Transfer capillary

C2. Chomczynski, P., One-hour downward alkaline capillary transfer for blotting of DNA and RNA. Anal. Biochem. 201, 134-139 (1992). 

The actual blotting process may be accomplished by one of two methods passive (or capillary) transfer and electroblotting. In passive transfer, the membrane is placed in direct contact with the polyacrylamide gel and organized in a sandwich-like arrangement consisting of (from bottom to top) filter paper soaked with transfer buffer, gel, membrane, and more filter paper. The sandwich is compressed by a heavy weight. Buffer passes by capillary ac-... 

The decrease of the liquid level above the tube by a quarter of diameter promotes the increase of the average heat transfer coefficient at low and moderate heat fluxes. The measuring of the temperature heads showed that it goes on due to surface superheat decrease in the unflooded part of a tube. It ean be explained with help of following point model. There is not boiling but evaporative meehanism of heat transfer in a sintered powder porous media with the capillary transfer of the liquid from the pool to the zone of heat release. 

Two approaches based on fast-atom bombardment (FAB) and introduced almost simultaneously were soon after their first description in 1985 and 1986 commercialized, i.e., the frit-FAB [80] and the continuous-flow Cf-FAB [81]. Both systems are used to introduce part of the column effluent (typically 1-10 pl/min) into a FAB somce. In the frit-FAB system, a capillary transfers the effluent to a stainless-steel or PFTE frit used as a FAB target, while in Cf-FAB system the effluent flows in a thin uniform film over the FAB target. A suitable FAB matrix, e.g., glycerol, should be added to the mobile phase. Analyte molecules are directly desorbed and ionized from the hqtrid film by FAB. These approaches are discussed in Ch. 4.6. 

This trap is not used in typical flash pyrolysis experiments. However, if the pyrolysate is generated for a longer period of time, and it is not delivered to the chromatographic column similarly to a typical injection, a cryofocusing attachment is necessary. In principle, this consists of a short tube through which passes a capillary transfer line (or part of the column). The cryofocusing tube can be cooled at subambient temperatures for a determined period of time and condenses the sample injected in the GC. At the start of the GC run, the cryofocusing tube can be rapidly heated to evaporate the condensate. 

Set up a capillary transfer pyramid using negatively charged nylon membrane and 10X SSC as the transfer buffer, Allow to transfer overnight. Fix the DNA to the membrane by baking or ultraviolet crosslinking... 

Capillary transfer has been the classic procedure but simplified modifications and different versions of vacuum blotting are becoming popular. Large fragments are not efficiently transferred and DNA is clipped into = 1 kb fragments between electrophoresis and transfer. 

A bidirectional capillary transfer (Smith and Summers, 1980) (Table 9.8C) is feasible for Southern analysis of DNA present in high... 

Downward alkaline capillary transfer to nitrocellulose, nylon or PVDF... 

D. Neutral capillary transfer of DNA from agarose to nylon... 

F. Alkaline capillary transfer of DNA from polyacrylamide gels to nylon membranes... 

Although RNA can bind as well as DNA to nitrocellulose, reproducible results are obtained only if RNA is carefully denatured. Among formaldehyde, glyoxal/DMSO, methylmercuric hydroxide, alkali and heat, the first two are most effective and give best binding, whereas alkali pretreatment can even be counterproductive (Thomas, 1983 Henderson et al., 1991). Recently, some attractive alternatives to these standard methods have become available (see below). The transfer of RNA from gel to membrane is as for DNA, of which the downward alkaline capillary transfer is the most attractive (Table 9.1 lA). 

Northern blot RNA was electrophoresed in formaldehyde denaturing agarose gel and blotted by capillary transfer to Hybond-N+ membrane (Amersham... 

DNA is denatured in the gel (RNA is denatured before electrophoresis) and the face of the gel slab is placed in contact with a membrane made of nitrocellulose, nylon, or another material. The single-stranded nucleic acid molecules are then transferred from the gel to the membrane by capillary transfer (blotting) or other methods. The membrane containing the blotted nucleic acids is called the blot. 

One way around this problem is to dispense with the trapping and separation stage by continuous sampling of the atmosphere around the Aermal probe. This can be achieved by using a small-bore silica-glass capillary transfer line which also serves to reduce the pressure fix)m atmospheric to that which could be accommodated by the ion source of the mass spectrometer. The capillary tube... 

Glass microfluidic chips with inserted nano-ESI emitters, electroosmotic pumping capillaries, or capillary transfer lines inserted in the liquid sheath interface of a Q-TOF instrument, were also used for the CE analysis of standard peptide/protein digests and of gel-isolated proteins from complex cellular extracts (H. influenza, P. Some of these chips enabled sam-... 

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