From Super Glue to Dusting: Four Phenomenal Ways to Lift Fingerprints

By November 5, 2012ID

It’s the stuff of Marple and Poirot: the dark contours of a detective in the shadows, leaning over a table with a magnifying glass firmly in hand. At over one hundred-years-old, it’s certainly one of the the oldest disciplines within forensic science. Contrary to popular perception, fingerprinting as its own field has evolved tremendously since then. We’re a long way from prehistoric picture writing where people stuck their thumbs in clay or even those filed fingerprint sheets from the late 1890s.

This isn’t to say some of the more conventional methods have been completely abandoned. Fingerprints, the most commonly-used forensic evidence all over the world, can be recovered in multiple ways according to surface or substrate — some approaches are more traditional, and some are decidedly dependent on modern technology (as is the case with national fingerprint databases). In any case, wherever you’ve left them, there’s probably a way to find them (shouldn’t make you nervous, right?)

If you’re ready to embark on your own personal investigation, we’ve reviewed five innovative ways to lift fingerprints (and detailed when and where to use them, for maximal recovery).

 

Detective work, Sherlock, not a chore: dusting for prints.


Despite what impression you might get from TV crime shows, it’s not as simple as getting out your bristly brush and sweeping it across any old wine glass or paper-filled bureau. There’s a method to sampling and recovering fingerprints in a crime scene — where an investigator has the daunting task of lifting impressions from any surface potentially involved.

In all cases, remember this: fingers are coated with perspiration (or sweat, to be simple about it). All the oiliness of your stubby little digits create latent (or invisible) prints on everything you touch, leaving behind a little piece of you as you go about your everyday life. That’s the stuff that powders pick up.

Dusting involves some sort of implement — anything from a squirrel-hair or fibreglass brush, to a magnetic wand — and a powder, like aluminum or magnetic powder (the “oohs” and “aahs” we get when we’re demonstrating how the latter works during workshops is always something to anticipate). The movement you make with your wrist depends largely upon the surface, the tool and the powder you’re utilising for the task.

 

Cyano-what? Superglue fuming.


The story behind this one is kind of a gem. The idea of recovering fingerprints with superglue wasn’t a genius suggestion — it was more like a happy accident. It all started with a guy named Fuseo Matsumur (an epic name, if you ask us) who was a hair and fiber expert in Japan. One particular workday, he was tasked to glue hair samples from the crime scene for routine microscopic examination.

It wasn’t too long before he noticed his own powdery but detailed fingerprints becoming visible on the edges of the slides he was using. He became the first to determine that using fumes from the Superglue (or cyanoacrylate adhesive) constituted a reliable fingerprint recovery method. Unsurprisingly, using a cardboard box, a well-ventilated area and some superglue — it’s not all that difficult to repeat his findings.

 

Another kind of bullet fingerprint.


Ever in a situation where you need to develop fingerprints from a bullet casing or bomb fragment? We didn’t think so. If you ever do find yourself in this unlikely situation, we’ve got precisely the approach you’ll need to determine whodunnit — safely and accurately. Very recently (think 2008), scientists developed a method which relies on the subtle corrosion or breakdown of metal surfaces to determine what a given impression looked like.

Chloride ions in our sweat acts like a chemical agent against casings; and of course, these ions are present in our sweat — which is how we leave latent prints. If you can take a closer glimpse at the part the ions corrode, you can visualise the patterns. Access to 2500 volts means you can pass an electric field through the metal. Add some fine conducting powder to the mix, and it’ll stick to the corroded areas.

 

Lighting them up: prints that glow.


Electroluminescence not only looks spectacular under the right kind of microscope, it’s also the most recent method to recover fingerprints (the announcement was only made in August 2012). A given fingerprint is pressed onto an electrode which is either composed of indium tin oxide or a stainless steel sheet. Then, the electrode is immersed into a special chemical solution. When a voltage is applied to the electrode, the fingerprint lights up — giving off a wondrous and luminescent glow that shows the impression in exquisite detail without any damage.

It’s a harder technique to replicate, we’ll give you that — but still, pretty cool.

 

Your Turn: Know another sensational way to recover prints? Ever tried lifting your own fingerprints, at home, at school — or are you an expert in the laboratory? Let us know in the comments. We’d love to hear from you.

Comments

comments

8 Comments

  • Night Rider says:

    I’m a writer and don’t have a lab–only my computer and Google. Which is how I found you. The article is well-written extremely interesting, but what I’m trying to find out is what kind of surfaces any of these methods work on. Can you lift prints from clothing, for example? How about from another person’s skin? Thanks for the info!

    • The Forensic Outreach Team says:

      Hi there — the answer to both of your questions is yes, but with a caveat. The techniques to “lift” from various surfaces vary and with greater or lesser success. Casting materials, in combination with more traditional methods like magnetic powder that are first used to dust the area, are often utilised to preserve fingerprint evidence from such surfaces. Maybe we’ll write an article focusing on this in the near future.

  • Frances van Velzen says:

    Hi
    I’m a fine art student. I wish to discover a method for lifting the impression left by a bird which flew into a window. Ideally I would like to capture this impression eventually onto a sheet of paper. Any help gratefully received. Thank you. Kind regards Frances.

    • Hi Frances – you don’t say if the impression is in the dust or biologic. Let’s see what some of our readers come up with.

      Let us know how the impression comes out.

      • Leigh-Ann says:

        I am trying to do the same thing as Francis. The impression I would like to lift would mainly be an oily residue- so biological- where a bird crashed into my window.

  • Lillian says:

    Hi, I’m a 6th grader who wants to be in either the CSI, CIA or FBI when I grow up. I am doing a project in school where we have to determine the murderer of a “crime scene.” From reading your article I know that fingerprinting is the most commonly used, and reliable type of evidence out there. I dont have very many fancy tools like what you mentioned and I need an easy way to pick up fingerprints at school. I have made a powder out of starch and soot from the chimney (which is hard to collect if I might add!) To dust for fingerprints. However, I dont know how reliable this is. What do you recommend as an easy way for me to collect fingerprints without getting too technical?

    • Smart girl. You are on the right track. Generally, any fine powder that will be attracted to the oils left on a surface after a finger has touched them will do. Fingerprint powder is generally a very fine, dry powder that is graphite – based for black powder – used to outline prints on light surfaces – or talcum-based powder to discover prints left on dark surfaces. Graphite is the same as pencil lead, so if you have a pencil sharpener – and can sift the black powder from the wood shavings, you will have the right stuff.

      Baby powder works, so does corn starch or even cocoa powder. It is important that it is fine and dry.

      You also need a soft brush with very fine, soft bristles. Like a small paint brush. And some scotch tale. Clear. If you are going to use white powder, get some black construction paper. For dark or black powder, use white paper.

      Sprinkle a small amount of the powder on the print. Just a pinch. You don’t want your mother yelling about powder all over everything in the house. Once the print is covered, blow gently to remove most of the excess, then very softly, very carefully, just skimming the surface, lower the brush onto the print and, with a circular dabbing motion, brush away the dust that is between the ridges. Don’t swipe – that could smear the print. Be very careful, and practice on some of your own before you go for the one that is most interesting to you.

      Once you have the print outlined – and you can see the ridges and whorls – place a piece of clear tape down over it, leaving a corner unstuck so you can lift the tape off again. Press down softly on the print, lift the tape straight up, and you should have the print.

      Place teh tape on a piece of paper – dark for white powdered print – white for dark powdered print.

      Congratulations. You have indeed captured the print. Now, ask each member of your family to give you a set of their prints. Use a rubber stamp pad and mark which finger each print is from. Then compare. Was it your brother, your Mom or your Dad who was the last person who opened your dresser drawer?

  • Victoria Thompkins says:

    Hi, I’m doing a science fair project on how different methods of fingerprinting can give different results. Do you have any creative or suggested methods for fingerprinting, since I’m a student I can’t get anything too fancy.

Leave a Reply