Analysis of Small Organics

The direct interaction of small organic molecules with receptors immobilized on the sensor surface is difficult to detect. Two approaches may be used to detect or quantify the presence of small analytes in a process stream, displacement assays or competition assays. 

Displacement assays can be designed in at least two different ways, (a) Analyte may be immobilized on the sensor surface and the sensor loaded with anti-analyte 

2 Analysis of Laiger Analytes such as Production Proteins or Contaminants 

Larger analytes are readily detected by direct interaction with antibodies immobilized on the sensor surface (Fig. 9.5.6). Sensitivities for this type of assay are typically in the high nanomolar to high picomolar range. The sensitivity and specificity can be increased simultaneously with the use of secondary antibodies that are specific for an epitope other than the one bound by the surface immobilized antibodies. If very high sensitivity is required, several stages of amplification can be carried out, allowing for detection of femtomolar levels of protein. For example, mouse monoclonal capture antibodies can be immobilized on the sensor surface. 

The lower line (reference) is an average of three reference channels. Arrows indicate sample (100 ng mL botulinum toxoid A) and amplifier (anti-fcofu/mum antibodies) injection. 

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He Y. and Lee H.K., Large-volume sample stacking in acidic buffer for analysis of small organic and inorganic anions by capillary electrophoresis, Anal. Chem. 71, 995, 1999. 

FIGURE 3.1 Comparison of atmospheric pressure ionization mass spectrometry and other widely used analytical methods for analysis of small organic molecules. 

As polarity plays an important role in the analysis of small organic compounds such as pharmaceuticals (most organic compounds can be neutral), the introduction of MEKC resulted in a boom of applications in this area. In biomedical analysis with CE, MEKC is the technique of choice for the analysis of drugs in pharmaceutical preparations or in body fluids. Several groups of drugs have been analyzed with considerable success. A typical... 

CE-Sure small organic acids kit Kit for the analysis of small organic acids (CZE)... 

In this chapter we will discuss not only the methods and techniques used for analysis of small-organic-molecule libraries but also the approaches for generation of these libraries, with the understanding that synthesis, analysis, and screening of combinatorial libraries are the integrated parts of combinatorial technology. 

Fang L, Dreyer M, Chen Y, Plunkett M, Flacker M, Analysis of small organic combinatorial libraries by LC-MS, Proc. 45th ASMS. Conf, p. 401, 1997. 

This chapter provides an overview of modern HPLC method development and discusses approaches for initial method development (column, detector, and mobile phase selection), method optimization to improve resolution, and emerging method development trends. The focus is on reversed-phase methods for quantitative analysis of small organic molecules since RPLC accounts for 60-80% of these applications. Several case studies on pharmaceutical impurity testing are presented to illustrate the method development process. For a detailed treatment of this subject and examples of other sample types, the reader is referred to the classic book on general HPLC method development by L. Snyder et al.1 and book chapters2,3 on pharmaceutical method development by H. Rasmussen et al. Other resources include computer-based training4 and training courses.5... 

Comparisons of Population Analysis of Small Organic Compounds... 

R352 R. R. Gil, Constitutional, Configurational, and Conformational Analysis of Small Organic Molecules on the Basis of NMR Residual Dipolar Couplings , Angew. Chem. Int. Ed., 2011, 50, 7222. 

A short review on the application of RDCs in configurational and conformational analysis of small organic molecules has been written by Gil. ... 

El and Cl are suitable for the analysis of small organic species with high volatility and thermal stability. However, many molecules studied by organic chemists, biochemists, or environmental scientists, do not possess these features. Furthermore, El and Cl need to be operated under high vacuum. On the other hand, atmospheric pressure ionization techniques can be used in the analysis of polar and non-polar organic compounds that are thermally labile with low volatility. 

Lin, J.-Y, Chen, T.-Y., Chen, J.-Y., Chen, Y.-C. (2010) Multilayer Gold Nanoparticle-assisted Thermal Desorption Ambient Mass Spectrometry for the Analysis of Small Organics. Analyst 135 2668-2675. 

THIN-LAYER CHROMATOGRAPHY-DIRECT ANALYSIS IN REAL TIME IN ANALYSIS OF SMALL ORGANIC... 

THIN-LAYER CHROMATOCRAPHY-NO EXTERNAL ION SOURCE IN ANALYSIS OF SMALL ORGANIC MOLECULES... 

Chen, Y.C. and Wu, J.Y. 2001. Analysis of small organics on planar silica surfaces using surface-assisted laser desorption/ionization mass spectrometry. Rapid Commun. 

The conformational analysis of small organic molecules, based on molecular mechanics, has reached a certain state of maturity, and in most cases provides useful information on the various stable conformations of moderate-size molecules. The calculation generally involves the following steps. " ... 

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