Sometimes the advantage of using one instrument over another lies not just in the the instrument’s capabilities, but also in other, more practical, factors such as time and cost of operation. This is especially true in clinical studies, where time and money play a crucial role in determining not only a given day’s workload, but also the number of patients diagnosed per day. For instance, instruments that return timely results not only decrease patient wait-time, but they also increase the number of patients that could benefit from research each day.
If an instrument's operating costs are low, then it not only increases the number of patients who can afford diagnostic procedures, but it also increases the amount of funds available to be spent on other diagnostic needs. Surface plasmon resonance (SPR) is being used to help diagnose a wide range of conditions and other health problems in both clinical and laboratory settings, with applications ranging from prostate cancer detection to the detection of bacterial infections.
With the exception of skin cancer, prostate cancer affects more American men than any other type of cancer, with over 180,000 new cases each year. Such a high rate of incidence leads to over 26,000 fatal cases each year in the United States alone. Currently, the method of choice to diagnose this condition is ELISA, which requires a relatively higher cost of operation and longer analysis time than SPR. Improved performance of SPR biosensors in detecting PSA levels by using imprinted biosensors, has resulted in experimental studies with a 98% agreement with ELISA data at lower cost per analysis.
These imprinted biosensors have multiple advantages over those of traditional SPR biosensors. They possess ultrasensitive detection levels without using gold or silver nanoparticles as signal amplifiers. Further, detection of PSA antigen levels can be performed in real time. Additionally, the microcontact imprinted biosensors are cheap, reusable and have a long shelf life; making these sensors an excellent choice as cost-effective diagnostic tools. It should come as no surprise that this methodology is gradually becoming a favored technique.
SPR is also gaining traction in laboratory bacterial analyses. Strains such as E. coli, S. Aureus, and P. aeruginosa are known for being root causes of common infectious diseases. As such, they are of great interest to the scientific community. SPR techniques have been used in ultra-sensitive detection of E. coli and S. aureus strains. Ongoing studies are being performed to detect S. aureus and P. aeruginosastrains amidst a host of other bacteria using SPR to detect the toxins secreted by the bacteria, creating a powerful tool for characterizing bacterial colonies.
SPR is not only useful in clinical settings for the monitoring of PSA levels, but it is also useful in the laboratory for detecting the presence of several strains of harmful bacteria. As more biosensor studies are published year after year, researchers continue to gain insights into the practical application of the technology.