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Optical Spectroscopy for the Detection of Necrotizing Enterocolitis
Published in David J. Hackam, Necrotizing Enterocolitis, 2021
Optical spectroscopy is a technology that has shown potential promise in this regard and merits more widespread understanding and investigation. Spectroscopy is a measurement of the interaction of electromagnetic radiation, or light, with tissue. The electromagnetic spectrum is the range of wavelengths and respective frequencies that light waves can manifest, spanning the following commonly known energies from lowest to highest: radio, microwave, infrared, visible (400–700 nm wavelength), ultraviolet, x-ray, and gamma (Figure 20.1). Whenever photons (the basic building blocks of electromagnetic radiation that have properties of both a particle and a wave) encounter an object, various fractions of the light are simultaneously reflected, absorbed, and scattered (Figure 20.2). The proportion of each of these fractions varies by wavelength and is determined by the characteristics of the target and its tendency to interact with each respective wavelength. A spectrophotometer is a device that quantifies this interaction by detecting the fraction of light that is either transmitted (i.e., not absorbed) or reflected. Spectrophotometers are widely used in a diverse array of scientific fields to characterize objects of interest, including physics, astronomy, materials science, chemistry, and biochemistry.
Current Perspectives and Methods for the Characterization of Natural Medicines
Published in Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg, Promising Drug Molecules of Natural Origin, 2020
Muthusamy Ramesh, Arunachalam Muthuraman, Nallapilai Paramakrishnan, Balasubramanyam I. Vishwanathan
The spectroscopical method of compound detection and isolation is due to the interaction between matter with light/electromagnetic radiation. UV-Vis spectroscopy, infrared spectroscopy, NMR, and mass spectrometry are employed to characterize the bioactive constituents of nature. The spectrum of compounds has atoms/molecules and can fragment under certain conditions. Spectral graph of absorbed and emitted radiation and frequency and wavelength helps to detect the compounds. A spectrophotometer is an instrument employed to obtain the spectrum.
Modelling and analysis of skin pigmentation
Published in Ahmad Fadzil Mohamad Hani, Dileep Kumar, Optical Imaging for Biomedical and Clinical Applications, 2017
Ahmad Fadzil Mohamad Hani, Hermawan Nugroho, Norashikin Shamsudin, Suraiya H. Hussein
A spectrophotometer is a combination of a spectrometer and a photometer (Figure 4.28). Spectrometer refers to a light radiation system and photometer is a photon conversion system into an electrical (digital) signal. In a spectrophotometer, a prism or similar optical equipment is located between spectrometer and photometer and used to disperse the re-emitted light from the skin into numerous bands (Figure 3.8).
Comparison of tiotropium delivery with the ODAPT adapter and a valved holding chamber
Published in Canadian Journal of Respiratory, Critical Care, and Sleep Medicine, 2021
Rym Mehri, Abubakar Alatrash, Nicholas Ogrodnik, Kenny Lee Slew, Edgar A. Matida
The experimental setup was then disassembled and washed separately to quantify the amount of medication deposited within each component. All the different components were washed using distilled water to dissolve the medication. The ACI deposition plates were placed into separate Petri dishes with 15 mL of distilled water and were shaken for 1 minute each. The face, facemask, and ODAPT adapter (for test case 3 and 4) were carefully cleaned with 10 mL, 10 mL and 8 mL of distilled water, respectively. The induction port (IP) only (for test case 1 and 2) or the IP and the tubing coupler (for the test case 3, 4, 5 and 6) were washed with 15 mL of distilled water. For test case 5 and 6, the VHC was washed using 25 mL of distilled water. Each component was left in their respective solution for 2 hours to allow for a consistent dissolution of the medication. Spectrophotometry was used to obtain the concentration of each solution at 237 nm (8453 UV-Visible Spectrophotometer, Agilent Technologies, Santa Clara, CA). Further details on the spectrophotometry methodology are provided in Mehri et al.15 Three repeats of each test were performed.
Effect of casting solvent, film-forming agent and solubilizer on orodispersible films of a polymorphic poorly soluble drug: an in vitro/in silico study
Published in Drug Development and Industrial Pharmacy, 2019
Ahmed Abd El-Bary, Ibrahim Al Sharabi, Balqees Saeed Haza'a
Dissolution studies were carried out according to the USP dissolution II paddle method using a dissolution tester (Vision® Classic 6TM Dissolution Tester, Hanson Research Corporation, California, USA) using 900 mL of 0.1 N HCl as a dissolution medium. The rotation speed was 50 rpm and the temperature was kept at 37 ± 0.5 °C. A 5-mL sample was withdrawn and replaced with fresh dissolution media at specified time intervals. The collected samples were filtered through 0.45 μm Millipore filter papers to be analyzed for piroxicam content at 333 nm using the UV/Vis. Spectrophotometer. Stainless steel mesh with sieve opening of about 1 mm was used to dip the tested films inside the dissolution medium. All experiments were conducted in triplicate, and mean values ± SD were calculated. Percentages of drug released from the films were plotted as a function of time.
Spectrophotometric Analysis of Different Polymethyl Methacrylate Filters and their Importance in the Implantation of Corneal Rings
Published in Current Eye Research, 2023
Pablo Felipe Rodrigues, Bernardo Kaplan Moscovici, Juliana Lopes Hoehne, Mauro Silveira de Queiroz Campos, Andreia de Araújo Morandim-Giannetti, Patrícia Alessandra Bersanetti, Walton Nosé
Spectrophotometry is a measurement technique widely used in many natural and human sciences fields.12 The reflectance spectrophotometer measures the intensity of the reflected light compared to the light intensity of a reference through the material analyzed’s absorbance, reflection, and transmittance.13,14 This principle determines the amount of light reflected, absorbed, and transmitted by material in all spectra, from the visible ultraviolet to the near-infrared. The standard refers to the “estimation of uncertainty about test results derived from spectrophotometry,” subdivided into instrument, operator, and uniformity-uncertainty contributions, which can be considered a guideline for this analysis.13,14