A novel class of fluorescent/superparamagnetic bifunctional nanoparticles was synthesized via the reverse microemulsion technique.These nanoparticles were studied with transmission electron microscopy(TEM) and SQUID microscopy.The results show that these nanoparticles have a typical diameter of 40 nm and a saturated magnetic moment of 1.9 emu/g at room temperature.The experiment results also show that these nanoparticles exhibit a strong excitonic photoluminescence.Then,these bifunctional nanoparticles were modified with vancomycin for binding.The results show that these vancomycin modified nanoparticles can capture selectively bacterias.
Molecularly imprinted polymers(MIPs) are artificial, template-made receptors with the ability to recognize and to specially bind the target molecule. The advantage of stability of the polymer, ease of the preparation and low cost of these MIPs have led to their assessment as substitutes for antibodies or enzymes in chemical sensors, catalysis and separations. Although creating a MIPs against small molecules is straightforward now, imprinting of large structures, such as proteins and other biomacromolecules, is still a challenge. The major problem associated with the imprinting of such large structures lies on the restricted mobility of them within highly cross-linked polymer networks and the poor efficiency in rebinding. In this paper, we present a technique for the preparation of polymer nanowires with the protein molecule imprinted and binding sites on surface. These surface imprinting nanowires exhibit highly selective recognition for a variety of template proteins, including albumin, hemoglobin and cytochrome c. Since the protein imprinted sites are located on, or close to, the surface, these imprinted nanowires have a good site accessibility towards the target protein molecules. Furthermore, the large surface area of the nanowires results in larger protein molecules binding capacity of the imprinted nanowires compared to previously report surface imprinting MIPs.
