Photocurable high internal phase emulsions (HIPEs) containing hydroxyapatite for additive manufacture of tissue engineering scaffolds with multi-scale porosity

Bone has a hierarchy of porosity that is often overlooked when creating tissue engineering scaffolds where pore sizes are typically confined to a single order of magnitude. High internal phase emulsion (HIPE) templating produces polymerized HIPEs (polyHIPEs): highly interconnected porous polymers which have two length scales of porosity covering the 1–100 µm range. However, additional larger scales of porosity cannot be introduced in the standard emulsion formulation. Researchers have previously overcome this by additively manufacturing emulsions; fabricating highly microporous struts into complex macroporous geometries. This is time consuming and expensive; therefore, here we assessed the feasibility of combining porogen leaching with emulsion templating to introduce additional macroporosity. Alginate beads between 275 and 780 µm were incorporated into the emulsion at 0, 50, and 100 wt%. Once polymerized, alginate was dissolved leaving highly porous polyHIPE scaffolds with added macroporosity. The compressive modulus of the scaffolds decreased as alginate porogen content increased. Cellular performance was assessed using MLO-A5 post-osteoblasts. Seeding efficiency was significantly higher and mineralized matrix deposition was more uniformly deposited throughout porogen leached scaffolds compared to plain polyHIPEs. Deep cell infiltration only occurred in porogen leached scaffolds as detected by histology and lightsheet microscopy. This study reveals a quick, low cost and simple method of producing multiscale porosity scaffolds for tissue engineering.

Download Full-text

Novel tissue engineering scaffolds as wound dressings loaded with Alkannins/Shikonins as active ingredients

10.1055/s-0039-3400068 ◽

2019 ◽

Author(s):

AS Arampatzis ◽

K Theodoridis ◽

E Aggelidou ◽

KN Kontogiannopoulos ◽

I Tsivintzelis ◽

...

Keyword(s):

Tissue Engineering ◽

Wound Dressings ◽

Active Ingredients ◽

Tissue Engineering Scaffolds

Download Full-text

HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

Dentika Dental Journal ◽

10.32734/dentika.v19i2.457 ◽

2016 ◽

Vol 19 (2) ◽

pp. 93-100

Author(s):

Lalita El Milla

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Functional Groups ◽

Bone Growth ◽

Three Dimensional ◽

Dimensional Structure ◽

Tissue Engineering Scaffolds ◽

Hydroxyapatite Powder ◽

Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

Download Full-text