西班牙瓊脂糖
技術(shù)參數(shù)：Agarose Low EEO
Gel Strength (1.0%) (g/cm2)………………≥750
Gelling Range (1.5%) (℃)………………36 - 39
Melting Range (℃)………………………87 - 89
EEO (-mr)……………………………………≤0.15
Sulfate (%)………………………………≤0.15
DNase……………………………………None Detected
RNase……………………………………None Detected
Protease………………………………None Detected
Introduction:
Routine use agarose is ideal for everyday analysis of nucleic acids by gel electrophoresis or blotting (Northern or Southern) and is also suitable for protein applications such as Ouchterlony and radial immunodiffusion (RID).
Analysis Note :
Sulfate content - used as an indicator of purity, since sulfate is the major ionic group present.
Gel strength- the force that must be applied to a gel to cause it to fracture.
Gel point- the temperature at which an aqueous agarose solution forms a gel as it cools. Agarose solutions exhibit hysteresis in the liquid-to-gel transition - that is, their gel point is not the same as their melting temperature.
Electroendosmosis (EEO) - a movement of liquid through the gel. Anionic groups in an agarose gel are affixed to the matrix and cannot move, but dissociable counter cations can migrate toward the cathode in the matrix, giving rise to EEO. Since electrophoretic movement of biopolymers is usually toward the anode, EEO can disrupt separations because of internal convection.
Preparation of Agarose Gels for DNA separations:
Weigh out the desired amount of agarose and place in an Erlenmeyer flask with a measured amount of electrophoresis buffer, e.g. for an 0.8% gel, add 0.8 gm of agarose and 100ml of TBE Buffer (1X), to a 200 ml flask. The larger flask insures against the agarose boiling over. Dissolve the agarose in a boiling water bath or in a revolving-plate microwave oven. All the grains of agarose should be dissolved and the solution clear. Cool the solution to 60°C ( 70°C for concentrations 2% or above) and pour immediately. Allow the gel to set for one-half hour before using. Make sure to use the same electrophoresis buffer in the gel as for the running buffer.
瓊脂糖
瓊脂（Agar），又名瓊膠、菜燕、凍粉，是一類從石花菜及其它紅藻類（Rhodophyceae）植物提取出來(lái)的藻膠（phycocottoid），在我國(guó)及日本已有三百多年（1658年）的歷史。瓊脂糖Agarose，縮寫為AG，是瓊脂中不帶電荷的中性組成成份，也譯為瓊膠素或瓊膠糖。瓊膠糖化學(xué)結(jié)構(gòu)由β-D-吡喃半乳糖(1-4)連接3,6-脫水α-L-吡喃半乳糖基單位構(gòu)成.
用途:瓊脂、瓊脂糖因?yàn)橛刑厥獾哪z凝性質(zhì)，尤其有顯著的穩(wěn)固性、滯度和滯后性，并且易吸收水分，有特殊的穩(wěn)定效應(yīng)；已經(jīng)廣泛使用于食用、醫(yī)藥、化工、紡織、國(guó)防等領(lǐng)域，據(jù)不完全統(tǒng)計(jì)，瓊脂、瓊脂糖的用途已有1000多種，被國(guó)際上稱為“新奇的東亞產(chǎn)品”。在食品工業(yè)中可用于生產(chǎn)：水晶軟糖、定型軟糖、水產(chǎn)品、肉類罐頭、果汁飲料、果肉飲料、米酒飲料、乳品飲料、精品、乳品蛋糕。
近年來(lái)由于其良好的生物相容性又廣泛用于生物分離介質(zhì)的生產(chǎn).
