Adsorption on mica

Adsorption on mica and plane surfaces of salts. Adsorption on different forms of carbon. ... 

Tsapikouni, T.S. and Missirlis. Y.R, pH and ionic strength effect on single fibrinogen molecule adsorption on mica studied with AFM, Colloids Surf. B. SI, 89, 2007. 

Radeva Ts, Netzel J, Petkanchin I. Stoylov S. Electro-optic study of neutral polymer adsorption on mica. J Colloid Interface Sci 1993 160 493-495. 

By adsorption on certain surfaces it is possible so to adsorb pseudoisocyanin from solutions, in which no association is possible, that the association band makes its appearance. This phenomenon occurs especially on mica, while glass and quartz are also suitable (see Skerlak ). The previous considerations make it already possible for us to see what conditions such a surface must satisfy naturally there must be negatively charged spots at which the positive dye ions will be attached. This adsorption does not succeed with polystyrene for example and this must be due to the non-polar character of this substance. Such an adsorption on mica apparently forces the molecules of the dye into a particular position so that the structure of the adsorbed layer becomes similar to that of the micelles. Not exactly so, since the spectral band is somewhat displaced on most adsorbents. Skerlak s investigation on the adsorption of pseudoisocyanin on mica gives a beautiful confirmation of this hypothesis. The molecules of the dye stand perpendicular to the adsorbiiig surface. 

Fig. 3 a-c. Summary of data from different laboratories, obtained by surface force measurement, on the average layer thickness L as a function of tethered chain length for flat, tethered layers constructed by adsorption of amphiphilic polymers on mica. Adapted from Ref. 21. (a) Data of reference 20 on poly-tert-butylstyrene chains anchored by adsorbing blocks of poly-2-vinylpyridine. (b) Data of references 11 and 12 on polystyrene chains anchored by adsorbing blocks of poly-2-vinylpyridine. (c) Data of references 13 and 14 on polystyrene chains anchored by adsorbing zwitterionic groups [13] or by small adsorbing blocks of polyethyleneoxide [14]... 

Resch, R. Prohaska, T. Friedbacher, G. Grasserbauer, M. Kanniainen, T. Lindroos, S. Leskela, M. Niinisto, L. Broekaert, J. A. C. 1998. In-situ investigation of ZnS deposition on mica by successive ionic layer adsorption and reaction method as studied with atomic force microscopy. Fresenius J. Anal. Chem. 353 772-777. 

Measurements of the adsorption of carbon monoxide on mica were made at two temperatures (Bawn, JACS 54 72, 1932). A slight correction should be made for adsorption on the glass vessel wall but is not made here. The pressure units are Torr/1000, and the adsorption is (ml STP)/100. 

Fig. 6 AFM topographic images (a-d, i, j) and cross sections (e, f, k, I) of a miktoarm PS-P2VP star copolymer adsorbed on mica from chloroform (a-c, e), from THF (d, f) and from acidic water (HC1, pH = 2) in salt free (i, k) and in the presence of 1 mM Na3P04 (j, I). Schematic representation of the solution conformations and conformations in adsorbed state of the PS-P2VP in chloroform (g), THF (h), in water at pH = 2 before (n) and after adsorption (m) respectively (PS arms in red, P2VP ones in blue). Reprinted with permission from [116]. Copyright (2003) American Chemical Society...

FIG. 4. Many STM experiments performed under ambient conditions incorporate SECM phenomena associated with water adsorption on surface due to the ambient humidity. In some instances the SECM signal may be dominant as in the case of imaging bulk insulators such as mica. (From Ref. 50.)... 

Fig. 18a,b. Amplitude micrographs of arborescent graft polyethylene on mica obtained by tapping mode SFM after a adsorption from a dilute solution in hot xylene b annealing for 24 hat 150 °C... 

Earlier attempts to use the AFM for mechanically stretching chromatin fibers have run into a rather unexpected artifact. Long native chromatin fibers isolated from chicken erythrocytes, or fibers assembled in vitro from purified histones and relatively short, tandemly repeated DNA sequences were deposited on mica or glass surfaces and pulled with the AFM tip [69,70]. In such stretching experiments the scanning of the sample in the x- and y-direction used for imaging was disabled, and the cantilever-mounted tip was allowed to move only in the z-direction, i.e., upwards and downwards, away and towards the surface. When the AFM tip is pushed into the sample, it may attach to the sample by non-specific adsorption upon retraction it stretches the sample and force-extension curves are recorded (see Fig. lb for an explanation of a typical force curve). 

From the experimental data, pFNs versus p can be plotted. The plot will be linear, and the slope is equal to 1/Nsm. The intersection gives a. Charcoal is found to adsorb 15 mg of N2 as monolayer. Another example is that of adsorption of N2 on mica surface (at 90 K). The following data were found ... 

Langmuir adsorption is found for the data of nitrogen on mica (at 90 K). The data were found to be... 

Whitehouse C, Fang J, Aggeli A, Bell M, Brydson R, Fishwick CWG, Henderson JR, Knobler CM, Owens RW, Thomson NH, Smith DA, Boden N. Adsorption and self-assembly of peptides on mica substrates. Angew Chem Int Ed 2005 44 1965-1968. 

Fig.25. Surface structures formed on mica upon adsorption of P(S-fc-4VP) 330-130 from chloroform [279]. The 2.5x2.5 pm2 height images were obtained by contact mode SFM. Depending on the solution concentration, the morphology developed from small islands on the left to lamellar morphology on the right. The solution concentrations are indicated above the micrographs. The drawing below illustrates the transition from the A dot-like to B stripe-like morphology caused by variation of the block-length ratio. Courtesy of P. Eibeck and M. Moller...

Fig.63. SFM-micrographs of the monolayers on a HOPG and b mica prepared by spin casting of 14-ABG-PS solutions in cyclopentane (c=0.1 mg/ml). Individual molecules in (a) aligned parallel to the substrate and bent at characteristic angles of 60 ° and 120 °. This indicates epitaxial adsorption of the alkyl tails according to the three fold symmetry of graphite. The worm-like molecules in (b) wound around each other and resulted in a felt-like structure [596]. The inserts illustrate specific interaction of the side chains with HOPG (a) and their absence on mica (b)...

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