An innovative kind of sensor has been developed by scientists that functions like Velcro® for prostate cancer cells and sticks them to a modified frosted glass slide, such as those used in science classes, enabling them to be identified from blood samples. The low-cost technique, described in ACS Applied Materials & Interfaces, could assist doctors in diagnosing and monitoring the disease in a better way.
In men suffering from prostate cancer, certain tumor cells leave the prostate gland and circulate in the blood. When these cells are detected, it could help in diagnosing the disease at an earlier stage or assist doctors in evaluating whether treatment is effective. Yet, since there exist very few circulating tumor cells, detecting them could turn out to be difficult. Earlier sensor models have been costly and challenging to manufacture. Therefore, Shudong Zhang and Shutao Wang aspired to devise a highly cost-efficient and simpler way to monitor prostate cancer cells in the blood.
The device designed by the scientists was based on frosted glass microscope slides, commonly used in high-school science classes. The frosted area, used to hold and label the slide, is a sandblasted surface that has minute depressions. The scientists added a solution to the frosted slides that led to the growth of silica nanowires on their surfaces. Then, they suspended antibodies with the ability to detect prostate cancer cells from the nanowires.
Once the circulating tumor cells are captured by the antibodies, they get trapped in the depressions on the slide and suspended inside the nanowires, analogous to the interlocking surfaces of Velcro®. The researchers were then able to observe the cancer cells using microscopy and discovered that the capture efficiency of the device was equivalent to that of other approaches. Upon testing blood samples from prostate cancer patients, the researchers found that the device detected as less as 10 tumor cells in 1 mm of blood.
Funding from the National Natural Science Foundation, the Beijing Municipal Science and Technology Commission, the Top-Notch Young Talents Program of China, and the Youth Innovation Promotion Association is acknowledged by the authors.