A novel therapeutic instrument using an ultrasound-light-emitting diode with an adjustable telephoto lens for suppression of tumor cell proliferation

•Proposing therapeutic instrument using an ultrasound-LED with adjustable telephoto lens.•Providing an adjustable therapeutic target area (≤1 cm2).•Decreasing the tumor cells growth rate. A new therapeutic instrument using ultrasound and a light-emitting diode with an adjustable optical lens was introduced for suppressing HeLa cell proliferation. A focused-type ultrasonic transducer can transmit an acoustic signal to focus the ultrasound signal onto a certain spot. Likewise, the light-emitting diode light is noncoherent and divergent, and therefore, a telephoto lens is also needed to focus light on certain desired areas. This combinational instrument, which provides an adjustable focus for the transmitted light, could be useful for differentiating the treatment and nontreatment ranges when utilizing light-emitting diodes and ultrasound sources as treatment devices. The telephoto lens can provide an adjustable illumination area of 7.06 mm × 4.01 mm and 14.05 mm × 11.67 mm in focus and defocus modes, respectively, and ultrasound can also provide adjustable acoustic beam diameters of 7 mm and 14 mm at the −6 dB intensity levels, respectively. The developed therapeutic instrument was tested to demonstrate that HeLa cell proliferation was suppressed with the ultrasound-light-emitting diode controlled by a telephoto lens. Owing to the mechanical and thermal effects caused by the ultrasound and light-emitting diode, the control of cell density by focused and defocused beams on Day 2 is shown as 99.38 ± 0.32%, 51.33 ± 10.89%, and 37.70 ± 1.95%, respectively. Therefore, we confirm that the developed ultrasound-light-emitting diode with an adjustable telephoto lens can suppress the proliferation of HeLa cells.