Synthesis And Release Behavior Of Zein-based Composite Hydrogel

At present, the drug carrier material mainly used synthetic biodegradable polymerand natural polymer. The former usually is cytotoxic and have poor biocompatibilityand biodegradability, the latter often lack some performance of pharmaceutical carrierrequired. Therefore a better solution is to get a composite of two materials, which canobtain an ideal drug carrier. Zein, as a plant-derived natural hydrophobic biomolecule,has good biocompatibility and biodegradability. It can protect the drug from theexternal environment to prevent degradation of the drug. Polyvinyl alcohol(PVA) is awater-soluble, non-toxic, semi-crystalline polymer. It has many hydroxyl groups. PVAis easily changed to hydrogels and has good mechanical property. Due to the goodperformance, PVA is widely used in biomedical, pharmaceutical and other fields.Alginate(SA) is a natural polysaccharide. Because of its unique biocompatibility,biodegradability, it is considered to be an excellent drug delivery carrier. Here, wecombined zein to PVA and SA respectively in order to obtain new zein-based polymerhydrogel carriers.Firstly, this paper introduces the basic structure and properties of prolamin,discusses the research progress of prolamin as drug carrier. Further this paper providesdetailed information on the research progress of wheat gliadin and zein as drugcarriers.Secondly, the Zein/PVA composite hydrogel was prepared through the freezingand thawing technique. Some important preparation factors were investigated. Thestructure and morphology of Zein/PVA composite hydrogel was characterized byFT-IR, DSC and SEM. It indicated that the biopolymers hydrogel mainly formedthrough hydrogen-bonded interactions and has better compatibility. The swelling anddegradation behavior of the Zein/PVA composite hydrogel were studied. It was foundthat Zein/PVA composite hydrogel has sensitivity to pH and ionic strength, and hasdegradability. These features make Zein/PVA composite hydrogels more suitable to bea pharmaceutical carrier.Thirdly, the Zein/SA composite hydrogel was prepared with CaCl2as crosslinkingagent. Some important preparation factors were investigated. The structure andmorphology of Zein/PVA composite hydrogel was characterized by FT-IR, DSC and SEM. It indicated that the hydrogel was successfully obtained and has bettercompatibility. The swelling and degradation behavior of the Zein/SA compositehydrogel were studied. It was found that Zein/SA composite hydrogel has sensitivity topH and ionic strength, and has degradability. These features make Zein/SA compositehydrogels more suitable to be pharmaceutical carrier.Finally, rhodamine B and bovine serum albumin were used as model drug to testthe drug release properties of zein-based composite hydrogels in vitro. The resultsshow that compared with the pure PVA and SA hydrogel, the encapsulation efficiencyand drug loading efficiency of the Zein/PVA and Zein/SA composite hydrogel wereincreased greatly. Compared with pure PVA and SA hydrogel, Zein/PVA and Zein/SAcomposite hydrogels have better drug delivery performance. Zein/PVA and Zein/SAcomposite hydrogel can protect drug under acidic condition and release slowly underalkaline conditions. But the BSA is difficult to fully release from the zein-basedcomposite hydrogels. It indicated that the composite hydrogels were suitable fordelivery of small molecule drugs.In conclusion, the preparation process of Zein-based composite hydrogels issimple, moderate and non-toxic. Zein-based composite hydrogels show good releaseproperties in vitro. This work broadens the study range of Zein drug carrier.Meanwhile, the Zein-based composite hydrogels have bright application prospect inbiomedical field.