“This,” he said as he tapped the box, “can replace them. Squeeze a BSL-4 lab down to a room six inches long, four inches wide, and two inches tall. Less than a thousand dollars, total cost.”
Vlad picked up a glass slide. He handed it to Becraft. “Spit,” he said.
“On the slide? Why?”
“Humor me.”
Becraft spit on the slide. Vlad took it and placed it under a microscope hooked up to a video monitor. “Let’s say I worry you have smallpox virus. What do I do? I have you spit on slide. Then I put NEWTON to work.”
Vlad put the NEWTON box near the glass slide, then took out a laser pointer and his BlackBerry and started working the keys. As they watched, a little door opened on the front of the NEWTON box. A Crawler skittered out and ran across the table. Becraft took a half-step back.
“It’s controlled by microwave signal,” Jake said. “Basically like a cellphone, but working at a different frequency.” Vlad aimed the laser pointer at the Crawler. A red dot appeared on the table. The Crawler sensed the beam, ran sideways toward it. It followed the red dot as Vlad moved the beam along the table.
Becraft watched, amazed. “It’s following the light?”
“The heat,” Jake said. “The Crawler has a bolometric heat sensor. It can even pick up the thermal signal given off by your hand.”
Vlad led the Crawler across the Formica bench, up and onto the glass slide. Then he hit a key on his BlackBerry and the Crawler stopped.
The Crawler’s image filled the monitor, enlarged fifty times. The Crawler was supping at Becraft’s spittle like a deer at a stream.
“There you go,” Vlad said. “The Crawler has sample. Now we just send it home.” With his BlackBerry and the laser pointer, he led it back to the box. The door opened, and in it went. “If this were real threat, we could be doing this from the next room. Or next state.”
Vlad picked up the box, placed it under the microscope. “Now it gets interesting.” They watched on the monitor as the Crawler walked in and regurgitated the droplet back up out of its proboscis, creating a cloudy spherical orb of liquid on a transparent piece of plastic. The Crawler retreated to the corner of the box.
Vlad pushed a button, and the droplet was sucked in, down into a tiny tube, disappearing into an array of tiny channels. “Preprocessing,” Vlad said. “Separating DNA from drool.” A minute later, the droplet reappeared on what looked like a shiny field of silver grass, clearer now. Underneath the grass, the outlines of electronic circuitry were dimly visible.
“Our test sample,” Vlad said, gesturing to the nearly perfect orb on the screen. “Droplet is sitting on special computer chip. The surface is array of tiny vertical needles etched in silicon. Each less than one hundred nanometers in diameter. The needles are hydrophobic—water hates them—so droplet floats on surface.”
“It looks like it’s glowing,” Becraft said.
“Fluorescence,” Vlad said. “Dye molecules are in droplet that stick to DNA. Make it glow.”
Vlad adjusted the microscope, and the image zoomed out; the field of grass became a perfectly square miniature lawn. Next to the lawn was a label—fifteen letters etched in silicon: AAACGACTTACGTAT. Vlad zoomed out farther to reveal an array of square lawns, each labeled by a different set of fifteen letters but always a combination of A,C,T, and G, the letters of the genetic alphabet.
Vlad worked his BlackBerry, and the droplet suddenly flattened, penetrating down into the field of needles. “With simple voltage pulse, I make the water droplet stick itself on needles.”
“Vlad the Impaler,” Jake said.
Vlad glanced at Becraft. “He thinks he is clever.” He hit a key on his BlackBerry. “Okay—up!” The droplet was once again a perfect sphere on top of the needles.
“I don’t get it,” Becraft said. “What does this have to do with detecting a biopathogen?”
“The droplet is like a tiny test tube,” Vlad said. “Each patch tests for different pathogen. I make the droplet sit.…” Vlad made the droplet move to the next patch and descend again, impaling itself on the needles. “The needles have oligos bound to it—short strands of single-stranded DNA. Each is a genetic sentence taken from different pathogen. If the DNA in droplet matches the DNA stuck to needles, they bind together. Two single strands of DNA link up to form double helix. If the sequences don’t match, they won’t.” He hit a key, and the droplet popped back up.
The droplet suddenly took off, running along the grassy patches like a crazed mouse in a maze. The watery orb ran to another patch, descended, then popped back up. “We do it over and over, testing for each pathogen,” Vlad said as the droplet ran around on the chip, flattening and popping back up at a dizzying pace.
Becraft pointed to a square. “Wait. That spot is glowing.”
“DNA found a match there. Its complementary strand. It bound to DNA on square like lover, staying behind when droplet went away.”
“And so that square glows.”
Vlad nodded. “It tells you the pathogen.” Vlad checked the sequence written on the chip next to the glowing patch: CACGTGACAGAGTTT. “Hmm. Human parainfluenza virus.”
Becraft stepped back.
Vlad put an arm on his shoulder. “Common cold.”
Becraft said, “What was Connor’s part in all this?”
Vlad nodded. “This chip works with viruses. They are easy—a virus is nothing but genetic material and a protein shell. A few reagents release DNA or RNA, then we run a few steps of PCR to amplify. But bacteria, fungi, they are different. Their genes are locked up inside nucleus, which is inside membrane, which is inside cell wall.”
Jake said, “Connor was developing protocols. Using the Crawlers to collect the samples, slice open the cells, extract the DNA, all the preparatory steps. The gardens of decay were his testing ground. He was teaching Crawlers to conduct every kind of genetic test you might imagine. It was easy for him to adapt his work to this project.”
“And provide advice,” Vlad said. “Say a topic, he’d tell you everything about it. What it linked to. Fungi, bacteria, viruses. The whole history of pandemics, their use as biological weapons.”
Becraft looked to Jake. “I thought you told me Connor didn’t work with anything dangerous.”
“He doesn’t. When you are developing the protocols, you can use anything. Liam worked with whatever benign fungi he happened to be growing in the gardens.”
“So I ask you again. He didn’t work with any dangerous pathogens?”
“No,” Jake said.
Vlad jumped in. “Neither do I. We develop technology on harmless stuff. Cold rhinoviruses. E. coli. Nothing that is not in you already.”
Becraft looked unsatisfied. “Could the Crawlers be used for something dangerous?”
“Like what?”
“I don’t know. Could they be used to make a pathogen instead of test for one?”
“No,” Vlad said. “You would need more than just Crawlers. You would need an entire lab.”
The inspector rubbed his eyes. “So. Let me be clear. A few missing Crawlers by themselves would be completely harmless.”
Jake started to answer, but Vlad got there first. “Well. No. Not necessarily.”
Becraft stared at the Russian.
Jake knew what was coming. He and Vlad occasionally strayed into this kind of territory in their late-night drinking-and-tale-spinning sessions. Wars fought by insect robot proxies. A disgruntled kid crossing a rhinovirus with smallpox and killing off half the country.
Vlad said, “What if you already had pathogen? You could store it inside Crawler. Then you could carry Crawler around in package of Chiclets. Shake it out, it could find its way anywhere. Crawl into a ventilation duct. Slip under a door. The Crawler could even bite someone. Inject pathogen into wound. You have a pathogen you want to get out? A Crawler would make hell of a vector.”