Name: composite scaffolds of interfacial polyelectrolyte fibers for temporally controlled release of biomolecules
Uploaded: 2015-08-19T14:00:00.000+00:00
Duration: 11 min 13 s
Description: Watch this Scientific Journal Video about Composite Scaffolds of Interfacial Polyelectrolyte Fibers for Temporally Controlled Release of Biomolecules at JoVE.com

이 작품은 우수 연구 센터, 제어 공학 연구소, 싱가포르 중 하나에 의해 관리되는 싱가포르 국립 연구 재단에 의해 지원되었다. MFAC는 1122703037. BKKT는 제어 공학 연구소 지원 연구를위한 과학, 기술 및 연구 기관 (싱가포르) 및 국가 기관 (프랑스) 프로젝트 번호에 따라 공동 프로그램에 의해 지원됩니다. 우리는 증명 판독 비디오 제작에 협조 원고와 양 새벽 JH 네오 씨 다니엘 HC 웡 감사합니다.

고분자 전해질 솔루션 1. 준비 <ol><li> 리아 외에서 설명하는대로, 키토산을 정제. 간략하게, 1 %를 만드는 2 % 키토산 용액 (/ V W) (v / v) 아세트산 함유하고, 진공 필터 (93)가 급 여과지. pH가 10 분 동안 1,200 XG에서 7 원심 침전 된 키토산에 안정화 될 때까지 5M 수산화 나트륨을 사용하여 여과 액을 중화. 뜨는을 가만히 따르다 및 키토산을 씻어 탈 이온수를 추가합니다. 원심 분리 및 세척 단계를 두 번 더 반복합니다. 정제 된 형태를 얻기 위해 -80 ° C 및 동결 건조 O / N에서 석출 키토산 동결. 제습 캐비닛에 정제 된 키토산을 저장합니다. </li><li> 무균 조직 배양 접시에 정제 키토산 1g을 달아. 생물학적 안전 캐비넷의 UV 램프에 최대한 가깝게 조직 배양 접시에 키토산을 넣고 15 분 동안 UV 광에 노출. 무균 핀셋을 사용하여, 유리 용기에 멸균 키토산 놓는다. 용해 키토산은 0 필터링 사용.0.5 %와 1 % 사이의 최종 농도 15M 아세트산 (W / V). </li><li> 알긴산 나트륨 0.1 g을 칭량하고 (w / v)의 용액을 1 %를 얻기 위해 탈 (DDI)의 증류수 10ml에 녹인다. 완전한 용해를 보장하기 위해 볼텍스 혼합기에서 적어도 2 시간 동안 알긴산 나트륨 염을 섞는다. 0.2 μm의 주사기 필터를 통해 알지네이트 용액 필터. 4 ° C에서 알지네이트 솔루션을 저장합니다. </li><li> 제조자가 권장하는 신경 성장 인자 (NGF), - 혈관 내피 성장 인자 (VEGF) 또는 베타 인간 재조합 성장 인자 재구성. </li></ol> IPC 섬유 2. 도면 <ol><li> 유사한 순 전하를 갖는 고분자 전해질 용액의 10 내지 20 μL의 분취 액으로 단백질, 성장 인자 또는 다른 생물 분자를 섞는다. 순 음전하 (예, 소 혈청 알부민 [BSA])와 생물학적 분자 알지네이트 용액을 혼합한다. 양전하 (예 : VEGF)와 생물 분자와 혼합되어야키토산 솔루션입니다. </li><li> 파라 필름으로 덮여 안정된 평평한 표면에 키토산 및 알긴산의 작은 분취 량 (10 ~ 20 μL)를 놓습니다. 키토산 및 알긴산 액 근접 배치 아니라 서로 접촉한다. </li><li> 가볍게 키토산과 알긴산 방울에 집게 한 쌍의 각 끝을 찍어. 함께 집게 곤란하여 고분자 전해질의 방울을 가져와. 물방울이 서로 접촉 할 때, 서서히 두 방울 (도 1a)의 인터페이스에서 IPC 섬유 그릴 수직 상방 집게를 당긴다. </li><li> 이러한주의 깊게 회전 맨드릴 상에 부착되어 플랫 고분자 담체로 집 전체에 겸자에 그려진 IPC 섬유의 단부를 배치했다 (제 3 및 4 참조). 유니폼과 IPC 섬유 beadless 형성 할 수 있도록 10mm / sec의 고정 된 속도로 맨드릴을 돌립니다. Incorporated의 버스트 방출을 일으킬 것이다 비드를 형성 할 것이다 IPC 섬유 드로잉 속도를 증가생화학 및 조기 섬유 종료. (10) </li><li> 통합의 효율성을 결정하기 위해, 남아있는 모든 액체가 1X 인산염 완충 생리 식염수 500 μL (PBS)으로 희석하여 파라 필름에 남아 수집합니다. BCA의 (BSA에 대한) 분석 (VEGF 및 NGF의 경우) 또는 ELISA 혼입 생체 분자를 검출하기 위해 적절한 분석을 통해 잔사 중의 단백질 또는 성장 인자의 함유량을 측정한다. </li></ol> 복합 하이드로 겔 풀루 란 - 덱스 트란의 비계 (PD) 다당류 및 IPC 섬유 3. 제작 <ol><li> IPC 섬유 수집을 위해 희생 풀루 란 프레임 제조 <ol><li> 풀루 란 다당류를 달아 (W / V) 수용액을 20 %를 만드는 증류 탈 (DDI) 물과 혼합. 균일 성을 보장하기 위해 풀루 란 솔루션 O / N을 섞는다. </li><li> 10cm 직경의 조직 문화 폴리스티렌 (FPC 기판) 접시에 풀루 란 용액 15g 캐스트. 37 ° C에서 풀루 란 솔루션 O / N을 건조. 7에 풀루 란 영화를 잘라MM은 7mm 사각 프레임을 X. </li></ol></li><li> 풀루 덱스 트란 폴리 사카 라이드 용액을 제조 <ol><li> 30 %를 만들기 다당류의 솔루션 풀루 란과 덱스 트란 (/ V W) : DDI 물 (3 1 비율). 폴리 사카 라이드 용액의 균질성을 확인하기 위해 O / N 섞는다. 천천히 20 %의 최종 농도를 달성하기 위해 다당류 용액에 중탄산 나트륨으로 추가 (W / V). 용액의 균일 성을 보장하기 위해 O / N을 섞는다. 4 ° C에서 다당류 솔루션을 저장합니다. </li></ol></li><li> 풀루 란 프레임 IPC 섬유를 수집 <ol><li> 악어 클립을 사용하여 희생 풀루 란 프레임 (3.1)를 붙입니다. 플라스틱 코팅 된 접착 테이프를 사용하여 회전 맨드릴의 끝에 악어 클립 및 풀루 란 프레임을 스틱. 10mm / sec의 일정한 속도로 부착 된 프레임 맨드릴을 돌립니다. 풀루 프레임은 원하는 방향으로 회전 맨드릴 상에 부착 될 수있다. </li></ol></li><li> 집게 쌍 (1 절)와 ATTAC을 사용하여 IPC 섬유 그리기H 회전 풀루 란 프레임 상에 IPC 섬유의 그린 끝. 일정 속도로 IPC 섬유를 그린다. IPC 섬유의 말단부에 도달 한 후, RT에서 N / 섬유 - 온 - 프레임 구조의 O를 건조. </li><li> PD 하이드로 겔 지지체에 IPC 섬유의 포함 </li><li> . (/ V W) 나트륨 수용액 및 100 μL의 10M 수산화 나트륨을 트리 메타 11 %, 100 ㎕를 추가 풀루 덱스 트란 용액의 각 그램 가교 7 1 ~ 2 분 동안 stirplate를 이용하여 60 rpm으로 용액을 혼합하기. 트리 메타 포스페이트 나트륨과 수산화 나트륨을 첨가 한 후, 폴리 사카 라이드 용액을 거의 즉시 가교 것이다. IPC 섬유를 완전히를 포함하는 섬유 - 온 - 프레임 구조에 점성 다당류 용액을 붓고. 화학적으로 가교 결합 된 복합체 지지체 (도 1b)를 형성하기 위해 30 분 동안 60 ° C에 결합 된 덱스 트란, 풀루 란 - IPC 섬유 (PD-IPC)를 부화. </li><li> 주의 : 흄 후드 단계 3.3.2을 수행하고 적절한 보호 동등를 사용아세트산 등의 pment 부식성 및 인화성이다. </li><li> PD-IPC 지지체의 기공 형성을 유도하기 위하여, 20 분에 20 % (w / v)의 아세트산 전체 골격 잠수함. </li><li> 100 rpm으로 흔들어 섞으면 서 5 분간 1X PBS에 세척 PD-IPC 골격에 의해 미 반응 시약을 제거합니다. 이 단계를 2 번 반복합니다. </li><li> 초과 PBS를 제거하고 즉시 -80 ° CO / N의 PD-IPC 발판을 동결. 비계 어떤 제어 방출 또는 생체 활성 분석에 사용하기 전에 적어도 24 시간을 동결 건조. </li></ol> PCL 및 IPC 섬유의 복합 비계 4. 제작 주의 : 디클로로 메탄은 위험한 물질이다. 디클로로 메탄을 처리 할 때 흄 후드 및 개인 보호 장비를 사용합니다. <ol><li> 깨끗한과 패턴 PDMS 기판 만들기 <ol><li> 소프트 리소그래피 공정을 이용하여 원하는 치수의 FPC 기판의 일부를 사용하여 깨끗한 폴리 디메틸 실록산 (PDMS) 탄성 기판 만든다. patte 만들기원하는 템플릿 지형 폴리 (메틸 메타 크릴 레이트)에 표준 소프트 리소그래피 방법을 사용하여 rned PDMS 기판. (12) </li></ol></li><li> IPC 섬유 수집을 위해 희생 PCL 프레임 제조 <ol><li> PCL을 달아 (W / V) 솔루션을 0.9 %를 만들 디클로로 메탄에 용해. PDMS 기판의 모든 1cm 2 지역의 경우, 0.9 % PCL 용액 500 μl를 놓습니다. 완전히 흄 후드에서 증발 디클로로 메탄 용매를 모두 허용합니다. 원하는 두께로 필름을 두껍게 0.9 % PCL 주조의 과정을 반복합니다. PDMS 기판에서 건조 PCL 필름을 제거합니다. 적절한 크기의 구멍을 뚫는을 사용하여 PCL 프레임에 구멍을 만듭니다. (2) </li></ol></li><li> PCL 프레임 IPC 섬유를 수집 <ol><li> 악어 클립 (4.2.1)에서 구멍 희생 PCL 프레임을 부착합니다. 플라스틱 코팅 된 접착 테이프를 사용하여 회전 맨드릴에 악어 클립 스틱. PCL의 FRAM에 IPC 섬유의 그린 끝을 연결합니다10mm / 초 (제 2)의 일정 속도로 회전을 시작하기 전에 전자. IPC 섬유 드로잉 종료 후, 섬유에 프레임 구조의 O / N에서 4 ℃에서 건조. </li></ol></li><li> 섬유에 프레임이 패턴 PCL 기판으로 구성 퍼가기 <ol><li> 필요에 따라, 깨끗한 또는 패턴 PCL 기반을 만들기 위해 PDMS 기판에 0.9 % PCL 용액 500 μl를 삭제합니다. 원하는 두께와 발판을 얻었다 0.9 % PCL 용액 다층 캐스트. 완전히 흄 후드에서 증발 디클로로 메탄 용매를 모두 허용합니다. </li><li> PCL베이스의 상단에있는 섬유에 프레임 구조 (섹션 4.3.1)을 놓습니다. 원하는 두께를 얻기 위해 섬유의 프레임 구성을 여러 번에 0.9 % PCL 솔루션을 추가하고 완전히 PCL-IPC 복합 지지체 (그림 1C을) 제조, IPC 섬유를 포함. </li></ol></li></ol> 복합 IPC 공사장 공중 발판에서 생물학 작용제의 릴리스 5. 측정 <ol><li> 배치 합성 PD IPC-또는PCL-IPC 골격 및 독립 실행 형 IPC 섬유를 별도로 24 웰 플레이트에. </li><li> 발판을 담그고 독립형 IPC 섬유를 1X PBS 500 μL와 함께. 37 ° C에서 샘플을 품어. 다양한 시점 (릴리스 미디어)에서 PBS를 수집하고 1X PBS 500 μL로 교체합니다. </li><li> 통합 생체 분자 누적 방출 프로파일을 계산하는 BCA 분석 (BSA), ELISA (VEGF 및 NGF) 또는 다른 적절한 분석을 이용하여 분리 배지에서 단백질 또는 증식 인자의 양을 측정한다. </li></ol> 합성 IPC 공사장 공중 발판에서 세포의 6. 시드 출시 생물 제의 생체 활성 테스트하는 <ol><li> 적어도 20 분 동안 생물학적 안전 캐비넷에 UV 광을 사용하여 동결 건조 PD-IPC 또는 PCL-IPC 복합 지지체 멸균. </li><li> 200 ㎕의 성장 배지에 2 × 105 세포의 세포 현탁액을 수득 표준 세포 배양 기술을 사용한다. 복합체 지지체 상 농축 세포 현탁액을 시드. AfteR 20 분, 완전히 비계 잠수함하는 성장 미디어의 최고 최대 볼륨을 설정합니다. </li><li> 이러한하는, Alamar 블루 대사 활동 분석, PC12의 신경 돌기 가지 분석 또는 면역와 같은 표준 기술을 통해 세포 활성을 측정합니다. </li></ol>

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F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composite+pullulan-dextran+polysaccharide+scaffold+with+interfacial+polyelectrolyte+complexation+fibers:+A+platform+with+enhanced+cell+interaction+and+spatial+distribution.">Composite pullulan-dextran polysaccharide scaffold with interfacial polyelectrolyte complexation fibers: A platform with enhanced cell interaction and spatial distribution.</a> Acta Biomater. 10 (10), 4410-4418 (2014).</li><li>Yow, S. Z., Quek, C. H., Yim, E. K. F., Lim, C. T., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collagen-based+fibrous+scaffold+for+spatial+organization+of+encapsulated+and+seeded+human+mesenchymal+stem+cells.">Collagen-based fibrous scaffold for spatial organization of encapsulated and seeded human mesenchymal stem cells.</a> Biomaterials. 30 (6), 1133-1142 (2009).</li><li>Yim, E. K. F., Wan, A. C. A., Le Visage, C., Liao, I. C., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proliferation+and+differentiation+of+human+mesenchymal+stem+cell+encapsulated+in+polyelectrolyte+complexation+fibrous+scaffold.">Proliferation and differentiation of human mesenchymal stem cell encapsulated in polyelectrolyte complexation fibrous scaffold.</a> Biomaterials. 27 (36), 6111-6122 (2006).</li><li>Liao, I. C., Wan, A. C., Yim, E. K. F., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlled+release+from+fibers+of+polyelectrolyte+complexes.">Controlled release from fibers of polyelectrolyte complexes.</a> J. Control. Release. 104 (2), 347-358 (2005).</li><li>Wan, A. C. A., Liao, I. C., Yim, E. K. F., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+fiber+formation+by+interfacial+polyelectrolyte+complexation.">Mechanism of fiber formation by interfacial polyelectrolyte complexation.</a> Macromolecules. 37 (18), 7019-7025 (2004).</li><li>Yim, E. K. F., Reano, R., Pang, S., Yee, A., Chen, C., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanopattern-induced+changes+in+morphology+and+motility+of+smooth+muscle+cells.">Nanopattern-induced changes in morphology and motility of smooth muscle cells.</a> Biomaterials. 26 (26), 5405-5413 (2005).</li><li>Sun, H., Xu, F., Guo, D., Yu, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+and+evaluation+of+NGF-microsphere+conduits+for+regeneration+of+defective+nerves.">Preparation and evaluation of NGF-microsphere conduits for regeneration of defective nerves.</a> Neurol. Res. 34 (5), 491-497 (2012).</li><li>Sim&#243;n-Yarza, T., Formiga, F. R., Tamayo, E., Pelacho, B., Prosper, F., Blanco-Prieto, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=PEGylated-PLGA+microparticles+containing+VEGF+for+long+term+drug+delivery.">PEGylated-PLGA microparticles containing VEGF for long term drug delivery.</a> Int. J. Pharm. 440 (1), 13-18 (2013).</li><li>Patel, Z. S., Ueda, H., Yamamoto, M., Tabata, Y., Mikos, A. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+and+in+vivo+release+of+vascular+endothelial+growth+factor+from+gelatin+microparticles+and+biodegradable+composite+scaffolds.">In vitro and in vivo release of vascular endothelial growth factor from gelatin microparticles and biodegradable composite scaffolds.</a> Pharm. Res. 25 (10), 2370-2378 (2008).</li><li>Sun, H., Xu, F., Guo, D., Liu, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+evaluation+of+the+effects+of+various+additives+and+polymers+on+nerve+growth+factor+microspheres.">In vitro evaluation of the effects of various additives and polymers on nerve growth factor microspheres.</a> Drug Dev. Int. Pharm. 40 (4), 452-457 (2014).</li><li>Lee, P. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+drug+release+from+hydrogel+matrices.">Kinetics of drug release from hydrogel matrices.</a> J. Control. Release. 2, 277-288 (1985).</li><li>Cutiongco, M. F. A., Choo, R. K. T., Shen, N. J. X., Chua, B. M. X., Sju, E., Choo, A. W. L., Le Visage, C., Yim, E. K. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Composite+scaffold+of+poly(vinyl+alcohol)+and+interfacial+polyelectrolyte+complexation+fibers+for+controlled+biomolecule+delivery.">Composite scaffold of poly(vinyl alcohol) and interfacial polyelectrolyte complexation fibers for controlled biomolecule delivery.</a> Front. Bioeng. Biotechnol. 3 (3), 1-12 (2015).</li><li>Yow, S. Z., Lim, T. H., Yim, E. K. F., Lim, C. T., Leong, K. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+3D+Electroactive+Polypyrrole-Collagen+Fibrous+Scaffold+for+Tissue+Engineering.">A 3D Electroactive Polypyrrole-Collagen Fibrous Scaffold for Tissue Engineering.</a> Polymers. 3 (1), 527-544 (2011).</li><li>Leong, M. F., Toh, J. K. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterned+prevascularised+tissue+constructs+by+assembly+of+polyelectrolyte+hydrogel+fibres.">Patterned prevascularised tissue constructs by assembly of polyelectrolyte hydrogel fibres.</a> Nat. Commun. 4, 2353 (2013).</li><li>Di Benedetto, F., Biasco, A., Pisignano, D., Cingolani, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patterning+polyacrylamide+hydrogels+by+soft+lithography.">Patterning polyacrylamide hydrogels by soft lithography.</a> Nanotechnology. 16 (5), S165 (2005).</li><li>Revzin, A., Russell, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+of+poly(ethylene+glycol)+hydrogel+microstructures+using+photolithography.">Fabrication of poly(ethylene glycol) hydrogel microstructures using photolithography.</a> Langmuir. 17 (18), 5440-5447 (2001).</li><li>Yim, E. K. F., Liao, I. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+compatibility+of+interfacial+polyelectrolyte+complexation+fibrous+scaffold:+evaluation+of+blood+compatibility+and+biocompatibility.">Tissue compatibility of interfacial polyelectrolyte complexation fibrous scaffold: evaluation of blood compatibility and biocompatibility.</a> Tissue Eng. Part A. 13 (2), 423-433 (2007).</li><li>Chaouat, M., Le Visage, C., Autissier, A., Chaubet, F., Letourneur, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+evaluation+of+a+small-diameter+polysaccharide-based+arterial+graft+in+rats.">The evaluation of a small-diameter polysaccharide-based arterial graft in rats.</a> Biomaterials. 27, 5546-5553 (2006).</li><li>Eshraghi, S., Das, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+and+microstructural+properties+of+polycaprolactone+scaffolds+with+one-dimensional,+two+dimensional,+and+three-dimensional+orthogonally+oriented+porous+architectures+produced+by+selective+laser+sintering.">Mechanical and microstructural properties of polycaprolactone scaffolds with one-dimensional, two dimensional, and three-dimensional orthogonally oriented porous architectures produced by selective laser sintering.</a> Acta Biomater. 6, 2467-2476 (2010).</li></ol>

The authors have nothing to disclose.

IPC 섬유 개의 반대로 대전 된 고분자 전해질의 상호 작용에 의해 형성된다. 프로세스는 안정된 섬유 형성을위한 자기 조립 공정을 용이하게 고분자 전해질의 계면에서의 복잡한 추출을 이용한다. IPC 섬유 형성의 메카니즘은 유사 대전이 고분자 전해질 복합체 과정에서 혼입 될 수있는 생리 활성 물질로 첨가되도록. 10,11는 반대로, 반대로 대전 된 고분자 전해질로 생리 활성 물질의 첨가?...

The extracellular matrix has inherent biochemical and biophysical cues that direct cell behaviors. Mimicking this physiological three-dimensional (3D) microenvironment is a widely explored strategy for regenerative medicine and tissue engineering applications. For example, both naturally-derived and synthetic substrates have been modified with topographical cues as a means to mimic the biophysical cellular environment.1 For example, polycaprolactone (PCL) scaffolds can be easily patterned by casting on patterned PDMS substrates.2 However, most synthetic scaffolds inadequately recapitulate the controlled biochemical environment in vivo. Bulk or surface modification of synthetic materials only present biochemical cues for cell attachment but still lack temporal regulation of biochemical delivery.3 Thus, there is a need for optimal scaffolds that can mimic the temporally regulated biochemical delivery system of the extracellular matrix. 
Biochemical delivery systems such as microspheres are plagued by problems of loss of bioactivity and low incorporation efficiency due to the severity and complexity of multi-step synthesis process.4-6 Alternative methods that use a one-step fabrication and incorporation method were proven to have excellent potential to create a favorable biochemical microenvironment without the accompanying inefficiency in incorporation and loss of bioactivity. One viable solution is the use of interfacial polyelectrolyte complexation (IPC) fibers to deliver and protect biological agents. When two oppositely charged polyelectrolyte aqueous solutions are brought together, IPC fibers can be drawn out from the interface. Virtually any type of hydrophlic biomolecule in aqueous solution can be added into either the negatively- or positively-charged polyelectrolyte solution, thus facilitating the incorporation of useful biomolecules into the IPC fiber during the complexation process. Furthermore, this process only requires aqueous and ambient conditions, thereby decreasing the risk of loss of bioactivity. Using this method, active growth factors2,7 even cells8,9 have been successfully delivered. In addition, the simple method of forming IPC fibers allows molding into any shape or orientation. The stability of such fibers has been advantageous in its incorporation into both hydrophobic2 and hydrophilic polymers7 to create composite scaffolds. These composite scaffolds with IPC fibers are beneficial for creating a physiologically relevant biochemical environment while providing physical anchorage for cells. 
In this study, we show a method to incorporate IPC fibers into a hydrophilic and a hydrophobic scaffold with topography for controlled release of active biomolecules. As a proof-of-concept, we incorporate IPC fibers made from chitosan and alginate into the biocompatible, non-immunogenic and non-antigenic pullulan-dextran hydrophilic hydrogel or the biocompatible polycaprolactone hydrophobic scaffold.

<table><tbody><tr><td>Pullulan&amp;nbsp;</td><td>Hayashibara Inc Okayama Japan</td><td></td><td>Molecular weight (MW) 200 kDa. This material is pharmaceutical grade pullulan used to make pullulan frames and PD-IPC scaffolds.</td></tr><tr><td>Dextran</td><td>Sigma Aldrich</td><td>D1037</td><td>MW 500 kDa. This material is no longer being produced by Sigma Aldrich. Alternative suggested is catalog number 31392 (Sigma Aldrich). This material is used to make PD-IPC scaffolds.</td></tr><tr><td>Sodium Bicarbonate&amp;nbsp;</td><td>Sigma Aldrich</td><td>S5761</td><td>Sodium bicarbonate must be slowly added to the pullulan-dextran polysaccharide solution. Rapid addition of sodium bicarbonate will result in precipitation.&amp;nbsp;</td></tr><tr><td>Sodium Trimetaphosphate</td><td>Sigma Aldrich</td><td>T5508</td><td>This chemical is hygroscopic and must be stored in the dehumidifying cabinet. Aqueous solution of sodium trimetaphosphate must always be made fresh.</td></tr><tr><td>Sodium Hydroxide</td><td>Sigma Aldrich</td><td>S5881</td><td>This material is hazardous and must be handled with proper protective equipment such as nitrile gloves.</td></tr><tr><td>Chitosan</td><td>Sigma Aldrich</td><td>448877</td><td>MW 190-310 kDa. Acetylation degree of 75% to 85%. Purification of chitosan is required to create stable IPC fibers.</td></tr><tr><td>Acetic Acid</td><td>Merck</td><td></td><td>This can be replaced by another brand type. This material is corrosive and flammable. Protective equipment such as face shield, nitrile gloves, lab coat and shoe cover must be worn when handling this chemical in the fume hood.&amp;nbsp;</td></tr><tr><td>Alginic acid sodium salt from brown algae, low viscosity</td><td>Sigma Aldrich</td><td>A2158</td><td>Dissolve in water overnight. Filter through sterile 0.2&amp;nbsp;&amp;micro;m syringe filter before use. Store at 4 &amp;deg;C.</td></tr><tr><td>Bovine Serum Albumin</td><td>Sinopharm Chemical Reagent</td><td></td><td>Dissolve in sterile PBS and filter using 0.2 &amp;micro;m syringe filter before use.&amp;nbsp;</td></tr><tr><td>BCA assay kit</td><td>Pierce</td><td>23225</td><td>This kit was used to measure BSA release from PD-IPC scaffolds.&amp;nbsp;</td></tr><tr><td>Human Recombinant Vascular Endothelial Growth Factor</td><td>R&amp;amp;D systems</td><td>293-VE</td><td>Dissolve growth factor in 0.2% heparin solution to a final concentration of 5&amp;nbsp;mg/ml.</td></tr><tr><td>Heparin Sodium Salt From Porcine</td><td>Sigma Aldrich</td><td>H3393</td><td>This can be replaced by another brand type. Dissolve heparin salt in sterile water at a final concentration of 1% and filter through 0.2 &amp;micro;m syringe filter before use.&amp;nbsp;</td></tr><tr><td>Human Umbilical Vein Endothelial Cells (HUVEC)</td><td>Lonza</td><td>C2517A</td><td>This primary cell type was used in the assay to determine VEGF bioactivity after release from PD-IPC scaffolds.&amp;nbsp;</td></tr><tr><td>Alamar blue</td><td>Life Technologies</td><td>DAL1025</td><td>This is used to measure cell metabolic activity. Incubate Alamar blue with cells and maintain in standard cell culture conditions for 2 to 4 hours. Measure absorbance at 570 nm to determine Alamar blue percent reduction, which is correlated to the cell activity.&amp;nbsp;</td></tr><tr><td>ScanVac Coolsafe Lyophilizer</td><td>Labogene</td><td>7.001.200.060</td><td>This is a non-programmable freeze dryer that operates at -105 to -110&amp;nbsp;&amp;deg;C. This can be replaced by other standard lab lyophilizers.</td></tr><tr><td>Polycaprolactone (PCL)</td><td>Sigma Aldrich</td><td>181609</td><td>MW 65 kDa. This is no longer being manufactured by Sigma Aldrich. This can be replaced by Sigma Aldrich catalog number 704105.</td></tr><tr><td>Dichloromethane</td><td>Sigma Aldrich</td><td>V800151</td><td>This can be replaced by another brand type. This material is hazardous and must be handled in the fume hood. Protective equipment must be worn at all times when handling this chemical.</td></tr><tr><td>Polydimethylsiloxane (PDMS; 184 Silicone Elastomer Kit)</td><td>Dow Corning</td><td>(240)4019862</td><td>The elastomer kit comes with polymer base and crosslinker. Mixing the polymer base and crosslinker in different ratios will result in different stiffness of the PDMS.</td></tr><tr><td>Human Recombinant Beta-Nerve Growth Factor (NGF)</td><td>R&amp;amp;D systems</td><td>256-GF</td><td>Reconstituted in sterile DI water to a final concentration of 100&amp;nbsp;&amp;micro;g&amp;#8288;/&amp;#8288;ml. Aliquot and store in -20 &amp;deg;C until use.</td></tr><tr><td>Human Mesenchymal Stem Cells (hMSC)</td><td>Cambrex</td><td></td><td>This cell type was used in the assay to determine synergistic effect of NGF and nanotopography.</td></tr><tr><td>Rat PC12 Pheochromocytoma Cells&amp;nbsp;</td><td>ATCC</td><td></td><td>This cell type was used in the neurite outgrowth assay to determine bioactivity of NGF. After exposure to release media with NGF, measure number of cells with neurite extensions and normalize to total number of cells.</td></tr><tr><td>Grade 93 filter paper</td><td>Whatman</td><td>Z699675</td><td>This is used for the purification of chitosan after its precipitation with sodium hydroxide at pH&amp;nbsp;7.</td></tr><tr><td>Swing bucket centrifuge</td><td>Eppendorf</td><td>5810R</td><td>To be used during the purification of chitosan using 1,200 x g speed.</td></tr><tr><td>Motor with mandrel rotating at constant speed</td><td>Rhymebus</td><td>RM5E</td><td>The motor is used for the fabrication of IPC fibers on pullulan or PCL frame.</td></tr><tr><td>Phosphate buffered saline</td><td>FirstBase</td><td></td><td>Sterilize through filtration (0.2 &amp;micro;m filter) and autoclave.&amp;nbsp;</td></tr><tr><td>10-mm diameter Tissue Culture Polystyrene Dish (TCPS)</td><td>Greiner</td><td></td><td>The TCPS dish is used for casting of pullulan frame.&amp;nbsp;</td></tr><tr><td>Human VEGF ELISA kit</td><td>R&amp;amp;D systems</td><td>DVE00</td><td>The ELISA kit is used for detection of VEGF in the release medium.</td></tr><tr><td>Human NGF ELISA kit</td><td>R&amp;amp;D systems</td><td>DY256</td><td>The ELISA kit is used for detection of NGF in the release medium.</td></tr><tr><td>Plastic Coated Adhesive Tape</td><td>Bel-Art</td><td>9040336</td><td>The adhesive tape is used to securely stick the alligator clip to the rotating mandrel</td></tr></tbody></table>

composite scaffolds of interfacial polyelectrolyte fibers for temporally controlled release of biomolecules

Various scaffolds used in tissue engineering require a controlled biochemical environment to mimic the physiological cell niche. Interfacial polyelectrolyte complexation (IPC) fibers can be used for controlled delivery of various biological agents such as small molecule drugs, cells, proteins and growth factors. The simplicity of the methodology in making IPC fibers gives flexibility in its application for controlled biomolecule delivery. Here, we describe a method of incorporating IPC fibers into two different polymeric scaffolds, hydrophilic polysaccharide and hydrophobic polycaprolactone, to create a multi-component composite scaffold. We showed that IPC fibers can be easily embedded into these polymeric structures, enhancing the capability for sustained release and improved preservation of biomolecules. We also created a composite polymeric scaffold with topographical cues and sustained biochemical release that can have synergistic effects on cell behavior. Composite polymeric scaffolds with IPC fibers represent a novel and simple method of recreating the cellular niche.

이 글에서, 우리는 다양한 생체 분자의 서방에 대한 IPC 섬유와 복합 발판을 만드는 노력했다. 본 연구에서 사용 된 생체 분자의 특성을 표 1에서 발견된다. IPC 섬유는 제 PD-IPC 복합체 지지체 (도 1B)를 만들기 위해 PD 친수성 하이드로 겔에 포함 하였다. 모델 분자 BSA 먼저 제어 생체 릴리스 복합체 지지체를 사용하는 타당성을 결정하기 위하여 시험 하였다. BSA는 45 ± 0.97 %의...

Watch this Scientific Journal Video about Composite Scaffolds of Interfacial Polyelectrolyte Fibers for Temporally Controlled Release of Biomolecules at JoVE.com

Composite Scaffolds of Interfacial Polyelectrolyte Fibers for Temporally Controlled Release of Biomolecules

Scaffolds for tissue engineering need to recapitulate the complex biochemical and biophysical microenvironment of the cellular niche. Here, we show the use of interfacial polyelectrolyte complexation fibers as a platform to create composite, multi-component polymeric scaffolds with sustained biochemical release.

생체 분자 시간적으로 방출 제어용 고분자 전해질 계면 섬유의 복합 공사장 공중 발판

Various scaffolds used in tissue engineering require a controlled biochemical environment to mimic the physiological cell niche. Interfacial ...

composite-scaffolds-interfacial-polyelectrolyte-fibers-for-temporally

Research

JoVE Journal

Bioengineering

8.3K 조회수.  National University of Singapore. Scaffolds for tissue engineering need to recapitulate the complex biochemical and biophysical microenvironment of the cellular niche. Here, we show the use of interfacial polyelectrolyte complexation fibers as a platform to create composite, multi-component polymeric scaffolds with sustained biochemical release.

비디오: Composite Scaffolds of Interfacial Polyelectrolyte Fibers for Temporally Controlled Release of Biomolecules

Density Gradient Multilayered Polymerization (DGMP): A Novel Technique for Creating Multi-compartment, Customizable Scaffolds for Tissue Engineering

Complex tissue culture matrices, in which types and concentrations of biological stimuli (e.g. growth factors, inhibitors, or small molecules) or matrix structure (e.g. composition, concentration, or stiffness of the matrix) vary over space, would enable a wide range of investigations concerning how these variables affect cell differentiation, migration, and other phenomena. The major challenge in creating layered matrices is maintaining the structural integrity of layer interfaces without diffusion of individual components from each layer1. Current methodologies to achieve this include photopatterning2-3, lithography4, sequential functionalization5, freeze drying6, microfluidics7, or centrifugation8, many of which require sophisticated instrumentation and technical skills. Others rely on sequential attachment of individual layers, which may lead to delamination of layers9. 
DGMP overcomes these issues by using an inert density modifier such as iodixanol to create layers of varying densities10. Since the density modifier can be mixed with any prepolymer or bioactive molecule, DGMP allows each scaffold layer to be customized. Simply varying the concentration of the density modifier prevents mixing of adjacent layers while they remain aqueous. Subsequent single step polymerization gives rise to a structurally continuous multilayered scaffold, in which each layer has distinct chemical and mechanical properties. The density modifier can be easily removed with sufficient rinsing without perturbation of the individual layers or their components. This technique is therefore well suited for creating hydrogels of various sizes, shapes, and materials.
A protocol for fabricating a 2D-polyethylene glycol (PEG) gel, in which alternating layers incorporate RGDS-350, is outlined below. We use PEG because it is biocompatible and inert. RGDS, a cell adhesion peptide11, is used to demonstrate spatial restriction of a biological cue, and the conjugation of a fluorophore (Alexa Fluor 350) enables us to visually distinguish various layers. This procedure can be adapted for other materials (e.g. collagen, hyaluronan, etc.) and can be extended to fabricate 3D gels with some modifications10.

Density Gradient Multilayered Polymerization DGMP: A Novel Technique for Creating Multi-compartment, Customizable Scaffolds for Tissue Engineering

Here we describe a unique strategy for creating biocompatible, layered matrices with continuous interfaces between distinct layers for tissue engineering. Such a scaffold could provide an ideal customizable environment to modulate cell behavior by various biological, chemical or mechanical cues

밀도 그라데이션 Multilayered 중합 (DGMP) : 멀티 칸 만들기위한 소설 기법, 조직 공학을위한 사용자 정의 공사장 공중 발판

Complex tissue culture matrices, in which types and concentrations of biological stimuli (e.g. growth factors, inhibitors, or small molecules) or matrix ...

연구

생체공학

Expansion of Two-dimension Electrospun Nanofiber Mats into Three-dimension Scaffolds

Electrospinning has been the preferred technology in producing a synthetic, functional scaffold due to the biomimicry to extracellular matrix and the ease control of composition, structure, and diameter of fibers. However, despite these advantages, traditional electrospun nanofiber scaffolds come with limitations including disorganized nanofiber orientation, low porosity, small pore size, and mainly two-dimensional mats. As such, there is a great need for developing a new process for fabricating electrospun nanofiber scaffolds that can overcome the above limitations. Herein, a novel and simple method is outlined. A traditional 2D nanofiber mat is transformed into a 3D scaffold with desired thickness, gap distance, porosity, and nanotopographic cues to allow for cell seeding and proliferation through the depressurization of subcritical CO2 fluid. In addition to providing a scaffold for tissue regeneration to occur, this method also provides the opportunity to encapsulate bioactive molecules such as antimicrobial peptides for local drug delivery. The CO2 expanded nanofiber scaffolds hold great potential in tissue regeneration, wound healing, 3D tissue modeling, and topical drug delivery.

This article demonstrates the technique of expanding a traditional, two-dimension (2D) electrospun nanofiber mat into a three-dimension (3D) scaffold through the depressurization of subcritical CO2 fluid. These augmented scaffolds are 3D, closely mimic cellular nanotopographic cues, and preserve the functions of biologic molecules encapsulated within the nanofibers.

건설 기계 3-차원으로 2 차원 Electrospun Nanofiber 매트의 확장

Electrospinning has been the preferred technology in producing a synthetic, functional scaffold due to the biomimicry to extracellular matrix and the ease ...

유전학

Interview: Bioreactors and Surfaced-Modified 3D-Scaffolds for Stem Cell Research

A Nature Editorial in 2003 asked the question "Good-bye, flat biology?" What does this question imply? In the past, many in vitro culture systems, mainly monolayer cultures, often suffered from the disadvantage that differentiated primary cells had a relatively short life-span and de-differentiated during culture. As a consequence, most of their organ-specific functions were lost rapidly. Thus, in order to reproduce better conditions for these cells in vitro, modifications and adaptations have been made to conventional monolayer cultures.
The last generation of CellChips -- micro-thermoformed containers -- a specific technology was developed, which offers the additional possibility to modify the whole surface of the 3D formed containers. This allows a surface-patterning on a submicron scale with distinct signalling molecules. Sensors and signal electrodes may be incorporated. Applications range from basic research in cell biology to toxicology and pharmacology. Using biodegradable polymers, clinical applications become a possibility. Furthermore, the last generation of micro-thermoformed chips has been optimized to allow for cheap mass production.

In the past many in vitro culture systems -- mainly monolayer cultures -- often suffered from the disadvantage that differentiated primary cells had a relatively short life-span and de-differentiated during culture. As a consequence, most of their organ-specific functions were lost rapidly. Thus, in order to reproduce better conditions for these cells in vitro, modifications and adaptations have been made to conventional monolayer cultures.

인터뷰 : 줄기 세포 연구에 대한 Bioreactors와 분수 - 수정된 3D - 공사장 공중 발판

A Nature Editorial in 2003 asked the question  "Good-bye, flat biology?"  What does this question imply? In the past, many in vitro culture systems,  ...

생물학

Self-reporting Scaffolds for 3-Dimensional Cell Culture

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting 3D cellular construct can often be more relevant to studying the molecular events and cell-cell interactions than similar experiments studied in 2D. To create effective 3D cultures with high cell viability throughout the scaffold the culture conditions such as oxygen and pH need to be carefully controlled as gradients in analyte concentration can exist throughout the 3D construct. Here we describe the methods of preparing biocompatible pH responsive sol-gel nanosensors and their incorporation into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds along with their subsequent preparation for the culture of mammalian cells. The pH responsive scaffolds can be used as tools to determine microenvironmental pH within a 3D cellular construct. Furthermore, we detail the delivery of pH responsive nanosensors to the intracellular environment of mammalian cells whose growth was supported by electrospun PLGA scaffolds. The cytoplasmic location of the pH responsive nanosensors can be utilized to monitor intracellular pH (pHi) during ongoing experimentation.

Biocompatible pH responsive sol-gel nanosensors can be incorporated into poly(lactic-co-glycolic acid) (PLGA) electrospun scaffolds. The produced self-reporting scaffolds can be used for in&#160;situ monitoring of microenvironmental conditions whilst culturing cells upon the scaffold. This is beneficial as the 3D cellular construct can be monitored in real-time without disturbing the experiment.

3 차원 세포 배양을위한 자기보고 발판

Culturing cells in 3D on appropriate scaffolds is thought to better mimic the in vivo microenvironment and increase cell-cell interactions. The resulting ...

Fabrication of a Bioactive, PCL-based "Self-fitting" Shape Memory Polymer Scaffold

Tissue engineering has been explored as an alternative strategy for the treatment of critical-sized cranio-maxillofacial (CMF) bone defects. Essential to the success of this approach is a scaffold that is able to conformally fit within an irregular defect while also having the requisite biodegradability, pore interconnectivity and bioactivity. By nature of their shape recovery and fixity properties, shape memory polymer (SMP) scaffolds could achieve defect &#8220;self-fitting.&#8221; In this way, following exposure to warm saline (~60 &#186;C), the SMP scaffold would become malleable, permitting it to be hand-pressed into an irregular defect. Subsequent cooling (~37 &#186;C) would return the scaffold to its relatively rigid state within the defect. To meet these requirements, this protocol describes the preparation of SMP scaffolds prepared via the photochemical cure of biodegradable polycaprolactone diacrylate (PCL-DA) using a solvent-casting particulate-leaching (SCPL) method. A fused salt template is utilized to achieve pore interconnectivity. To realize bioactivity, a polydopamine coating is applied to the surface of the scaffold pore walls. Characterization of self-fitting and shape memory behaviors, pore interconnectivity and in vitro bioactivity are also described.

Scaffolds capable of fitting within cranio-maxillofacial (CMF) bone defects while exhibiting osteoconductivity and bioactivity are of interest. This protocol describes the preparation of a shape memory scaffold based on polycaprolactone diacrylate (PCL-DA) using a solvent-casting particulate-leaching (SCPL) method employing a fused salt template and application of a bioactive polydopamine coating.

생리 활성, PCL 기반 &quot;셀프 피팅&quot;형상 기억 폴리머 비계의 제작

Tissue engineering has been explored as an alternative strategy for the treatment of critical-sized cranio-maxillofacial (CMF) bone defects. Essential to ...

Three-dimensional Biomimetic Technology: Novel Biorubber Creates Defined Micro- and Macro-scale Architectures in Collagen Hydrogels

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper composition, targeted modulus, and well-defined architectural features. Biomaterials that recapitulate the intrinsic architecture of in vivo tissue are vital for studying diseases as well as to facilitate the regeneration of lost and malformed soft tissue. A novel biofabrication technique was developed which combines state of the art imaging, three-dimensional (3D) printing, and selective enzymatic activity to create a new generation of biomaterials for research and clinical application. The developed material, Bovine Serum Albumin rubber, is reaction injected into a mold that upholds specific geometrical features. This sacrificial material allows the adequate transfer of architectural features to a natural scaffold material. The prototype consists of a 3D collagen scaffold with 4 and 3 mm channels that represent a branched architecture. This paper emphasizes the use of this biofabrication technique for the generation of natural constructs. This protocol utilizes a computer-aided software (CAD) to manufacture a solid mold which will be reaction injected with BSA rubber followed by the enzymatic digestion of the rubber, leaving its architectural features within the scaffold material.

An innovative biofabrication technique was developed to engineer three-dimensional constructs that resemble the architectural features, components, and mechanical properties of in vivo tissue. This technique features a newly developed sacrificial material, BSA rubber, which transfers detailed spatial features, reproducing the in vivo architectures of a wide variety of tissues.

세 가지 차원 생체 모방 기술 ​​: 소설 Biorubber는 콜라겐 하이드로 겔에 마이크로 및 매크로 스케일 아키텍처를 정의 작성합니다

Tissue scaffolds play a crucial role in the tissue regeneration process. The ideal scaffold must fulfill several requirements such as having proper ...

A Facile and Eco-friendly Route to Fabricate Poly(Lactic Acid) Scaffolds with Graded Pore Size

Over the recent years, functionally graded scaffolds (FGS) gaineda crucial role for manufacturing of devices for tissue engineering. The importance of this new field of biomaterials research is due to the necessity to develop implants capable of mimicking the complex functionality of the various tissues, including a continuous change from one structure or composition to another. In this latter context, one topic of main interest concerns the design of appropriate scaffolds for bone-cartilage interface tissue. In this study, three-layered scaffolds with graded pore size were achieved by melt mixing poly(lactic acid) (PLA), sodium chloride (NaCl) and polyethylene glycol (PEG). Pore size distributions were controlled by NaCl granulometry and PEG solvation. Scaffolds were characterized from a morphological and mechanical point of view. A correlation between the preparation method, the pore architecture and compressive mechanical behavior was found. The interface adhesion strength was quantitatively evaluated by using a custom-designed interfacial strength test. Furthermore, in order to imitate the human physiology, mechanical tests were also performed in phosphate buffered saline (PBS) solution at 37 &#176;C. The method herein presented provides a high control of porosity, pore size distribution and mechanical performance, thus offering the possibility to fabricate three-layered scaffolds with tailored properties by following a simple and eco-friendly route.

A Facile and Eco-friendly Route to Fabricate PolyLactic Acid Scaffolds with Graded Pore Size

In this work, poly(lactic acid)/polyethylene glycol (PLA/PEG) scaffolds were prepared by using a combination of melt mixing and selective leaching. The method herein discussed permitted to develop three-layer scaffolds by highly controlling both porosity and pore size. The mechanical properties were also evaluated in a physiological environment.

손쉬운 및 환경 친화적 인 경로는 그레이드 기공 크기와 폴리 (젖산) 공사장 공중 발판을 제조

Over the recent years, functionally graded scaffolds (FGS) gaineda crucial role for manufacturing of devices for tissue engineering. The importance of ...

Fabrication of Extracellular Matrix-derived Foams and Microcarriers as Tissue-specific Cell Culture and Delivery Platforms

Cell function is mediated by interactions with the extracellular matrix (ECM), which has complex tissue-specific composition and architecture. The focus of this article is on the methods for fabricating ECM-derived porous foams and microcarriers for use as biologically-relevant substrates in advanced 3D in vitro cell culture models or as pro-regenerative scaffolds and cell delivery systems for tissue engineering and regenerative medicine. Using decellularized tissues or purified insoluble collagen as a starting material, the techniques can be applied to synthesize a broad array of tissue-specific bioscaffolds with customizable geometries. The approach involves mechanical processing and mild enzymatic digestion to yield an ECM suspension that is used to fabricate the three-dimensional foams or microcarriers through controlled freezing and lyophilization procedures. These pure ECM-derived scaffolds are highly porous, yet stable without the need for chemical crosslinking agents or other additives that may negatively impact cell function. The scaffold properties can be tuned to some extent by varying factors such as the ECM suspension concentration, mechanical processing methods, or synthesis conditions. In general, the scaffolds are robust and easy to handle, and can be processed as tissues for most standard biological assays, providing a versatile and user-friendly 3D cell culture platform that mimics the native ECM composition. Overall, these straightforward methods for fabricating customized ECM-derived foams and microcarriers may be of interest to both biologists and biomedical engineers as tissue-specific cell-instructive platforms for in vitro and in vivo applications.

The tissue-specific extracellular matrix (ECM) is a key mediator of cell function. This article describes methods for synthesizing pure ECM-derived foams and microcarriers that are stable in culture without the need for chemical crosslinking for applications in advanced 3D in vitro cell culture models or as pro-regenerative bioscaffolds.

조직 특이 적 세포 배양 및 전달 플랫폼과 같은 세포 외 기질 유래 거품과 마이크로 담체의 제조

Cell function is mediated by interactions with the extracellular matrix (ECM), which has complex tissue-specific composition and architecture. The focus ...

Core/shell Printing Scaffolds For Tissue Engineering Of Tubular Structures

Three-dimensional (3D) printing of core/shell filaments allows direct fabrication of channel structures with a stable shell that is cross-linked at the interface with a liquid core. The latter is removed post-printing, leaving behind a hollow tube. Integrating an additive manufacturing technique (like the one described here with tailor-made [bio]inks, which structurally and biochemically mimic the native extracellular matrix [ECM]) is an important step towards advanced tissue engineering. However, precise fabrication of well-defined structures requires tailored fabrication strategies optimized for the material in use. Therefore, it is sensible to begin with a set-up that is customizable, simple-to-use, and compatible with a broad spectrum of materials and applications. This work presents an easy-to-manufacture core/shell nozzle with luer-compatibility to explore core/shell printing of woodpile structures, tested with a well-defined, alginate-based scaffold material formulation.

Presented here is a simple-to-use, core/shell, three-dimensional bioprinting set-up for one-step fabrication of hollow scaffolds, suitable for tissue engineering of vascular and other tubular structures.

관 구조의 조직 공학을 위한 코어/쉘 인쇄 비계

Three-dimensional (3D) printing of core/shell filaments allows direct fabrication of channel structures with a stable shell that is cross-linked at the ...

Interlinked Macroporous 3D Scaffolds from Microgel Rods

A two-component system of functionalized microgels from microfluidics allows for fast interlinking into 3D macroporous constructs in aqueous solutions without further additives. Continuous photoinitiated on-chip gelation enables variation of the microgel aspect ratio, which determines the building block properties for the obtained constructs. Glycidyl methacrylate (GMA) or 2-aminoethyl methacrylate (AMA) monomers are copolymerized into the microgel network based on polyethylene glycol (PEG) star-polymers to achieve either epoxy or amine functionality. A focusing oil flow is introduced into the microfluidic outlet structure to ensure continuous collection of the functionalized microgel rods. Based on a recent publication, microgel rod-based constructs result in larger pores of several hundred micrometers and, at the same time, lead to overall higher scaffold stability in comparison to a spherical-based model. In this way, it is possible to produce higher-volume constructs with more free volume while reducing the amount of material required. The interlinked macroporous scaffolds can be picked up and transported without damage or disintegration. Amine and epoxy groups not involved in interlinking remain active and can be used independently for post-modification. This protocol describes an optimized method for the fabrication of microgel rods to form macroporous interlinked scaffolds that can be utilized for subsequent cell experiments.

Microgel rods with complementary reactive groups are produced via microfluidics with the ability to interlink in aqueous solution. The anisometric microgels jam and interlink into stable constructs with larger pores compared to spherical-based systems. Microgels modified with GRGDS-PC form macroporous 3D constructs that can be used for cell culture.

마이크로젤 로드의 상호 연결된 거대 다공성 3D 스캐폴드

A two-component system of functionalized microgels from microfluidics allows for fast interlinking into 3D macroporous constructs in aqueous solutions ...

생체 분자 시간적으로 방출 제어용 고분자 전해질 계면 섬유의 복합 공사장 공중 발판

요약

더 많은 비디오 탐색

이 비디오의 챕터

밀도 그라데이션 Multilayered 중합 (DGMP) : 멀티 칸 만들기위한 소설 기법, 조직 공학을위한 사용자 정의 공사장 공중 발판

건설 기계 3-차원으로 2 차원 Electrospun Nanofiber 매트의 확장

인터뷰 : 줄기 세포 연구에 대한 Bioreactors와 분수 - 수정된 3D - 공사장 공중 발판

3 차원 세포 배양을위한 자기보고 발판

생리 활성, PCL 기반 "셀프 피팅"형상 기억 폴리머 비계의 제작

세 가지 차원 생체 모방 기술 : 소설 Biorubber는 콜라겐 하이드로 겔에 마이크로 및 매크로 스케일 아키텍처를 정의 작성합니다

손쉬운 및 환경 친화적 인 경로는 그레이드 기공 크기와 폴리 (젖산) 공사장 공중 발판을 제조

조직 특이 적 세포 배양 및 전달 플랫폼과 같은 세포 외 기질 유래 거품과 마이크로 담체의 제조

관 구조의 조직 공학을 위한 코어/쉘 인쇄 비계

마이크로젤 로드의 상호 연결된 거대 다공성 3D 스캐폴드

생체 분자 시간적으로 방출 제어용 고분자 전해질 계면 섬유의 복합 공사장 공중 발판

요약

더 많은 비디오 탐색

이 비디오의 챕터

밀도 그라데이션 Multilayered 중합 (DGMP) : 멀티 칸 만들기위한 소설 기법, 조직 공학을위한 사용자 정의 공사장 공중 발판

건설 기계 3-차원으로 2 차원 Electrospun Nanofiber 매트의 확장

인터뷰 : 줄기 세포 연구에 대한 Bioreactors와 분수 - 수정된 3D - 공사장 공중 발판

3 차원 세포 배양을위한 자기보고 발판

생리 활성, PCL 기반 "셀프 피팅"형상 기억 폴리머 비계의 제작

세 가지 차원 생체 모방 기술 ​​: 소설 Biorubber는 콜라겐 하이드로 겔에 마이크로 및 매크로 스케일 아키텍처를 정의 작성합니다

손쉬운 및 환경 친화적 인 경로는 그레이드 기공 크기와 폴리 (젖산) 공사장 공중 발판을 제조

조직 특이 적 세포 배양 및 전달 플랫폼과 같은 세포 외 기질 유래 거품과 마이크로 담체의 제조

관 구조의 조직 공학을 위한 코어/쉘 인쇄 비계

마이크로젤 로드의 상호 연결된 거대 다공성 3D 스캐폴드

세 가지 차원 생체 모방 기술 : 소설 Biorubber는 콜라겐 하이드로 겔에 마이크로 및 매크로 스케일 아키텍처를 정의 작성합니다