Acquisition of a scintillation counter

许多重要的生物化学问题都与理解RNA-RNA、RNA-蛋白质、RNA-金属和蛋白质-金属之间的相互作用有关。这些相互作用中的大多数需要检测微量（10-14至10-6摩尔）的物质。然而，化学测试很少响应小于10-7摩尔。放射性示踪剂技术的发展减轻了这一限制，通过放射性示踪剂技术，对放射性同位素标记物质的异常灵敏的检测使得对10-12摩尔或更小量的许多物质的研究成为常规。此外，放射性的使用还为解决生物化学和分子生物学中的各种问题提供了强有力的实验方法。这包括同时跟踪两种物质或区分在不同时间合成的两种相同物质的双标记技术;在一种物质合成后的某个时间跟踪该物质而不干扰同时合成的其他物质的脉冲追踪法;以及测量反应参与程度的交换分析，仅举几例。虽然这些技术有很大的不同，但它们都依赖于放射性示踪剂的精确检测，而放射性示踪剂是这些技术的重要组成部分。出于这个原因，至关重要的是，我们的部门能够获得高性能的闪烁计数器，这将使我们能够准备准确的放射性示踪剂。

Many important biochemical questions are related to understanding interactions between RNA-RNA, RNA-protein, RNA-metal, and protein-metal. Most of these interactions require the detection of tiny (10-14 to 10-6 mole) quantities of material. However, chemical tests are rarely responsive to less than  10-7 mole. This limitation has been alleviated by the development of radiotracer technology through which extraordinarily sensitive detection of radioisotopically labelled material has allowed studies of many substances in quantities of 10-12 mole and smaller to become routine. In addition, the use of radioactivity has permitted the development of powerful experimental approaches to various types of problems in biochemistry as well as molecular biology. This includes the double-labelling technique for following two substances simultaneously or for distinguishing two identical substances synthesized at different times; the pulse-chase method for following a substance at a time after its synthesis without interference of other material that is concurrently synthesized; and the exchange analysis for measuring participation in reactions, to name only a few examples. Although these techniques are quite different, they all depend on the precise detection of radiotracers, which are essential components of these techniques. For this reason, it is crucial that our department has access to a high performance scintillation counter that will allow us to prepare accurate radiotracers.