Near-Infrared Analysis of Critical Parameters in Lyophilized Materials - Near-infrared spectroscopy is an effective and non-destructive way to analyze lyophilized materials. - BioPharm International

ADVERTISEMENT

Near-Infrared Analysis of Critical Parameters in Lyophilized Materials
Near-infrared spectroscopy is an effective and non-destructive way to analyze lyophilized materials.


BioPharm International
Volume 19, Issue 2


Figure 2. The Calibration Curve for Moisture.
This study details the analysis of thrombin, a lyophilized topical coagulant, by FT-NIR spectroscopy. Two critical parameters for thrombin are moisture (usually below 1.0%) and potency. Traditionally, moisture measurements are carried out by Karl Fischer titration, a USP-referenced technique (USP <921>). Potency is established using light- scattering measurements after the sample is titrated with plasma. If the sample potency is high, the thrombin will coagulate the plasma, creating particulates. Greater potency creates more particulates, resulting in increased light scattering from the sample. Both of these techniques are destructive and require a skilled operator. Both are also time-consuming and use consumables like solvents, plasma, or reagents.

EXPERIMENTAL


Figure 3. The Percent Residual for Moisture.
Two sets of ten thrombin samples were used to establish calibrations for moisture and potency. The samples were pulled from finished product lots and analyzed through the vial using a Nicolet Antaris FT-NIR analyzer with a LyoCheck solution package from Thermo Electron Corp. The autosampler RS attachment was used to collect all sample data without operator interaction. Thirty-two scans were taken of each sample and co-averaged at a resolution of 4.0 cm–1 . Each sample took approximately 20 sec to analyze. The wavelength range scanned was 4,000 cm–1 to 10,000 cm–1 . Once the samples were analyzed on the FT-NIR spectrometer, they were analyzed destructively using the primary technique — Karl Fischer titration for the ten moisture samples and light-scattering plasma titration for potency. These primary numbers were then combined with the spectral data in multivariate analysis methods using TQ Analyst, a chemometric analysis software package.

MOISTURE RESULTS


Figure 4. The Cross Validation Curve for Moisture.
Spectral data from the FT-NIR analyzer were combined with primary numbers from Karl Fischer titration for ten production samples. The moisture values ranged approximately from 0.5% to 0.8%. The data were combined using the analytic software to construct a chemometric model using the Stepwise Multiple Linear Regression (SMLR) algorithm. Data pretreatment of NIR spectra is common to help the various algorithms predict analytes accurately. In some cases, the primary or secondary derivative of the raw spectrum may prove more effective for measurement. Other pretreatments include pathlength algorithms like multiplicative scatter correction or standard normal variate, smoothing, or baseline corrections. In this case, the pretreatments were minimal as moisture is usually a strong absorber in the NIR range. The second derivative of the spectra was used for making the calibration curve with a 9,2 Norris smoothing filter. The regions chosen were constrained around 7,000 cm-1 , the first water overtone band. The water overtone region for the ten standards is shown in Figure 1.


blog comments powered by Disqus

ADVERTISEMENT

ADVERTISEMENT

AbbVie/Shire Deal Officially Off
October 20, 2014
Amgen Sues Sanofi and Regeneron over Patent for mAb Targeting PCSK9
October 20, 2014
EMA Works to Speed Up Ebola Treatment
October 20, 2014
Lilly to Close Manufacturing Facility in Puerto Rico
October 17, 2014
BioReliance Introduces New Predictive Assays
October 17, 2014
Author Guidelines
Source: BioPharm International,
Click here