tailieunhanh - Molecular Biology Problem Solver 11

Molecular Biology Problem Solver 11. Sách được nhiều nhà khoa học có uy tín, nhiều kinh nghiệm trong nghiên cứu thực nghiệm trình bày những vấn đề thường hay phát sinh trong phòng thí nghiệm. Do vậy mà sách không trình bày các protocol hay quy trình như các sách khác, thay vào đó các tác giả sẽ trình bày các vấn đề nhằm giúp giúp đọc giả: Tự nâng cao khả năng chẩn đoán nguyên nhân khi gặp các vấn để về kỹ thuật, quy trình, hóa chất, thuốc thử trong quá trình thực nghiệm trong phòng thí. | How Can You Maximize the Lifetime of Your pH Meter Proper Usage If the manufacturer s instructions are followed and product ratings adhered to a quality meter should last many years. Protection of the meter from liquids wiping up spills and respectful use gives long life. If the meter is to be used in harsh environments use a meter rated rated for such work. For example a waterproof system is better suited for work in the field or on ships. Proper Cleaning Precipitates at the Electrode Junction The precipitate that forms at the electrode junction is crystallized potassium chloride from the inner filling solution. This KCl creep is created as the inner filling solution containing KCl comes through the junction when there is no sample or liquid on the external side of the junction. The water of the filling solution evaporates and crystals form. The creeping KCl should be rinsed away with deionized water and the filling solution height checked prior to putting the electrode back into service. Clogged Electrode Junctions There are several junction types and they require different cleaning techniques. Consult the instruction manual for your particular electrode. In general soaking or sonicating in a commercial cleaning solution for your sample type or a dilute hydrochloric acid solution can often remove sample buildup. Protein accumulation often requires a cleaning solution with pepsin for faster removal. After cleaning the filling solution chamber of the electrode should be flushed with copious amounts of deionized water then rinsed with filling solution several times. The filling solution rinses ensure that the electrode is put back into service with the proper concentration instead of a diluted filling solution. If your junction requires frequent cleaning a different reference system or filling solution should be investigated. A junction cannot always be sufficiently cleaned the electrode must be replaced. Proper Storage Precisely follow the manufacturer s .