Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling

Given the complexity of the nervous system, mechanisms to promote functional recovery at injury sites have yet been completely understood by both clinicians and researchers. Tissue engineering approaches serve as a potential therapy for neural regeneration. In particular, aligned sub-micron and nan-...

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Main Author: Chin, Jiah Shin
Other Authors: Chew Sing Yian
Format: Final Year Project (FYP)
Language:English
Published: 2016
Subjects:
Online Access:http://hdl.handle.net/10356/68407
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author Chin, Jiah Shin
author2 Chew Sing Yian
author_facet Chew Sing Yian
Chin, Jiah Shin
author_sort Chin, Jiah Shin
collection NTU
description Given the complexity of the nervous system, mechanisms to promote functional recovery at injury sites have yet been completely understood by both clinicians and researchers. Tissue engineering approaches serve as a potential therapy for neural regeneration. In particular, aligned sub-micron and nan-scale fibrous scaffolds which accurately mimic the topography of natural extracellular matrix can function as prospective scaffold candidates to facilitate recovery. In this study, a fiber fabrication technique, Electrospinning, was adopted and electrospun fibers were collected across an electrically charged air gap. Parameters were optimized to achieve aligned poly (Ɛ-caprolactone) (PCL) fiber with diameters ranging from 390nm to 1.14um. Though this fabrication technique has been proven efficient, the use of organic solvents, which are highly cytotoxic, to dissolve PCL is unfavorable for both in vitro and in vivo use. Hence, a solvent-free electrospinning technique, melt electrospinning, was established. Several configurations were explored and a stable heating system was obtained through a combination of proportional integral derivative (PID) controlling system coupled with the use of a solid state relay switching mechanism. This established setup was subsequently evaluated and proven to be feasible for melting low molecular weight PCL pallets to achieve a stable melt flow at high flow rates along with high heating temperature. Bio-functionality of aligned fibrous scaffolds can be established through incorporation of biochemical cue delivery. Gene silencing through RNA interference can be achieved with the use of small-interfering RNA (siRNA) and this technique has revealed immense potential in silencing inhibitory intrinsic factors of axonal regeneration at injury sites. Micellar Nanoparticles (MNP) has recently been developed and engaged in delivery of nucleic acids. Two copolymers, poly (Ɛ-caprolactone)-poly (ethylene glycol) (PCL-PEG) and poly (Ɛ-caprolactone)-poly (2-aminoethyl ethylene phosphate) (PCL-PPEEA), were used for MNP synthesis weight ratios of both copolymers were varied to obtain a range of MNPs exhibiting different particle sizes and charges. Upon siRNA loading, siRNA/MNP complexes were formed and these complexes had a general reduction in overall size as well as charge. Combination of MNPs with aligned fibrous scaffolds could serve as an efficient scaffold-mediated delivery system to induce functional recovery at injury sites especially within the non-permissive environment of the central nervous system (CNS).
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spelling ntu-10356/684072023-03-03T15:32:26Z Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling Chin, Jiah Shin Chew Sing Yian School of Chemical and Biomedical Engineering DRNTU::Engineering Given the complexity of the nervous system, mechanisms to promote functional recovery at injury sites have yet been completely understood by both clinicians and researchers. Tissue engineering approaches serve as a potential therapy for neural regeneration. In particular, aligned sub-micron and nan-scale fibrous scaffolds which accurately mimic the topography of natural extracellular matrix can function as prospective scaffold candidates to facilitate recovery. In this study, a fiber fabrication technique, Electrospinning, was adopted and electrospun fibers were collected across an electrically charged air gap. Parameters were optimized to achieve aligned poly (Ɛ-caprolactone) (PCL) fiber with diameters ranging from 390nm to 1.14um. Though this fabrication technique has been proven efficient, the use of organic solvents, which are highly cytotoxic, to dissolve PCL is unfavorable for both in vitro and in vivo use. Hence, a solvent-free electrospinning technique, melt electrospinning, was established. Several configurations were explored and a stable heating system was obtained through a combination of proportional integral derivative (PID) controlling system coupled with the use of a solid state relay switching mechanism. This established setup was subsequently evaluated and proven to be feasible for melting low molecular weight PCL pallets to achieve a stable melt flow at high flow rates along with high heating temperature. Bio-functionality of aligned fibrous scaffolds can be established through incorporation of biochemical cue delivery. Gene silencing through RNA interference can be achieved with the use of small-interfering RNA (siRNA) and this technique has revealed immense potential in silencing inhibitory intrinsic factors of axonal regeneration at injury sites. Micellar Nanoparticles (MNP) has recently been developed and engaged in delivery of nucleic acids. Two copolymers, poly (Ɛ-caprolactone)-poly (ethylene glycol) (PCL-PEG) and poly (Ɛ-caprolactone)-poly (2-aminoethyl ethylene phosphate) (PCL-PPEEA), were used for MNP synthesis weight ratios of both copolymers were varied to obtain a range of MNPs exhibiting different particle sizes and charges. Upon siRNA loading, siRNA/MNP complexes were formed and these complexes had a general reduction in overall size as well as charge. Combination of MNPs with aligned fibrous scaffolds could serve as an efficient scaffold-mediated delivery system to induce functional recovery at injury sites especially within the non-permissive environment of the central nervous system (CNS). Bachelor of Engineering (Chemical and Biomolecular Engineering) 2016-05-25T09:13:21Z 2016-05-25T09:13:21Z 2016 Final Year Project (FYP) http://hdl.handle.net/10356/68407 en Nanyang Technological University 119 p. application/pdf
spellingShingle DRNTU::Engineering
Chin, Jiah Shin
Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title_full Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title_fullStr Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title_full_unstemmed Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title_short Establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
title_sort establishing an aligned nanofibre platform to deliver synergistic topographical and biochemical signalling
topic DRNTU::Engineering
url http://hdl.handle.net/10356/68407
work_keys_str_mv AT chinjiahshin establishinganalignednanofibreplatformtodeliversynergistictopographicalandbiochemicalsignalling