The aim of this study was to develop a new method for the determination of NO2 levels encountered in clinical settings as well as in environmental studies, using a bi−component atmospheric pressure ionization mass spectrometry(APIMS). Hydrogen (1%) diluted in pure argon was ionized by corona discharge in the first ionization component. Fifty ml of the analyte diluted in 250ml of composite air or carbon dioxide (CO2) was introduced into the second ionization component and analyzed. When composite air was used as the sample carrier gas, NO in the analyte was oxygenated and there was an increase in the NO2 content from that in the original analyte. However, when CO2 was used as the sample carrier gas, the level of NO2 in the analyte could be determined because CO2 did not change the NO2 content from that in the original analyte. A calibration curve with good linearity was obtained using the UG−410 APIMS system, with a regression equation of Y(%)=5.513*10-2 X(ppb) and a detection limit of 0.9ppb. Since APIMS detects NO2 directly within its system, the concentration of NO does not need to be measured. This system may be of great help in the accurate detection and determination of the concentration of low levels of NO2 during inhaled NO therapy
Carbon Dioxide ; ionization ; Spectrum Analysis, Mass ; Direct type of resin cement ; Adjudication

HbA1c is used for assessing glycaemic control in patients with diabetes. It is also used for treatment goals and as a target for therapeutic intervention. The Direct Control and Complications Trial in the USA showed that HbA1c can be used to predict the risk of complications. Hence, it is important for HbA1c assays to be standardised. The National Glycohemoglobin Standardization Program (NGSP) in the USA was formed in 1996 so that HbA1c results from different laboratories would be comparable to those reported in the DCCT study. There were also HbA1c standardisation programmes in Sweden and Japan. These three standardisation programmes are, in fact, direct comparison methods (DCMs), and yield different HbA1c results. In 1994, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) established a Working Group on Standardisation of HbA1c. This working group has developed a global HbA1c reference system with very much improved intra-assay and inter-assay coefficients of variation. Recommendations have been made to report HbA1c results as IFCC-HbA1c values in SI units (mmol HbA1c/mol Hb) and NGSP-HbA1c (%) as well as estimated average glucose (eAG), once a tight relationship has been shown to exist between eAG and HbA1c.
Glycosylated hemoglobin A ; Global ; assay ; Control brand of phenylpropanolamine ; Direct type of resin cement