Effect of Electrospun PLGA/Collagen Scaffolds on Cell Adhesion, Viability, and Collagen Release: Potential Applications in Tissue Engineering

1. Introduction

Tissue engineering is a multidisciplinary field that applies the principles of engineering and biology to develop biological substitutes that can be used in the reparation or regeneration of damaged tissue [1]. These substitutes are based on 3D polymeric scaffolds containing a porous and interconnected structure that can mimic the extracellular matrix (ECM) and act as temporal support for tissue regeneration [2]. In this sense, the scaffolds processing technique and the biomaterial used for its manufacture are crucial aspects to consider. Therefore, electrospinning is a simple and versatile technique to obtain scaffolds with fibrous 3D structure, high porous and pore interconnectivity, and high surface area morphology, similar to the ECM structure, allowing the transport of nutrients and regulating the signaling pathways responsible for cell absorption, proliferation, and differentiation [3].

On the other hand, an adequate strategy to develop scaffolds is combining a synthetic polymeric and a natural polymer, thus assuring a biomaterial with excellent mechanical properties, biodegradation, and biocompatibility [4]. Within the synthetic polymers used to obtain scaffolds, poly(lactic-co-glycolic acid) (PLGA) has great potential because it is a biodegradable and biocompatible polymer, is approved by the Food and Drug Administration (FDA) to be used in the human body, so it has been used in various biomedical applications as well as implants and controlled release of drugs [5]. In addition, the PLGA has the advantages of being easy to process, having excellent mechanical properties, and controlled degradation, which makes this polymer an alternative for regenerating tissue since this polymer can be biodegraded at the same time new tissue is being generated [6,7]. Although PLGA has been used as absorbable sutures, its degradation rate and compounds as lactic acid and glycolic acid can be customized to suit its application [8]. However, the hydrophobicity of PLGA and lack of cell affinity by the absence of surface cell recognition sites limits cell adhesion and, thus, its use as scaffolds in tissue engineering. Therefore, PLGA could be mixed with natural polymers such as collagen. Collagen is one protein found in different tissues currently, 20 families have been described, and the most abundant is type I collagen, which is present in bone tissue, skin, tendons, and ligaments [9]. Collagen has a complex hierarchical configuration that can be divided into a...