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1

Determining the optical properties of blood using He-Ne laser and double integrating sphere set-up

Ashoor Habib E., Jasim Khalil Ebrahim

Polish Journal of Medical Physics and Engineering

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2019

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Vol. 25, Iss. 1

1--5

EN

The behaviour of light interaction with biological tissue is determined by micro-optical parameters: refractive index (n), absorption coefficient (µa), scattering coefficient (µs), and anisotropy (g). The goal of this study is to measure the optical properties of normal whole blood using He-Ne laser (wavelength 632.8 nm). The refractive index is measured using the traveller microscope. The integrating sphere method is used to measure the macro-optical parameters: total diffusive reflectance, transmittance, and collimated transmittance at wavelength 632.8 nm. The macro-optical parameters are fed to Inverse Adding Doubling (IAD) theoretical technique, to estimate the micro-optical parameters (µs, µa, g). An alternative practical method is used to measure the g value based on utilising the goniometric table. The study reveals that the refractive index (n) equals 1.395±0.0547, absorption coefficient (µa) equals 2.37 mm−1, scattering coefficient (µs) equals 55.69 mm−1, and anisotropy (g) equals 0.82. In conclusion, these findings approved, in general, the applicability of the suggested experimental set up. The set up depend on using three devices: the integrating sphere method to estimate (µs, µa, g), traveller microscope (n) and goniometer (g).

2

Selective RP-HPLC method for determination of quetiapine in presence of coadministered drugs: Application for long-term stability study of quetiapine in whole blood

Youssef R. M., Abdine H., Barary M. A., Wagih M. M.

Acta Chromatographica

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2016

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Vol. 28, no. 3

263--279

EN

Incidence of suicidal attempts presents an explanation for the high prevalence of quetiapine (QTI) in forensic cases. Thus, the interpretation of its concentrations in biological specimens is needed, but in forensic toxicology, potential postmortem changes such as instability of the target drugs should be taken in consideration. High-performance liquid chromatography (HPLC) method has been developed for determination of QTI. This method was based on reversed phase (RP)-HPLC separation of QTI on a C-18 column (150 mm × 4.6 mm, 5 μm) with elution system of acetonitrile—methanol—0.025 M phosphate buffer (pH 2.5), containing 1 mL TEA in each 250 mL, in a ratio of 40:30:30%, v/v, at the flow rate of 1.2 mL min−1 using mirtazapine as internal standard (IS). The proposed method was applied to the determination of QTI in plasma in presence of coadministered drugs. The application of the proposed method was extended for long-term stability study of two different concentration levels of QTI in the whole blood.

3

Major, minor, and trace elements in whole blood of patients with different leukemia patterns

Khuder A., Bakir M. A., Solaiman A., Issa H., Habil K., Mohammad A.

Nukleonika

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2012

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Vol. 57, No. 3

389-399

EN

The elemental sensitivity method for X-ray fluorescence analysis was applied to determine S, Cl, K, Ca, Fe, Cu, Zn, Br, and Rb in the whole blood of leukemia patients and healthy volunteers. Leukemia samples were classified according to type, growth, and age of participants. Student’s t-test results showed that, the mean concentration of the studied elements was significantly lower in leukemia patients than that in controls. Strong mutual correlations (r greather than 0.50) in the whole blood of leukemia patients were observed between S-Ca, K-Fe, K-Ca, Fe-Zn, K-Zn, K-Rb, Fe-Rb, Zn-Rb, S-Cl, S-K, Ca-Fe, Cl-Ca, and Ca-Rb; whereas, S-K, S-Ca, S-Cl, Cl-K, Cl-Ca, Fe-Zn, Zn-Rb, Fe-Rb, K-Fe, and Zn-Br exhibited strong relationships (r greather than 0.50) in the whole blood of controls, all were significant at p less than 0.05. Significant differences between grouping of studied elements in the control group and all classified leukemia groups, except younger age-group, were obtained using principal component analysis. The study indicated appreciably different patterns of element distribution and mutual relationships in the whole blood of leukemia patients in comparison with controls.

4

Zastosowanie systemu zamkniętego w laboratoriach i pracowniach diagnostycznych

Janik K., Antoniewicz-Papis J.

Laboratorium - Przegląd Ogólnopolski

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2012

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nr 9-10

34--36

PL

Praca z materiałem biologicznym musi odbywać się w sposób zapewniający bezpieczeństwo zarówno materiału biologicznego, pacjentów oraz personelu laboratorium. Ważne jest wykorzystanie technik umożliwiających zachowanie odpowiedniej jakości pobieranego materiału. Niewątpliwie do takich technik należy system zamknięty, który umożliwia utrzymanie sterylności materiału podczas transportu, wykonywania badań, przechowywania itp. Zastosowanie tego systemu wymaga użycia specjalnego sprzętu, ale jednocześnie pozwala na uzyskanie korzyści związanych z bezpieczeństwem i jakością materiału biologicznego.

EN

Biological material must be handled in a way that ensures its own safety as well as the safety of the laboratory personnel and patients. It is important to rely on techniques that help to maintain the quality of collected material. One of such obvious techniques is the closed system that ensures the sterility of material during transport, testing, storage, etc. This system requires special equipment, but the benefi ts in terms of safety and quality of biological material are indisputable.

5

Modeling of light transmittance measurement in a finite layer of whole blood - a collimated transmittance problem in Monte carlo simulation and diffusion model

Mroczka J., Szczepanowski R.

Optica Applicata

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2005

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Vol. 35, nr 2

311-331

EN

The paper presents the modeling of transmittance measurement in a finite layer of whole blood. To describe light propagation in whole blood medium, a Monte Carlo simulation was used. The propagation of light in whole blood medium in the model required the assumption of photon transport approximation in highly scattering media. We have analyzed collimated-diffuse transmittance, which depended on the technique of free path length simulation. The Monte Carlo simulation was compared with the diffusion model designed for a finite incident light beam and available measurement data of whole blood optical density. The research revealed that discrepancy between the models discussed may be attributed to inaccuracy of the diffusion model due to an increase of anisotropic radiance under the thin sample conditions. Moreover, comparison of the Monte Carlo simulation versus measurement data showed that adding off-sets enabled agreement between them for hematocrit up to 60-70%, which is sufficient for many applications in oximetry. In fact, discrepancy in the Monte Carlo simulation, requiring off-sets to fit measurement data, most likely originates from measurement problem, such as divergence of light source or perturbation of light beam.