Remember how it feels to slide down a water slide?
Well, what if the water was not merely below you but all around?
What if the water slide was a little bigger, a little curvier, and you weren’t sliding alone but with numerous other people?
Sounds a little messy, doesn’t it?
Yet somewhere along the way, that messiness is bound to transform into a certain pattern, but why?
Now, imagine you are a miniature particle — a cell, if you like — immersed in a liquid with a load of other cells floating around you.
From the point of view of that cell, you are inside a syringe about to be catapulted into a long, spiral, strange-looking, almost perpetual tunnel.
Join me on a bizarre, rollercoaster journey of a cell inside a channel…
…a journey that illustrates how a unique microchannel design has enabled us to diagnose whether cancer exists in a blood sample or not.
Yes, you read that right.
You are going on a wild microscopic odyssey as an actual cancer cell into the depths of a unique microchannel.
Why, you ask?
Well, this award-winning microchannel geometry has successfully shown the potential to help diagnose metastatic cancer at an earlier stage than that of traditional diagnostic methods…
…and I co-invented it.
So, I thought I’d tell you a bit about it through a thrilling story starring you as a cell.
I would tell you to buckle up, but since you are a cell in a liquid, the best pun I could come up with is just: go with the flow.
You are floating in an enclosed, still ocean. Everything around you is serene.
You look around, and you see various other cells…some smaller, some as big as you, but they’re all floating, just like you. Nothing special, just stillness.
It’s all quiet…
…maybe a little too quiet that you start to have a hunch that something is about to happen — something that’ll upend this whole tranquillity into mayhem.
If your hunches ever disappointed you before, this one isn’t going to.
As you’re thinking of that hunch, you begin to realise that everything around you begins to forcefully move in one direction, getting sucked into some sort of an opening…
…an opening almost resembling a black hole, where all the cells around you, all the still liquid you were floating in, everything is falling into it.
You look behind you, and all of a sudden, you see a massive wall pushing everything towards that hole…
…and there you accept your fate and think: “This is it. I’m going to fall, too.”
By the time you reach the hole, you are sucked into a tunnel, plunging your way into a pool where tranquillity has no meaning.
No time to contemplate, as more and more cells like you are pouring down the tunnel.
You try to look round, and you see the water around you flowing through a large rectangular canal of some sort, gushing into oblivion.
It all seems too bizarre.
If the cells had voices, they’d be crying for their lives. And who knows? Maybe you’d be, too.
But there you go, into the mystery waterway.
As the water takes you through the rectangular channel, you begin to see curves…after curves…after curves…
…an almost endless series of curvature going right to left and back to right again…the type of “waterslide” that’d nauseate you.
“What in the world is this?” you ask yourself.
But then, something almost mystical happens.
As you’re flowing, your eyes capture an intriguing phenomenon.
All the cells that look like you, or are in fact as big as you, begin to flow closely next to you.
You look behind you, in front of you, you’re all quite similar…almost forming a thick trail of identical cells right next to one of the sidewalls of the channel.
All the other cells that are smaller than you are flowing far away on the other side.
And then you begin to notice a pattern forming.
The further you go, the closer the similar cells are to you — and the thinner your trail becomes.
You begin to clearly see the water flow not turbulent anymore. You are back to tranquillity.
The only difference is that now you’re not floating in a still ocean anymore. Instead, you’re gliding through a channel together with everything around you.
You start to realise that the channel curves are following a sequence, too.
Whenever you pass through a big curve, the next one is always small.
Then comes another big curve, and surprise! There comes another small one.
This periodic sequence seems to continue endlessly.
You start to understand that you have not in any way been swimming of your own free will.
As you were flowing, forces were pushing you around, vortices swirling and carrying you sideways…all the way until you couldn’t move closer to or away from the sidewall.
Something kept you stable and close to the other lookalikes while it moved the others away.
And with everything becoming more fathomable, one more realisation emerges.
You start to feel like all those curves are in fact spiralling inwards; as if this whole curvy path is superimposed on some spiral trajectory…
Could this be the reason that all the cells that look like you are flowing ever closer to you, while the others disperse away?
Could all this be intentional to separate you from the others?
If this were intentional, who intended it?
Is there anything special about you?
As you’re going through all those realisations, one thing completely stumps you!
You are radiating! You have been radiating all this time.
A green light is coming out of you and it seems to be lighting your path.
But wait! It’s not just you.
All the other similar cells around you are radiating too! And it’s all green!
Out of curiosity, you look over to the other side…
Interestingly, all the other cells are radiating a fainter red light.
You look down, and a mightily bright white light is shining powerfully at you.
Could this be the reason you are radiating?
Clearly, something intentional is going on!
While all this is happening, you look ahead and see the path divide into two!
You see yourself falling towards one path as the trail of green light ahead is bending towards that side.
All the red cells seem to be on their way into the other path of the channel.
You cannot change anything. The forces have kept you on a focussed path together with all the other green-radiating cells.
All you can do is sit tight and go with the flow.
“Here we go. This is it,” you whisper, as you brace yourself for what’s coming.
As you follow your path, you end up in a wide circular pool, a pool that resembles that first one you fell into when you got drawn into that first hole.
But clearly, this one is different. This one only has green cells in it.
You’ve been segregated.
You begin to wonder, “Did the red cells end up in a similar pool with only other red cells? It’s only logical that they did. Otherwise, where would they go?”
As you’re wondering, another wormhole-like tube pulls almost everything out of your pool and lays you onto a flat, transparent panel.
Another powerful, white light shines at you from below.
You lie down there, motionless, powerless, lifeless.
The Meaning Behind the Journey
What an exhausting journey that was!
But an enlightening one, nonetheless.
You were actually right in all your questions.
Yes, it was intentional to separate cells by size because, in reality, cancer cells tend to have larger size variability than red blood cells, reaching a size difference of about three times.
Such a separation allows us to detect cancer cells with high precision.
This precision is driven by the unique geometry of the channel. All these curves are purposefully situated and designed in a way that would reinforce the focussing of same-size cells together while keeping different-size cells separate.
We call this design the Sunflower, and it is in fact a superposition of periodically large and small curves on a spiral trajectory.
By collecting samples from the two outlets at the end, we are simply able to see a size-based separation that can give us indications of the existence or nonexistence of cancer cells in the sample.
The radiating colours mentioned are actually fluorescent staining dyes put into the cells before the experiment in order to view them under the microscope — which has the powerful white light that helps us see the coloured cells.
In this story, you were special. You were a cancer cell. You were meant to be detected. All this was performed in order to find you and make a decision on whether you exist or not.
And that’s the story of how our Sunflower microchannel has helped detect metastatic cancer in blood samples, earning us two awards, three scientific publications, and a patent.
But this is not the end of the fight against cancer. Diagnosis is only step #1. We are still in this tough fight together, and we all need to do whatever we can to help each other overcome this stubborn disease.