Quantitation range

The concentration of analyte in the unknown sample is extrapolated from the calibration curve. To obtain an accurate and precise quantitative value, the optical density (OD) for the sample solutions must fall on the linear portion of the calibration curve. If the sample OD is too high, the sample solution must be diluted until the OD falls within the quantitative range of the assay. The concentration of the analyte in the original sample is calculated by correcting for any dilution factor that was introduced in preparing the sample for application to the microplate. 

A classic pharmaceutical science textbook might have defined poor solubility as anything below a solubility of 1 g mL-1 (2 mol L-1 solution for a molecular weight of 500 Da) at pH 6.5 (or pH 7). This classic view is reflected in the Chemical Abstracts SciFinder 2001 solubility range definitions for solubility calculated using Advanced Chemistry Development (ACD) Software Solaris V4.67. These semi-quantitative ranges for molar solubility are very soluble, 1 mol L 1 < solubility soluble, 0.1 mol L 1 < solubility < 1 mol L 1 slightly soluble, 0.01 mol L 1 <... 

An online filter was also used to protect the analytical column. A guard column was used before the T to prevent breakthrough. A restrictor was used to balance the pressure before, during, and after the valve switches. After sample transfer, the valve was switched back. With this method, both water-insoluble retinoids and water-soluble retinoic acid were extracted simultaneously. Because of the minimal light exposure of these light-sensitive analytes during the procedure, an extraction recovery of 97 to 100% was achieved with a quantitation range of 100 fmol to 3 nmol. 

Recently, three papers have reported the determination of risperidone and its active metabolite 9-hydroxyrisperidone using LLE and SPE technologies. The analytical columns used to separate these compounds were C4 or C18 bonded phases of 3 pm or 5 pm particle sizes with UV/VIS detection. Mobile phases consisted of phosphate bufiers (pH 3-4) in acetonitrile. The sample volumes used ranged from 200 pi to 1 ml, with extraction recoveries averaging 90%. The limits of quantitation ranged from 0.5 to 10 ng/ml in human plasma (Nagasaki et al., 1999 Avenso et al., 2000 Titier et al., 2002). A study by Titier showed the simultaneous determination of clozapine, olanzapine, haloperidol, risperidone, and its active metabolites by RP-HPLC in human plasma. The assay involved LLE with a hexane/isoamyl alcohol mixture... 

For Nd-based catalyst systems the quantitative range of halide donors investigated falls between 0 < x/ Nd < 10. A maximum in catalyst activity is usually observed at molar nx/ Nd-rali°s between 2 and 4, e.g. [49,89,168, 178,187,232,272,318]. Various factors such as addition order of the catalyst components, catalyst preformation and catalyst aging have an influence on the location of the optimum molar nx/n -xdXio (Sect. 2.1.6). 

Calibration To optimize quantitation Quantitation range is defined and... 

The qualitative and quantitative range of responses of the species tested. 

Not Detected Detected, Unidentified Detected, Identified Linear Quantitation Range Out of Range... 

In contrast, with its intrinsically higher selectivity, tandem mass spectrometry offers a much more effective and practical approach for multicomponent quantitation. This translates into faster method development and, ultimately, rapid and reliable multicomponent quantitation. The routine application of multicomponent quantitation to 5 or 10 compounds in a cassette can be developed in 1 or 2 days, offering typical quantitation range of 5 to 5000 ng/mL. The variability of the assay procedure ranges from 10 to 20%, which is less than the typical intersubject pharmacokinetic variability of 25 to 30%. 

Studies of the detection of fumonisin B1 by using a fiber-optic inununosensor showed that the sensor could detect fumonisin B1 in a quantitative range of 10-1,000 ng mL with a limit of detection of 10 ng mL . ... 

Validation of bioanalytical methods requires experiments to assess accuracy, precision, limit of detection, limit of quantitation, range, linearity, selectivity, and sample stability (23). The sample preparation step has a great impact on all these parameters. The extraction efficiency must be experimentally determined by comparison of extracted samples to unextracted standards (24,25). The unextracted standards, because of interference, must be diluted in saline or the mobile phase rather than plasma. 

Most LBAs require some level of sample dilution prior to analysis due to either the assay MRD or high analyte concentrations in the study samples. It is imperative to demonstrate during method development that the analyte, when present in levels above the ULOQ, can be diluted to concentrations within the quantitative range. This may be accomplished by illustrating that the analytical recovery of an ultrahigh matrix spike ( 100 1000 times ULOQ), diluted serially in assay matrix, remains acceptable over a wide concentration range (when corrected for the dilution factor). Dilutional linearity experiments often reveal the presence of a prozone or Hook effect, which is discussed in the next section. 

This parameter may be defined as a condition in which dilution of test samples does not result in biased measurements of analyte concentration. Thus, when a test sample is serially diluted to result in a set of samples having analyte concentrations that fall within the quantitative range of the assay, there is no apparent trend toward increasing or decreasing estimates of analyte concentrations over the range of dilutions. 

Calcium carbide 03 2 + H2O C/2H2 H C/3(0H)2 Acid titration Not always quantitative, range >1% water depending upon the sample... 

The range of reliable response (also known as the calibration range or quantitation range) is the range of concentration that can be reliably and teproducibly quantified with specified accuracy and precision through the use of a concentration-response relationship. The latter is referred... 

The concentration of standards chosen to establish a calibration function must cover the expected quantitation range and should be set at approximately equally spaced intervals. If the concentra-... 

The first definition begs the question What does several mean In practice it is likely to be very difficult to assess SIL requirements unless there is a set of agreed definitions of the parameter values, almost inevitably in terms of quantitative ranges. These may or may not have been calibrated against the assessing organisation s risk criteria, but the method then becomes semi-quantitative (or is it semi-qualitative It is certainly somewhere between the extremities of the qualitative / quantitative scale.)... 

In 2002, Indyk and co-workers evaluated vitamin B12 in a range of foods such as milks, infant formulas, meat and liver using SPR technology with performance parameters including a quantitation range of 0.08-2.4 ng/mL with recoveries of 89-106% (Indyk et al. 2002). The analytical technique was biosensor based utilizing bimolecular interaction. 

---