Degradation and drug release property of star poly(ϵ‐caprolactone)s with dendritic cores

Abstract

A series of star poly(epsilon-caprolactone)s (PCL) with dendritic cores, PAMAM-PCLs, were synthesized through the ring-opening polymerization of epsilon-caprolactone (CL) initiated by poly(amidoamine) dendrimer (PAMAM-OH). By controlling the feed ratio of the macroinitiator PAMAM-OH to the monomer CL, the star polymers with different branch lengths and properties can be obtained. The successful incorporation of PCL sequences onto the PAMAM-OH core was verified by FTIR, 1H NMR, and combined size-exclusion chromatography and multiangle laser light scattering analysis. The in vitro degradation of PAMAM-PCLs was investigated. The results show the hydrolytic degradation rate increases with increasing content of hydrophilic PAMAM-OH core. While the enzymatic degradation rate is affected by two competitive factors, the catalytic effect of Pseudomonas cepacia lipase on the degradation of PCL branches and the hydrophilicity that depends on the polymer composition. Using the PAMAM-PCLs with different molecular weights, the microsphere drug delivery systems with submicron sizes were fabricated using an "ultrasonic assisted precipitation method." The in vitro drug release from these microspheres was investigated.

The Role of Lipase and α-Amylase in the Degradation of Starch/Poly(ɛ-Caprolactone) Fiber Meshes and the Osteogenic Differentiation of Cultured Marrow Stromal Cells

“…Several studies have reported the enzymatic degradation of PCL by lipase. [11][12][13][14]30 It is apparent from Figure 1 that the degradation of SPCL occurs in the presence of lipase, this enzyme being responsible for only 7.7 AE 1.6% weight loss after 30 days of immersion under dynamic conditions. These results are in accordance with several published studies.…”

“…Several studies have reported that lipase degrades PCL. [11][12][13][14] Lipases are watersoluble enzymes that hydrolyze ester bonds of watersoluble substrates such as triglycerides, phospholipids, and cholesteryl esters. 15,16 The lipase gene family consists of multiple lipases that share a similar sequence structure at the genetic and protein level, thus indicating a common ancestral origin.…”

The relevance of hydrophobic segments in multiblock copolyesterurethanes for their enzymatic degradation at the air-water interface

“…During the degradation of the polymeric films short water-soluble fragments are formed. The degradation of PCL is accelerated in bulk studies as well as in 2D monolayer investigations by different types of lipases, for instance the lipase from Porcine pancreas [25], Pseudomonas alcaligenes [26], or Pseudomonas cepacia [27]. Lipases are able to hydrolyze triacylglycerols and other ester bonds.…”

Unique Size‐Change Behavior of Photo‐Crosslinked Cinnamic Acid Derivative Nanoparticles during Hydrolytic Degradation

“…[1][2][3][4][5][6][7] We have rigorously studied the self-assembling of synthetic [8,9] and biodegradable [10][11][12][13] nanoparticles and hollow capsules [14,15] for biomedical applications such as drug delivery systems (DDS) and diagnosis. In the use of degradable nanoparticles, there is a limitation due to a lack of response to environmental changes such as pH, temperature, electric, magnetic, and light stimuli.…”