1
|
Antonio M, Raffaghelli M, Maggio RM. Assessing Polymorphic Purity of Rifampicin in Double and Triple-Drug Fixed-Dose Combination Products. J Pharm Sci 2024; 113:930-936. [PMID: 37783271 DOI: 10.1016/j.xphs.2023.09.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/06/2023] [Accepted: 09/26/2023] [Indexed: 10/04/2023]
Abstract
First-line tuberculostatic agents, Rifampicin (RIF), Isoniazid (ISH), Ethambutol (ETB), and Pyrazinamide (PZA) are generally administered as a fixed-dose combination (FDC) for improving patient adherence. The major quality challenge of these FDC products is their variable bioavailability, where RIF and its solid state are key factors. In this work, the analysis of the impact of the polymorphism in the performance of RIF in RIF-ISH and PZA-RIF-ISH combined products was carried out by an overall approach that included the development and validation of two methodologies combining near-infrared (NIR) spectroscopy and partial least squares (PLS) to the further evaluation of commercial products. For NIR-PLS methods, training and validation sets were prepared with mixtures of Form I/Form II of RIF, and the appropriate amount of ISH (for double associations) or ISH-PZA (for triple associations). The corresponding matrix of the excipients was added to the mixture of APIs to simulate the environment of each FDC product. Four PLS factors, reduced spectral range, and the combination of standard normal variate and Savitzky-Golay 1st derivative (SNV-D') were selected as optimum data pre-treatment for both methods, yielding satisfactory recoveries during the analysis of validation sets (98.5±2.0%, and 98.7±1.8% for double- and triple-FDC products, respectively). The NIR-PLS model for RIF-ISH successfully estimated the polymorphic purity of Form II in double-FDC capsules (1.02 ± 0.02w/w). On the other hand, the NIR-PLS model for RIF-ISH-PZA detected a low purity of Form II in triple FDC tablets (0.800 ± 0.021w/w), these results were confirmed by X-ray powder diffraction. Nevertheless, the triple-FDC tablets showed good performance in the dissolution test (Q=99-102%), implying a Form II purity about of 80% is not low enough to affect the safety and efficacy of the product.
Collapse
Affiliation(s)
- Marina Antonio
- Área de Análisis de Medicamentos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química Rosario (IQUIR, CONICET-UNR), Suipacha 531, Rosario S2002LRK, Argentina
| | - Mariano Raffaghelli
- Laboratorio Industrial Farmacéutico S.E. French 4950, S3006ETP, Santa Fe, Argentina
| | - Rubén M Maggio
- Área de Análisis de Medicamentos, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario and Instituto de Química Rosario (IQUIR, CONICET-UNR), Suipacha 531, Rosario S2002LRK, Argentina..
| |
Collapse
|
2
|
Martínez-Acevedo L, Job Galindo-Pérez M, Vidal-Romero G, Del Real A, de la Luz Zambrano-Zaragoza M, Quintanar-Guerrero D. Effect of magnesium stearate solid lipid nanoparticles as a lubricant on the properties of tablets by direct compression. Eur J Pharm Biopharm 2023; 193:262-273. [PMID: 37944711 DOI: 10.1016/j.ejpb.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 10/15/2023] [Accepted: 11/05/2023] [Indexed: 11/12/2023]
Abstract
This study discusses the lubricant properties of magnesium stearate solid lipid nanoparticles (MgSt-SLN) and their effect on the tabletability, mechanical properties, disintegration, and acetaminophen-model dissolution time of microcrystalline cellulose (MCC) tablets prepared by direct compression. The behavior of MgSt-SLN was compared to reference material (RM) to identify advantages and drawbacks. The nanoprecipitation/ion exchange method was employed to prepare the MgSt-SLN. Particle size, zeta potential, specific surface area, morphology, and true density were measured to characterize the nanosystem. The MgSt-SLN particle sizes obtained were 240 ± 5 nm with a specific surface area of 12.2 m2/g. The MCC tablets with MgSt-SLN presented a reduction greater than 20 % in their ejection force, good tabletability, higher tensile strength, lower disintegration delay, and marked differences in acetaminophen dissolution when compared to the RM. The reduced particle size of the magnesium stearate seems to offer a promising technological advantage as an efficient lubricant process that does not affect the properties of tablets.
Collapse
Affiliation(s)
- Lizbeth Martínez-Acevedo
- Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Estado de México C.P. 54740, Mexico; Laboratorio de Desarrollo Galénico, Departamento de Sistemas Biológicos, Universidad Autónoma Metropolitana-Xochimilco, Cuidad de México C.P. 04960, Mexico
| | - Moises Job Galindo-Pérez
- Departamento de Tecnología Farmacéutica, Facultad de Estudios Superiores Zaragoza, Campus II, Universidad Nacional Autónoma de México, Ciudad de México C.P. 09230, Mexico; Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana-Cuajimalpa, Ciudad de México C.P. 05348, Mexico
| | - Gustavo Vidal-Romero
- Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Estado de México C.P. 54740, Mexico; Departamento de Tecnología Farmacéutica, Facultad de Estudios Superiores Zaragoza, Campus II, Universidad Nacional Autónoma de México, Ciudad de México C.P. 09230, Mexico
| | - Alicia Del Real
- Departamento de Ingeniería Molecular de Materiales, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Campus Juriquilla, Santiago de Querétaro, Querétaro C.P. 76230, México
| | - María de la Luz Zambrano-Zaragoza
- Laboratorio de Procesos de Transformación y Tecnologías Emergentes de Alimentos, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Estado de México C.P. 54714, México
| | - David Quintanar-Guerrero
- Laboratorio de Investigación y Posgrado en Tecnología Farmacéutica, Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Estado de México C.P. 54740, Mexico.
| |
Collapse
|
3
|
Vijayakumar J, Goudarzi NM, Eeckhaut G, Schrijnemakers K, Cnudde V, Boone MN. Characterization of Pharmaceutical Tablets by X-ray Tomography. Pharmaceuticals (Basel) 2023; 16:ph16050733. [PMID: 37242516 DOI: 10.3390/ph16050733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/07/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
Solid dosage forms such as tablets are extensively used in drug administration for their simplicity and large-scale manufacturing capabilities. High-resolution X-ray tomography is one of the most valuable non-destructive techniques to investigate the internal structure of the tablets for drug product development as well as for a cost effective production process. In this work, we review the recent developments in high-resolution X-ray microtomography and its application towards different tablet characterizations. The increased availability of powerful laboratory instrumentation, as well as the advent of high brilliance and coherent 3rd generation synchrotron light sources, combined with advanced data processing techniques, are driving the application of X-ray microtomography forward as an indispensable tool in the pharmaceutical industry.
Collapse
Affiliation(s)
- Jaianth Vijayakumar
- Centre for X-ray Tomography (UGCT), Ghent University, Proeftuinstraat 86/N3, 9000 Gent, Belgium
- Department of Physics and Astronomy, Radiation Physics, Ghent University, Proeftuinstraat 86/N12, 9000 Gent, Belgium
| | - Niloofar Moazami Goudarzi
- Centre for X-ray Tomography (UGCT), Ghent University, Proeftuinstraat 86/N3, 9000 Gent, Belgium
- Department of Physics and Astronomy, Radiation Physics, Ghent University, Proeftuinstraat 86/N12, 9000 Gent, Belgium
| | - Guy Eeckhaut
- Janssen Pharmaceutica, Turnhoutseweg 30, 2340 Beerse, Belgium
| | | | - Veerle Cnudde
- Centre for X-ray Tomography (UGCT), Ghent University, Proeftuinstraat 86/N3, 9000 Gent, Belgium
- Pore-Scale Processes in Geomaterials Research (PProGRess), Department of Geology, Ghent University, Krijgslaan 281/S8, 9000 Gent, Belgium
- Environmental Hydrogeology, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Princetonlaan 8A, 3584 CD Utrecht, The Netherlands
| | - Matthieu N Boone
- Centre for X-ray Tomography (UGCT), Ghent University, Proeftuinstraat 86/N3, 9000 Gent, Belgium
- Department of Physics and Astronomy, Radiation Physics, Ghent University, Proeftuinstraat 86/N12, 9000 Gent, Belgium
| |
Collapse
|
4
|
Amano Y, Misawa T, Miyazaki T, Ando D, Koide T, Izutsu KI, Kanazawa H, Hanaoka K, Yamamoto E. Real-time in situ X-ray micro-computed tomography study of the effect of impurities on the crystallization of amorphous nifedipine. J Pharm Biomed Anal 2023; 226:115248. [PMID: 36645986 DOI: 10.1016/j.jpba.2023.115248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/08/2023] [Accepted: 01/11/2023] [Indexed: 01/13/2023]
Abstract
Controlling the physical stability of noncrystalline active pharmaceutical ingredients remains a major challenge in the development of amorphous formulations such as amorphous solid-dispersion (ASD) formulations. To establish new evaluation and formulation strategies, the spatial distribution of the crystal phase in bulk amorphous nifedipine (NFD) was investigated as a model. The crystallization of amorphous NFD and the effect of a deliberately added impurity were investigated using powder X-ray diffraction (PXRD), differential scanning calorimetry and real-time in situ X-ray micro-computed tomography (X-ray CT). The stability data of amorphous samples, i.e., NFD and a mixture of NFD with an oxidative degradation product of NFD, impurity A (Imp A), at a weight ratio of 90:10, presented as percent amorphous remaining, suggests that Imp A accelerates the bulk crystal growth of NFD. Real-time in situ X-ray CT results showed surface-enhanced crystal growth and cavity formation in solid NFD samples. Moreover, the crystals were heterogeneous in density. These results suggest that Imp A affects the physical stability of the amorphous NFD. X-ray CT equipped with a heating unit can aid in-situ evaluation and assessment of physicochemical properties and physical stability of amorphous samples and formulations.
Collapse
Affiliation(s)
- Yuta Amano
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan; National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Takashi Misawa
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Tamaki Miyazaki
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Daisuke Ando
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Tatsuo Koide
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Ken-Ichi Izutsu
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Hideko Kanazawa
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan
| | - Kenjiro Hanaoka
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan
| | - Eiichi Yamamoto
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan.
| |
Collapse
|
5
|
Sodeifian G, Usefi MMB. Solubility, Extraction, and Nanoparticles Production in Supercritical Carbon Dioxide: A Mini‐Review. CHEMBIOENG REVIEWS 2022. [DOI: 10.1002/cben.202200020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Gholamhossein Sodeifian
- University of Kashan Faculty of Engineering, Department of Chemical Engineering 87317-53153 Kashan Iran
- University of Kashan Laboratory of Supercritical Fluids and Nanotechnology 87317-53153 Kashan Iran
| | - Mohammad Mahdi Behvand Usefi
- University of Kashan Faculty of Engineering, Department of Chemical Engineering 87317-53153 Kashan Iran
- University of Kashan Laboratory of Supercritical Fluids and Nanotechnology 87317-53153 Kashan Iran
| |
Collapse
|
6
|
Blaney G, Sassaroli A, Fantini S. Method for Measuring Absolute Optical Properties of Turbid Samples in a Standard Cuvette. APPLIED SCIENCES (BASEL, SWITZERLAND) 2022; 12:10903. [PMID: 37811485 PMCID: PMC10557469 DOI: 10.3390/app122110903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Many applications seek to measure a sample's absorption coefficient spectrum to retrieve the chemical makeup. Many real-world samples are optically turbid, causing scattering confounds which many commercial spectrometers cannot address. Using diffusion theory and considering absorption and reduced scattering coefficients on the order of 0.01 mm-1 and 1 mm-1, respectively, we develop a method which utilizes frequency-domain to measure absolute optical properties of turbid samples in a standard cuvette (45 mm × 10 mm × 10 mm). Inspired by the self-calibrating method, which removes instrumental confounds, the method uses measurements of the diffuse complex transmittance at two sets of two different source-detector distances. We find: this works best for highly scattering samples (reduced scattering coefficient above 1 mm-1); higher relative error in the absorption coefficient compared to the reduced scattering coefficient; accuracy is tied to knowledge of the sample's index of refraction. Noise simulations with 0.1 % amplitude and 0.1° = 1.7 mrad phase uncertainty find errors in absorption and reduced scattering coefficients of 4 % and 1 %, respectively. We expect that higher error in the absorption coefficient can be alleviated with highly scattering samples and that boundary condition confounds may be suppressed by designing a cuvette with high index of refraction. Further work will investigate implementation and reproducibility.
Collapse
Affiliation(s)
- Giles Blaney
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Angelo Sassaroli
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| | - Sergio Fantini
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA
| |
Collapse
|
7
|
Keskinoğlu C, Aydın A. The Design of Low-Cost Stand-Alone Microcontroller-Based Wireless Ultrasonic System for Process Monitoring and Analysis. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2022; 41:2577-2589. [PMID: 35103346 DOI: 10.1002/jum.15948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/11/2021] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
OBJECTIVES Ultrasound technology is currently used in many areas, such as imaging, analysis, and process monitoring. The noninvasive implementation, nondestructive effect on the material to be applied, and low cost of the needed components give an advantage to the ultrasonic systems when compared to other methods for analysis and process monitoring studies. However, the current ultrasonic analysis setups used in the studies require additional devices such as a signal generator and oscilloscope. These devices used in the setup increase the cost, size, usage difficulty of the system and, most importantly, decrease the portability and stability. In order to prevent these disadvantages, an ultrasonic system that can work in real-time and its software are developed to be used in analysis and process monitoring without any additional devices. METHODS This system was designed by using a microcontroller. The developed system is portable, has a small size, and a Bluetooth Low Energy connection. It has a battery for using standalone. RESULTS Therefore, it can be easily used in different small and closed measurement environments such as incubators and controlled remotely. In addition, a mixture was analyzed with both the designed system and a commercial module. When the results are compared, two systems are found highly correlated r 2 = 1 . CONCLUSION: In this study, an embedded ultrasonic measurement system and its software are developed to be used in analysis studies, density measurements, and real-time process monitoring as a stand-alone device.
Collapse
Affiliation(s)
- Cemil Keskinoğlu
- Department of Biomedical Engineering, Cukurova University, Adana, Turkey
| | - Ahmet Aydın
- Department of Biomedical Engineering, Cukurova University, Adana, Turkey
| |
Collapse
|
8
|
Sadeghi A, Su CH, Khan A, Lutfor Rahman M, Sani Sarjadi M, Sarkar SM. Machine learning simulation of pharmaceutical solubility in supercritical carbon dioxide: Prediction and experimental validation for busulfan drug. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2021.103502] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
|
9
|
Stranzinger S, Wolfgang M, Klotz E, Scheibelhofer O, Ghiotti P, Khinast JG, Hsiao WK, Paudel A. Near-Infrared Hyperspectral Imaging as a Monitoring Tool for On-Demand Manufacturing of Inkjet-Printed Formulations. AAPS PharmSciTech 2021; 22:211. [PMID: 34374899 PMCID: PMC8354920 DOI: 10.1208/s12249-021-02091-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/08/2021] [Indexed: 12/02/2022] Open
Abstract
This study evaluates the potential use of near-infrared hyperspectral imaging (NIR-HSI) for quantitative determination of the drug amount in inkjet-printed dosage forms. We chose metformin hydrochloride as a model active pharmaceutical ingredient (API) and printed it onto gelatin films using a piezoelectric inkjet printing system. An industry-ready NIR-HSI sensor combined with a motorized movable linear stage was applied for spectral acquisition. Initial API-substrate screening revealed best printing results for gelatin films with TiO2 filling. For calibration of the NIR-HSI system, escalating drug doses were printed on the substrate. After spectral pre-treatments, including standard normal variate (SNV) and Savitzky-Golay filtering for noise reduction and enhancement of spectral features, principal component analysis (PCA) and partial least squares (PLS) regression were applied to create predictive models for the quantification of independent printed metformin hydrochloride samples. It could be shown that the concentration distribution maps provided by the developed HSI models were capable of clustering and predicting the drug dose in the formulations. HSI model prediction showed significant better correlation to the reference (HPLC) compared to on-board monitoring of dispensed volume of the printer. Overall, the results emphasize the capability of NIR-HSI as a fast and non-destructive method for the quantification and quality control of the deposited API in drug-printing applications.
Collapse
|
10
|
Yamamoto E, Takeda Y, Ando D, Koide T, Amano Y, Miyazaki S, Miyazaki T, Izutsu KI, Kanazawa H, Goda Y. Discrimination of ranitidine hydrochloride crystals using X-ray micro-computed tomography for the evaluation of three-dimensional spatial distribution in solid dosage forms. Int J Pharm 2021; 605:120834. [PMID: 34192587 DOI: 10.1016/j.ijpharm.2021.120834] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/22/2021] [Accepted: 06/24/2021] [Indexed: 11/19/2022]
Abstract
A non-destructive discrimination method for crystals in solid dosage drug forms was first developed using a combination of Raman spectroscopy and X-ray micro-computed tomography (X-ray CT). Identification of the crystal form of an active pharmaceutical ingredient (API) at the appropriate pharmaceutical dosage is crucial, as the crystal form is a determinant of the quality and performance of the final formulation. To develop a non-destructive analytical methodology for the discrimination of solid API crystals in a solid dosage form, we utilized a combination of Raman spectroscopy and X-ray CT to differentiate between ranitidine crystal polymorphs (forms 1 and 2) in tablet formulations containing three excipients. The difference in electron density correlated with the true density between ranitidine polymorphs, thereby enabling the discrimination of crystal forms and visualization of their three-dimensional spatial localization inside the tablets through X-ray CT imaging. Furthermore, X-ray CT imaging revealed that the crystal particles were of varying densities, sizes, and shapes within the same batch. These findings suggest that X-ray CT is not only an imaging tool but also a unique method for quantitative physicochemical characterization to study crystal polymorphs and solid dosage forms.
Collapse
Affiliation(s)
- Eiichi Yamamoto
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan.
| | - Yoshihiro Takeda
- Core Technology Research Department, X-ray Research Laboratory, Rigaku Corporation, 3-9-12, Matsubara-cho, Akishima, Tokyo 196-8666, Japan
| | - Daisuke Ando
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Tatsuo Koide
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Yuta Amano
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan
| | - Shingo Miyazaki
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan
| | - Tamaki Miyazaki
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Ken-Ichi Izutsu
- Division of Drugs, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| | - Hideko Kanazawa
- Faculty of Pharmacy, Keio University, 1-5-30, Shibakoen, Minato-ku, Tokyo 105-8512, Japan
| | - Yukihiro Goda
- National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-9501, Japan
| |
Collapse
|
11
|
|
12
|
Blaney G, Donaldson R, Mushtak S, Nguyen H, Vignale L, Fernandez C, Pham T, Sassaroli A, Fantini S. Dual-Slope Diffuse Reflectance Instrument for Calibration-Free Broadband Spectroscopy. APPLIED SCIENCES (BASEL, SWITZERLAND) 2021; 11. [PMID: 35719895 PMCID: PMC9204805 DOI: 10.3390/app11041757] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This work presents the design and validation of an instrument for dual-slope broadband diffuse reflectance spectroscopy. This instrument affords calibration-free, continuous-wave measurements of broadband absorbance of optically diffusive media, which may be translated into absolute absorption spectra by adding frequency-domain measurements of scattering at two wavelengths. An experiment on a strongly scattering liquid phantom (milk, water, dyes) confirms the instrument’s ability to correctly identify spectral features and measure absolute absorption. This is done by sequentially adding three dyes, each featuring a distinct spectral absorption, to the milk/water phantom. After each dye addition, the absorption spectrum is measured, and it is found to reproduce the spectral features of the added dye. Additionally, the absorption spectrum is compared to the absorption values measured with a commercial frequency-domain instrument at two wavelengths. The measured absorption of the milk/water phantom quantitatively agrees with the known water absorption spectrum (R2 = 0.98), and the measured absorption of the milk/water/dyes phantom quantitatively agrees with the absorption measured with the frequency-domain instrument in six of eight cases. Additionally, the measured absorption spectrum correctly recovers the concentration of one dye, black India ink, for which we could accurately determine the extinction spectrum (i.e., the specific absorption per unit concentration). The instrumental methods presented in this work can find applications in quantitative spectroscopy of optically diffusive media, and particularly in near-infrared spectroscopy of biological tissue.
Collapse
|