Near-infrared analysis forms

The phase composition of glycine crystal forms during the drying step of a wet granulation process has been studied, and a model developed for the phase conversion reactions [88], X-ray powder diffraction was used for qualitative analysis, and near-infrared spectroscopy for quantitative analysis. It was shown that when glycine was wet granulated with microcrystalline cellulose, the more rapidly the granulation... 

Melucci D. Monti D. D Elia M. Luciano G. Rapid in-situ repeatable analysis of drugs in powder form using reflectance Near-Infrared Spectroscopy and multivariate calibration. Journal of Forensic Sciences, 2012, 57, 86-92. 

R. Gimet and A.T. Luong, Quantitative determination of polymorphic forms in a formulation matrix using the near infrared reflectance analysis technique, J. Pharm. Biomed. Anal., 5, 205-211 (1987). 

J.D. Kirsch and J.K. Drennen, Near-infrared spectroscopy applications in the analysis of tablets and solid pharmaceutical dosage forms, Appl Spectrosc. Rev., 30(3), 139-174 (1995). 

P. Corti, G. CerameUi, E. Dreassi and S. Mattii, Near infrared transmittance analysis for the assay of sohd pharmaceutical dosage forms. Analyst, 124, 755-758 (1999). 

Samples for analysis may be solids, liquids, or gases, or any forms in between and in combination, such as slurries, gels, and gas inclusions in solids. Samples can be clear or opaque, highly viscous or liquids with lots of suspended solids. While this variety is easy for Raman spectroscopy, it would be challenging for mid-IR and near-infrared (NIR) spectroscopy and numerous non-spectroscopic approaches. 

Gimet, R. Luong, A.T., Quantitative Determination of Polymorphic Forms in a Formulation Matrix Using the Near Infrared Reflectance Analysis Technique /. Pharm. Biomed. Anal. 1987, 5, 205-211. 

Other spectrophotometric techniques have been reported for the analysis of spironolactone. Near infrared diffuse reflectance first-derivative spectroscopy was used for determination of spironolactone in pharmaceutical dosage forms [30]. Readings were taken at 15 nm intervals, and then 81 absorbance readings were imput into a computer for principal component analysis. 

Vibrational Spectroscopy [Infrared (mid-IR, NIR), Raman]. In contrast to X-ray powder diffraction, which probes the orderly arrangement of molecules in the crystal lattice, vibration spectroscopy probes differences in the influence of the solid state on the molecular spectroscopy. As a result, there is often a severe overlap of the majority of the spectra for different forms of the pharmaceutical. Sometimes complete resolution of the vibrational modes of a particular functional group suffices to differentiate the solid-state form and allows direct quantification. In other instances, particularly with near-infrared (NIR) spectroscopy, the overlap of spectral features results in the need to rely on more sophisticated approaches for quantification. Of the spectroscopic methods which have been shown to be useful for quantitative analysis, vibrational (mid-IR absorption, Raman scattering, and NIR) spectroscopy is perhaps the most amenable to routine, on-line, off-line, and quality-control quantitation. 

Near infrared In situ analysis of solid-state conversions identification and quantification of polymorphs in dosage forms... 

Ciurczak, E.W. Torlini, R.P. Analysis of solid and liquid dosage forms using near-infrared reflectance spectroscopy. Spectrosc. 1987, 2 (3), 41 3. 

Kaushik D, Madan K, Dureja H. Near-infrared spectroscopy Applications in solid dosage form analysis. Tablets Capsules 2(X)6 4(7) 22-i. 

Recently, ICH guidance Q6A has simplified the development of specifications in several ways, not the least of which is the clarification that impurities if already controlled in the API do not have to be controlled in the dosage form unless they are also degradants. For the release assay, this paves the way for simpler, but no less sophisticated methods that require minimal sample preparation. Thus, the future may bring a return to spectroscopic techniques such as ultraviolet/visible (LJV/vis) spectroscopy. There also may be increased use of other high-speed and high-precision techniques such as flow injection analysis (FIA) and near infrared (NIR) analysis. 

AM Tudor, MC Davies, CD Melia, DC Lee, RC Mitchell, PJ Hendra, SJ Church. The applications of near-infrared Fourier transform Raman spectroscopy to the analysis of polymorphic forms of cimetidine. Spectrochim Acta 47A 1389-1393, 1991. 

NMR and infrared (IR) spectroscopy are also used to investigate the chemical stability of drug substances. Determination of the hydrolysis rate of esters such as atropine by NMR,647 a nondestructive near-IR analysis of aspirin tablets,648 and determination of the hydrolysis rate of diltiazem by polarimetry649 have been reported. Unusual methods, such as measurement of the dielectric properties of dosage forms like gelatin and methylcellulose microcapsules (Fig. 160), have been used to detect physical changes.650-651 These changes... 

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