Nanochannels

Conventional channels Mini-channels Micro-channels Transitional channels Molecular nanochannels... 

Hashimoto T., Tsutsumi K., and Funaki Y., Nanoprocessing based on bicontinuous microdomains of block copolymers Nanochannel coated with metals, Langmuir, 13, 6869, 1997. 

Secondly, we describe the site-selective introduction of a functional molecule, tetrakis-5,10,15,20-(4-carboxyphenyl)porphyrin (TCPP), into the microphase separation structure of a diblock copolymer film of PS-fo-P4VP. Since porphyrin derivatives show various functionalities such as sensitization, redox activity, and nonlinear optical effect, a polymer nanodot array containing a porphyrin at a high concentration would be applicable to a light-harvesing and charge transporting nanochannel. 

Zhou, Y. and Shimizu, T. (2008) Lipid nanotubes a unique template to create diverse one-dimensional nanostructures. Chemistry of Materials, 20 (3), 625-633. Nogawa, K., Tagawa, Y., Nakajima, M., Arai, F., Shimizu, T., Kamiya, S. and Fukuda, T. (2007) Development of novel nanopipette with a lipid nanotube as nanochannel. Journal of Robotics and Mechatronics, 19 (5), 528-534. 

S.E. Letant, T.W. van Buuren, and LJ. Terminello, Nanochannel arrays on silicon platforms by electrochemistry. Nano Lett. 4, 1705-1707 (2004). 

Fig. 7 Novel patternable block copolymers to achieve spatially controlled nanostructures, a An asymmetric PaMS-fc-PHS copolymer/photoacid generator/crosslinker solution was spin-coated on a silicon substrate and formed vertical PaMS cylinders due to rapid solvent evaporation, b 248 nm stepper exposure and subsequent development to form micropatterns with features as small as 400 nm. c Strong UV irradiation under high vacuum to remove PaMS, thus generating patterned nanochannels...

Interestingly, CNTs have been shown to be able to deliver exogenous genes not only in mammalian cells, but also in bacteria. Rojas-Chapana et al. (2005) demonstrated that oxidised, water-dispersible CNTs can deliver pDNA into E. coli (ratio of transformation efficiency/transformants of about 32) by opening up temporary nanochannels across the cell envelope. The authors described that addition of CNTs in a suspension containing E. coli and pDNA and application of a microwave frequency resulted in the orientation of the CNT tips perpendicularly to the cell surface and subsequently plasmid delivery into the bacteria. 

Ding, J., Chuy, C. and Holdcroft, S. 2001. A self-organized network of nanochannels enhances ion conductivity through polymer films. Chemistry of Materials 13 2231-2233. 

The side chain separation varies in a range of 1 nm or slightly above. The network of aqueous domains exhibits a percolation threshold at a volume fraction of 10%, which is in line with the value determined from conductivity studies. This value is similar to the theoretical percolation threshold for bond percolation on a face-centered cubic lattice. It indicates a highly interconnected network of water nanochannels. Notably, this percolation threshold is markedly smaller, and thus more realistic, than those found in atomistic simulations, which were not able to reproduce experimental values. 

The general picture is such that the majority of excess protons are located in the central part of the hydrated hydrophilic nanochannels. In this region, the water is bulklike (for not too low degrees of hydration) with local proton transport properties similar to those described for water in Section 3.1.1.1.1. Therefore, the transport properties are indeed a function of the considered length and time scales,22 225 activation enthalpies of both... 

Figure 15. Crystal structure of 36 with perchlorate anions filled in the nanochannels.

Fig.1 Formation of reverse micelles in a self-assembled mixed surfactant system. The addition of water tends to link these droplets to form a highly viscous bi-continuous microemulsion with aqueous and isooctane nanochannels separated by the surfactants...

The addition of water-soluble polymers such as polyethylene oxide (PEO) or polyvinyl alcohol (PVA) into the synthetic mixture of the C TMAX-HN03-TE0S-H20 system (n = 16 or 18 X = Br or Cl) under shear flow is found to promote uniformity and elongation of rope-like mesoporous silica. The millimeter-scaled mesoporous silica ropes are found to possess a three-level hierarchical structure. The addition of water-soluble polymer does not affect the physical properties of the silica ropes. Moreover, further hydrothermal treatment of the acid-made material under basic ammonia conditions effectively promotes reconstruction of the silica nanochannels while maintaining the rope-like morphology. As a result, a notable enhancement in both thermal and hydrothermal stability is found. 

In previous literature, the type B hysteresis was ascribed to a lamellar-like structure that commonly observed in the pillared materials.[13,14] Here its existence in our mesoporous materials is associated with some internal defects in the channels. To further understand such hysteresis behavior, we compared the microtomed ultra-thin sections TEM micrographs of these two samples. In Fig. 2A, B, we show the typical parallel channels of MCM-41 and the well-ordered hexagonal mesoporous in pure silica sample(I). However in Fig. 2 C, D, one can obviously find the aluminosilicate(II) possessing the normal well-aligned MCM-41 nanochannels with extensive voids interspersed. The white void parts were attributed to the structural defects. These structural defects are not the lamellar form but the irregularly shaped defects. The size of the defects is not uniform and distributes between 5.0-30.0 nm. nanometers. Therefore, these aluminosilicate mesoporous materials were composed of structural defects-within-well-ordered hexagonal nanochannels matrix. 

Due to the existence of the structural defect, the nanochannels of the aluminosilicate mesoporous materials become more inter-connected than the pure silica MCM-41. The highly connected nanochannels could make the diffusion of large molecules inside the MCM-41 materials more effective. 

Allows a better dispersion of molybdenum trioxide from the external surface of the mesoporous support into its internal nanochannels. The active sites (possibly pairs of neighboring molybdenum cations) thus increases. As the result of better dispersion, the reduced molybdenum oxide species formed during the course of reaction through its entire surfaces and thus lowers the possibility of sintering in a reduced environment. Here, we see that the deactivation rate is the highest in Mo/Si02 catalyst due to the lowest surface area. 

D. Rensink, S. Fell, J. Roth, in Proceedings of the Sixth International Conference on Nanochannels, Microchannels and Minichannels, Darmstadt, Germany, 23-25 June 2008, pp. 1-7... 

Chung S, Lee JH, Moon MW, Han J, Kamm RD (2008) Non-lithographic wrinkle nanochannels for protein preconcentration. Adv Mater 20 3011-3016... 

Marti-Rujas, J., Desmedt, A., Harris, K. D. M., Guillaume, F., Direct time-resolved and spatially resolved monitoring of molecular transport in a crystalline nanochannel system. J. Am. Chem. Soc. 2004, 126, 11124-11125. 

Case Study 5 Imaging Nanochannels in Microfluidic Devices20... 

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