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Temperature-responsive gelation of type I collagen solutions involving fibril formation and genipin crosslinking as a potential injectable hydrogel.

Yunoki S, Ohyabu Y, Hatayama H - Int J Biomater (2013)

Bottom Line: The PSC/genipin solutions exhibited fluidity at room temperature for at least 30 min, whereas the ASC/genipin solutions rapidly reached gel points.In specific cases PSC would be preferred over ASC as an injectable gel system.The temperature-responsive gelation of PSC/genipin solutions was due to temperature responses to genipin crosslinking and collagen fibril formation.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Group, Tokyo Metropolitan Industrial Technology Research Institute, 2-4-10 Aomi, Koto-ku, Tokyo 135-0064, Japan.

ABSTRACT
We investigated the temperature-responsive gelation of collagen/genipin solutions using pepsin-solubilized collagen (PSC) and acid-solubilized collagen (ASC) as substrates. Gelation occurred in the PSC/genipin solutions at genipin concentrations 0-2 mM under moderate change in temperature from 25 to 37°C. The PSC/genipin solutions exhibited fluidity at room temperature for at least 30 min, whereas the ASC/genipin solutions rapidly reached gel points. In specific cases PSC would be preferred over ASC as an injectable gel system. The temperature-responsive gelation of PSC/genipin solutions was due to temperature responses to genipin crosslinking and collagen fibril formation. The elastic modulus of the 0.5% PSC/genipin gel system could be adjusted in a range of 2.5 to 50 kPa by the PSC and genipin concentrations, suggesting that a PSC/genipin solution is a potential injectable gel system for drug and cell carriers, with mechanical properties matching those of living tissues.

No MeSH data available.


Storage modulus (G′) of the 0.5% PSC/1 mM genipin solution measured by a temperature-responsive gelation test. The temperature was maintained at 25°C for 1800 s and then increased to (a) 37, (b) 33, or (c) 30°C.
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fig5: Storage modulus (G′) of the 0.5% PSC/1 mM genipin solution measured by a temperature-responsive gelation test. The temperature was maintained at 25°C for 1800 s and then increased to (a) 37, (b) 33, or (c) 30°C.

Mentions: Temperature-responsive gelation tests were conducted for the 0.5% PSC/1 mM genipin solutions. The intervals at 25°C were set at 600, 1200, and 1800 s, during which the solutions remained viscous (Figure 2(c)). Sharp increases in G′ were observed approximately 100 s after the solutions reached the target temperature (37°C) (Figure 4), indicating that gelation was triggered by the increase in temperature to physiological temperature. The rates of modulus increase were not affected by the length of intervals at 25°C. Lower target temperatures (33 and 30°C) also were investigated. Figure 5 shows the results of temperature-response tests employing target temperatures of 30, 33, and 37°C and an interval of 1800 s. The rate of increase in G′ decreased with the target temperature, supporting the hypothesis that this gel system is temperature-responsive. The turbidity of the gels, corresponding to the actual fibril formation rate, tended to decrease with increase in the concentration of genipin.


Temperature-responsive gelation of type I collagen solutions involving fibril formation and genipin crosslinking as a potential injectable hydrogel.

Yunoki S, Ohyabu Y, Hatayama H - Int J Biomater (2013)

Storage modulus (G′) of the 0.5% PSC/1 mM genipin solution measured by a temperature-responsive gelation test. The temperature was maintained at 25°C for 1800 s and then increased to (a) 37, (b) 33, or (c) 30°C.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3814099&req=5

fig5: Storage modulus (G′) of the 0.5% PSC/1 mM genipin solution measured by a temperature-responsive gelation test. The temperature was maintained at 25°C for 1800 s and then increased to (a) 37, (b) 33, or (c) 30°C.
Mentions: Temperature-responsive gelation tests were conducted for the 0.5% PSC/1 mM genipin solutions. The intervals at 25°C were set at 600, 1200, and 1800 s, during which the solutions remained viscous (Figure 2(c)). Sharp increases in G′ were observed approximately 100 s after the solutions reached the target temperature (37°C) (Figure 4), indicating that gelation was triggered by the increase in temperature to physiological temperature. The rates of modulus increase were not affected by the length of intervals at 25°C. Lower target temperatures (33 and 30°C) also were investigated. Figure 5 shows the results of temperature-response tests employing target temperatures of 30, 33, and 37°C and an interval of 1800 s. The rate of increase in G′ decreased with the target temperature, supporting the hypothesis that this gel system is temperature-responsive. The turbidity of the gels, corresponding to the actual fibril formation rate, tended to decrease with increase in the concentration of genipin.

Bottom Line: The PSC/genipin solutions exhibited fluidity at room temperature for at least 30 min, whereas the ASC/genipin solutions rapidly reached gel points.In specific cases PSC would be preferred over ASC as an injectable gel system.The temperature-responsive gelation of PSC/genipin solutions was due to temperature responses to genipin crosslinking and collagen fibril formation.

View Article: PubMed Central - PubMed

Affiliation: Biotechnology Group, Tokyo Metropolitan Industrial Technology Research Institute, 2-4-10 Aomi, Koto-ku, Tokyo 135-0064, Japan.

ABSTRACT
We investigated the temperature-responsive gelation of collagen/genipin solutions using pepsin-solubilized collagen (PSC) and acid-solubilized collagen (ASC) as substrates. Gelation occurred in the PSC/genipin solutions at genipin concentrations 0-2 mM under moderate change in temperature from 25 to 37°C. The PSC/genipin solutions exhibited fluidity at room temperature for at least 30 min, whereas the ASC/genipin solutions rapidly reached gel points. In specific cases PSC would be preferred over ASC as an injectable gel system. The temperature-responsive gelation of PSC/genipin solutions was due to temperature responses to genipin crosslinking and collagen fibril formation. The elastic modulus of the 0.5% PSC/genipin gel system could be adjusted in a range of 2.5 to 50 kPa by the PSC and genipin concentrations, suggesting that a PSC/genipin solution is a potential injectable gel system for drug and cell carriers, with mechanical properties matching those of living tissues.

No MeSH data available.