The effect of the film-forming solution pH on the triple-helix content, thermal stability, and mechanical properties of gelatin films was investigated. The films were prepared from solutions at different pHs of type A pigskin gelatin, and their mechanical characteristics were determined. At pHs higher than 9 and lower than 5, Young’s modulus, E, and the stress at break, σb, of the films decreased significantly. Cross-linking with genipin reduced deformation at break, ϵb, and increased Young’s modulus. The intensity of the 1.1-nm X-ray diffraction reflection and the denaturation enthalpy decreased at these pHs, indicating that the triple helix reduced. Preliminary in vitro tests on the cross-linked samples indicated good cell proliferation and viability.
ManoJFSilvaGAAzevedoHSMalafayaPBSousaRASilvaSS. Natural origin biodegradable systems in tissue engineering and regenerative medicine: present status and some moving trends. J R Soc Interface2007; 4: 999–1030.
2.
BergoPSobralPJA. Effects of plasticizer on physical properties of pigskin gelatin films. Food Hydrocoll2007; 21: 1285–1289.
3.
LaiJYLinPKHsiueGHChengHYHuangSJLiYT. Low bloom strength gelatin as a carrier for potential use in retinal sheet encapsulation and transplantation. Biomacromolecules2009; 10: 310–319.
4.
PeptuCABuhusGPopaMPerichaudACostinD. Double cross-linked chitosan—gelatin particulate systems for ophthalmic applications. J Bioact Compat Polym2010; 25(1): 98–116.
5.
TucciMGRicottiGMattioli-BelmonteMGabbanelliFLucariniGOrlandoF. Chitosan and gelatin as engineered dressing for wound repair. J Bioact Compat Polym2001; 16: 145–157.
6.
BigiAPanzavoltaSRubiniK. Relationship between triple helix content and mechanical properties of gelatin films. Biomaterials2004; 25: 5675–5680.
7.
MuyongaJHColeCGBDuoduKG. Extraction and physico-chemical characterisation of Nile perch (Lates niloticus) skin and bone gelatin. Food Hydrocoll2004; 18: 581–592.
8.
LeickSDegenPKöhlerBRehageH. Film formation and surface gelation of gelatin molecules at the water/air interface. Phys Chem Chem Phys2009; 11: 2468–2474.
9.
IkadaYTabataY. Protein release from gelatin matrices. Adv Drug Deliv Rev1998; 31: 287–301.
10.
YoungSWongMTabataYMikosAG. Gelatin as a delivery vehicle for the controlled release of bioactive molecules. J Control Release2005; 109: 256–274.
11.
BigiABorghiMCojazziGFicheraAMPanzavoltaSRoveriN. Structural and mechanical properties of crosslinked drawn gelatin films. J Therm Anal Calorim2000; 61: 451–459.
12.
PezronIDjabourovMBosioLLeblondJ. X-ray diffraction of gelatin fibers in the dry and swollen states. J Polym Sci Part B: Polym. Phys1990; 28: 1823–1839.
13.
GornallJLTerentjevEM. Helix–coil transition of gelatin: helical morphology and stability. Soft Matter2008; 4: 544–549.
14.
BigiABracciBCojazziGPanzavoltaSRoveriN. Drawn gelatin films with improved mechanical properties. Biomaterials1998; 19: 2335–2340.
15.
AchetDHeXW. Determination of the renaturation level in gelatin films. Polym1995; 36: 787–791.
16.
YakimetsIWellnerNSmithACWilsonRHFarhatIMitchellJ. Mechanical properties with respect to water content of gelatin films in glassy state. Polym2005; 46: 12577–12585.
17.
MohantyBGuptaABohidarHBBandyopadhyayS. Effect of gelatin molecular charge heterogeneity on formation of intermolecular complexes and coacervation transition. J Polym Sci Part B2007; 45: 1511–1520.
18.
WangLAutyMAERauAKerryJFKerryJP. Effect of pH and addition of corn oil on the properties of gelatin-based biopolymer films. J Food Eng2009; 90: 11–19.
19.
BoaniniERubiniKPanzavoltaSBigiA. Chemico-physical characterization of gelatin films modified with oxidized alginate. Acta Biomater2010; 6: 383–388.
20.
FakirovSSaracZAnbarTBozBBaharIEvstatievM. Mechanical properties and transition temperatures of crosslinked oriented gelatin. I. Static and dynamic mechanical properties of cross-linked gelatin. Colloid Polym Sci1996; 274: 334–341.
21.
FakirovSSaracZAnbarTBozBBaharIEvstatievM. Mechanical properties and transition temperatures of crosslinked oriented gelatin. II. Effect of orientation and water content on transition temperatures. Colloid Polym Sci. 1997; 275: 307–314.
22.
BigiACojazziGPanzavoltaSRoveriNRubiniK. Stabilization of gelatin films by crosslinking with genipin. Biomaterials2002; 23: 4827–4832.
23.
MottaABarbatoBFossCTorricelliPMigliaresiC. Stabilization of Bombyx mori silk fibroin/sericin films by crosslinking with PEG-DE 600 and genipin. J Bioact Compat Polym2011; 26(2): 130–143.
24.
OfnerCMIIIBubnisWA. Chemical and swelling evaluations of amino group crosslinking in gelatin and modified gelatin matrices. Pharm Res1996; 13: 1821–1827.
25.
WardAG. The physical properties of gelatin solutions and gels. Br J Appl Phys1954; 5: 85–90.
26.
EysturskardJHaugIJUlsetASDragetKI. Mechanical properties of mammalian and fish gelatins based on their weight average molecular weight and molecular weight distribution. Food Hydrocoll2009; 23: 2315–2321.
27.
BigiACojazziGPanzavoltaSRoveriNRubiniK. Mechanical and thermal properties of gelatin films at different degrees of glutaraldehyde crosslinking. Biomaterials2001; 22: 763–768.
28.
TsaiCCHuangRNSungHWLiangHC. In vitro evaluation of the genotoxicity of a naturally occurring crosslinking agent (genipin) for biologic tissue fixation. J Biomed Mater Res2000; 52: 58–65.
29.
SungHWHuangDMChangWHHuangLLTsaiCCLiangIL. Gelatin-derived bioadhesives for closing skin wounds: an in vivo study. J Biomater Sci Polym Ed1999; 10: 751–771.
30.
PanzavoltaSGioffrèMFocareteMLGualandiCForoniLBigiA. Electrospun gelatin nanofibers: optimization of genipin crosslinking to preserve fiber morphology after exposure to water. Acta Biomater2011; 7: 1702–1709.
31.
GuarinoVAlvarez-PerezMCirilloVAmbrosioL. HMSC interaction with PCL and PCL/gelatin platforms: a comparative study on films and electrospun membranes. J Bioact Compat Polym2011; 26: 144–160.
