Rapid and nondestructive analysis of pharmaceutical products using near-infrared diffuse reflectance spectroscopy

Fingerprints of volatile flavor compounds from southern stinky tofu brine with headspace solid‐phase microextraction/gas chromatography–mass spectrometry and chemometric methods

“…Fingerprints were analyzed with different chemometric methods, such as the time shift alignment method, Shannon entropy (Gong, Liang, Xie, & Chau, ), correlation coefficient (Keyfi & Varasteh, ), and principal component analysis (Li, Du, Cai, & Shao, ; Poole & Poole, ; Spínola, Perestrelo, Câmara, & Castilho, ). Time shifts can be accurately aligned by correlation optimized warping (COW) method (Coutinho et al., ; van Nederkassel, Daszykowski, Eilers, & Heyden, ; Tomasi, Berg, & Andersson, ).…”

Discriminant analysis of Chinese patent medicines based on near-infrared spectroscopy and principal component discriminant transformation

“…Therefore, derivative calculation was adopted for removing the background. Because CWT achieves derivative calculation and smoothing simultaneously, it has been used for the purpose in our previous works [21][22][23][24][25]. In the calculation of this study, Haar wavelet and scale parameter 20 was employed.…”

“…In our previous works, NIR spectroscopy combined with different chemometric methods was studied for classification and discrimination of industrial products. In pharmaceutical products, classification of azithromycin tablets of four manufacturers was studied by principal component analysis (PCA) and the effect of morphology was examined by preparing the samples in four forms [21]. The results showed that both the samples from different manufacturers and the samples in different forms can be classified with the aid of chemometric multivariate analysis.…”

“…Thus a discriminant model was established to distinguish a class and the others. Besides, PCA was employed to reduce the dimension of the NIR spectra and continuous wavelet transform (CWT) was used for removing background [21][22][23][24][25].…”

Development and validation of a stability-indicating RP-HPLC method for the detection and quantification of azithromycin in bulk, and self-emulsifying drug delivery system (SEDDs) formulation

“…Accordingly, different analytical techniques were explored to detect and quantify AZM in pharmaceutical and biological samples as well as foodstuffs and environment. These include spectrophotometric ion pair complexation techniques, spectrofluorimetric analysis, and near-infrared diffuse reflectance spectroscopy (Rachidi et al, 2006), (Sayed et al, 2013;Li et al, 2012;Khashaba 2002). Other methods such as LC-MS/MS (Shen et al, 2010), thin layer chromatography-densitometry (A.…”