Itsy-bitsy things

The first item—“A Glimpse at the Future of DNA: M.D.’s Inside the Body”(and thanks to Eric Smith for the tip)—is about using DNA sections to encode a sequence of events that might identify a specific molecular maker for a cancer and then trigger a therapeutic response. That’s interesting, but if you couple it with the second item—“UCLA chemists develop new coating for nanoscale probes”—you might really have something. The UCLA people found a way to disguise the outer coat of inorganic molecules with proteins that would allow them to sneak through the outer membrane of a cell—Trojan horse-like—and deliver a payload inside. Put the two things together and it looks like parts of a molecular detection and delivery system. Don’t hold your breath, but the beginnings are there.

A Glimpse at the Future of DNA: M.D.’s Inside the Body

Scientists have developed what they say could become the world’s smallest medical kit: a computer, made of DNA, that can diagnose disease and automatically dispense medicine to treat it. The computer, so small that one trillion would fit into a drop of water, now works only in a test tube, and it could be decades before something like it is ready for practical use. But it offers an intriguing glimpse of a future in which molecular machines operate inside people, spotting diseases and treating them before noticeable symptoms even appear.

The computer is made of double-stranded DNA with ends that are single-stranded. These so-called sticky ends can bind to specific other strands of DNA or RNA in the solution under the usual rules of DNA pairing. If binding occurs, the enzyme cuts the DNA a certain distance away, exposing new sticky ends. If those ends find something to bind to, the enzyme cuts in yet another location, and so on. If the chain reaction proceeds in a certain way, the enzyme eventually slices off the piece of DNA that acts as the drug.

UCLA chemists develop new coating for nanoscale probes

A UCLA-led team of chemists has developed a unique new coating for inorganic particles at the nanoscale that may be able to disguise the particles as proteins — a process that allows particles to function as probes that can penetrate the cell and light up individual proteins inside, and create the potential for application in a wide range of drug development, diagnostic tools and medications.