PMID- 15544873
OWN - NLM
STAT- MEDLINE
DCOM- 20050321
LR  - 20181201
IS  - 0168-3659 (Print)
IS  - 0168-3659 (Linking)
VI  - 100
IP  - 2
DP  - 2004 Nov 24
TI  - Controlled release of hyaluronan oligomers from biodegradable polymeric 
      microparticle carriers.
PG  - 257-66
AB  - In the present study, biodegradable microparticles of blends of 
      poly(DL-lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) were 
      explored as a potential carrier for the controlled release of polysaccharide 
      oligomers. To this end, hyaluronan (HY) oligomers of varying molecular weights 
      were incorporated into PLGA/PEG microparticles. Using a two-level fractional 
      factorial experimental design, four microparticle formulation parameters, the 
      amount of PEG included in the microparticles, the initial HY loading of the 
      microparticles, the molecular weight of HY, and the molecular weight of PLGA, 
      were studied for their influence on the incorporation and in vitro release of HY 
      over the period of 28 days. The entrapment efficiencies were found to range 
      between 10+/-1% and 24+/-2% depending on the initial loading and the molecular 
      weight of the HY oligomer used in the fabrication of the microparticles. The HY 
      was released in a multiphasic fashion including an initial burst release, 
      followed by two separate periods of linear release. The normalized cumulative 
      mass released during the burst release ranged from 25.1+/-9.2% to 93.0+/-0.7% and 
      was found to be significantly influenced by the initial HY loading, the HY 
      molecular weight, and the PLGA molecular weight. The initial period of linear 
      release lasted from day 1 to day 14 and displayed normalized cumulative rates of 
      release from 0.1+/-0.0%/day to 1.4+/-0.2%/day. During this period, PEG content of 
      the microparticles and HY molecular weight exerted the greatest influence on the 
      rate of release. Finally, the second period of linear release lasted through the 
      final time-point at day 28. Here, the normalized cumulative rate of release 
      values ranged from 0.2+/-0.1%/day to 3.6+/-0.7%/day and were dependent on all 
      formulation parameters studied. These results demonstrate the potential of 
      PLGA/PEG blend microparticles for the controlled release of HY oligomers.
FAU - Hedberg, Elizabeth L
AU  - Hedberg EL
AD  - Department of Bioengineering, Rice University, P.O. Box 1892, MS-142, Houston, TX 
      77251-1892, USA.
FAU - Shih, Charles K
AU  - Shih CK
FAU - Solchaga, Luis A
AU  - Solchaga LA
FAU - Caplan, Arnold I
AU  - Caplan AI
FAU - Mikos, Antonios G
AU  - Mikos AG
LA  - eng
GR  - R01-AR48756/AR/NIAMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - Netherlands
TA  - J Control Release
JT  - Journal of controlled release : official journal of the Controlled Release 
      Society
JID - 8607908
RN  - 0 (Adjuvants, Immunologic)
RN  - 0 (Carbazoles)
RN  - 0 (Drug Carriers)
RN  - 0 (Excipients)
RN  - 0 (Polymers)
RN  - 0 (Solutions)
RN  - 0P2197HHHN (carbazole)
RN  - 1SIA8062RS (Polylactic Acid-Polyglycolic Acid Copolymer)
RN  - 26009-03-0 (Polyglycolic Acid)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 3WJQ0SDW1A (Polyethylene Glycols)
RN  - 9004-61-9 (Hyaluronic Acid)
SB  - IM
MH  - Adjuvants, Immunologic
MH  - Carbazoles/chemistry
MH  - Chemistry, Pharmaceutical
MH  - *Drug Carriers
MH  - Drug Compounding
MH  - Excipients
MH  - Hyaluronic Acid/*administration & dosage
MH  - Kinetics
MH  - Lactic Acid
MH  - Microspheres
MH  - Molecular Weight
MH  - Polyethylene Glycols
MH  - Polyglycolic Acid
MH  - Polylactic Acid-Polyglycolic Acid Copolymer
MH  - Polymers
MH  - Reference Standards
MH  - Solutions
EDAT- 2004/11/17 09:00
MHDA- 2005/03/22 09:00
CRDT- 2004/11/17 09:00
PHST- 2004/03/06 00:00 [received]
PHST- 2004/08/27 00:00 [accepted]
PHST- 2004/11/17 09:00 [pubmed]
PHST- 2005/03/22 09:00 [medline]
PHST- 2004/11/17 09:00 [entrez]
AID - S0168-3659(04)00401-8 [pii]
AID - 10.1016/j.jconrel.2004.08.020 [doi]
PST - ppublish
SO  - J Control Release. 2004 Nov 24;100(2):257-66. doi: 10.1016/j.jconrel.2004.08.020.