Amersham

Radioactive tracers account for about 20% of the worldwide market for consumables and reagents for life science research. In 1994 the value was estimated at about 300 million. The principal fuU line manufacturers are Du Pont—NEN Research Products (Boston, Massachusetts) and Amersham International (Amersham, U.K.). These companies share roughly equaHy about 85% of the radiochemicals worldwide market. In addition to an extensive line of catalog products, these suppHers offer custom labeling and custom synthesis services. The rest of the market is shared by producers of a limited range of products or services, such as ICN Biomedicals (Costa Mesa, California) and American Radiolabeled Chemicals (St. Louis, Missouri). 

Guide to the Self-decomposition ofRaidiochemicals, Amersham International pic, Amersham, U.K., 1992. 

Radiopharmaceuticals may be sold either direcdy or through nuclear pharmacies. These entities, some of which are owned by manufacturers, provide radiopharmaceuticals in unit dose form. In the United States, both MaUinckrodt and Amersham own nuclear pharmacies in many cities. In addition the market is also served by Syncor, an independent nuclear pharmacy that has a nonexclusive strategic aUiance with Du Pont Pharma. 

Plus One REPEL-SILANE ES (a solution of 2% w/v of dichloromethyl silane in octamethyl cyclooctasilane) is used to inhibit the sticking of polyacrylamide gels, agarose gels and nucleic acids to glass surfaces and is available commercially (Amersham Biosciences). 

FIGURE 2.1 SEC analysis of a polymeric dextran sample (Mw = 1000) on Superdex peptide HR 10/50. The very high resolution between individual components of the sample is obtained by using two columns in series. Courtesy of T. Andersson. (Reproduced with permission from Amersham Pharmacia Biotech.)... 

FIGURE 2.3 Selectivity curves of various modem SEC media. (I) Superdex peptide, (2) Superdex 7S, (3) Superdex 200, (4) Superose 12. (S) Superose 6, (6) Sephacryl S-lOO HR. (7) Sephacryl S-200 HR, (8) Sephacryl S-300 HR, and (9) Sephacryl S-400 HR. (Reproduced with permission of Amersham Pharmacia Biotech.)... 

FIGURE 2.9 Industrial fractionation by SEC using Sephacryl S-lOO in three BPSS columns (L = 30 cm, i.d. = 140 cm) to give a total bed volume of 1500 liters. Courtesy of R. Hersberg. (Reproduced by permission of Amersham Pharmacia Biotech.)... 

Four column systems are available from Amersham Pharmacia Biotech that can be used to pack SEC media for various applications at the laboratory scale. These include C, XK, SR, and HR column systems. All of the laboratory-scale columns are constructed with borosilicate glass tubes. Columns for larger scale process applications include INdEX, BPG, EineLINE, BPSS, and Stack columns. The larger scale columns are constructed to meet stringent validation requirements for the production of biopharmaceuticals. Each of the column types are described. 

Sephadex, Sepharose, Sephacryl, Superose, Superdex, FPLC, SMART, HiTrap, HiPrep, and INdEX are trademarks owned by Amersham Pharmacia Biotech AB. 

Hyde AW, Amersham N. The changing face of electronic data capture from remote data entry to direct data capture. Drug Inform J 1998 32 1089-1092 0092-8615/98. 

Materials. I-EGF was either made by iodinating mouse EGF (Biomedical Technologies Inc.) by the chloramine T method, to a specific activity of approximately 1-2 Ci/ xmol, using Na- I (Amersham) or purchased from New England Nuclear. Phorbol diterpene esters were purchased from Sigma. Palytoxin was isolated from Palythoa tuberculosa as previously described (1). 

The amplification products were electrophoresed on agarose gels. Blots were performed according to protocols supplied with Hybond - N-nylon membrane (Amersham). 

The specifications and standardization include raw materials, preparation method of the standard solution, concentration of proteins, and the main band on SDS-PAGE. The outline of the procedure for preparation of the calibrators is shovm in Eig. 4.2. Table 4.5 shows the raw materials and the preparation method of the initial extract. To prepare the calibrators, the raw materials are extracted by the standard solution containing SDS and mercaptoethanol. The initial extract is prepared by centrifugation and filtration of the extract. The diluted extract is then prepared by 10-fold dilution of the initial extract with phosphate-buffered saline (PBS pH 7.4). The protein concentration of the diluted extract is assayed using the 2-D Quant kit (Amersham Bio Sciences). The standard solution is then... 

The protein content of the initial extract was determined using the 2-D Quant kit (Amersham Bio Sciences). The initial extract was diluted 20 times to make up the calibration standard solution. 

Amersham International Limited, Technical Catalog RS16-8, Mossbauer Sources (1981)... 

The diabetic rats were treated with 18 IU of bovine insulin imbibed into polyacid resins b.i.d. orally using 1 cc syringes and gavage tubes. After 14 days of treatment the rats were sacrificed about 1.5 hours after the last dose. Blood samples were taken and assayed for immunoactive insulin activity (Amersham-Searie RIA kit) and serum glucose levels (glucose oxidase colorimetric assay, Sigma 510 Glucose Kit). 

Second, the technology has mediocre reproducibility. Software is available to morph images so that spots can be lined up such software is expensive, difficult to use, and not always accurate in its alignment. To overcome this problem and to simplify quantitative comparisons between samples, Unlu et al. (1997) developed differential gel electrophoresis (DIGE), where two samples are each labeled with different fluorescent tags, pooled, separated on the same gel, and scanned at characteristic wavelengths to resolve the components. This technology has been commercialized by Amersham. 

MegaBACE is commercially available from Amersham Pharmacia Biotech (Freiburg, Germany). 

Immunodetection is performed by chemiluminescence (ECL , Amersham Pharmacia Biotech) using horseradish peroxidase-conjugated secondary antibodies (Amersham Pharmacia Biotech). 

Approximately 1 mg of total protein is pre-incubated with 25 /il of A-Sepharose beads CL-4B (Amersham Pharmacia Biotech) in 300 /d of binding buffer FLA for 1 h at 4° with gende rocking. The sample is then spun down at 1000 rpm for 3 min in an Eppendorf F 45-24-11 rotor, preserving the supernatant for further use. An aliquot of 3% of the total protein from each reaction is stored at —20° to provide the input reference sample in the subsequent analysis. 

Anion exchange chromatography The reaction mixture is subjected to phenol/chloroform extraction to remove the T7 RNA polymerase using phenol equilibrated with 50 mM Na acetate (pH 4.5). After isopropanol precipitation, the pellets are resuspended in 20 mM MOPS buffer (pH 6.25) containing 350 mM NaCl. The excess unincorporated NTPs and the smaller abortive transcription products are removed by chromatography on anion exchange FPLC column (MonoQ 5/5 column, Amersham). 

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