Chemistry Reference
In-Depth Information
Biologic:
A virus, therapeutic serum, toxin, antitoxin, or related substance used for
human treatment or disease prevention.
Biological Matrix:
Samples of biological origin, typically blood, serum, plasma,
urine, feces, saliva, sputum, and tissues.
Biotechnology:
The use of living organisms or other biological systems in the man-
ufacture of drugs or other products or for environmental management, for
example, waste recycling.
Blank:
A sample that does not include the analytes of interest, used to assess the
specificity of a method. Examples include mobile phase, diluent, and pro-
cedural blanks.
Calibration:
Ensures that the instrument response correlates with the response of
the standard or reference material. Calibration should be carried out by
documented written and approved procedures, using traceable certified
standards.
Capacity Factor:
A chromatographic parameter (kʹ) that measures the degree of
retention. Calculated from the equation: kʹ = (t
R
− t
0
)/t
0
, where t
R
is the reten-
tion time and t
0
is the retention time of an unretained peak.
Certification:
A documented statement or written guarantee by qualified individu-
als that an instrument, computer, test, or system complies with specified
requirements.
cGMP:
Current Good Manufacturing Practice. See Title 21, Code of Federal
Regulations, Section 210, 211, and 212.
Change Control:
A monitoring system of managing and implementing changes that
may affect the status of a validated process. Change control is a way to
determine the need for corrective actions that might be necessary to correct
or redesign systems or, for example, upgrading software while maintaining
a validated state.
Coefficient of Determination:
The square of the correlation coefficient.
Coefficient of Variation (CV):
The sample standard deviation divided by the sam-
ple average, multiplied by 100. Sometimes called
relative precision
or
rela-
tive standard deviation
.
Confidence Interval/Limits:
Usually expressed as a percentage (e.g., 95%) refer-
ring to the range of values around an observed value that will include the
expected value.
Confidence Level:
Usually expressed as a percentage (e.g., 95%) referring to the
probability of precision measurements. A 95% confidence level means a
95-in-100 chance of being correct or a 5-in-100 chance of being wrong in
predicting that the precision falls into a specified range.
Conformance to Specifications:
The sample, when tested according to a docu-
mented analytical procedure, satisfies the listed acceptance criteria.
Corrective Action:
Action to eliminate the cause of a detected nonconformity to
prevent recurrence.
Correlation Coefficient, r:
Degree of correlation between two variables, ranges from
−1 to +1. A +1 value indicates a perfect correlation with both values increas-
ing; a value of −1 also indicates a perfect correlation, with one value increas-
ing while the other is decreasing. A zero r value indicates no correlation.
