Depending on what a test is looking for, getting results from a blood test can take anywhere from an hour to a week. The same holds true for examinations of food and water contamination. The majority of the time, lengthy procedures in sample processing and analysis are what cause the delay. In a popular class of magnetic beads, MIT engineers have now discovered a novel optical signature that might be utilized to quickly detect impurities in various diagnostic procedures. For example, the team showed the signature could be used to detect signs of the food contaminant Salmonella. The so-called “Dynabeads”