Abstract:
A method for detecting and counting particles suspended in fluids, such as bacteria suspended in urine, utilizing dynamic features of the suspended particles and employing light scattering measurements. The disclosed method is suitable for determining the susceptibility of bacteria to antibiotics. A cuvette for detecting bacteria in fluids, which is especially suited for the light scattering measurements, is provided.
Abstract:
Un método para recuento de bacterias suspendidas en un fluido, en que una porción de dicho fluido se filtra para excluir partículas mayores que dichas bacterias y una muestra de la porción filtrada se pone en una cubeta que tiene al menos una ventana iluminada con un haz de luz coherente y colimado, comprendiendo el método las etapas de: i. medir repetidamente a una velocidad de repetición predefinida la intensidad de luz dispersada por la muestra a al menos dos ángulos diferentes de dispersión, ii. calcular representaciones gráficas de diferencia de las mediciones de intensidad de la luz a cada uno de los diferentes ángulos de dispersión a los que se mide la intensidad de la luz, comprendiendo cada representación gráfica de diferencia los valores absolutos de diferencias entre niveles de intensidad de luz medidos en dos momentos de tiempo o diferentes al mismo ángulo de dispersión y iii. igualar cada una de dichas representaciones gráficas de diferencia con una curva de calibración para proporcionar una estimación de la concentración de las bacterias en la muestra.
Abstract:
System and method for detecting and counting bacteria suspended in a biological fluid by means of light scattering measurements is provided. In accordance with the method of the invention the level of signal to noise of the measured intensities of light scattered by a sample of the biological fluid is significantly enhanced for forwardly scattered light within a range of scattering angles which are smaller compared to a predefined maximal scattering angle. The system of the invention includes a cuvette adapted to contain a sample of the biological fluid whose sidewalls and windows are suitably constructed and arranged to significantly reduce the level of reflected light obscuring the scattering patterns measured within the range of scattering angles considered.
Abstract:
A method for detecting and counting particles 12 suspended in fluids, such as bacteria suspended in urine, utilizing dynamic features of the suspended particles and employing light scattering measurements. The disclosed method is suitable for determining the susceptibility of bacteria to antibiotics. A cuvette 14 for detecting bacteria in fluids, which is especially suited for the light scattering measurements, is provided.
Abstract:
A method for detecting and counting particles suspended in fluids, such as bacteria suspended in urine, utilizing dynamic features of the suspended particles and employing light scattering measurements. The disclosed method is suitable for determining the susceptibility of bacteria to antibiotics. A cuvette for detecting bacteria in fluids, which is especially suited for the light scattering measurements, is provided.
Abstract:
System and method for detecting and counting bacteria suspended in a biological fluid by means of light scattering measurements is provided. In accordance with the method of the invention the level of signal to noise of the measured intensities of light scattered by a sample of the biological fluid is significantly enhanced for forwardly scattered light within a range of scattering angles which are smaller compared to a predefined maximal scattering angle. The system of the invention includes a cuvette adapted to contain a sample of the biological fluid whose sidewalls and windows are suitably constructed and arranged to significantly reduce the level of reflected light obscuring the scattering patterns measured within the range of scattering angles considered.