Rotavirus detection using ultrasound enhanced latex agglutination and turbidimetry

Application of a non-cavitating ultrasonic standing wave to suspended micro particles brings the particles into close approximation and has been used p reviously to enhance the performance of several diagnostic agglutination te sts. The sensitivity of rotavirus detection by ultrasound enhanced latex ag glutination was compared with conventional test-card agglutination. Applica tion of ultrasound gave a 32-fold improvement in the sensitivity of detecti on of rotavirus antigen in buffer compared with the test card method. A nov el turbidimetric approach was used to measure agglutination occurring follo wing the test-card procedure (in place of visual examination) and following exposure of commercial rotavirus latex reagents to a 4.5 MHz ultrasonic fi eld (in place of microscopy). The sensitivity enhancement over the conventi onal method achievable through ultrasonic exposure was comparable whether a gglutination measurements were made visually or turbidimetrically and demon strates the potential for turbidimetry in combination with the ultrasonic m ethod. Turbidimetry offers an alternative to visual assessment that may be more easily incorporated into automated systems.