A rapid field test for the measurement of bovine serum immunoglobulin G using attenuated total reflectance infrared spectroscopy

Table 2 Comparison of calibration models and prediction results of the immunoglobulin G (IgG) concentration of 200 bovine serum samples, obtained using different pre-processing approaches for infrared spectra

			Calibration (n = 133)		Prediction (n = 67)
Pre-processing	PLS factors	RMMCCV (mg/dL)	r	RMSEC (mg/dL)	r	RMSEP (mg/dL)	RPD	RER
Smoothing (9 points)	14	335	0.97	364	0.92	340	2.6	8.8
Smoothing + normalization (SNV)	14	332	0.97	359	0.93	326	2.7	9.1
Smoothing + vector normalization	14	336	.097	367	0.93	331	2.7	9
1^st derivatives (9 points)	6	341	0.95	370	0.91	373	2.4	8
1^st derivatives + normalization (SNV)	6	338	0.95	355	0.91	362	2.4	8.2
1^st derivatives + vector normalization	6	340	0.96	357	0.91	362	2.4	8.2
2^nd derivatives (9 points)	5	363	0.97	382	0.88	424	2.1	7
2^nd derivatives + normalization (SNV)	5	358	0.97	376	0.87	429	2	7
2^nd derivatives + Vector normalization	6	356	0.97	376	0.89	409	2.1	7.3

PLS, Partial least squares, RMMCCV Root mean squared error of the Monte Carlo cross validation value, r Pearson correlation coefficient, RMSEC Root mean squared error of calibration;, RMSEP Root mean squared error of prediction, RPD (ratio of predictive deviation), SD divided by RMSEP, RER (range error ratio), Range divided by RMSEP; SNV Standard normal variate

ISSN: 1746-6148