Basic Research - Cancer(구연) (NP-007) 전기임피던스 스펙트로스코피 니들을 이용한 정상 신 조직 및 악성 신종양 조직의 구분 ¹부산대학교 의학전문대학원 비뇨기과학교실 ²광주과학기술원 의생명공학과 김현우¹, 윤조호², 김경환¹, 강병진¹, 이경¹, 백승룡¹, 박지훈¹, 신동길¹, 이종현², 이정주¹ Objective: Electrical impedance spectroscopy (EIS) added on a hypodermic needle can analyze the impedance (consist of magnitude and phase angle) of tissues in the frequency domain. In this study, an EIS-on-a-Needle (EoN) was proposed for real-time discrimination between normal and cancerous renal tissues. Materials and methods: EoN was fabricated by adding an electrical sensor at the tip of a 22-guage hypodermic needle using photolithography technology in a semiconductor process. To evaluate the efficacy of EoN in discriminating between normal and cancerous renal tissues, three nephrectomy kidney specimens with clear cell carcinoma was prepared. EoN was inserted 2 mm deep into the normal and tumor tissue of each specimen and the electrical impedance of the tissues were measured over the frequency range from 100 Hz to 1 MHz at an operating voltage of 200 mVrms. The mean of magnitude and phase angle from the three specimens at each frequency were compared between the normal and tumor tissues to evaluate the effectiveness of EoN. Results: The normal and tumor tissues were apparently discriminated by the mean magnitude and phase angle at the frequency range from 200 kHz to 1 MHz. The largest difference was observed at 630 kHz and 200 kHz for mean magnitude and phase angle, respectively. The mean impedance values of the normal tissues were tended to be larger than those of the tumor tissues at the frequency range from 200 kHz to 1 MHz. Conclusion: EoN could apparently discriminate between normal and cancerous renal tissues at the frequency range from 200 kHz to 1 MHz. Further studies using a larger number of specimens are essential for a precise evaluation of EoN in tissue discrimination. keywords : Impedance, Kidney, Cancer