PMID- 9863528
OWN - NLM
STAT- MEDLINE
DCOM- 19990302
LR  - 20190815
IS  - 0142-9612 (Print)
IS  - 0142-9612 (Linking)
VI  - 19
IP  - 21
DP  - 1998 Nov
TI  - Manufacture of porous biodegradable polymer conduits by an extrusion process for 
      guided tissue regeneration.
PG  - 1945-55
AB  - We have fabricated porous, biodegradable tubular conduits for guided tissue 
      regeneration using a combined solvent casting and extrusion technique. The 
      biodegradable polymers used in this study were poly(DL-lactic-co-glycolic acid) 
      (PLGA) and poly(L-lactic acid) (PLLA). A polymer/salt composite was first 
      prepared by a solvent casting process. After drying, the composite was extruded 
      to form a tubular construct. The salt particles in the construct were then 
      leached out leaving a conduit with an open-pore structure. PLGA was studied as a 
      model polymer to analyze the effects of salt weight fraction, salt particle size, 
      and processing temperature on porosity and pore size of the extruded conduits. 
      The porosity and pore size were found to increase with increasing salt weight 
      fraction. Increasing the salt particle size increased the pore diameter but did 
      not affect the porosity. High extrusion temperatures decreased the pore diameter 
      without altering the porosity. Greater decrease in molecular weight was observed 
      for conduits manufactured at higher temperatures. The mechanical properties of 
      both PLGA and PLLA conduits were tested after degradation in vitro for up to 8 
      weeks. The modulus and failure strength of PLLA conduits were approximately 10 
      times higher than those of PLGA conduits. Failure strain was similar for both 
      conduits. After degradation for 8 weeks, the molecular weights of the PLGA and 
      PLLA conduits decreased to 38% and 43% of the initial values, respectively. 
      However, both conduits maintained their shape and did not collapse. The PLGA also 
      remained amorphous throughout the time course, while the crystallinity of PLLA 
      increased from 5.2% to 11.5%. The potential of seeding the conduits with cells 
      for transplantation or with biodegradable polymer microparticles for drug 
      delivery was also tested with dyed microspheres. These porous tubular structures 
      hold great promise for the regeneration of tissues which require tubular 
      scaffolds such as peripheral nerve, long bone, intestine, or blood vessel.
FAU - Widmer, M S
AU  - Widmer MS
AD  - Department of Chemical Engineering and Institute of Biosciences and 
      Bioengineering, Rice University, Houston, TX 77251-1892, USA.
FAU - Gupta, P K
AU  - Gupta PK
FAU - Lu, L
AU  - Lu L
FAU - Meszlenyi, R K
AU  - Meszlenyi RK
FAU - Evans, G R
AU  - Evans GR
FAU - Brandt, K
AU  - Brandt K
FAU - Savel, T
AU  - Savel T
FAU - Gurlek, A
AU  - Gurlek A
FAU - Patrick, C W Jr
AU  - Patrick CW Jr
FAU - Mikos, A G
AU  - Mikos AG
LA  - eng
GR  - R29-AR42639/AR/NIAMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - Biomaterials
JT  - Biomaterials
JID - 8100316
RN  - 0 (Biocompatible Materials)
RN  - 0 (Polyesters)
RN  - 0 (Polymers)
RN  - 1SIA8062RS (Polylactic Acid-Polyglycolic Acid Copolymer)
RN  - 26009-03-0 (Polyglycolic Acid)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 459TN2L5F5 (poly(lactide))
SB  - IM
MH  - Biocompatible Materials/*chemistry
MH  - Calorimetry, Differential Scanning
MH  - Chemical Phenomena
MH  - Chemistry, Physical
MH  - Guided Tissue Regeneration/instrumentation/*methods
MH  - Lactic Acid/*chemistry
MH  - Microscopy, Electron, Scanning
MH  - Particle Size
MH  - Polyesters
MH  - Polyglycolic Acid/*chemistry
MH  - Polylactic Acid-Polyglycolic Acid Copolymer
MH  - Polymers/*chemistry
MH  - Porosity
MH  - Temperature
OTO - NASA
OT  - NASA Discipline Cell Biology
OT  - Non-NASA Center
FIR - McIntire, L V
IR  - McIntire LV
IRAD- Rice U, Houston, TX
EDAT- 1998/12/24 03:03
MHDA- 2001/03/28 10:01
CRDT- 1998/12/24 03:03
PHST- 1998/12/24 03:03 [pubmed]
PHST- 2001/03/28 10:01 [medline]
PHST- 1998/12/24 03:03 [entrez]
AID - S0142-9612(98)00099-4 [pii]
AID - 10.1016/s0142-9612(98)00099-4 [doi]
PST - ppublish
SO  - Biomaterials. 1998 Nov;19(21):1945-55. doi: 10.1016/s0142-9612(98)00099-4.