UNM engineering - School of Engineering - University of New Mexico

One Bead, Two InnovationsTwo sides of campus, two disciplines, two goals, one sharedinterest: microscopic beads. Gabriel Lopez and Larry Sklar,professor of pathology at UNM’s School of Medicine, arecollaborating on fluorescent biosensors that use tiny, proteincoatedbeads the size of a human cell. While their researchgoals are different, it’s a strategic collaboration because theresearchers share an interest in the microbiosensors andin biochemistry. “It’s technically a natural fit and our workis nicely complementary,” says Lopez. The two researchers,along with Tione Buranda, research assistant professor inthe Pathology Department, have shared a series of five-yeargrants during their twelve-year collaboration.Sklar uses the beads for drug discovery, coating them with aspecific protein and suspending them in a fluid that he wantsto test. By running the suspension through a flow cytometer,Sklar can evaluate the reaction of the proteins on the surfaceof the beads with those in the solution. Using this process,Sklar and Buranda can screen molecules involving more thana dozen molecular interactions that contribute to cancer,infectious diseases, and inflammatory diseases. Sklar sayscollaborating with engineers at the CBME moves the teamcloser to its goals. “An engineer’s skill set is complementaryto those of a biomedical scientist,” he explains. “One of thebiggest factors is the different types of materials that weuse for building sensors or instrumentation. Engineeringstudents have different interests in technology thanbiologists, including materials, fluidics, automation,electronics, and computers.”Lopez and his team use the beads to create diagnosticassays. They make chip-based, microfluidic devices bypacking thousands of the protein-coated beads into tiny glasscapillaries. Lopez injects a fluid, for example a blood sample,into the bead-packed channels. When he exposes the channelsto a laser, the beads that are attached to specific proteinsfluoresce, indicating the presence of a toxin or diseasemarker in the liquid. Lopez and his team are currently testingsuch devices, using samples from patients with respiratoryinfections. The devices have already successfully detectedseveral different viruses in one small sample. dTione Buranda, research assistant professor in thePathology Department and Gabriel Lopez, directorof the CBME and professor of chemical and nuclearengineering and chemistry, have shared a series of fiveyeargrants during their twelve-year collaboration.Above: Confocal scanning laser fluorescencemicroscopy image of mesoporous silica particlesfilled with rhodamine dye (red) and encapsulatedby fluorescent lipid bilayer (green). Bottomimage shows one particle (arrow) which hasbeen partially bleached for measurements ofdiffusive fluorescence recovery.UNM Engineering 09