(M1530-08-44) At Line Near Infrared Quantification of Alpha – Tocopherol in Process Production of Vitamin E Soft Gelatin Capsule

Purpose: Process Analytical Technologies (PAT) promotes the implementation of analytics equipment of rapid responses, which can be placed at-line, in-line or on-line for monitoring and data analysis via a scientific understanding of manufacturing processes approach in order to ensure the quality of the end product. At-line Infrared Spectroscopy (NIRS) combined with chemometrics is a PAT tool which allows to obtain chemical and physical information from organic molecules, provide a rapid response, reducing time of analysis obtaining accurate and precise results. Recently in 2021 FDA has approved the guidance document to development and Submission of NIRS Analytical Procedures, therefore, NIRS has become an attractive tool in the pharmaceutical industry. The aim of this work was to implement at- line NIRS transmittance spectroscopy and chemometrics as a PAT tool for quantification vitamin E (Alpha–tocopherol) in an oily transparent solution matrix in bulk at the end of mixing process and in liquid matrix of a Soft Gelatin Capsule (SGC). This study is important because once the mixing and encapsulation process of vitamin E is finished, if data is Knowing in real time avoids quarantining-time while waiting for the off-line lab results. Therefore, the reduction of manufacturing times improves the efficiency of personnel and instruments.

Methods: The pharmaceutical formulation studied is a high dose formulation (93g/ 100g) composed of one active pharmaceutical ingredient vitamin E (Alpha – tocopherol) and one excipient (diluent). The bulk medicine is a oily transparent solution matrix. After mixing-process, the medicine is soft gel-encapsulated.
Calibration and validation set. The calibration set samples were prepared in lab-scale equipment and taken from production samples. These samples in lab-scale consist of twelve concentration levels. Samples were into the range: 0, 10, 20, 30, 40, 50, 60, 70, 80 ,90, 95, 100 % w/w of vitamin E and to external set validation were prepared four concentration levels 65, 75, 85, 93 % w/w of vitamin E. In addition, samples of twelve commercial batches of vitamin E were obtained. The production samples were taken at the end of mixing time (45 min) and after soft gel-encapsulation. Six of these ten batches were included within the calibration set and six batches were included in an external validation set, used to evaluate the prediction capacity of the proposed models. Spectra acquisition. At-line NIR spectra were recorded in transmission mode using a NIR spectrophotometer (Brand FOSS, model 5000), 32 scans and 8 cm^-1 resolution, with a spectral range of 1100 - 2500 nm. Liquid samples were measured poured into a glass vial (1 mL) that was directly placed on the sampler tray without any sample preparation. The analysis time was 1-2 min. Data acquisition was performed in VISION3.6V. Samples were analyzed in triplicate and 4 spectra were taken from each replicate, total twelve scans were measured for 28 samples (n=336 spectra). For the construction of the chemometric model, principal component analysis, partial least squares regression (PLSR) and various spectral pretreatments were used. The Unscrambler X10.4 was the Chemometric Software used. In this study a reverse phase HPLC method was used as reference method to quantify the concentration of the samples used in the NIR calibration model. Equipment: Merck Lachrom; Colum: C18 (125 x 4.0) mm 5 μm; Mobile phase: Methanol; UV-detector: 287 nm.

Results: Figure 1a shows Original Spectra of vitamin E raw material and spectra excipient. With the objective of subtracting the chemical information, minimizing variations due to light scattering and improve the resolution of overlapping bands common pre-processing tools were used: standard normal variate, first and second derivative. Figure 1b shows Preteated NIR-Spectra of samples of the calibration samples and commercial batches of vitamin E at different concentrations, with first derivative. Original and pretreated spectra were used and seven PLS models were obtained. The predictive capacity of the PLS model was evaluated using statistical parameters. These models get the following results: Squared Error of Calibration SEC: from 0.04 to 0.12%; Squared Error of prediction SEP: from 0.07 to 0.91%; R² of Calibration: from 0.995 to 1.000 and R² of Validation: from 0.990 to 0.999; percentage of recovery of the samples obtained with the PLS model Vs HPLC results: from 97.31 ± 3.4 to 103.7 ± 0.9. The figure 2 show the quantification NIR-PLS model of calibration set sample Vitamin E.

Conclusion: The proposed method of quantification AT-LINE NIR-PLS model of alpha-tocopherol gives accurate and precise results. The implementation of At-line NIRS analysis to the quantification of Alpha–tocopherol provides real-time data to soft gel production process control. The analysis performed directly after the manufacturing step (not off-line in the lab), it enables the manufacturer to react immediately to process variations and reduce waste by potentially stopping the process and recapturing the batch.

References: 1. FDA. Guidance for Industry PAT: A Framework for Innovative Pharmaceutical Development, Manufacuring, and Quality Assurance. FDA . 2004;(September)
2. Donald A, Burns E. Handbook of Near-Infrared Analysis, Third Edition (Practical Spectroscopy). 2002.
3. Roggo Y, Chalus P, Maurer L, Lema-Martinez C, Edmond A, Jent N. A review of near infrared spectroscopy and chemometrics in pharmaceutical technologies. J Pharm Biomed Anal. 2007;44(3 SPEC. ISS.):683–700.
4. FDA. Development and Submission of Near Infrared Analytical Procedures Guidance for Industry. 2021;(Agosto).

Acknowledgements: We declare that there is no conflict of interest


Figure 1 a) Original NIR spectra of Alfa-tocopherol and excipient spectra. Figure 1 b) Pretreated NIR spectra of Alfa-tocopherol medicine at different concentrations pretreated whith first derivate- Savistky Goley 8 point.


Fig. 2. Quantification NIR-PLS model of calibration set sample of Vitamin E.