Used for HbA1c determination using the Beta-Thalassemia program on the Bio-Rad Variant II.

Instrument: Bio-Rad Variant II

Specimen Type: Filter Paper

Volume per test: n/a


The Bio-Rad Variant II Beta-Thalassemia Program utilizes ion exchange high performance liquid chromatography (HPLC) separation of normal and abnormal hemoglobins, and accurate determination of hemoglobin A2, F and A1c in whole blood samples. There is no interference from the Schiff base (aldamine), lipemia or temperature fluctuations.

The samples are automatically mixed and diluted on the Variant II Sampling Station (VSS) and injected into the analytical cartridge. The Variant II Chromatographic Station (VCS) sends a programmed buffer gradient of increasing ionic strength and pH to the cartridge, and the hemoglobins are separated according to their ionic interaction with the cartridge material. The separated hemoglobins pass through a dual-wavelength detector where the changes in absorbance are measured at 415 nm. Any background variations are corrected by an additional filter at 690 nm. The Variant II Clinical Data Management (CDM) software performs a reduction of the raw data collected from each analysis. A two level calibration is used for adjustment of the calculated HbA2, HbF and HbA1c values. The results in percent and a chromatogram are generated by the CDM for each sample. The peaks for HbA2, HbF and HbA1c are shaded on the chromatogram. These areas are calculated using an Exponentially Modified Gaussian (EMG) algorithm. The Bio-Rad Variant II Beta-Thalassemia Program also allows for accurate determination of HbA1c in the presence of hemoglobins A2, F, S,D, E and C.

Testing Range: 3.1-19.1%