Hunter procedures

The following procedure describes the iodination process for the Bolton-Hunter reagent and its subsequent use for the radiolabeling of protein molecules. Modification of other macromolecules can be done using the same general method. For particular labeling applications, optimization of the level of iodine incorporation may have to be done to obtain the best specific radioactivity with retention of biological activity. 

In 1937 Hunter and Hlynka were able to reduce a methanolic solution of 4(5)-nitroimidazole (27 R = H) with sodium amalgam and trap the 4(5)-aminoimidazole (25 R = H) with cyanic acid giving the urea derivative (31) (37BJ488). Other reducing agents gave inferior results. Subsequently, 4(5)-aminoimidazole (25 R = H) was obtained as either its dihydrochloride (30%) or dipicrate salt but the isolation procedures were lengthy and difficult (41 Mil). 

Hunig s Base, 2 549t Hunter Color Spaces, 7 321 Hunter-Nash procedure, 10 757 Huntsman fixed-bed maleic anhydride process, 15 501... 

Analytical Methods. The samples were analyzed by standard AACC (21) procedures for moisture (air-oven method), protein (Method 46-13), crude fat (Method 30-25), crude fiber (Method 32-10), insoluble dietary fiber (Method 32-20) and ash (600°C, 3 hr). Starch content was determined by the polarimeter method (Method 76-20) and total sugars by Method 80-60. Color characteristics of the dried products were evaluated with the Hunter Color Difference Meter. 

The development of an adequate mathematical model representing a physical or chemical system is the object of a considerable effort in research and development activities. A technique has been formalized by Box and Hunter (B14) whereby the functional form of reaction-rate models may be exploited to lead the experimenter to an adequate representation of a given set of kinetic data. The procedure utilizes an analysis of the residuals of a diagnostic parameter to lead to an adequate model with a minimum number of parameters. The procedure is used in the building of a model representing the data rather than the postulation of a large number of possible models and the subsequent selection of one of these, as has been considered earlier. That is, the residual analysis of intrinsic parameters, such as Cx and C2, will not only indicate the inadequacy of a proposed model (if it exists) but also will indicate how the model might be modified to yield a more satisfactory theoretical model. 

A. Dijkstra, and L. Kaufman, Evaluation and Optimization of Laboratory Methods and Analytical Procedures (Amsterdam Elsevier, 1978) G. E. P. Box, W. G. Hunter, and J. S. Hunter, Statistics for Experimenters An Introduction to Design Data Analysis and Model Building (New York Wiley, 1978) R. S. Strange, Introduction to Experimental Design for Chemists, J. Chem. Ed. 1990,67. 113. 

An excellent review on experimental design which is followed by a valuable discussion of numerous scientific and educational aspects is given by STEINBERG and HUNTER [1984], In analytical chemistry experimental design has been used to optimize almost all types of analytical procedure because of its ease of use. 

There are many alternatives for modeling high pressure phase equilibria. Therefore, it is required a discrimination procedure capable to screen these models satisfactorily. In this work we have compared two discrimination methods in order to select the next experimental point. The first one is the Hunter-Reiner methodology that considers only the predicted response of each model according to the following equations ... 

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the workshop summary nor did they see the final draft of the workshop summary before its release. The review of this workshop summary was overseen by Jennie Hunter-Cevera, University of Maryland, Rockville. Appointed by the National Research Council, she was responsible for making certain that an independent examination of this workshop summary was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this workshop summary rests entirely with the authors and the institution. 

Quaternary Ammonium Herbicides Paraquat and diquat are the most important members of this class and are readily available in various proprietary formulations. Their analysis is complicated by the fact that they are not extractable by conventional liquid/liquid extraction procedures, nor can they be gas chromatographed in their original form. Ingestion of large amounts (several grams) of paraquat leads rapidly to death, and in these cases ultraviolet spectrophotometry may be used. However, death can occur even with smaller doses (300 mg), and the concentrations in body fluids are consequently much lower. Specific radioimmunoassay methods have been developed (T. Levitt, Proc. Analyt Div. Chem. Soc., 1979, 16, 72-76, and D. Fatori and W. M. Hunter, Clinica chim. Acta, 1980, 100, 81-90). 

Design of Experiments Construction of efficient test patterns for these activities. Factorial designs are well treated by Box, Hunter, and Hunter (1978). Sequential procedures for experimental design are presented in Chapters 6 and 7 and Appendix C, and in the references cited there. 

The introduction of I into molecules containing tyrosyl or histidyl moieties can be carried out chemically by the Chloramine T procedure or enzymatically by lactoperoxidase." The prelabeled Bolton-Hunter reagent [A-succinimidyl 3-(4-hydroxyl-5-[ I]iodophenylpropionate] reacts under mild conditions with molecules containing amino groups (e.g., proteins and haptens) to introduce an iodinated propyltyrosyl moi-... 

Procedure. In a small glass vial, add the Na I solution at room temperature to crystalline SHPP. Immediately add sodium metabisulfite to reduce the oxidizing agent and iodide, stopping the reaction. Carrier KI is added and the iodinated ester ( I-labeled Bolton-Hunter reagent) isolated by addition of DMF (5 pX) followed by extraction with two portions of reagent grade benzene. To prevent hydrolysis (i.e., inactivation) of the labeled ester, the entire procedure must be carried out as quickly as possible (<1 min). 

The following procedure, taken from the original paper by Bolton and Hunter, describes the labeling of human growth hormone (HGH). 

Buffer 50 mM sodium borate, pH 9.5 Procedure. Add the albumin to the I-labeled benzimidate in a total volume of 1.0 ml of buffer maintained at 37°. After 24 hr the product is isolated by dialysis against 0.15 M NaCl containing 5 mM sodium phosphate, pH 7.4. Presumably, separation could be effected be gel filtration as described above for isolation of the product labeled with the Bolton-Hunter reagent. Under these conditions (14 1 molar ratio of I-benzimi-date to albumin), maximum incorporation of was 30%. 

Alternatively, the Bolton-Hunter reagent can be used to prepare [i2 i]pa,7 xhis is the method of choice. The procedure is simple, and re-... 

This is essentially the chloramine-T procedure first described by Greenwood, Hunter and Glover, and the aim is to label 1 mol of anti-IgE with 1 atom of I. 

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