Featured journals publishing the latest academic research Journals listed are from all publishers, including Wiley. Wiley Online Library: connecting the global. Peaberry coffee discrimination using UV-visible spectroscopy Journal of Pharmaceutical and Biomedical Analysis , 19, – International Journal of Institutional Pharmacy and Life Sciences 5(5): Thus, for a fixed path length, UV/VIS spectroscopy can be used to.


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Further, there is clear evidence that there are important interactions between the invading tumor cells and stromal cells that allow tumor proliferation, invasion, metastasis and malignant transformation [ 16 ].

These interactions are expected to cause significant changes in the organization and arrangement of the extracellular matrix surrounding the neoplasm. In MRI, the measured apparent diffusion coefficient ADC of water in tissue can provide information regarding tissue structure by imaging water content in intra- and extra-cellular space, which in turn can be used to assess cell death occurring via necrosis or apoptosis [ 1718 ].

Uv-vis spectroscopy journal spectroscopy Methods of optical science and engineering uv-vis spectroscopy journal been developed for cancer detection and diagnosis and more recently to assess response to therapy in a variety of tissue sites for applications in both pre-clinical and clinical studies [ 19 - 27 ].


The interaction of light with complex media such as biological tissues, is characterized by processes that depend on the physical nature of the light and the specific tissue morphology and composition [ 2829 ].

The incident light can be scattered elastically or inelastically multiple times due to microscopic differences in the index of refraction of cells and subcellular uv-vis spectroscopy journal within the tissues, and may be non-radiatively absorbed by chromophores present in the medium or by fluorophores, which release their excess energy by radiative decay, producing fluorescence.

The remitted fluorescent light can, uv-vis spectroscopy journal turn, be multiply scattered or absorbed.

Journal of Formulation Science & Bioavailability

Although complex, these optical responses can be measured by a variety of spectroscopic techniques and processed through rigorous computational or theoretical models to obtain quantitative uv-vis spectroscopy journal and morphological information about the tissues [ 30 - 32 ].

In optical spectroscopy, the wavelengths of illumination span the ultraviolet UV through the near-infrared NIR wavelengths.

In steady-state reflectance spectroscopy, a broadband light source is used for illumination and a spectrum of the reflected light is collected [ 33 ], while in steady-state fluorescence spectroscopy a narrow spectral-band of incident light obtained via filtering a broadband source or from a narrowband laser is used to excite fluorophores and the emerging fluorescence spectrum uv-vis spectroscopy journal each excitation wavelength is detected [ 34 ].

The diffuse reflectance spectrum is a function of the optical uv-vis spectroscopy journal and scattering coefficient spectra [ 28 ].


The absorption and scattering coefficients are wavelength dependent and their value uv-vis spectroscopy journal each wavelength reflects the probability that a photon of given wavelength will be absorbed or scattered by the tissue when it traverses an infinitesimal step within the medium.

The shape and magnitude of the absorption coefficient depends on the extinction coefficient and concentrations, respectively of dominant tissue chromophores which include uv-vis spectroscopy journal hemoglobin HbO2 and deoxygenated hemoglobin Hbbeta carotene, water and lipids in the UV-NIR spectrum [ 3536 ].

The optical scattering coefficient is known to be sensitive to the spatial architecture and organization of the tissue and therefore can be used as a means to quantify cellular morphology and structure [ 37 - 39 ].

The shape and magnitude of the intrinsic fluorescence spectrum depends on the concentrations of the tissue fluorophores, which include several important biochemical molecules such as nicotinamide adenine dinucletide NADH and flavin adenine dinucleotide FAD or structural proteins such as collagen, elastin and keratin [ 40 uv-vis spectroscopy journal 42 ].

The ratio uv-vis spectroscopy journal NADH to FAD is called the optical reduction-oxidation redox ratio and can provide information about the reduction-oxidation state in the electron transport chain within the mitochondria. The optical redox ratio has been shown to increase with a decrease in cellular oxygenation [ 4344 ].

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Measurement of endogenous fluorescence could also provide a means to sense changes in the extracellular matrix composition. Uv-vis spectroscopy journal, the measured fluorescence spectrum can be significantly distorted by tissue absorption and scattering and needs to be corrected to get the intrinsic, uv-vis spectroscopy journal fluorescence spectrum which can then be used to quantify either absolute or relative tissue fluorophore contributions [ 34 ].

The uv-vis spectroscopy journal depth of light varies from several millimeters in the UV-visible spectrum to several centimeters in the NIR region [ 45 ].

In the UV-visible region, tissues are absorption dominant, which restricts the penetration depth. With increasing wavelength, the overall absorption coefficient decreases and the ratio of scattering to absorption coefficients increase.

Thus, in the red and NIR wavelengths tissues are more transparent and photons can migrate through several centimeters of tissue which allows NIR spectroscopy to interrogate sub-surface solid tumors such as those in the breast and neck nodes.


UV-visible spectroscopy complementarily has a superficial sensing depth and can directly interrogate pre-cancerous growth and primary invasive carcinomas in the head and neck, anus, cervix, and recurrent chest wall disease in breast cancer.

Optical spectroscopic probes can also be guided through endoscopes and biopsy needles to access uv-vis spectroscopy journal within body cavities as in breast cancers.

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