Nail Tagging to Identify Persons
Original Publication Date: 2004-Feb-03
Included in the Prior Art Database: 2004-Feb-03
A method to identify people is presented here. This method is based on placing an adhesive chip identifier onto the nail of a person. This method can be used to identify patients in healthcare environments and to link patient to their body samples unequivocally.
Nail Tagging to Identify Persons
Personal identification is of growing importance for commercial transactions, security, military applications, and healthcare. The automated identification of individuals is desirable and can be done using biometric techniques or keys/passwords possessed by one individual. The identification of individuals in healthcare environments is particularly desirable to identify patients and provide them with the appropriate care, i.e. the right therapy or the necessary diagnostic test. In most cases, blood samples and other specimens are taken from patients without establishing unequivocal links between the patient, his specimens, and the data resulting from using the specimens for clinical tests. Unfortunate errors occur from misattributing samples to wrong patients.
Biometrics is a convenient, relatively safe, and cheap authentification technique but it uses a trait characteristic of a person, and therefore is difficult to deploy in some environments, is prone to errors, and is "information poor" unless the identified person can be linked to prerecorded data. It is proposed to employ tagging chips to identify people; these chips can have variable amount of information and can be carried by people on fingernails.
Fingernails represent a well defined and redundant medium for carrying tags. Nails are typically not exposed to wear unlike other parts of the body and tags on nails can be made nonpermanent. In principle, a pattern can be written in a nail directly using a laser [1, 2] or by injecting colored beads under the nail . The proposed approach is simpler and based on writing the desired information on a medium such as a sticker and placing the sticker on the nail. More specifically, the information can be coded by fluorescent molecules patterned on a thin layer, which is sandwiched between adhesives. The pattern can be invisible to bare eyes under ambient light but can fluoresce and be visible under UV light. Alternatively to fluorescent molecules, the information can be coded using beads, dyes, pigments, particles or molecules, polymers, colloids, etc. Beads can be highly fluorescent, chemically stable and mechanically resistant, and with sizes ranging from less than a micrometer to more than 10 micrometers.
Figure 1 shows an example of a tagging chip that was made by patterning fluorescent dyes on an adhesive layer. A UV curable resin (Norland) was molded against a PDMS master and photocured. The hardened resin was subsequently soaked in a saturated solution of coumarin in acetone during which coumarin dyes diffused into the resin. After drying the molded resist containing the dye, the structure was finally attached to an adhesive tape to form the tagging chip. The smallest features in the chip in Figure 1 are 10 micrometers wide. The chip is 20 micrometers thick and flexible. It can be...