Study on the drug release property of cholesteryl end‐functionalized poly(ε‐caprolactone) microspheres

Abstract

End-functionalized poly/oligo(epsilon-caprolactone)s were synthesized through the ring-opening polymerization of epsilon-caprolactone initiated by cholesterol with a hydroxyl group. Using the end-functionalized poly/oligo(epsilon-caprolactone)s with different molecular weights, the microsphere drug delivery systems were fabricated using a convenient melting-emulsion method. The drug release properties of microspheres were investigated with the presence of an enzyme, Pseudomonas cepacia lipase, as well as in the absence of the enzyme. The release profiles can be fitted nicely by the classical empirical exponential expression. Under the hydrolytic condition, the drug release is mainly controlled by Fickian diffusion, and the high molecular weight of the matrix results in a slower drug release rate. Under the enzymatic condition, the drug release is dominated by combined degradation and diffusion mechanism, and the high molecular weight sample exhibits a faster release rate that is mainly caused by the higher degradation rate of the sample with lower cholesteryl moiety content.

Synthesis of novel cholic acid functionalized branched oligo/poly(ε‐caprolactone)s for biomedical applications

“…Although the M w may affect the hydrolytic degradation rate, the main reasons of the accelerated degradation rate are the incorporation of the cholic acid moiety and the branched structure because our studies on other functionlized oligo/poly(e-caprolactone)s demonstrate that other linear oligomers/polymers with the similar M w values do not show obvious hydrolytic degradation after the same time period. 17 As we know, the slow degradation rate has considerably limited medical applications of PCL, our study provides a convenient and effective approach to adjust the degradation rate of PCL.…”

Synthesis and characterization of functionalized triblock polymer: The prepared polymer is cholesteryl terminated and chain‐extended PCL

“…For aliphatic cyclic esters, their ringopening polymerizations can be carried out in the presence of initiators bearing hydroxyl groups. [15][16][17][18][19] In this investigation, Chol-(CL) n -Chol triblock polymer was synthesized by two steps. As shown in Scheme 1, first, the Chol-(CL) m was synthesized by ring opening polymerization of e-caprolactone (e-CL) onto the Chol in the presence of stannous octoate as a catalyst.…”

“…12,13 Cholesterol (chol) moiety has been often chosen among them because of its high thermodynamic affinity for the cell membrane and its ability to change the membrane's permeability and fluidity. [14][15][16][17][18][19] Stupp and coworkers 15,16 reported that cholesteryl-oligo(L-lactic acid) obviously promoted cell adhesion and proliferation compared with poly(L-lactic acid). Later, Chen and coworkers [17][18][19] described the use of cholesteryl endcapped polycarbonates and cholesteryl-PCL as drug release carrier.…”

“…[14][15][16][17][18][19] Stupp and coworkers 15,16 reported that cholesteryl-oligo(L-lactic acid) obviously promoted cell adhesion and proliferation compared with poly(L-lactic acid). Later, Chen and coworkers [17][18][19] described the use of cholesteryl endcapped polycarbonates and cholesteryl-PCL as drug release carrier. These successful results clearly illustrate that functionalization of polyesters by cholesteryl moiety hold promise as scaffold materials for drug release and tissue engineering.…”

Synthesis and phase behaviour of new biodegradable liquid crystalline polycarbonate derived from side chain cholesteryl derivative

“…[31][32][33][34][35][36] Besides, LC materials containing cholesteryl groups have especially attracted more and more attention in the biomaterials fields. [3,[21][22][23][24][37][38][39][40][41] Stupp et al first reported the synthesis of cholesterol end functionalised oligo(L-lactic acid) and their interactions with cells. [21] Furthermore, Cheng [22] and Yang et al [23] also reported cholestery endcapped aliphatic polycarbonates and dicholestery end functionalised triblock poly(ε-caprolactone), respectively, as biodegradable polymers.…”