Specificity study procedure

On the other hand, single-residue methods developed by the applicants give basic information about appropriate cleanup steps and specific determination procedures. In addition, not many laboratories other than those from the applicants are able to test the real solvent extraction efficiency. The reason is that extraction studies need radio-labeled incurred residues instead of fortified samples. Hence enforcement methods provided by the manufacturers accelerate the development of methods which meet the needs of (official) food control laboratories. 

An alternative or additional step to flame annealing is electrochemical or chemical polishing. The fundamental aspects of electropolishing were reviewed recently [185], and a list of polishing procedures and parameters is available [185,186]. This method has been successfully applied to the preparation of gold, silver, and copper electrodes for STM studies [177,180,188]. It is important to note that different mesoscopic structures may arise according to the specific preparation procedures. For example, electropolishing a mechanically prepared Au(lOO) surface followed by... 

In Table 1, the typical validation parameters required for the different types of analytical procedures are listed. For all these analytical procedures CE might be an appropriate analytical technique. In fact numerous validated CE methods for pharmaceutical analysis have been described in literature during the last decade.In Table 2, an overview is listed of the ICH validation parameters included in several reported CE validation studies. Since chiral purity determination is an important application area of CE methods, this test is listed separately as a specific analytical procedure. In addition, the determination of drug counterions has been included as a separate application. This overview illustrates that in general the required validation parameters are addressed in reported CE validation studies. It should be noted, however, that the validation parameters included in Table 2 are not necessarily evaluated exactly according ICH requirements in the reported references. Many pharmaceutical companies apply a phase-related validation approach in which the depth of validation depends on the clinical phase of development of the product involved. 

At about the same time, studies were performed to determine whether psychopharmaceuticals or specific psychotherapeutic procedures produced better results in the treatment of mental disorders, especially schizophrenia and depression. 

R. D. Larsen, T. R. Verhoeven, and P. J. Reider, Mechanistic study of the Jacobsen asymmetric epoxidation of indene,/. Org. Chem. 1997, 62, 2222-2229. International Conference on Harmonisation Guidance on Q A Specifications Test Procedures and Acceptance Criteria for New Drug Substances and New Drug Products, Chemical Substances. Federal Register 2000, December 29, 65(251), Notices Food and Drug Administration [Docket No. 97D-0448],... 

In the few studies reporting on loading processes, specific analysis procedures have been developed in order to evaluate the course of the aminosilane deposition. Those include various in situ FTIR techniques as well as solvent analysis by various... 

Initial clinical work focused on a product that would be used to convert patients who were hospitalized for recent-onset AF as an alternative to a cardioversion procedure. Cardiome partnered with Fujisawa (now Astellas Pharmaceuticals) for the clinical development of a vernakalant (1), which produces robust AF conversion rates and none of the ventricular conduction abnormalities associated with less selective agents.35 By the close of 2009, vernakalant had been in 5 large trials and several smaller trials, including a total of over 1200 AF patients. Four Phase III studies—Atrial Arrhythmia Conversion Trials (ACT 1, 2, 3, and 4) —examined patients with recent onset AF (< 45 days) and the measured the rate of conversion to NSR in various periods after drug administration.36 38 The conversion rate was 45-63% in these studies, which tended to exclude patients with more compromised heart function or a history of heart failure. While there has been no specific study looking at QT prolongation, monitoring in both patients and in healthy volunteers showed only modest increases in the QT interval with no directly associated incidents of TDP across all trials. 

The limitation to low conversion is the major disadvantage of differential operation. This is not critical if the influence of the catalyst properties on deactivation is studied. If, on the other hand, one is interested in the mechanism and the kinetics of coke formation and in the deactivation of the main reactions, it is necessary to reach higher conversions. A solution to this problem is to combine the electrobalance with a recycle reactor. The recycle reactor is operated under complete mixing, so that the reactor is gradientless. Since in a completely mixed reactor the reactions occur at effluent conditions and not at feed conditions, a specific experimental procedure is necessary to obtain the deactivation effect of coke. 

This approach was pioneered by the group of Yates [43]. Using standard mixtures of proteins, they established the proteins in the mixtures with 30-fold difference in molar quantity can still be successfully identified. Initially, the method was applied to protein mixtures obtained by immunoaffinity precipitation or similar specific isolation procedures based on protein interaction (Ch. 17.4.1). In another study, E. coli periplasmic proteins were identified by the same approach [44]. The protein fraction was enriched using anion-exchange chromatography (AEC). Part of each fraction was separated by GE. The proteins were detected by silver staining. 

Other Chemical and Physical Methods. Polarography has been tried in special investigations, such as studies of the bound form of ascorbic acid. But because of limited specificity, the procedure has not seen wide application (82,83). Ascorbic acid is oxidized at the dropping mercury electrode, the basis of the polarographic determination. Dehydroascorbic acid is not measured, however, since it is not reducible at the dropping mercury electrode. Mason et al. (84) have developed a method for the determination of ascorbic acid based on electrochemical oxidation at the tubular carbon electrode that has been modified to measure water-... 

Specificity Study. Compounds used for the specificity study were monensin, lasalocid, narasin, salinomycin, lincomycin, chlortetracycline and roxarsone. The compounds were first dissolved in acetone or acetonetwater (8 2 v/v) at a concentration of 1 mg/mL. Further dilutions were prepared in PBS 7.6. Concentrations ranging from 0 to 10 xg/mL were tested. The assays were performed by using 50 xL of the varying concentrations of the compounds in place of the maduramicin in the standard curve procedure as described above. The concentration of the competing compounds required to exhibit 50% displacement of the antibody binding to the solid support was calculated. 

In recent years, attention has tended to be focused on coke deposition in zeolites (6, 7) in order to characterise the coke formed. In one specific study Groten et al (8) carried out a study of coke formation using zeolite USHY with n-hexane as reactant, but in this case, as in others (6, 7) it was necessary to deposit excessive amounts of coke (> 5%) to enable characterisation of the coke deposits to be achieved. However, if demineralisation of the catalyst is used to concentrate the coke as in the present work the inherently quantitative single pulse excitation (SPE) NMR procedure may be used to characterise coke deposits on FCC catalysts at realistic levels of ca 1% by weight. 

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