Rapid Production of Highly Interconnected Porous Scaffolds by Spheroidized Sugar Particles for Tissue Engineering

Abstract

Irregular pore morphology has a significant influence on cell response and the control of pore interconnectivity in the scaffolds constructed for tissue engineering of bone. In this study, we explored a new porogen for particulate leaching technique to fabricate highly interconnected porous scaffold with pores in regular shape. A polymeric blend composed of poly-L-lactide PLLA and poly-e-caprolactone PCL with average molecular weights of 220 kDa and 50 kDa, respectively was used for the construction of the scaffold. Spheroidized sugar particles were produced by using a flame treatment with a Meker burner. This method enabled the formation of homogenous and symmetrical particles with high water solubility. A pigment was blended into this polymeric mixture to investigate the morphology by confocal microscopy. The fabricated scaffolds were thoroughly characterised physically and biologically. Porosity and average pore size values were calculated by m-CT as 83% and 312 mm respectively. Live/ dead assay by confocal microscopy demonstrated high cell attachment and cell viability in the scaffolds. This new scaffold fabrication method will be useful for tissue engineering community in the control of scaffold architecture.

Keywords

• Porous scaffolds,interconnectivity,spheroidized sugar particles,tissue engineering

Doku Mühendisliği İçin Küreselleştirilmiş Şeker Partikülleriyle Yüksek Gözenek Bağlantılarına Sahip Doku İskelelerinin Hızlı Üretimi

Abstract

Düzensiz gözenek morfolojisi kemik doku mühendisliği için tasarlanan doku iskelelerinde hücre cevabı ve gözenekler arası bağlantılar üzerinde önemli bir etkiye sahiptir. Bu çalışmada, oldukça yüksek gözenek bağlantıları olan doku iskelelerinin üretiminde partikül ekstraksiyonu yöntemi için yeni bir gözenek oluşturucu üretildi. Doku iskelelerinin oluşturulmasında poli-L-laktik asit PLLA ve poli-e-kaprolaktondan PCL ağırlıkça ortalama molekül ağırlıkları sırasıyla 220 kDa ve 50 kDa oluşan bir polimerik karışım kullanıldı. Bir Meker beki yardımıyla alev ile küreselleştirilmiş şeker partikülleri hazırlandı. Bu yöntemle suda oldukça iyi çözünerek uzaklaştırılabilen homojen ve simetrik partiküllerin oluşturulması mümkün oldu. Oluşturulan doku iskelelerinin gözenek morfolojisinin konfokal mikroskop altında incelenmesi için polimerik karışıma üretim sırasında bir pigment ilave edildi. Üretilen doku iskeleleri fiziksel ve biyolojik olarak karakterize edildi. Gözeneklilik ve ortalama gözenek boyu değerleri mikro-bilgisayarlı tomografi mikro-CT ile sırasıyla %83 ve 312 mm olarak belirlendi. Hücre kültürü neticesinde konfokal mikroskop ile canlı/cansız kiti uygulamasının sonuçları, doku iskelelerinde yüksek derecede hücre tutunması ve hücre canlılığına işaret etti. Bu yeni yöntemin doku iskelelerinin yapısal kontrolünde doku mühendisliği çalışan gruplar için oldukça yararlı olacağı düşünülmektedir

Keywords

• Gözenekli doku iskeleleri,birbirine bağlı gözenekler,küreselleştirilmiş şeker partikülleri,doku mühendisliği

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