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1 Introduction

Blue defeated the grand master Garry Kasparov in chess. More effective techniques of

computer learning coupled with smaller and smaller transistors, and thus faster and

faster processing speeds, have resulted in constant improvement and are impressive

feats of artificial intelligence.

1.6 Detection Methods

Before a signal can be analyzed, it has to be detected. But before a compound can

be detected it often has to be isolated or purified. In Organic Chemistry, one of the

most common separation techniques is column chromatography (Figure 1.48). Column

chromatography uses a solid and a liquid phase. The sample mixture is dissolved in

the liquid phase, then moved through the solid phase. Interacting with the solid and

the liquid molecules, the different compounds are held back differently and thus are

separated. That interaction can be based on different polarity, charge, or size. High-

pressure liquid chromatography (HPLC) is a column-chromatography that is based on

polarity differences, gel-permeation chromatography (GPC, also called size-exclusion-

chromatography, SEC) is based on size differences (Figure 1.49), and ion-exchange chro-

matography (IEC) is based on charge differences. Sometimes, special solid phases are

prepared that are molecularly imprinted. Basically, the polymer for the solid phase is

Figure 1.48: Column chromatography. The different components of the loaded sample adhere differently

to the solid and the liquid phase. Compounds with good solubility in the liquid phase and poor adhesion to

the solid phase will elute first.