High-throughput And Nondestructive Measurement Of Catalytic Activity Concentrations Of Two Aminotransferase By Near Infrared Spectroscopy

The aminotransferase in human serum is a kind of enzyme which participates in amino acid synthesis and decomposition.The catalytic activity concentrations of aminotransferases can reflect the human health.Alanine aminotransferase(ALT)and aspartate aminotransferase(AST)are important serum biomarkers which are used to diagnosis or predict many diseases in clinical practice and ALT are quality control of blood products.ALT and AST are measured by the routine test methods,which are low-throughput,time consuming,expensive and environmental pollution.Therefore,the routine test methods fail to meet the rapid developing society.In this article,the feasibility of the measurement of catalytic activity concentrations of serum transaminase is evaluated by near infrared spectroscopy(NIRS).The partial least squares(PLS)models which were constructed using near infrared transmittance spectra(NIRTS)were established for predicting catalytic activity concentrations of ALT and AST.The strategy is high-throughput,nondestructive,fast,pollution-free and inexpensive that it will be useful in programs of emergency and public health screening.OBJECTIVE:The article was to establish high-throughput and nondestructive measurement of catalytic activity concentrations of ALT and AST in human serum using NIRS with chemometric techniques.METHODS:1.Measurements of reference values and NIRTS of serum samplesThe catalytic activity concentrations of serum ALT and AST were measured using the BS-800 M chemistry analyzer.Then the transmission spectra of serum samples were measured by Antaris II FT-NIR analyzer,which furnished with an indium gallium arsenide(In GaAs)detector.All spectra were acquired under the same measurement conditions,i.e.the scan region of 10000 to 4000 cm-1,the resolution of 8 cm-1,the scan number of 64,the room temperature of 25 ± 5?C,and the humidity of 55 ± 5%.Each sample was loaded and measured after the background spectrum was got.2.Measurement of catalytic activity concentration of ALT by NIRSThe PLS model was constructed using the NIRTS of serum samples to predict the catalytic activity concentration of ALT.3.Measurement of catalytic activity concentration of AST by NIRSThe PLS model was constructed using the NIRTS of serum samples to predict the catalytic activity concentration of AST.RESULTS:1.Measurements of reference values and NIRTS of serum samplesThe reference values and 125 NIRTS of 125 serum samples were acquired.2.Measurement of catalytic activity concentration of ALT by NIRSThe optimal PLS model of ALT with the low RMSEC value 10.8 and RMSEP value 10.8 was established after the spectra were processed only by mean centering(MC)using 7500 – 7200 cm-1,7000 – 6700 cm-1 and 6600 – 6500 cm-1.The regression equation for ALT calibration set was y = 0.8509 x + 5.836.The value of RC was 0.9224 which revealed a good linear relationship between the reference and prediction values in the test range of 3.03 – 101.24 U/L.3.Measurement of catalytic activity concentration of AST by NIRSThe optimal PLS model of AST with the low RMSEC value 5.49 and RMSEP value 6.29 was established after the spectra were processed by first derivative(FD),Savitzky-Golay smoothing(SGS),MC and variance scaling(VS)using 7500 – 7200 cm-1,7000 – 6700 cm-1 and 6600 – 6500 cm-1.The regression equation for AST calibration set was y = 0.8467 x + 5.215.The value of RC was 0.9202 which revealed a good linear relationship between the reference and prediction values in the test range of 12.30 – 67.73 U/L.CONCLUTION:The catalytic activity concentrations of ALT and AST in serum can be determined simultaneously by using the NIRS which we established.The strategy can be used for ALT and AST evaluation in clinical practice.