A Three‐Dimensional Nanostructured Array of Protein Nanoparticles

Abstract

to light-emitting diodes, fl ash memory devices, multifunctional nanoporous fi lms, etc. However, the fabrication processes are quite complex and exhibit signifi cant drawbacks, such as long stacking time, high cost, low yield, limited aspect ratio, and requirement of various chemicals and/or high processing temperatures. [7][8][9][10][11] Moreover, the fabricated systems are often not biocompatible and hence have limited application to biotechnology areas.Unlike polymer-based multilayer assembly, [12][13][14][15][16] layer-by-layer assembly and patterned arrays of biomaterials such as proteins and DNA require more sophisticated techniques owing to the complicated structures and functions of biomaterials. Several cases have been reported concerning the formation of simple, nonpatterned fi lms of two-or three-layered proteins using conventional streptavidinbiotin affi nity. [17][18][19][20] However, 3D patterned arrays of multilayered protein nanostructures have never been explored, despite the many potential applications in biological nanodevices for sensitive and multiplexed biodetection, 3D separation of biomaterials (cells, DNA, or proteins), [21][22][23] drug delivery, [ 24 ] optical devices [ 17,18 ] either using fl uorescent proteins or combining inorganic nanoparticles, and patterned and biocompatible scaffolds for cell or tissue culture. [24][25][26][27] Especially, it is expected that 3D patterned arrays of protein multilayers can signifi cantly contribute to enhancing biosensor performance. As recently reported, [ 28 ] detection sensitivity was signifi cantly enhanced using a 3D assay system based on probe antibodies attached to spherical nanoparticles and metal nanostructures with extremely enlarged surface area. To achieve simultaneously both sensitive and multiplexed assay, which seems essential to break through the current limit of sensor performance, [29][30][31] the 3D assay system needs to be fabricated from heterogeneous capture probes with the well-defi ned composition of each capture probe being maintained, and the fabrication process should be highly controllable as well. In the study reported here, we used bacterial protein nanoparticles as a platform for the sensor probe, that is, we genetically engineered the protein nanoparticles so that any antigenic peptides of interest should be displayed on the nanoparticle surface, by which means a vast number of different nanoparticles can be easily synthesized. Then, the engineered nanoparticles with surface-exposed A Three-Dimensional Nanostructured Array of Protein Nanoparticles DOI: 10.1002/adfm.201001144Here a novel technique is reported to construct a three-dimensional (3D) array of well-defi ned and controllable multilayered nanostructures of proteins that is based on alternate layer-by-layer assembly of bacterial protein nanoparticles and DNA on a patterned array of gold dots. This is the fi rst report on protein-based multilayer stacking, which has the following signifi cant advantages over conventional multilayer assemblies: 1) avoiding ha...

A variant of green fluorescent protein exclusively deposited to active intracellular inclusion bodies

“…Fluorescent protein nanoparticles can be used in bio-imaging, in vivo tracking of biomolecules and as tracers for intravascular imaging [ 40 , 41 ]. Here, an attempt was made to reduce the particle size of fluorescent DL4 IBs to explore the possibility of utilizing the biologically active DL4 IBs as fluorescent nanoparticles.…”

Fluorescent Ferritin Nanoparticles and Application to the Aptamer Sensor

“…coli strain BL21(DE3) [F – ompThsdS B (rB – mB – )] was transformed with the above expression vectors, and transformants with ampicillin resistance were finally selected. The detailed procedures for the isopropyl β- d -1-thiogalactopyranoside (IPTG)-induced gene expression and purification of the recombinant fluorescent ferritin nanoparticles and transmission electron microscopy (TEM) image analysis of the purified protein nanoparticles were well described in our previous reports. − …”

Multifunctional Protein-Enabled Patterning on Arrayed Ferroelectric Materials

“…The ability to control hierarchical assemblies of hybrid nanostructures and biological building blocks is essential for a wide range of practical biotechnological and diagnostics applications, as well as in fabrication of biomedical and biosensing devices. − One of the main challenges is the development of novel fabrication techniques that are flexible and low-cost but also able to precisely control layer-by-layer self-assembly at a molecular level and thus provide control over the biological and inorganic interfaces. The desired fabrication and processing conditions would ideally be environmentally benign and biologically compatible.…”

“…In the past few decades, several notable deposition methods have been developed to fabricate multilayered molecular solid films, among these techniques are atomic layer, Langmuir–Blodgett, and multilayer-deposition based on the use of various polymeric materials and self-assembled monolayers (SAMs) . Although used in many successful surface functionalization applications, these conventional deposition techniques and processes may also exhibit significant shortcomings. − , For example, the common thiol and silane SAMs bind to either noble metals or oxides, respectively, forming densely packed films onto a narrow range of solid surfaces. ,, A number of SAMs molecules, especially silanes, also require complex or nonbiocompatible reaction conditions. , Additionally, the biocompability associated with some of the SAMs components still remains in question limiting their wide range use in biotechnological and biomedical applications . In contrast, Langmuir–Blodgett films consisting of amphiphiles, assemble without the necessity of chemical bonding by mimicking a cell membrane. , Although the Langmuir–Blodgett technique allows control over film density and thickness, the expensive instrumentation, long fabrication periods, film instability, challenging optimization and transition between materials are limiting factors for practical applications in biotechnology. , …”