Contribution of image analysis to the description of enzymatic degradation kinetics for particulate food material

Well-defined, semi-degradable polyester/polymethacrylate block copolymers, based on ε-caprolactone (CL), d,l-lactide (DLLA), glycolide (GA) and N,N′-dimethylaminoethyl methacrylate (DMAEMA), were synthesized by ring-opening polymerization (ROP) and atom transfer radical polymerization. Comprehensive degradation studies of poly(ε-caprolactone)-block-poly(N,N′-dimethylaminoethyl methacrylate) (PCL-b-PDMAEMA) on hydrolytic degradation and enzymatic degradation were performed, and those results were compared with the corresponding aliphatic polyester (PCL). The solution pH did not affect the hydrolytic degradation rate of PCL (a 3% Mn loss after six weeks). The presence of a PDMAEMA component in the copolymer chain increased the hydrolysis rates and depended on the solution pH, as PCL-b-PDMAEMA degraded faster in an acidic environment (36% Mn loss determined) than in a slightly alkaline environment (27% Mn loss). Enzymatic degradation of PCL-b-PDMAEMA, poly(d,l-lactide)-block-poly(N,N′-dimethylaminoethyl methacrylate) (PLA-b-PDMAEMA) and poly(lactide-co-glycolide-co-ε-caprolactone)-block-poly(N,N′-dimethylaminoethyl methacrylate) (PLGC-b-PDMAEMA) and the corresponding aliphatic polyesters (PCL, PLA and PLGC) was performed by Novozyme 435. In enzymatic degradation, PLGC degraded almost completely after eleven days. For polyester-b-PDMAEMA copolymers, enzymatic degradation primarily involved the ester bonds in PDMAEMA side chains, and the rate of polyester degradation decreased with the increase in the chain length of PDMAEMA. Amphiphilic copolymers might be used for biomaterials with long-term or midterm applications such as nanoscale drug delivery systems with tunable degradation kinetics.

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A new technique for measuring size distributions of fine ingesta/digesta particles

Wildlife Research ◽

10.1071/wr99010 ◽

2000 ◽

Vol 27 (2) ◽

pp. 191 ◽

Cited By ~ 6

Author(s):

Murray Logan ◽

Gordon D. Sanson

Keyword(s):

Image Analysis ◽

High Power ◽

Focal Plane ◽

Constant Volume ◽

New Technique ◽

Size Distributions ◽

Small Particles ◽

Microscope Slide ◽

Food Material ◽

A New Technique

Techniques were developed to enable convenient, high-power image analysis of (ingested) food material. A constant volume of diluted gut sample was delivered to a large microscope slide before being slowly evaporated in still air to leave all particles statically on the same focal plane. Evaporation also allowed a meniscus to develop around each particle, forcing them to separate and thereby preventing overlap and aggregation of particles. Sub-samples were measured under four high-power magnifications (2050, 1290, 510 and 190) to permit precise estimates of size distributions of the very small particles. The techniques developed avoid the need for large ingesta/digesta samples, sieving, and filtering, all of which have limited previous studies.

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Relationship between the molecular structure of duckweed starch and its in vitro enzymatic degradation kinetics

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2019.07.206 ◽

2019 ◽

Vol 139 ◽

pp. 244-251 ◽

Cited By ~ 1

Author(s):

Marcia Maria de Souza Moretti ◽

Wenwen Yu ◽

Wei Zou ◽

Célia Maria Landi Franco ◽

Liliane Lazzari Albertin ◽

...

Keyword(s):

Molecular Structure ◽

Enzymatic Degradation ◽

Degradation Kinetics

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In vitro enzymatic degradation kinetics of polymeric blends of crosslinked starch and carboxymethyl cellulose

Polymer International ◽

10.1002/pi.1878 ◽

2005 ◽

Vol 54 (11) ◽

pp. 1524-1536 ◽

Cited By ~ 43

Author(s):

AK Bajpai ◽

Jyoti Shrivastava

Keyword(s):

Carboxymethyl Cellulose ◽

Enzymatic Degradation ◽

Degradation Kinetics ◽

Polymeric Blends ◽

Kinetics Of

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A Microstructural Data Driven Multiscale Model for the Enzymatic Degradation and Remodeling of Collagen Networks

ASME 2011 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2011-53623 ◽

2011 ◽

Author(s):

Mohammad F. Hadi ◽

Edward A. Sander ◽

Jeffrey W. Ruberti ◽

Victor H. Barocas

Keyword(s):

Soft Tissue ◽

Enzymatic Degradation ◽

Soft Tissues ◽

Degradation Kinetics ◽

Multiscale Model ◽

Data Driven ◽

Fibrotic Disorders ◽

Collagenous Tissues ◽

Strain Dependent ◽

Microstructural Data

Collagen proteases actively participate in remodeling soft tissues. Recent work has demonstrated that metalloproteinases (MMP) and bacterial collagenases (BC) exhibit strain-dependent degradation kinetics [2]. Ascertaining how such nanoscale degradation shapes collagenous tissues at the macroscale is vital to our understanding of collagen management within tissues. As a first step towards this goal, we have developed a multiscale model for the enzymatic degradation and remodeling of collagen networks. Such a model will be useful in understanding the etiology of diseases related to collagen management (such as arthritis and fibrotic disorders), in simulating soft tissue development, and in helping engineer improved biomimetic tissues.

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Development of Polyoxymethylene/Polylactide Blends for a Potentially Biodegradable Material: Crystallization Kinetics, Lifespan Prediction, and Enzymatic Degradation Behavior

Polymers ◽

10.3390/polym11091516 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1516 ◽

Cited By ~ 5

Author(s):

Jianhua Li ◽

Yatao Wang ◽

Xiaodong Wang ◽

Dezhen Wu

Keyword(s):

Enzymatic Degradation ◽

Elevated Temperatures ◽

Degradation Kinetics ◽

Thermal Degradation Kinetics ◽

Solution Temperature ◽

Homogeneous State ◽

Degradation Behavior ◽

Biodegradable Material ◽

Critical Solution Temperature ◽

Twin Screw

This paper reported the development of polyoxymethylene (POM)/polylactide (PLA) blends for a potentially biodegradable material. A series of POM/PLA blends at different weight ratios were prepared by melt extrusion with a twin-screw extruder, and their mechanical properties, crystallization behavior and kinetics, thermal degradation kinetics and stability, lifespan prediction and enzymatic degradation behavior were investigated extensively. POM and PLA were found to be partially miscible in the melt state at low temperature and become phase-separated at elevated temperatures, and their blends exhibited a typical lower critical solution temperature behavior. There were two distinct glass transition temperatures (Tg) observed for POM/PLA blends at any mass ratios when quenched from the homogeneous state, and both POM and PLA domains showed an apparent depression in their respective Tg’s in the blends. Owing to the partial miscibility between two domains, the tensile strength and impact toughness of POM/PLA blends gradually decreased with an increase of PLA content, but their flexural strength and modulus presented an increasing trend with PLA content. The studies on non-isothermal and isothermal crystallization behaviors of the blends indicated that the crystallization rates of the blends decreased continually with increasing the PLA content, confirming that the crystallization of POM domain was controlled by the molecular-confined mechanism. The introduction of PLA into POM not only led to a slight increase of thermal stability of POM domain at low PLA contents but also shortened the lifespan of the blends, favoring the natural degradation of the blends. The POM/PLA blends exhibited an improvement in partially biodegradable performance with an increase of PLA content and their mass loss reached up to 25.3 wt % at the end of 48-h enzymatic degradation when 50 wt % of PLA was incorporated.

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Modified acellular porcine corneal matrix in deep lamellar transplantation of rabbit cornea

Journal of Biomaterials Applications ◽

10.1177/0885328219898372 ◽

2020 ◽

Vol 34 (8) ◽

pp. 1092-1104

Author(s):

Qian Wang ◽

Hang Zhou ◽

Yongqiang Sun ◽

Chengbo Cao ◽

Kunpeng Pang

Keyword(s):

Enzymatic Degradation ◽

Structural Integrity ◽

Degradation Kinetics ◽

Corneal Stroma ◽

Crosslinking Density ◽

Collagen Fibres ◽

Visible Light Range ◽

Structure And Ultrastructure ◽

Better Than ◽

Porcine Cornea

This study presents to develop a modified acellular porcine corneal matrix (MAPCM) to maintain high transparency, stability and biocompatibility as a rabbit deep cornea replacement using 1-ethyl-3–(3-dimethylaminopropyl)-carbodiimide crosslinking and a mild decellularization technique. Scaffolds are translucent and remain higher amount of glycosaminoglycans after decellularization than acellular porcine corneal matrix (APCM). Enzymatic degradation kinetics and mechanical properties of scaffolds are regulated by 1-ethyl-3–(3-dimethylaminopropyl)-carbodiimide -crosslinking density. The porous structure and ultrastructure of collagenous lamellae are maintained, and the pore size of MAPCM crosslinked with 0.5% (w/v) 1-ethyl-3–(3-dimethylaminopropyl)-carbodiimide is 13.26 ± 1.65 µm, similar to that of normal porcine cornea. The transmittance of MAPCM gets 79.1 ± 0.45 to 92.7 ± 1.4% in the visible light range. Results from a CCK-8 assay indicate that MAPCM gets higher cell proliferation rate of rabbit corneal stroma cells than APCM. Since collagen fibres structural integrity and regularity of MAPCM are retained after crosslinking, the opacity and stability of MAPCM are better than those of APCM within 4 weeks of animal implantation. In addition, there is no indication of an immune response or neovascularization in or around the transplanted disc. These results reveal that MAPCM may be a more suitable scaffold for corneal substitute construction.

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