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A method for the on-line absorptiometric determination of trace amounts of boron in steels was developed using an anion-exchange column presorbed with chromotropic acid. The on-line reaction and separation were achieved by controlling the pH in order to accelerate the complex formation in the column by 2.7 and to stabilize the complex at pH 8 for the selective elution of a 1:2 complex and its detection at 350 nm. The effects from the iron matrix in the sample were effectively removed by using EDTA as a masking agent; a low limit for boron detection (3σ) of 0.04 µg g(-1) was obtained.

A comprehensive radiochemical procedure for the measurement of gamma/beta activity of131I has been standarized by optimizing different steps. The procedure is mainly divided into three stages, i.e., (1) concentration of iodine using anion exchange column followed by elution; (2) extraction of iodine into CCl4 and back extraction, and (3) precipitation as AgI. The percent chemical recovery and the lower limit of detection (LLD) were found to be 75.5±5% and 0.014 mBq/ml, respectively.

Plant material contains carbohydrates and phenolic compounds that interfere with derivatization and HPLC analysis of polyamines. The use of strong anion-exchange resins was investigated for purification of polyamines in plant samples. Results obtained indicate that anion-exchange resins produce equally good results as cation-exchange resins. Polyamines are eluted from the anion-exchange resin with NaOH, and derivatization can be performed directly on the eluate, resulting in enormous time savings. Optimum results were achieved with low cross-linkage strong anion-exchange resins and the conditions for maximum recoveries of polyamines are reported.

The anion exchange behavior of 255No produced by the 248Cm(12C,5n) reaction has been investigated in 11.5M HCl, 4M HCl and 8M HNO3 to deduce the behavior of 'primordial 257No' produced via 248Cm(18O,5n)261Rf →α 257No before anion exchange separation in the 261Rf experiment. It was found that 255No is mostly eluted from the anion exchange column with these solutions. The contribution of 'primordial 257No' to the α-decay events of 261Rf in the 261Rf experiment was evaluated based on the present results.

An HPLC technique using a PROTEIN PAK DEAE-15 HR anion exchange column was developed for the isolation of electrophoretically pure κ-casein, β-casein, α s2 -casein and α s1 -casein from 250 mg of whole casein. A 20 m m TRIS buffer in 4·5 m urea at pH 7·0 and a convex NaCl gradient from 0 to 0·15 m , followed by a concave NaCl gradient from 0·15 to 0·4 m provided the optimum conditions for separation of the casein components. The actual separation time of the four major caseins was less than 1 h. After allowing time for column regeneration and equilibration, whole casein samples for separation could be loaded into the system every 2 h. Quantitative measurements of the eluted fractions correlated well with known literature values and all the casein components were accounted for.

陽イオン交換カラム (ICS-C25)と陰イオン交換カラム(ICS-A23)を直列に接続した系における陽イオンの溶離挙動とその溶離機構について検討した.陽イオンのクロマトグラムは陰及び陽イオン交換カラムの接続順序によって異なる.陽イオンは陽イオン交換樹脂から移動相に溶出するとき,溶離液の有機酸陰イオンとイオン対又は錯体を形成して有機酸陰イオンの濃度を減少させる.陽イオン交換カラムからの溶出物は後に接続した陰イオン交換カラムに入ると,有機酸陰イオンはイオン交換又は疎水性分配相互作用により陰イオン交換樹脂に保持される.従って,移動相中の有機酸陰イオンの濃度の減少に由来する寄与分のピークは本来の陽イオンピークより遅れて現れる.酒石酸(TA)と2,6-ピリジンジカルボン酸(PDC) の混合溶液を溶離液に用いる場合には,陰イオン交換カラム中での2種類の有機酸陰イオンの保持時間が異なるため, 1 種類の陽イオンに対して3本のピークが現れる.つまり,一次ピークは陽イオンの溶出及び移動相中の溶離イオン (H+) の減少に由来するものであり,二次と三次ピークはそれぞれ移動相中のTAとPDC陰イオンの減少に対応するものである.これらのピークはピーク面積の比較及びサプレッサーの有無により確認した.

A simple, rapid method has been developed for the sequential separation of actinide elements from samples with high salt content such as those resulting from efforts to characterize Hanford storage tank waste. Actinides in 9M HCl solution are introduced into an anion exchange column. U(VI), Np(IV) and Pu(IV) are retained on the column while Am(III) passes through. Plutonium is eluted first, reductively; after which neptunium and then uranium are eluted with mixtures of HCl and HF. The Am(III) is purified by cation exchange in a nitric acid system.

Alpha emitting radionuclides are of considerable interest for targeted radioimmunotherapy. Generator supplied 213Bi emitting 8.5 MeV alpha particles with a 45.6 min half-life has been conjugated to a monoclonal antibody (HuM195-CHX-A-DTPA) for targeted therapy of leukemia in a clinical trial. The clinical dose preparation of pharmaceutical formulation by a pair of skilled radiochemists took 25 min, which corresponds, to an overall decay loss of 30% of the initial 213Bi activity eluted from the generator. In order to allow more widespread and practical clinical use of targeted 213Bi alpha particle therapy, we developed a new procedure that is simpler, more rapid and adaptable to a hospital pharmacy. The new 10 min process includes a tandem elution and labeling, and an anion exchange column purification method that can be reproducibly used.

Publisher Summary This chapter explores the applications of tandem capillary high-performance liquid chromatography in the isolation of proteins for characterization using microsequencing and mass spectrometry. It highlights the resolution and sensitivity of the Polywax LP anion exchange column. In a study described in the chapter, three protein samples in the 10 pmole range were separated with baseline resolution. The volume of the fractions was in the 20–30 μL range. The carbonic anhydrase eluted prior to the start of the salt gradient at 5 min after injection. AU three fractions showed good peak symmetry, though a slight amount of tailing was exhibited by the α-lactalbumin. The series of small peaks eluting between conalbumin, and alactalbumin were a contarninant present in the conalbumin sample purchased from Sigma. The chapter highlights the resolution and sensitivity of the Polycat A cation exchange column. Four protein samples in the 15 pmole range were separated with baseline resolution. The volume of the fractions was in the 20–35 μL range. AU four fractions showed good peak symmetry.

A rapid, reproducible and sensitive high performance liquid chromatography (HPLC) method for the determination and purification of metallothionein-I (MT-I) and metallothionein-II (MT-II) in mouse and rabbit livers has been developed. Methallothioneins (MTs) were separated by an HPLC anion exchange column, eluted through a linear gradient of Tris buffer and the peak containing MTs was determined by atomic absorption spectrophotometry. Furthermore, the content of MT-I or MT-II was calculated by protein peak area in a short time (about 20 min). The sample to be tested was homogenized, centrifuged and saturated by cadmium. MT-I and MT-II were eluted at 15.9 and 19.3 min, respectively. The following mouse liver cytosols were tested: controls, Cd-injected samples and 60Co-irradiated samples. A detection limit of 5 micrograms/g liver was established for this method. We have analysed more than 100 biological samples and obtained satisfactory results.

In this paper, the authors demonstrate the determination of malate enantiomers by using a hydrophilic material-based anion exchange column and chiral copper(II)-tartrate complex as an eluent

The concentrations of D-glucose and D-galactose in plasma of galactosemic rats were quantitatively measured by a liquid chromatographic method, based on retention of the weakly ionized monosaccharides by an anion exchange column under alkaline conditions, elution with 9 mmol/L NaOH, and electrochemical detection. This method is both simple and sensitive, since very dilute plasma samples can be directly analysed.

The Pharmacia Fast Protein Liquid Chromatography System equiped with a Mono P HR 5/10 chromatofocusing column was used to characterize the distribution of different bioactive forms of a cynomolgus (Macaca bascicularis) pituitary lutropin preparation. The results were compared with the profiles obtained after running the preparation on a Waters DEAE anion exchange column using eluants in the pH range from 6.0 to 8.0. The distribution of preserved biological activity were studied in respective eluted fractions from the different experiments of the applied preparation. Seventy-six percent of the bioactivity was recovered after chromatofocusing whereas preserved bioactivity after ion exchange chromatography ranged between 61–78% at pH 6.5 to 7.5. No bioactivity was restored after elution at pH 6.0 or 8.0.

The separation of large, single-stranded oligodeoxyribonucleotides, prepared by chemical synthesis, was carried out on a DEAE-5PW anion-exchange column with eluents containing only volatile salts. It was found that gradient elution is essential and that a high resolution can be achieved at elevated temperatures ( ca. 50°C). Also, neutral pH of the eluents was found to be desirable for the separation. Under optimum conditions, a linear relationship between the elution volumes and the number of bases in the substrates was observed.

High performance ion exchange chromatography using aqueous solvents is presented for the separation of proteins. Diethylaminoethyl(DEAE) resin for the anion exchange column and sulfopropyl(SP) resin for the cation exchange column were utilized. Proteins, having a molecular weight of 10000 - 190000 daltons and an isoelectric point of 3.9-10.7, were separated within 60 min by sodium chloride linear gradient elution. The protein was eluted according to its isoelectric point. These columns are capable of separating proteins with the biological activity in high speed, high resolution, large capacity and considerably high recovery.

A separation procedure is described for the continuous, carrierfree removal of the daughter product /sup 231/Th(T = 25.6 h) from a sample of /sup 235/ U held on a specially designed, flat anion exchange column. Thorium-free uranium prepared by this ion exchange method showed no activity in the 0 to 300 keV region other than /sup 235/U and the /sup 235/U can be maintained free of /sup 231/Th for several weeks by continuous elution at the rate of 4 drops a minute. (DHM)

The quantitative analysis of 2-keto- l -gulonic acid (2-KLG) produced by microbial fermentation is described. 2-KLG is separated from other aldonic and ketoaldonic acids by high-performance liquid chromatography on an Aminex anion exchange column with ammonium formate or potassium phosphate as the eluant. This is a rapid and simple method for routine analysis of a large number of samples generated by fermentation studies. Gas chromatography—mass spectrometry permits the qualitative and quantitative analysis of nanogram levels of 2-keto- l -gulonate in complex media and provides confirmation of the HPLC results. The methodologies presented are useful for the analysis of a number of aldonic and ketoaldonic acids.

A procedure is described to separate mercury from, mammalian tissues so that a previously devised photometric method of analysis for submicrogram amounts of mercury can be used with precision for such samples. Mercury is first separated from tissue by a cold digestion in hydrochloric acid-sodium nitrate; it is then collected on an anion exchange column and eluted with thiourea solution. Finally it is collected in cadmium sulfide, volatilized at 550° C., and determined photometrically by using a General Electric germicidal ultraviolet intensity meter. Results of analyses of rat and mouse tissues are presented, and the usefulness of the procedure for industrial hygiene is discussed.

This paper describes a method of estimating the nucleotides in red blood cells. The technique used is based on that of Cohn and Carter (1950), who have shown that the nucleotides, adenosinemonophosphate (A.M.P.), adenosinediphosphate (A.D.P.), and adenosinetriphosphate (A.T.P.) can be separated by an anion exchange column. Bartlett, Savage, Hughes, and Marlow (1953) have successfully used this method for estimations on 100 ml. of whole blood; however, this volume is inconveniently large, especially if serial estimates are to be carried out. The present method uses only 1 ml. of red cells. Quantitative measurements have been made using the characteristic ultra-violet light absorption of adenine. In order to reduce the quantity of other substances also absorbing ultra-violet light, preliminary precipitation of the nucleotides as barium salts is carried out before placing them on the column. After elution of the nucleotides in separate fractions, the ultra-violet light absorption at three wavelengths is measured and correction for impurities made by the method of Morton and Stubbs (1946). This paper contains a detailed account of the method and findings of the nucleotide content of fresh red cells from 12 normal subjects. In order to demonstrate the use of the method, the results obtained before and after incubating stored red cells with adenosine are described.

A method for determining thorium and uranium at the sub-microgram level (down to 10−3 μg) is described. Bone which has previously been ashed at 600°C is irradiated in a neutron flux of 2 × 1013 cm−2 sec−1 for 20 min. After chemical separation which involves elution from an anion exchange column using a mixture of hydrochloric and hydrofluoric acids, the induced Pa223 and Np239 activities were measured and compared to a standard. The method was tested using samples of ashed cow bone to which were added known concentrations of uranium and thorium and results for the analysis of several bones with widely differing histories are presented.

A simple method was developed for the separation of carrier-free 125 Sb from neutron-irradiated tin. The irradiated tin was dissolved in 12 M HCl and diluted with water. Bromine was added to oxidize Sn(II) to Sn(IV) and Sb(III) to Sb(V). The resulting solution was passed through an anion exchange column. All of the tin remained on the resin, and the eluate from the column contained carrier-free 125 Sb.

An anion-exchange column system is described which is capable of separating ethylenediaminetetraacetic acid (EDTA) from diethylenetriaminepentaacetic acid (DTPA) in the form of their calcium chelates. In addition, distinct elution positions are demonstrated for: (1) the unchelated form of DTPA; (2) the calcium chelate of DTPA; and (3) the plutonium(IV) chelate of DTPA. Preparation and chromatograhy of a doubly labeled complex of /sup 239/Pu(IV) and /sup 14/C-labeled DTPA ((/sup 14/C)DTPA) are also described. Separation of (/sup 14/C)DTPA from autoradiolytic breakdown products found in high-specific-activity preparations is demonstrated. This chromatograhic procedure has the potential for use in studying the metabolism and mechanism of action of DTPA and for evaluating the purity of (/sup 14/C)DTPA preparations.