Antibacterial Blu-Ray?

[Joshewon]

At wal-mart they have a machine that you bottle water out of. I remember it has a reddish type UV light that comes on as the water comes out to sterilize the water.

I have also heard something about IR light Structuring water. Making hexagonal structures out of the chains.

I will have to check that again.

 

[Cyparagon]

I've got news for you: UV isn't reddish.

 

[Spyderz20x6]

I've got news for you: UV isn't reddish.

;D ;D ;D

 

[Joshewon]

That is what i thought i remembered. I am not sure of UV Frequency but maybe it was like violet?? Not sure. Maybe someone can clear this up or i will see when i go back to walmart.

 

[suiraM]

I have used my 250mw green to heal cuts and acne(on my Daughter). I dont know if it is the heat that either kills the bacteria or just stimulates the immune system.

Do NOT repeat this experiment. Ever. And certainly not with Igor's blu-rays. Quick breakdown follows:

Red lasers:

- Aggravates certain skin diseases, including some forms of psoriasis where a mere 5mW will cause the patient to develop oozing blisters that appear permanent.
- Collapses blood vessels at certain power levels; I have successfully treated varicose veins with a red laser.
- Alleviates or cures certain kinds of inflammatory pain in the same way as an NSAID.
- Messes up the thyroid gland if applied directly with enough strength to reach it.
- Accelerates healing of superficial cuts, but causes extensive scarring.
- Accelerates growth of Pseudomonas bacteria; very hard to treat.
- Supposedly stimulates immune system (can be good or bad).
- Theoretical potential for cautery at high power levels.

Green lasers:

- Accelerates growth of Pseudomonas bacteria; very hard to treat.
- Causes instant vasodilation in some types of blood vessels.
- Too high powers will cauterize the same blood vessels.
- Intermediate powers damage vasoregulation.

405nm lasers:

- Increases oxidative stress on cells, raising the risk of melanoma.
- Kills a few types of bacteria, notably Pseudomonas.
- Effective for cautery at surprisingly low power.
- Some potential surgical applications.

Apart from this, if you deliver more than 15mW to the basal layer of your skin, that can cause local damage. More than 25mW to the basal layer of the skin will cause blood vessels to die locally, which is used for precise and permanent hair removal. As in all cases, the amount that penetrates the skin, and how focused it is, will determine the extent of any damage or therapeutic effect. For instance, there are wavelengths in the 1-1.5µm spectrum where the water in your cells will be transparent. Melanin absorbs pretty damn well at 405nm, but peak absorption is somewhat lower. Hemoglobin absorbs optimally in the 620-660nm range. If you focus one of Igor's burners on a wound, you will most likely cauterize it, causing extensive scarring and possibly basal cell carcinoma, depending on the length of exposure and your phenotype. Any latent melanomas in the area (pre-stage where keratin modification has been activated, but before proliferation has occured) are likely to be triggered.

Mind you, I didn't bring out my references, so this is all just from memory.

Of course, the 405nm lasers' diffuse reflections off skin will be harmful to your eyes in the long run, particularly if you have blue eyes or have genetic heritage from nordic areas.

The point, in plain English: do not attempt to use a laser to treat any medical condition without the supervision of a doctor that knows how to use the different wavelengths and power levels to treat specific conditions. Do not allow one to rest on your skin for a long period of time, particularly ones with high power and/or IR and/or UV content (including 405nm, which is close enough to do real damage). Just because you can't see the damage occuring before your eyes doesn't mean you won't have after-effects showing up years later. Nor does the absence of long term effects mean anything other than having made a lucky draw in the lottery.

To reiterate, don't burn your daughter's wounds with one of Igor's lasers.

Unless a doctor tells you to do so, and how, of course.

 

[suiraM]

Addendum: sterilization of surfaces is performed with 251nm high-intensity light, which causes T-T crosslinks in the DNA of all living organisms, including humans. Staying in the area for a short amount of time will cause sunburn. A bit longer causes third degree burns. After that, you're going to give the radiation burn lab at the hospital a run for their money.

For the guy asking about burning, as someone said, it depends on wavelength. Metals are most effectively burned at low wavelengths. The absorption of copper and aluminium is close to 50% at the wavelengths emitted by a Blu-Ray laser.

For those that haven't looked at the datasheets, the Blu-Ray lasers peak at 405nm +/- 10nm, but they have significant secondary modes at shorter wavelengths.

 

[Switch]

Wow, where do you work? Never thought lasers in the middle of the spectrum can be that damaging.Still how can a mere 25mW of green be used for hair removal? I thought they used YAG or something. :-/

The absorption of copper and aluminium is close to 50% at the wavelengths emitted by a Blu-Ray laser.

You don't say.... :-?

 

[suiraM]

Long-term medical leave right now. Prefer to be an independent consultant for the variety. Fields I've worked in range from psychiatry to IT to security to project management to self defense instructor. I learn quickly, but I'm just starting out as far as laser technology goes. The medical bits were a chance discovery that intrigued me a bit at the time.

As for middle of the spectrum: hardly. Middle of the visual spectrum, perhaps.

25mW is when that much energy arrives at the root, in which case most of it is absorbed by the melanin pigment. A tenth of a second is enough to kill the root. But, yes, they tend to use YAG. I was referencing a patent that dealt with the transmission window of the skin vs the absorption ranges of melanin, and the amount of optical energy that needed make it down to the root in order to kill it permanently. Pigments in the higher layers of the skin make it hard to actually get 25mW of green down there, and you must remember that we're talking about a precise delivery, i.e. the hair and root. The average greenie will not be focused right to hit the correct area, and may well lack the power to penetrate that deeply. And if it does, it will most likely cause a lot of collateral.

Still, plenty of reasons to avoid experimenting with lasers on yourself without doing the research.



Incidentally, if anyone knows a "cheap" non-solar way to get enough short wavelength energy to ablate copper traces on a PCB, I would be very interested. Slow is fine. The CNC stage will hopefully be completed soon, and I'd rather not have to focus a ton of PHR's at the same spot just to get some trace cutting action going, plus the neighbours would be real happy if I set up a solar tracking collector that can deliver that much in a fiber bundle... not.

 

[Switch]

As for middle of the spectrum: hardly. Middle of the visual spectrum, perhaps.

Yea , that's what I usually mean by "the spectrum".

Anyway, 25mW is actually a lot of green, not likely to be found in nature or any other usual situations.

As fof the copper ablation, I think a ton of PHR's is gonna be your best bet I mean , since that wire marker cost $500.000...yeah..

 

[Spyderz20x6]

As for middle of the spectrum: hardly. Middle of the visual spectrum, perhaps.

Yea , that's what I usually mean by "the spectrum".

Anyway, 25mW is actually a lot of green, not likely to be found in nature or any other usual situations.

As fof the copper ablation, I think a ton of PHR's is gonna be your best bet I mean , since that wire marker cost $500.000...yeah..

I don't think you would find green laser light in a natural situatuon anyhow...

 

[rocketparrotlet]

I know that the SteriPen water filtration system works by UV light, and 405nm is very close. I think that a Blu-Ray laser would work well for the same purpose, although I may have to do some tests to determine if it is safe. Does anyone know how I could test this?

-Mark

 

[tomcat]

405 is way too high to really harm microbes, the only damage done would be heat damage not irradiation with UV (causing the sell to get fatal dna corruption and suicide

for killing bacteria i would say under 380nm about <200nm would give best results

 

[rocketparrotlet]

405 is way too high to really harm microbes, the only damage done would be heat damage not irradiation with UV (causing the sell to get fatal dna corruption and suicide

for killing bacteria i would say under 380nm about <200nm would give best results

Okay, I think I'll just stick with my SteriPen then.

-Mark

 

[suiraM]

What's wrong with peroxide, iodine, mercury and various semi-toxic metals?

A healthy respect for 251nm light is advisable. There are good reasons why the hospital isolab is located close to the burn unit: it's not so much a matter of killing germs with that wavelength, as it is a matter of killing DNA-based life with it (i.e. all organic life, including humans, given enough exposure, which is less than you probably think). And, if memory serves, krypton fluoride lasers are the only ones that are close enough to that wavelength. Those have enough power to make the wavelength question rather academic, however.

Anything other than 251nm is going to be specific to the bacterial strain in question.

"I say we take off, nuke the site from orbit... it's the only way to be sure."

 

[Switch]

What about RNA based life? ;D

 

[suiraM]

Methinks those would leave nothing but stains...