Filter paper blotting

Filter paper Blotting paper Insulating, board Newsprint paper i tique book paper Lined straw board Super-calendered book paper... 

Insulating board Filter paper Blotting paper Newsprint paper Antique book board Lined strawboard Supercalendered book paper Tagboard Bond paper Railro board Solid binders board Press board Vegetable parchment... 

A piece of sodium metal stored under kerosene m a metal container is removed from ajar and blotted with dry napkin or filter paper With a sharp knife, the layer of oxides IS removed until a shiny surface appears The removed layer is then destroyed carefully by adding very small pieces (not larger than 0 5 cm) to precooled 200 mL of methanol or ethanol... 

When the adjustment has been completed, rinse the capillary well with a stream of distilled water from a wash bottle and then dry by blotting with filter paper. Insert the capillary through an inverted cone of quantitative filter paper and clamp vertically over a small beaker. Lower the levelling bulb until the mercury drops just cease to flow,... 

In 1987, CL started to be applied in DNA hybridization assays as an alternative to the use of radioactive tags. These assays are based on the specificity of a binding process that of DNA strands for each other. An unknown DNA can be identified with the Southern blot method in which the strands of the analyte are separated and allowed to interact with labeled probe DNA strands on nitrocellulose filter paper. If the label on the probe is detected, the DNA can be identified and, in some cases, quantitated. Conventionally, radioactive tags were used be-... 

In a 1-1. three-necked flask equipped with a dry ice-acctone condenser and a sealed mechanical stirrer is placed 700 ml. of commercial, anhydrous, liquid ammonia. To the stirred ammonia is added a small piece of potassium metal. (Caution1 Care should he exercised in handling potassium metal, since it is extremely reactive and it ignites on contact with water, atmospheric moisture, or alcohol. It should he manipulated under toluene or xylene, and blotted with filter paper before addition.) After the appearance of a blue color a few crystals of ferric nitrate hydrate (ca. 0.1 g.) are added, followed by small pieces of freshly cut potassium metal until 7.0 g. (0.18 g. atom) has been added. After all the potassium has been converted to the amide (Note 7), 24.9 g. (0.154 mole) of sodio-2-formyl-6-methylcyclohexanone is added carefully through a powder funnel (Note 8). After 1 hour a solution of 28.2 g. (0.21 mole) of w-butyl bromide (Note 9) in 50 ml. of anhydrous ether is added dropwise from an addition funnel. The mixture is stirred for 3 hours, and then the dry ice-acetone condenser is replaced by a water condenser. A steam bath is placed under the flask, and the ammonia is evaporated (Caution ) as 400 ml. of anhydrous ether is added. When the... 

Place several layers of filter paper on a smooth, hard surface, and place a blotting membrane on top (see Fig. 1). Depending on the size of the tissue, use a single- or double-edged razor blade to cut a tissue section 0.2-2.0 mm thick, depending on the particular tissue sample. It is necessary... 

The lithium wire or ribbon is cut in about 0.25-g. pieces, stored under kerosene, and blotted with filter paper before addition. 

In semidry blotting, the gel and membrane are sandwiched horizontally between two stacks of buffer-wetted filter papers in direct contact with two closely spaced solid-plate electrodes. The close spacing of the semidry apparatus provides for high field strengths. The term semidry refers to the limited amount of buffer that is used in the stacks of filter paper. 

Using a forceps, lift the blot from the substrate and drain off the excess solution by placing the tip of the blot on a filter paper. 

The semi-dry blotting apparatus consists of two plates (anode and cathode) made from graphite, glassy carbon, or stainless steel and a sandwich consisting of buffer-soaked filter paper, transfer... 

The SDS-PAGE gel is agitated for few minutes in Soln. B and then put onto the membrane. Some layers of filter paper soaked in Soln. C finish the sandwich. The blotting apparatus is covered with the cathode plate and the electrodes are plugged into the power supply. Electrotransfer is performed with a constant current of 0.8 mAlcrc of gel area for 0.5-2 h at RT. The voltage does not exceed 15 V. 

Stained blots are dried on air on a sheet of filter paper. If radioactive compounds are also transferred, autoradiography of the dry membrane is possible at -70 °C. 

CapiUary blotting is recommended, if the gel is mounted onto a impermeable carrier. Put the affinity membrane with the coated face towards the gel onto the gel, cover the backside of the membrane with several layers of dry filter paper, wrap the stack into a water-tight foil, and store it under moderate pressure in a refrigerator for several hours or overnight. 

Once the transfer is completed, the blotting system is carefully disassembled. The filter paper and gel are removed and the membrane is placed in TBS buffer for 10 min. Finally, the membrane is soaked in blocking buffer for 60 min. 

FIGURE 3.8 Setup for a Southern blot. The agarose gel containing the separated DNA is placed in contact with a nitrocellulose sheet, then pressed with filter paper and paper towels. The buffer in the wet gel moves by capillary action into the filter paper and towels the lower reservoir of buffer helps promote the migration of the DNA from the gel onto the nitrocellulose sheet. 

Relative ranking of crosslink densities - The apparent crosslink density was determined by swelling the rubber samples in toluene as solvent. The vulcanized samples of 20 x 20 mm2 size were cut from a 2 mm sheet and immersed in 100 mL of toluene at room temperature for 72 h [51]. The solvent was renewed after 24 h. The sample was removed, blotted quickly with filter paper, and weighed. The samples were collected and left for 24 h in vacuo at 105°C to evaporate the solvent. The swelling value Q, defined as grams of toluene per gram of rubber hydrocarbon, was calculated as ... 

A 1-1. three-necked flask is equipped with a mercury-sealed stirrer, an inlet tube, and a reflux condenser which is connected through a soda-lime tube to a gas-absorption trap.1 The apparatus is dried in an oven and assembled rapidly to exclude moisture it is advisable to set up the apparatus in a hood to vent ammonia which may escape by accident. The flask is cooled in a Dry Ice-trichloroethylene bath, and 200 ml. of anhydrous (refrigeration grade) ammonia is introduced through the inlet tube from an ammonia cylinder which is either inverted or equipped with a siphon tube. Just before the apparatus is assembled, 8.1 g. (0.35 gram atom) of sodium is cut, weighed, and kept under kerosene in a small beaker. The Dry Ice bath is removed, the inlet tube is replaced by a rubber stopper, and a crystal of hydrated ferric nitrate (about 0.2 g.) is added. A small (about 5-mm.) cube of the sodium is cut, blotted rapidly with filter paper, and added quickly to the liquid ammonia. The solution is stirred until the blue color disappears, after which the remainder of the sodium is added in narrow, thin strips about as rapidly as... 

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-... 

If the membrane is to be stored at this stage place it between 2 sheets of filter paper (Whatman 3MM) to dry and store at 4°C (see Note 2). If not stored, continue straight on to the next stage (Section 3.2., step 2). Do not allow the blot to diy out. 

Stop the reaction by pouring off and discarding the staining solution, and rinse the membrane briefly m two changes of distilled water. The membrane can then be dried between filter paper and, once diy, can be photographed for a permanent record. The image will remain on the blot if it is stored in the dark, but otherwise will fade with time... 

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