscopy Predicts Compositional and Mechanical Properties of Hyaluronic Acid-Based Engineered Cartilage Constructs.
abstract: Hyaluronic acid (HA) has been widely used for cartilage tissue engineering applications. However, the optimal time point to harvest HA-based engineered constructs for cartilage repair is still under investigation. In this study, we investigated the ability of a nondestructive modality, near-infrared spectroscopic (NIR) analysis, to predict compositional and mechanical properties of HA-based engineered cartilage constructs. NIR spectral data were collected from control, unseeded constructs, and twice per week by fiber optic from constructs seeded with chondrocytes during their development over an 8-week period. Constructs were harvested at 2, 4, 6, and 8 weeks, collagen and sulfated glycosaminoglycan content measured using biochemical assays, and the mechanical properties of the constructs evaluated using unconfined compression tests. NIR absorbances associated with the scaffold material, water, and engineered cartilage matrix, were identified. The NIR-determined matrix absorbance plateaued after 4 weeks of culture, which was in agreement with the biochemical assay results. Similarly, the mechanical properties of the constructs also plateaued at 4 weeks. A multivariate partial least square model based on NIR spectral input was developed to predict the moduli of the constructs, which resulted in a prediction error of 10% and R value of 0.88 for predicted versus actual values of dynamic modulus. Furthermore, the maximum increase in moduli was calculated from the first derivative of the curve fit of NIR-predicted and actual moduli values over time, and both occurred at ∼2 weeks. Collectively, these data suggest that NIR spectral data analysis could be an alternative to destructive biochemical and mechanical methods for evaluation of HA-based engineered cartilage construct properties.
authors.affiliation: 1 Tissue Imaging and Spectroscopy Lab, Department of Bioengineering, Temple University , Philadelphia, Pennsylvania.
authors.forename: Farzad
authors.initials: F
authors.lastname: Yousefi
authors.affiliation: 2 Department of Orthopaedic Surgery, University of Pennsylvania , Philadelphia, Pennsylvania.|3 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania.
authors.forename: Minwook
authors.initials: M
authors.lastname: Kim
authors.affiliation: 1 Tissue Imaging and Spectroscopy Lab, Department of Bioengineering, Temple University , Philadelphia, Pennsylvania.
authors.forename: Syeda Yusra
authors.initials: SY
authors.lastname: Nahri
authors.affiliation: 2 Department of Orthopaedic Surgery, University of Pennsylvania , Philadelphia, Pennsylvania.|3 Department of Bioengineering, University of Pennsylvania , Philadelphia, Pennsylvania.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Mauck
authors.affiliation: 1 Tissue Imaging and Spectroscopy Lab, Department of Bioengineering, Temple University , Philadelphia, Pennsylvania.
authors.forename: Nancy
authors.initials: N
authors.lastname: Pleshko
mesh_terms: D000818:Animals; D002356:Cartilage / Q000737:chemistry*; D002417:Cattle; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology*; D003094:Collagen / Q000737:chemistry; D006025:Glycosaminoglycans / Q000737:chemistry; D006820:Hyaluronic Acid / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry; D019265:Spectroscopy, Near-Infrared; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D006025:Glycosaminoglycans; D020100:Hydrogels; C013786:A73025; D006820:Hyaluronic Acid; D003094:Collagen
keywords: cartilage tissue engineering; hyaluronic acid; multivariate data analysis; near-infrared spectroscopy; nondestructive modality