HPLC operating conditions

Table 3 HPLC operating conditions for the determination of anilides... 

HPLC and LC/MS. HPLC methodology coupled with ultraviolet (UV), fluorescence (FL), photodiode-array (PDA) and/or a mass spectrometry (MS) detection has been developed. In general, neonicotinoids can be determined by HPLC/UV. Typical HPLC operating conditions are given in Table 2. 

B. HPLC operating conditions for confirmatory analysis on the Quattro II triple-quadrupole mass spectrometer... 

Sample Preparation and Selection of HPLC Operating Conditions... 

In certain cases, affinity columns can be used to fractionate within classes of bound materials for instance, protein A antibody columns have been used to separate the various subtypes of IgG. In this case, the packings are micro-porous, heavily cross-linked polymers and benefit from HPLC operating conditions. Eluting conditions are usually step gradients of buffers with different pHs. The last step of a protein G column is at a very acidic pH and the sample is eluted into a buffer solution that quickly raises the pH to prevent protein denaturation. 

Figure 9.103 Separation of FoTP, FoMP, and cFoMP by HPLC. Operating conditions 0.01 M KH2PO4 (pH 5.5) buffer with 10% methanol flow rate, 2 mL/min room temperature juBondapak C18 column packing fluorescence, excitation at 300 nm and emission above 320 nm. Approximately 10 jug of each component was injected. (From Rossomando et aL, 1981a.)...

Table 2.4 HPLC operating conditions and parameters snitable for the qnantitative analysis of amphetamines...

Table 7.2 HPLC operating conditions and parameters used for the quantitative analysis of mescaline [2]...

Barbiturates can be prepared for HPLC analysis by dissolution of the drug sample in methanol at a chosen concentration, followed by removal of any sofid particulate material by filtration, etc. A typical set of HPLC operating conditions used for the analysis of barbiturates is shown in Table 9.4. 

The basic principles behind the quantification of benzodiazepines are the same as those applicable to barbiturates. A typical set of HPLC operating conditions used for such analyses are shown in Table 9.5. Again, the compounds elute in order of increasing lipophilicity and, owing to the lack of any good chromophoric groups (cf. the barbiturates), a UV detection wavelength of 240 nm is also used for such materials. 

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