Quality control reference standards

These principles are supported by a related set of studies that showed reliable inter-laboratory IHC staining for Her2/neu, ER, and so on could be achieved based on optimal AR-IHC protocols and stringent quality control using standard reference materials, even though ischemia time itself was uncontrolled and unknown.38 0... 

SACHEM Inc. of Cleburne, Texas, manufactures various concentrations of tetramethylammo-nium hydroxide (TMAH) solutions to meet customer specifications. To ensure consistent performance, electronic industry requires very narrow concentration specifications for the solutions. In SACHEM s quality control laboratory, standardized acids such as HC1 or H2S04 are used as titrants for the TMAH solutions to check their concentrations. The performance of the assay titration is controlled by daily analysis of internal reference standards (IRSs). If the IRS results are within controlled limits, then the assay results of a product can be reported. If not, the results cannot be reported until the root cause is uncovered and eliminated. Safety glasses and gloves are worn while performing this work in the laboratory. 

In HPLC, a sample is separated into its components based on the interaction and partitioning of the different components of the sample between the liquid mobile phase and the stationary phase. In reversed phase HPLC, water is the primary solvent and a variety of organic solvents and modifiers are employed to change the selectivity of the separation. For ionizable components pH can play an important role in the separation. In addition, column temperature can effect the separation of some compounds. Quantitation of the interested components is achieved via comparison with an internal or external reference standard. Other standardization methods (normalization or 100% standardization) are of less importance in pharmaceutical quality control. External standards are analyzed on separate chromatograms from that of the sample while internal standards are added to the sample and thus appear on the same chromatogram. 

A quality control (QC) standard mixture, a normal control and an abnormal control are run with each batch. The normal control is made by aliquoting 100-pl portions of a normal range pooled plasma into screw-cap vials. The abnormal control is made by spiking 50 ml of normal pooled plasma with defined concentrations of unlabeled acylcarnitine standards spanning the mass range covered by the analysis (see Reagents and Chemicals). The concentration for each standard should be chosen based on the upper limit of the reference range for the respective acylcarnitine species. The... 

Quality assurance refers to activities that demonstrate that a certain quality standard is being met. This includes the management process that implements and documents effective QC. Quality control refers to procedures that lead to statistical control of the different steps in the measurement process. So QC includes specific activities such as analyzing replicates, ensuring adequate extraction efficiency, and contamination control. 

IS015189 Medical Laboratories—-Particular Requirements for Quality and Competence is a universal standard for quahty management in medical laboratories that specifies requirements in general terms applicable to all medical laboratory fields, The standard is intended to form the basis for accreditation of medical laboratories. In addition to general laboratory conditions in relation to quality control, the standard focuses on medical competence, interpretation of test results, selection of tests, reference intervals, ethical aspects, and safety. An annex concerns quality management of laboratory computer systems. 

Quality Assurance and Quality Control. The terms "quality assurance"(QA) and "quality control"(QC) need to be defined. They are often used interchangeably, but to the professional they refer to two different activities. Quality control refers to those actions taken in the laboratory in an attempt to keep the measurement system in control. Examples would be running reference standards, calibrating Instruments, keeping quality control charts, etc. Quality assurance refers to the system or program whereby management assures itself (and its clients) that the quality control measures are being applied, and that the results reported do, in fact, refer to the sample that was submitted or collected by the laboratory. 

From a practical aspect, the expression quality control refers to a product that fulfills customer s expectations. These expectations or standards of performance are based on the intended use and selling price of the product. Control is the process of regulating or directing an activity to verify its conformance to a standard or specification and to take corrective action if required. Therefore, QC is the regulatory process for those activities that measure a product s performance, compare that performance with established standards or specifications, and pursue corrective action regardless of where those activities occur. 

Acid-Base Redox Compiexometric, Adsorption, and Luminescence Indicators. Quality Assurance Quality Control Primary Standards Reference Materials Production of Reference Materials. 

For the hygiene concept and quality control reference is made to those standards as well. 

Control charts may be utilized to monitor the variability of measurements from the quality control check standards and independent reference standards in order to optimally detect abnormal situations and ensure a stable measurement process. 

Noil, 5—Highly precise robotic or scmi-uulomatcd sample preparation systems are available commercially. These systems may be used to prepare calibration standards and samples for analyses provided that the results for the quality control reference material (Section 10) are met when prepared using the automated systems. 

These specifications and characteristics are defined with references to standard test methods which the different parties to a contract should conduct for quality control. The tables that follow show specifically the standards that are applicable in France, but a more general table in Appendix 2 shows the main test methods commonly referenced in specifications. 

A specification or standard for product characteristics is valid only if it is matched with references to well defined and recognized test methods, such that quality control tests conducted by the parties involved —client and supplier, for example— are comparable even if they are performed at different locations. 

The analysis was performed by XRF method with SR. SRXRF is an instrumental, multielemental, non-destructive analytical method using synchrotron radiation as primary excitation source. The fluorescence radiation was measured on the XRF beam-line of VEPP-3 (E=2 GeV, 1=100 mA), Institute of Nuclear Physics, Novosibirsk, Russia. For quality control were used international reference standards. 

The quality control of galvanic anodes is reduced mainly to the analytical control of the chemical composition of the alloy, to the quality and coating of the support, to an adequate joint between support and anode material, as well as to restricting the weight and size of the anode. The standards in Refs. 6, 7, 22, 27, 31 refer to magnesium and zinc anodes. Corresponding specifications for aluminum anodes do not exist. In addition, the lowest values of the rest potentials are also given [16]. The analytical data represent the minimum requirements, which are usually exceeded. 

The standard requires controlled conditions to include compliance with reference standards/codes, quality plans, and/or documented procedures. 

Laminated tapes In more general use now than pressure sensitive tapes are tapes consisting of polyvinyl chloride or polyethylene films in conjunction with butyl rubber. These tapes are applied with an adhesive butyl rubber primer. Thicknesses of up to 0-75 mm are in use and loose protective outer wraps of p.v.c. or polyethylene sheet are commonly applied. Tape quality control is exercised with reference to ASTM standard test methods and may include water vapour transmission rate and elongation. 

Enzyme Reference Serums. Several companies sell lyophilized or stabilized reference serums for the calibration of instruments and for quality control. The label values given for the enzymatic activity of these serums should never be taken at face value, as at times they may be quite erroneous (19,33). Also, these values should only be used for the assay with which they were standardized, as interconversion of activity from one method to another for the same enzyme may often lead to marked errors. For instance, it is not recommended that alkaline phosphatase expressed in Bodansky units be multiplied by a factor to convert it to the units of the Ring-Armstrong method, or any other method for that matter. 

Ievin BC, Cheng H and Reeder DJ (1999) A human mitochondrial DNA standard reference material for quality control in forensic identification, medical diagnosis, and mutation detection. Genomics 55 135-146. 

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