Affinity chromatography: A review of trends and developments over the past 50 years.

The field of affinity chromatography, which employs a biologically-related agent as the stationary phase, has seen significant growth since the modern era of this method began in 1968. This review examines the major developments and trends that have occurred in this technique over the past five decades. The basic principles and history of this area are first discussed. This is followed by an overview of the various supports, immobilization strategies, and types of binding agents that have been used in this field. The general types of applications and fields of use that have appeared for affinity chromatography are also considered. A survey of the literature is used to identify major trends in these topics and important areas of use for affinity chromatography in the separation, analysis, or characterization of chemicals and biochemicals.

Affinity chromatography: a historical perspective.

Affinity chromatography is one of the most selective and versatile forms of liquid chromatography for the separation or analysis of chemicals in complex mixtures. This method makes use of a biologically related agent as the stationary phase, which provides an affinity column with the ability to bind selectively and reversibly to a given target in a sample. This review examines the early work in this method and various developments that have lead to the current status of this technique. The general principles of affinity chromatography are briefly described as part of this discussion. Past and recent efforts in the generation of new binding agents, supports, and immobilization methods for this method are considered. Various applications of affinity chromatography are also summarized, as well as the influence this field has played in the creation of other affinity-based separation or analysis methods.

The lower the better: target values after LDL-Apheresis and semi-selective LDL-elimination therapies.

Prior to 1980 the drug therapy of hereditary hypercholesterolaemia was, as compared to nowadays standards, rather limited. There was virtually no effective therapy for homozygous patients, though plasma exchange introduced in France and Britain, demonstrated the use-fullness of the introduction of apheresis techniques. Parallel to the improvement of cholesterol lowering drug therapy for heterozygous patients, apheresis was developed as therapeutic affinity chromatography since 1980 at the university of Cologne for both homozygous and therapy refractory heterozygous patients. This development was named LDL-Apheresis based on the specificity for the removal of Apoprotein B bound cholesterol, the capacity due to the development of a repetitive cycling technique and the economy determined from the reuse of affinity chromatography columns for each single patient. The capacity of the system allowed for the introduction of new standards of post-treatment values such as 100mg/dl total cholesterol or alternatively 50mg/dl LDL-cholesterol and if cholesterol lowering drugs can also applied for a limited extent the rebound can be also slowed down. After 33 years of experience with seven homozygotes and 32 heterozygotes without treatment alternative, we found that in addition to the improvement of the quality of live the extension of live expectancy are the real proof of a therapeutic success as compared to other diagnostic procedures. The average live expectancy of our seven homozygous patients is 45.6 years; our oldest heterozygous patient is 81 years. There are no comparable long term data at present available neither from studies using drugs nor from subsequently developed apheresis techniques which also removed LDL-cholesterol together with plasma constituents not participating in the development of atherosclerosis. Also two homozygous patients giving birth to four children without complication support our concept of aggressive cholesterol lowering therapy being without major side effects (3-4% minor undesired reactions).

Affinity chromatography: history, perspectives, limitations and prospects.

Biomolecule separation and purification has until very recently steadfastly remained one of the more empirical aspects of modem biotechnology. Affinity chromatography, one of several types of adsorption chromatography, is particularly suited for the efficient isolation of biomolecules. This technique relies on the adsorbent bed material that has biological affinity for the substance to be isolated. This review is intended to place affinity chromatography in historical perspective and describe the current status, limitations and future prospects for the technique in modern biotechnology.

Biospecific or non-specific adsorption of amylase on starch in Starkenstein's experiments (1910)?

A paper by Starkenstein on the influence of chloride on the enzymatic activity of liver amylase, including a description of the adsorption of the enzyme on starch, is discussed with reference to the early concepts of enzyme-substrate binding and to later work on specific adsorption of amylase on starch.