Evaluation of asymmetric poly(vinyl alcohol) membranes for use in artificial islets

Young, Tai‐Horng; Yao, Nan-Kuang; Chang, R K; Chen, Leo‐Wang

doi:10.1016/0142-9612(96)00043-9

Cited by 66 publications

(39 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the characteristics of easy preparation, good biodegradability, excellent chemical resistance, and good mechanical properties, PVA has been used on many biomaterial applications [8]. For example, PVA membranes have been used in the artificial pancreas [9,10], hemodialysis [11], and implantable biomaterials [12,13]. Since chitosan contains hydroxyl and amine groups, it is potentially miscible with PVA due to the formation of hydrogen bonds [12,14].…”

Section: Introductionmentioning

confidence: 99%

Studies of chitosan: II. Preparation and characterization of chitosan/poly(vinyl alcohol)/gelatin ternary blend films

Chen

Wang

Mao

et al. 2008

International Journal of Biological Macromolecules

155

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Studies of chitosan: II. Preparation and characterization of chitosan/poly(vinyl alcohol)/gelatin ternary blend films

Chen

Wang

Mao

et al. 2008

International Journal of Biological Macromolecules

155

View full text Add to dashboard Cite

“…Practically, physical PVA hydrogels show a good biocompatibility, which makes them of high interest to the biomedical field. They have been widely studied as a constitutive material for biomembranes (15,16), cell encapsulation (17,18), or soft-tissue reconstruction (4,19). In that respect, several methods have been developed to induce the gelation of PVA, using solvent evaporation (20), thermal treatments by freezing-thawing (19), coagulation in poor solvent (15), or salting out (21).…”

Section: Significancementioning

confidence: 99%

Hydrogel films and coatings by swelling-induced gelation

Moreau

Chauvet

François

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Hydrogel films used as membranes or coatings are essential components of devices interfaced with biological systems. Their design is greatly challenged by the need to find mild synthesis and processing conditions that preserve their biocompatibility and the integrity of encapsulated compounds. Here, we report an approach to produce hydrogel films spontaneously in aqueous polymer solutions. This method uses the solvent depletion created at the surface of swelling polymer substrates to induce the gelation of a thin layer of polymer solution. Using a biocompatible polymer that self-assembles at high concentration [poly(vinyl alcohol)], hydrogel films were produced within minutes to hours with thicknesses ranging from tens to hundreds of micrometers. A simple model and numerical simulations of mass transport during swelling capture the experiments and predict how film growth depends on the solution composition, substrate geometry, and swelling properties. The versatility of the approach was verified with a variety of swelling substrates and hydrogel-forming solutions. We also demonstrate the potential of this technique by incorporating other solutes such as inorganic particles to fabricate ceramic-hydrogel coatings for bone anchoring and cells to fabricate cell-laden membranes for cell culture or tissue engineering. H ydrogel films are used in a number of biomedical applications like wound healing (1), drug delivery (1), antiadhesive membranes (2), soft-tissue reconstruction (3, 4), and cell culture (5). The quality of their interactions with biological tissues or entrapped cells is central to the performance of these systems. Although considerable advances have been made in synthesis (6) and processing (7) to tailor these interactions, the toxicity of by-products and the degradation caused by harsh processing conditions remain key issues (8), which can be overcome (9) but are often addressed at the cost of difficult synthesis or multistep processes. There is a great interest for simple, versatile, and in vivo-friendly methods to fabricate and modify hydrogels. We propose a strategy to design hydrogel films in mild conditions. This method could be used to produce freestanding hydrogel membranes or hydrogel coatings to functionalize other hydrogels.Our approach relies on the understanding of transport phenomena occurring near the surface of a polymer network swelling in a polymer solution. As an illustration, let us consider a flat polymer network with thickness H 0 immersed in a solution containing a volume fraction Φ 0 of free polymer chains, as depicted in Fig. 1A. When the solvent of the solution is also a solvent for the network, the network swells in a diffusive process. For early immersion times t, the increase in thickness ΔH is given by the following (10, 11):where H ∞ is the thickness at equilibrium swelling in the polymer solution and D 0 is a diffusivity coefficient depending on the dynamics of the network and of the solution. The systems of interest are those where the chains in solution do not penetrate...

show abstract

“…In particular, high-water-content PVA-H has been reported to have selective permeability, permeating low-molecularweight nutritional substances such as glucose and protein, but not substances at the cell-size level such as fibroblasts and leukocytes. 13,14 In addition, the gel prevents adhesion by preventing cell survival on its surface.…”

Section: Introductionmentioning

confidence: 99%

Development of the shields for tendon injury repair using polyvinyl alcohol — hydrogel ( PVA‐H)

Kobayashi

Toguchida

Oka

2001

J. Biomed. Mater. Res.

View full text Add to dashboard Cite

In recent years, marked advances have been made in repair techniques for tendon injury, but the treatment of finger flexor tendon injury is still one of the most difficult and important problems in the orthopedic field. The main problem in tendon repair is adhesion between the tendon and surrounding tissue. To prevent this adhesion and achieve tendon union, we developed adhesion preventive shields for tendon repair using polyvinyl alcohol hydrogel ( PVA-H) with 90% water content, and carried out an implant experiment using the deep flexor tendon of the third toe of domestic fowl. Injured tendons shielded with PVA-H showed union at about 3 weeks after the operation without adhesion to the surrounding tissue and good function such as gliding and range of motion. Neither breakage of the PVA-H shield itself nor infection, nor degeneration in the surrounding tissue were observed. These results confirmed that the tendon itself has repair ability, and the tendon is regenerated by synovial nutrition through PVA-H. High water content PVA-H may have clinically potential and be applicable to adhesion-preventive shields for tendon repair. However, re-rupture was observed, probably due to accidental tendon injury at an early period after the operation. In some cases, tendon immobilization methods to prevent re-rupture might be necessary.

show abstract

Evaluation of asymmetric poly(vinyl alcohol) membranes for use in artificial islets

Cited by 66 publications

References 15 publications

Studies of chitosan: II. Preparation and characterization of chitosan/poly(vinyl alcohol)/gelatin ternary blend films

Studies of chitosan: II. Preparation and characterization of chitosan/poly(vinyl alcohol)/gelatin ternary blend films

Hydrogel films and coatings by swelling-induced gelation

Development of the shields for tendon injury repair using polyvinyl alcohol — hydrogel ( PVA‐H)

Contact Info

Product

Resources

About