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Various types of simple separation on paper have been described as fore-runners of paper chromatography, among them a method of Runge in 1850, and the process called ‘capillary analysis’ (Goppelsroder, 1909). Such methods were really more like adsorption chromatography, and paper chromatography as it is now understood was a development of the partition system introduced by Martin and Synge in 1941 (see Chapter 2). One of the solids which can be used to support the stationary phase is cellulose powder (p. 38). Consden, Gordon and Martin[l] in 1944 separated the amino-acids and peptides in wool protein hydrolysates by a method in which the powder column was replaced by a sheet or strip of paper, freely suspended in a vapour-tight vessel.

Radioactive tracer techniques, coupled with chemical analysis by paper chromatography, became important in biochemical research in the late 1940’s, and today many investigations into intermediary and other aspects of metabolism rely on these methods. Soon after the marriage of chromatography to the use of tracers, various instruments were constructed which were able simultaneously to locate the positions of radioactive compounds on paper chromatograms and to determine the amount of radioactivity in each separated compound. Such devices are now available commercially in many different designs, and are intended for the scanning and counting of one-dimensional chromatograms only.

Assay of C14-labeled compounds isolated from metabolic experiments has been greatly aided by the high counting efficiency of liquid scintillation spectrometers and the ease of preparing samples for such assay. Difficulties arise, however, in liquid scintillation assay of (A) compounds isolated on paper chromatograms and (B) protein, because it is not easily soluble in most scintillation mixtures. The present report deals with improved methods for liquid scintillation assay of C14-compounds isolated by paper chromatography and of C14-labeled protein.

It is now common to analyze a concentration profile obtained by electrophoresis or gas chromatography using Gaussian distribution properties. The theory of chromatography [1] suggested that a similar type of analysis might also be valid for paper chromatography. The present study indicated the validity of this analytical method in the particular case of paper chromatography, provided that certain precautions are taken [2]. We propose here to point out its essential features.

Determining the type and amount of organophosphate pesticide residue in food products is a complex problem, and one which concerns both the companies which manufacture the pesticides and the Governmental agencies which enforce their proper use.

Rare earth metals, in the range of 0 to 250 micrograms, have been extracted quantitatively from perchloric, nitric or hydrochloric acid solutions by strong acid ion exchange paper disks in the sodium ion form. After the exchange is completed, the ion exchange paper disk is placed in a rotating sample holder and the amount of rare earth metals exchanged is determined by x-ray emission spectrography. At the 10 microgram level, the accuracy has a mean error of 2% with a precision of 1.5% relative standard deviation. The procedure has been applied to Sc+3, Y+3, Ce+4, Pr+3, Nd+3, Sm+3, Eu+3, Gd+3, Tb+3, Dy+3, Ho+3, Er+3, Tm+3, Yb+3 and Lu+3.

If one is faced with the problem of determining the distribution of radioactivity in a paper chromatogram, there are several assay techniques available. The chromatogram may be scanned in a strip counter and the radioactivity estimated by measuring areas under each peak or by use of an electronic integrator [1]. The paper strip can also be cut into appropriate sections and the radioactivity of each section determined under a Geiger counter. Depending on the thickness of the paper, the counting efficiency of these techniques is in the range of 3–10%. More serious than the inefficiency is the variation in efficiency, which makes quantitation difficult.

I should begin by stating that I am very sorry that I could not attend the workshop in which Dr. Morton kindly invited me to participate. As a consequence of my absence I must indicate my appreciation to Drs. Morton and Crow, as organizer and moderator-editor, for asking me to respond to Dr. Moore’s remarks, and especially to express my sincerest thanks to Dr. Moore in sending me a copy of his paper and, subsequently, a copy of his addendum.

The majority of analog recorders utilize either strip charts or circular charts. The strip charts, supplied in rolls, have the great advantage that they can operate continuously for long periods without need of replacement. Circular charts, on the other hand, must be replaced periodically, and hence are used mostly for recording slowly changing variables, a single chart to last, perhaps, one day or one week (Figure 6-1).

Dr. S.R. Caplan (Israel) summarised his work on the self adaptive control of energy conversion and its relation to the mechanical behaviour of muscle.

The availability of oxygen throughout the brain is far from homogeneous, oxygen tensions varying 30 or 40 mm Hg within a distance of a few microns (1–4). However, the pO2 at a given micro-area of cerebral tissue is remarkably constant, and can be changed only through major alterations in blood supply or the composition of respiratory gases (1,4,10). We have defined the different processes arrived at maintaining the constant brain cell oxygen micro-environment as “oxygen autoregulatory mechanisms.”

Mathematics is the only tool available to man that can simultaneously solve the multivariable, interacting problems evolving from physiological systems analysis. The human mind is not capable of thinking in terms of n-dimensional space, therefore forcing us to rely on an organized accounting procedure as provided by applied mathematics.

Adequate understanding of oxygen supply to the microenvironments of the neonatal system is dependent on the ability to make reliable measurements and the ability to accurately interpret the measurements. Experimental measurements in the placenta and fetal system range from overall measurements designed to produce clinical guidelines to detailed microscopic measurements designed to obtain a more basic understanding of fundamental processes. Both the planning and interpretation of measurements vary in scope from intuition based on observation to the beginnings of the mathematics of systems analysis.

An algorithm is presented for determining whether or not two planar graphs are isomorphic. The algorithm requires O(V log V) time, if V is the number of vertices in each graph.

Acrylamide polymers have been available commercially since the early 1950s. The first important applications were as flocculants in the treatment of acid-leached uranium ores and as paper additives to increase dry strength. Numerous other applications have since been developed which can be summarized as follows: Paper Chemicals: dry strength agents, retention aids, drainage aids; Water Treatment: clarification and treatment of municipal and industrial effluents, potable water, foods, etc; Oil Well Stimulation: fracturing, flooding; Mineral Processing: flocculation of ores, tailings, coal, etc; Miscellaneous: friction reduction, thickening, soil stabilization, gel chromatography and electrophoresis, photography, fog dissipation, breaking of oil-in-water emulsions, etc.

The application of microencapsulation technology to pressure sensitive copying systems in modern manifold business forms has grown dramatically in the past few years. It appears that the higher cost and higher waste during forms manufacture with such systems have become less significant factors in curtailing their use than they were formerly. The improved quality and cleanliness of the copy obtained with microcapsule systems as compared with the older hot melt wax (carbon paper) systems is only a partial explanation for their wider use. Short supply of raw materials, preservation of the ecology and waste disposal are now serious considerations limiting the use of the older pressure transfer copying systems. The technical and economic feasibility of recycling carbonless copying papers after use has been demonstrated and this is an additional attractive feature of such systems.

The idea of using a chromatographic adsorbent in the form of a thin layer fixed on an inert rigid support seems to have been suggested by Izmailov and Shraiber in 1938. Meinhard and Hall[1] in 1949 developed this notion of an ‘open column’, and in 1951 Kirchner, Miller, and Keller[2] reported the separation of terpenes on a ‘chromatostrip’, prepared by coating a small glass strip with an adsorbent mixed with starch or plaster of Paris, which acted as a binder. The strips were handled in the same way that paper is handled in paper chromatography, and indeed the original object of the thin-layer technique was to apply the methods of paper partition chromatography to an adsorption system.

With the advent of various types of chromatography, a wide choice of methods is now available for the resolution and isolation of amino acids in complex mixtures. For quantitative analysis, paper chromatography and ion-exchange chromatography are the methods of choice. One-dimensional rather than two-dimensional paper chromatography is preferred as a routine procedure, samples being pretreated with ion-exchange resins to obtain groups of amino acids. Reliable methods for the isolation of the amino acids in the brain after paper chromatography have been published (Gaitonde, 1961; Gaitonde et al., 1965; Robinson and Williams, 1965).

In the treatment of statistical data it is important to distinguish between methods of representation and methods of analysis. Histograms and scatter diagrams, for example, provide means of representing data and are a useful preliminary to analysis; the use of logarithmic graph paper or of one of the many probability papers is similarly beneficial. It is not to be supposed that the mere plotting of points on gaus-sian probability paper constitutes an analysis, or that such a plot is only valid if the points are in fact normally distributed, for the very departure from normality may provide the stimulus for subsequent analysis.

There are a variety of methods for qualitative and quantitative determination of lipoproteins. Electrophoresis has found broad application as a routine method on account of simplicity as compared to ultracentrifu-gation. Thereby, serum lipoproteins are separated into various bands: alpha-, β-, pre-β-lipoproteins and chylomicrons and the relations of these bands to each other are visualized. In addition to the use of agar (URIEL and GRABAR, 1956; PEZOLD, 1957, 1958) and Reinagar (HOUTSMULLER et al., 1964) as supporting medium paper electrophoresis according to JEHCKS and DURRUM (1955) as modified by LEES and HATCH (1963) has been most commonly used, particularly since EREDRICKSON and LEES (1965) have recommended paper electrophoresis for differentiation of hyperlipidemia. Although paper electrophoresis permits demonstration of typical lipoprotein patterns for various types of hyperlipidemias, it is unsatisfactory with regard to the duration of 16 hours, and the frequent occurrence of poor separation particularly for pre-β- and β-lipoproteins.

The papermaking process involves three basic operations. First, a wet web of fibers is formed from a fiber — water slurry and drained on a continuously moving wire. Second, additional water is removed by pressing the web between felts. Third, the web is dried on a series of steam-heated drier drums. The water systems surrounding this basic process will be described in more detail below, as will the complete papermaking system. Figure 1 shows a Fourdrinier paper machine (the most common type), looking from the continuously moving wire toward the driers.

Considerable technological progress has been made in the radioassay of analytical and preparative thin-layer chroma­tography (TLC) plates since Mangold’s original review of this subject (a chapter in Stahl’s book, Dunnschicht-Chromatog­raphic, 62–79, 1962). Although the general approach to radioassay of thin-layer chromatograms is similar to that used in paper chromatography, the two techniques require different radiometric procedures because the physical and chemical nature of the materials used in adsorption TLC are completely different from those encountered in partition separations by paper.

In radiography picture forming involves either fluoroscopy or registration on special photographic film. Images can also be recorded on photographic paper, Polaroid film and paper, and on various color films; however, such applications are exceptional.

Chromatography on thin layers of loose adsorbent was carried out as early as 1938. Ten years later Meinhard and Hall used cohesive films which could be made to stick to a glass plate for chromatographic separations (1). With the introduction of paper chromatographic methods the separation and identification of complex mixtures of amino acids became possible. Following the initial work of Consden, Gordon, and Martin, in 1944 (2), paper chromatography of amino acids developed rapidly. Techniques were devised which permitted semi-quantitative measurement of all amino acids in a complex mixture, whether known or unknown. Development of thin-layer chromatography of amino acids lagged somewhat compared to techniques for separation of lipophilic substances, partly because of the highly satisfactory separations obtained by paper chromatography. However, most of the procedures applicable to paper chromatography were found suitable for use with thin-layer chromatography (TLC).

X-ray fluorescence analysis has been successfully applied to the determination of qualitative and quantitative compositions of very minute amounts of sample. The ratios of major components may be determined unequivocally in microgram amounts. The substance is concentrated in the middle of a filter paper, mylar foil, or a similar carrier. In order to lower the effects of background radiation, small filter paper disks may be used which are just large enough to carry the amount of liquid that is to be analyzed. The filter paper disks are held in the proper position by thin mylar or tape strips which are clamped into the sample holder. The liquid may also be dried directly on a mylar strip. Usually, linear calibration curves result. Qualitative and quantitative analysis of smallest amounts of sample is applied successfully in mineralogy and metallurgy; furthermore, x-ray fluorescence provides a simple and reliable identification of heavy metal-containing compounds in the analysis of paper chromatograms. Properly designed devices make possible aperturing of the primary x-ray radiation to a beam of 100μ in diameter which allows one to scan individual areas in metal and ore sections, as well as in welding and soldering products, point by point. Reference to the literature is made in the following sections.

It is not possible in a short paper to describe the entire fossil fuel technology in any detail. However, for completeness, many of the more commonly used recovery techniques as well as some novel but untested methods are briefly described herein.

Enzymes attached to insoluble supports offer some particularly attractive advantages for many purposes including their use in the food processing industry. These advantages include repeated reuse of the enzyme, ease of removal from the reaction mixture, good or improved enzyme stability and properties which permit use in columns and large continuous reactors. In order to be successful an application must meet these criteria; in addition the costs for the support, the enzyme, the process for attachment, the equipment, and the operating costs must all be low. Previously we have reported on the use of phenol-formaldehyde resins as supports for immobilizing enzymes (1). This paper presents some of the most recent findings with this method of immobilization from pilot scale runs using a β-galactosidase from Aspergillus niger as the model enzyme for the hydrolysis of lactose in milk, whey, and deproteinized whey. Some examples of the variations possible with this method of enzyme immobilization are also discussed.

The heterogeneity of lactate dehydrogenase was first recognized when Neilands (1952) demonstrated activity in each of the two electrophoretically distinct proteins, previously separated by Meister (1950) from the crystalline ox-heart enzyme. Subsequently Vesell and Bearn (1957) found three distinct components when human sera were subjected to starch-block electrophoresis, and Sayre and Hill (1957) obtained similar results with paper electrophoresis and gradient-elution chromatography. About the same time Wieland and Pfleiderer (1957) found that most organs contain up to five protein fractions each exhibiting lactate dehydrogenase activity. Soon afterwards it was appreciated that the isoenzyme composition of the serum was of considerable diagnostic value (Vesell and Beam, 1958a, 1958b; Hess, 1958; Wieme, 1959), and this gave a tremendous impetus to further study of variations in the isoenzyme content of the blood serum.

The form in which acids are present in the analyzed material is important to the analyst: whether they are free, in aqueous solution, in the form of salts or solutions of these salts, or mixed with other neutral or acid substances. The character of the sample determines the course of the analytical procedure. It is also important to bear in mind that some carboxylic acids are volatile (lower aliphatic monocarboxylic acids), some are volatilized by steam distillation (monocarboxylic acids), others are water soluble (lower monocarboxylic and certain dicarboxylic acids), and practically all are soluble in 5% sodium hydrogen carbonate. All these properties offer a possibility of separating these substances from others. As carboxylic acids do not give characteristic color reactions, all general detections of this class of substance are based on their acidity. This is determined in aqueous solutions by means of indicators, and in the case of water-insoluble acids on the basis of their solubility in 5% sodium hydrogen carbonate. In all instances, however, it is advisable to complete the proof of acidity by titration with alkali; in the case of pure acids by determining their NE (neutralization equivalent), which is characteristic for each acid. In the case of more complicated mixtures titration affords information on the approximate amount of acids present in the sample and whether they represent a substantial fraction of it. If acidity is found in the sample, it is also necessary to look for the presence of sulfur, because the acidity could be caused by the presence of sulfonic acids. However, as the detection of acidity need not be reliable in more complicated cases, it is much safer to employ paper chromatography and to carry out the acidity detection on the chromatogram. This method has the advantage that it can also be carried out with salts.

X-ray fluorescence techniques combined with very simple procedures of sample preparation such as drying of a few droplets of liquid on filter paper allow measurement of calcium, potassium, chlorine, sulfur, and phosphorus in blood serum and in cell fluids. X-ray fluorescence is often more accurate and considerably faster than other analytical techniques. The hemoglobin contents of the blood may be determined by measuring the fluorescent intensity of the associated iron in the hemoglobin. In the case of toxicologic tests, the bromine content of blood serum, urine, and of cells or spine fluids may be determined reliably. Ashes of tissue, serum, and bones may be tested for heavy elements such as iron, zinc, copper, and strontium, and the calcium-strontium ratio may be determined. X-ray fluorescence further allows one to determine the sulfur content in electrophoretically separated protein fractions of the serum and to detect pathologic changes. X-ray fluorescence analysis further allows the determination of contents of specific and biologically effective substances as long as they are associated with a heavy metal. Examples for these determinations are cobalt-containing vitamin B12, iodine-containing hormones, or zinc-containing substances.

During the past few years several methods have been developed for the measurement of plasma testosterone. Finkelstein et al. (1) reported a method based on the enzymatic conversion to estradiol of testosterone isolated by paper chromatography. The estradiol was estimated by fluorometry. Double isotope derivative techniques using either H-acetic anhydride (2) or S-thiosemicarbazide (3) have been described. Although remarkable in their sensitivity and reproducibility, these methods are extremely complicated and expensive.

Polarization studies with the Cary Model 14 spectrophotometer required the differences in absorbance units of the E vector in the vertical and horizontal positions for polarizing sheets as a function of wavelength. This presented no problem for the Cary Model 14R since it was equipped with a Datex system for converting spectral traces to digital data and recording on punched paper tape. Measurements of other Gary 14 instruments, not modified to accommodate the digital system, involve a laborious point-by-point treatment of the data to obtain these differences. This communication describes a simplified technique, applied to the Cary 14R-Datex system, to digitize spectral traces from other Cary 14 instruments. This procedure provides not only the differences in absorbance units for polarization studies but also file data of other spectra for reference uses.

X-ray diffraction is the most powerful tool available for the determination of the phase composition of multicomponent crystalline mixtures. In order to take advantage of the great potential of digital computers for aiding quantitative X-ray diffraction analysis (QXDA), equipment has been set up to obtain X-ray diffraction data directly in digital form on punched paper tape. The method of using a computer to produce a quantitative analysis from the recorded data is described and results obtained for the analysis of Portland cements are used as an illustration.

Germicidal and fungicidal chemicals are currently being added to paper, textiles, upholstering substances, paint, plastics, rubber, cement, waxes, and other materials with certain professed objectives. These might be listed as follows: 1. The preservation of the material itself and articles made therefrom from direct and indirect attack by bacteria and fungi. 2. Odor proofing materials and articles made therefrom by preventing the growth of bacteria and fungi on or in the material and/or commonly associated soils such as perspiration in the case of wearing apparel or moisture condensates on surfaces in humid areas. 3. The provision of a measure of protection to perishable commodities from microbial contaminants carried by environmental surfaces which might subsequently cause deterioration and spoilage. 4. The provision of a measure of health protection to man or other living animals through control of infectious bacteria and fungi carried by inanimate materials or articles fabricated therefrom. 5. The prevention of the production of body irritants and/or nuisances other than objectionable odors by suppressing the growth of bacteria and fungi on or in the material or its associated soils.

Low-pressure ultrafiltration is still in the preliminary stages of development as a unit process in municipal waste and wastewater treatment. Recently, the membrane process of reverse osmosis, developed initially for use in desalination, has attracted attention as a promising method for treatment of wastewaters. Data on the separation or removal of pure organic solutes is needed to evaluate the potential application of ultrafiltration systems in wastewater treatment. The organic solutes in wastewater streams cannot, in general, be economically recovered by chemical means. Ultrafiltration has the potential of making possible the economic treatment of at least some industrial wastewaters. A pertinent example is the pulp and paper industry, in particular, research efforts now being conducted by the Pulp Manufacturers Research League.(1,2,3) studies carried out on reverse-osmosis treatment of secondary-sewage plant effluent at Pomona, California(4), have demonstrated the feasibility of reverse osmosis for treatment of complex wastewaters containing relatively high concentrations of organic pollutants.

Traditionally, the teaching of biology has been characterized by abrupt discontinuities with one branch of the subject largely isolated from another; thus botany has been distinct from zoology intellectually and sometimes in geographical location as well. During recent years welcome changes have been initiated in the direction of a more interdisciplinary approach, beginning in the schools under the influence of the Nuffield Projects and spreading more slowly within the universities. In the midst of these changes in biological thought and attitudes, one of the great unifying themes has been heredity. It is a great pleasure to contribute this short paper in honour of Professor Ford, since it provides me with an opportunity to pay tribute to him on behalf of the many students of biology both at Oxford and elsewhere, who have been stimulated and inspired by his teaching of genetics, particularly that aspect of the subject which has become so peculiarly his own—ecological genetics.

In our rheumatism research unit we are interested in the excretion of unconjugated corticosteroid metabolites because they may provide some evidence of the extra-hepatic metabolism of corticosteroids. A method was developed for estimating Cortisol metabolites in urine (1) which involved a preliminary separation of the extract by paper chromatography (Bush B5 system) and, after bismuthate oxidation, determination by GLC on a neopentyl glycol adipate column. This communication describes an improvement on the method and involves the following procedure.

Liquid chromatography has an impressive history, stretching back into the 19th century, which has been well documented elsewhere(1). As an indispensable technique for the separation and analysis of organic substances it has made enormous strides in the past decade or so. Prior to 1958 column chromatography was conducted with comparatively large samples separated in, often short, almost invariably wide-bore, columns through which the developing liquid percolated under gravity. Thin-layer techniques were unknown outside a small group of workers(2), although paper chromatography was widely practiced.

At the present time, seismological and many other geophysical processes are recorded mainly by the action of light on a photographic paper or plate, using a mirror galvanometer driven by the emf from a seismograph or other transducer. This method gives accurate and detailed records, even of weak processes. Its main defect is the large, unproductive expenditure of photographic materials.