Preparation and Characterization of Multifunctional Bionanomaterials and Their Biomedical Applications

Abstract

Nanotechnology is developed intensively for over past decade to peruse the new view and knowledge for new applications such as biomedicine. To match our demands, the nanostructure of nanomaterials gradually turns form single function into multifunction for treating various applications. In biomedicine fields, the biocompatibility and biodegradability of nanomaterials are significantly issue for the bio-safety. Hence, the biomodification of nanomaterials not only increases the degree of biosafety but also gives the nanomaterials the ability of biorecognition toward living cells.
In our studies, there are two main topics including the preparation of cell targeting and hyperthermia reagent. In the synthesis process, the biomaterials, such as chitosan, transferrin (Tf), are accepted for surface modification of nanomaterials owing their biocompatibility and biodegradability. The part of cell targeting nanomaterials is divided into two parts. First part is associated with the control of biomolecule modification, whose novel findings indicate that the modulation of targeting efficiency and rate are successfully achieved by quantitatively controlling Tf modification of nanoparticles via covalent modification. Second part is the first time to introduce hexametaphosphate to modify Au nanoparticle as stabilizer, the targeting nanomaterials is fabricated rapidly via electrostatic interaction and successfully applied in vitro. In aspect of hyperthermia, the two kind of hyperthermia reagents are prepared and successfully applied in hyperthermia treatment. The CTAB (cetyltrimethylammonium bromide) modified shaped Au nanomaterials with SPR (surface Plasmon resonance) in NIR (near infrared) region provides a useful light to heat converter as hyperthermia reagent. The replacement of CTAB by chitosan improves the biosafety of shaped Au nanomaterials. First proposal is that improvement of the thermal stability of Au nanomaterials become potential used as long-term hyperthermia reagent via chitosan modification. The second hyperthermia reagent, novel Au-NaYF4:Yb3+,Er3+ nanoparticles, is successfully fabricated. It is capable of providing the dual applications of call label and hyperthermia treatment based on the energy transfer and upconversion mechanism. In this section, the concept of cell targeting is introduced into the synthesis of Au-NaYF4:Yb3+,Er3+ nanoparticles. It is found to raise the hyperthermia efficiency a lot and consistent with the finding in part of cell targeting nanomaterials. Hence, the biomolecular modification strengthens the applicability and their related properties.