General Laboratory Procedures

Dehydrogenation of alkylbenzenes although useful m the industrial preparation of styrene is not a general procedure and is not well suited to the laboratory prepara tion of alkenylbenzenes In such cases an alkylbenzene is subjected to benzylic bromi nation (Section 11 12) and the resulting benzylic bromide is treated with base to effect dehydrohalogenation... 

In the laboratory, a solution of known concentration is often prepared in a glass vessel called a volumetric flask. Volumetric flasks typically allow volumes to be measured with an accuracy of four significant figures. Figure 3-17 summarizes the general procedure for making a solution in a volumetric flask. This procedure is further described in Example 3-17. 

A general procedure that our laboratory generally employs is the addition of an equal amount of methanolic 10% potassium hydroxyde (KOH) to an ethereal carotenoid extract. This solution is bubbled with N2 and allowed to stand overnight at room temperature. Other conditions that shorten time at room temperature have also been used, such as saponification of the dichloromethane (CH2CI2) extract with the same amount of 10% KOH in MeOH for 1 hr (peppers and fruits ) and ethereal extract treated with 30% methanolic KOH under N2 for 3 hr (green leaves, vegetables and fruits ). 

Data from this laboratory and others8,9,10 indicate that the general procedure outlined for the synthesis of F2PX compounds may be extended to the synthesis of the oxy derivatives of pentavalent phosphorus such as F2C1P0 and Cl2FPO, but the detailed directions are not given here. The mixed oxyhalides of phosphorus, like the corresponding mixed halophosphines, have not been obtained easily in pure form from complex reaction mixtures.11,12... 

Quality control describes the measures used to ensure the quality of individual results or a batch of results. The measures used will vary according to the particular application. It is a means of evaluating the current performance of the method being used and the general procedures used in the laboratory. There are two types of quality control, namely internal quality control and external quality assessment. These are covered in detail in Chapters 6 and 7, respectively. 

The Zymark robotic laboratory automation system Although detail procedures differ in each laboratory, the basic elements of binding and enzyme assays are similar. The generalized procedure shown in Table 1.10 highlights the common steps and indicates which Zymate laboratory systems are required. These procedures are performed using common laboratory glassware such as test tubes or in multiple tube devices such as microtitre plates. 

This is enough to give you the general procedures to extract any of the over the counter drugs that you may run into. If you are still hopelessly confused, then you really are not educated enough in the chemistry field to be working in a laboratory. 

The hydrolysis of a hindered amide can often be difficult. V. Bavetsias of the Cancer Research UK Laboratory in Surrey reports (Tetrahedron Lett. 2004, 45, 5643) that mcthanolic Fe(NO,),9H,0 will smoothly hydrolyze pivalamides such as 1 at room temperature. If this proves to be a general procedure for hindered amides, it will be a welcome addition to the armamentarium of organic synthesis. 

In this chapter, the analysis of leukocytes, one of the more important applications of flow cytometry, is discussed. It is an important application not because leukocytes are intrinsically more important than other types of cells but because they constitute a class of particles that, for several reasons, are ideally suited for analysis by flow cytometry and thus make very good use of the capabilities of the technique. Leukocytes therefore account for a large proportion of the material analyzed by flow cytometry in both hospital and research laboratories. They also serve as good examples for describing here some of the general procedures of cytometric protocol, particularly the art of gating and the requirements for controls. 

Such a general procedure is described in the National Research Council report, "Prudent Practices for Handling Hazardous Chemicals in Laboratories" (1), and other books on laboratory safety provide similar advice (2,3). Briefly, the procedure calls for carrying out most laboratory operations in a well-ventilated area (e.g., a fume hood or a glove box) and avoiding skin contact with chemicals. A more detailed description follows. 

For the membrane array of cytokine expression, the general procedures (Amersham Pharmacia Biotech R D Systems SuperArray Inc., Bethesda, MD Clontech Laboratories, Inc., Palo Alto, CA) include RNA extraction, reverse transcription into biotin- or radioisotope-labeled cDNA, hybridization with about 20 to several hundred different cDNA prespotted membranes, and signal detection using fluorescence or radioactive methods (L3). As an example, Fig. 4 and Table 4 show different chemokine genes upregulated in allergic asthmatic patients compared with normal controls, based on membrane array technology (SuperArray). 

The most commonly used procedure to fabricate a packed capillary column for CEC is depicted in Figs. 4.27 A and B. Although several laboratories may have slight variations, the general procedure is as follows. A piece of fused silica capillary of a... 

The general procedure which has been used for the preparation of ovotransferrin in relatively large quantity and with high purity in the laboratories at the University of California at Davis (27) is outlined in Diagram 1. The yield of crude ovotransferrin was equivalent to 15% of... 

Related Calculations. Use the general procedures given here for laboratory- and production-type high-vacuum systems. 

All substituted trifluoromethanesulfonanilide (TFMS) samples were prepared in the 3M Co. Biochemical Research Laboratory and supplied by J. K. Harrington and R. D. Trepka of that laboratory. General preparative procedures for the TFMS compounds and related perfluoro-alkanesulfonanilides have been outlined (1,2,3, 4, 5). Additional details of the sulfonylation procedures and subsequent modifications of the resulting products will be published later. 

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