Abstract:
Provided are a barcode nano-wire for decoding a hard magnetic segment by using highly sensitive magnetic sensors and a bio-sensing system using the barcode nano-wire. Integration of hard magnetic and non-magnetic segments produces the barcode nanowire and magnetic segments are detected using highly sensitive magnetoresistance sensors. The non-magnetic segment uses a non-magnetic material and a specific biomolecule for bioanalysis is immobilized at a specific portion of the barcode nano-wire. The hard magnetic material has an advantage of higher coercivity and high remanence magnetization, which is considered as an important parameter in selecting the material. The hard magnetic segments produce distinguishable strong stray fields for individually detecting segments using conventional magnetic sensors for multiplexed bioanalysis.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 to Korean Patent Application No. 10-2010-0026632, filed on Mar. 25, 2010, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The following disclosure relates to a digital barcode nano-wire having a multi-segmented hard magnetic/non-magnetic segment structure and a system for bio-sensing using the same, and in particular, to a miniaturized and multiplexed bio analysis device for disease diagnosis and genomics. 
     BACKGROUND 
     Recently, miniaturized and multiplexed analysis devices for disease diagnosis as well as genomics generate intense research interest in nano/micro technology-based bio applications. One of the major methods for multiplexing is based on distinguishable particles-based suspension in which each type of probe biomolecules such as protein and deoxyribonucleic acid (DNA) is immobilized. 
     Many encoding and decoding methods have been developed to attach a unique probe biomolecule to a unique particle in suspension and to detect the target molecule. For example, a diagnostic device using color-coded bead suspension, which contains polystyrene microbeads embedded in red and orange fluorescent dyes at different ratios for yielding distinctive colors, has been already commercialized by the incorporation of flow cytometry technology. The color code is decoded with reflected color image excited by a laser. 
     Alternatively, a recently developed suspension platform for biosensing uses multi-segmented nanowires, which are fabricated by alternating electrodeposition within a porous template with different metals such as gold (Au), silver (Ag) and copper (Cu) for the respective segments, as “barcodes” for the multiplexing. The barcode is decoded with the difference in optical reflectance of gold and silver segments. 
     Both of the two representative biosensing technologies, which use suspensions of color-coded microbeads and barcoded nanowires respectively, require laser-based instrumentation, a charge-coupled device (CCD) camera and image processing software for decoding and thus suffer from disadvantages in miniaturization and cost-effectiveness. In addition, the optical detection of nanowires is extremely difficult because nanowire diameters are on the limit of optical detection by a normal microscope. Moreover, it is not so easy to distinguish the barcode segments in these nanowires due to the interference crisis. 
     On the other hand, magnetic planar tags using an optical-magnetic characteristic in a soft magnetic material have disadvantages because the low remanence magnetization and the information coded on the planar tags may be erased due to small unwanted external magnetic fields. Decoding the information on the planar tags requires optical detection which is expensive to procure. 
     In order to overcome these disadvantages and to develop sufficiently miniaturized, multiplexed and cost-effective biosensing systems, a novel encoding and decoding method is required. 
     SUMMARY 
     An embodiment of the present invention is directed to providing a new type of digital barcode nano-wire for decoding a hard magnetic segment using magnetic sensors. 
     Another embodiment of the present invention is directed to providing a system for sensing biomolecules by aligning, sorting and decoding a magnetic-based barcode by using magnetic beads or magnetic nanoparticles. 
     In order to realize the above-mentioned embodiments, provided are a digital barcode nano-wire and a sensing system. 
     In one general aspect, a digital barcode nano-wire, includes: a hard magnetic segment showing digital information; a non-magnetic segment showing digital information different from the hard magnetic segment; and a spacer that is disposed between the hard magnetic segment and the non-magnetic segment, between the hard magnetic segment and the hard magnetic segment, or between the non-magnetic segment and the non-magnetic segment, and that does not show digital information. 
     Detecting biomolecules for combining with probe biomolecules formed on a surface of a magnetic bead are formed on the non-magnetic segment surface. 
     In another general aspect, a digital barcode nano-wire, includes: a hard magnetic segment showing digital information; a non-magnetic segment showing digital information different from the hard magnetic segment; and a spacer that is disposed between the hard magnetic segment and the non-magnetic segment, between the hard magnetic segment and the hard magnetic segment, or between the non-magnetic segment and the non-magnetic segment, and that does not show digital information; and a coating film coating the hard magnetic segment, the spacer and the non-magnetic segment surface with gold (Au) or silver (Ag). 
     The digital barcode nano-wire has a core-shell structure. 
     Detecting biomolecules for combining with probe biomolecules formed on a surface of magnetic nano particles are formed on a surface of the coating film. 
     The hard magnetic segment represents “1” and the non-magnetic segment represents “0”. 
     The hard magnetic segment as a material with large remanence may be formed of any one of hard magnetic materials including CoNiP, CoPtP and CoMnP. 
     The hard magnetic segment may be formed of gold (Au), silver (Ag) and copper (Cu). 
     Also, the non-magnetic segment may be formed of gold (Au) or silver (Ag) to immobilize a specific biomolecule for bioanalysis on an end or the entire surface. 
     In still another general aspect, a bio-sensing system in a fluidic state, includes: a nano-wire inlet introducing a digital barcode nano-wire; a sample inlet introducing a sample; a hybridizing unit forming a hybridized digital barcode nano-wire with the attached sample and a non-hybridized digital barcode nano-wire without the attached sample by hybridizing the digital barcode nano-wire and the sample; an aligning and sorting unit transmitting the hybridized digital barcode nano-wire to a hybridized channel and transmitting the non-hybridized digital barcode nano-wire to a non-hybridized channel by separating the hybridized digital barcode nano-wire and the non-hybridized digital barcode nano-wire; an encoding unit for encoding the separated hybridized digital barcode nano-wire; and a decoding unit decoding the encoded hybridized digital barcode nano-wire. 
     The encoding unit includes a pulsed magnetic field generator applying pulsed magnetic fields to the hybridized digital barcode nano-wire. 
     The decoding unit includes a magnetic sensor reading digital information by sensing the encoded hybridized digital barcode nano-wire. 
     The magnetic sensor may be any one of a semiconductor hall sensor and a magnetoresistance sensor of Giant Magneto Resistance (GMR), Planar Hall Resistance (PHR), and Tunneling Magneto Resistance (TMR). 
     The magnetic sensor senses the encoded hybridized digital barcode nano-wire at a distance of 10 μm or less from a bottom of the hybridized channel. 
     The sample is a superparamagnetic bead or a magnetic nano particle and the magnetic nano particle is a constituent element of the magnetic bead and acts as a guiding substance. 
     The sample is attached to the digital barcode nano-wire through ligand-receptor interaction. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows hard magnetic barcode nanowires with three unique digital barcodes according to an exemplary embodiment. 
         FIG. 2  shows nanowires attached to the superparamagnetic magnetic beads functionalized through specific ligand-receptor interaction according to an exemplary embodiment. 
         FIG. 3  shows a core-shell structure of the barcode nanowires according to an exemplary embodiment. 
         FIG. 4  is a system showing a method for aligning and sorting along with encoding and decoding concept of barcode nanowires inside a fluidic channel according to an exemplary embodiment. 
         FIG. 5  is a graph showing a sensor signal variation with respect to different codes of the barcode nanowires according to an exemplary embodiment. 
         FIG. 6  is a graph showing a sensor signal variation depending on both a distance of the sensor from the nanowires and code information according to an exemplary embodiment.OF MAIN ELEMEMTS 
     
    
    
     DETAILED DESCRIPTION OF MAIN ELEMENTS 
     
         
           100 : barcode nano-wire 
           100 - 1 : hybridized barcode nano-wire 
           100 - 2 ; barcode nano-wire 
           101 : detecting biomolecules 
           110 : hard magnetic segment 
           120 : spacer 
           130 : non-magnetic segment 
           200 : spherical magnetic bead 
           200 - 1 : quadrangle magnetic bead 
           200 - 2 : triangle magnetic bead 
           210 : probe biomolecules 
           300 : coating film 
           310 : magnetic nano particles 
           311 : detecting biomolecules 
           400 : nano-wire inlet 
           410 : sample inlet 
           420 : hybridizing unit 
           430 : aligning and sorting unit 
           431 : upper portion 
           432 : lower portion 
           440 : encoding unit 
           441 : magnetic south pole 
           442 : magnetic north pole 
           450 : decoding unit 
           451 : magnetic sensors 
           460 : hybridized channel 
           470 : non-hybridized channel 
           490 : test-bed 
       
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     The advantages, features and aspects of the present invention will become apparent from the following description of the embodiments with reference to the accompanying drawings, which is set forth hereinafter. The present invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. 
     A digital hard magnetic barcode having following characteristics according to an embodiment of the present invention will be described in easy-to-understand manner.
     1. Hard magnetic segments are favored due to high remanence, high coercivity and stronger stray fields; thus these properties are useful for storing encoded information in barcode nanowires using external magnetic fields as well as decoding the magnetic barcode segments using highly sensitive magnetoresistance sensors (magnetic sensor).   2. These barcode nanowires may be used as a platform for multiplexed biosensing when a unique probe biomolecule is attached to a unique digital barcode of the nanowire. Therefore, increasing the number of segments by n increases the multiplexing ability of the barcode nanowires by 2 n  codes.   3. The development of a multiplexed diagnostic system using barcode nanowires decoding technique is necessary. Accordingly, it is possible to read the hard magnetic barcode segments by the highly sensitive magnetoresistance sensors (magnetic sensor) under incorporation with flow cytometry or magnetic fluidics technologies.   4. This magnetic barcode is encoded by a magnetic field and decoded by a magnetic sensor. Accordingly, the magnetic barcode system is more compact and cost-effective than general biosensing systems used for optical encoding and decoding methods.   

     The digital hard magnetic barcode according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings hereinafter. 
       FIG. 1  shows hard magnetic barcode nanowires with three unique digital barcodes according to an exemplary embodiment. That is,  FIGS. 1(   a ),  1 ( b ) and  1 ( c ) show the hard magnetic barcode nanowires  100  with digital barcodes  101 ,  111  and  100 . The hard magnetic barcode nanowires  100  are the combination of a hard magnetic segment and a non-magnetic segment. 
     The hard magnetic barcode nanowires  100  adopt a multi-segmented nano-wire suspension method and the multi-segmented nano-wire suspension is fabricated by alternating electrodeposition with non-magnetic segment materials and hard magnetic materials. 
     These barcodes are synthesized with different units and represent a non-magnetic segment as “0”, a hard magnetic segment as “1”, a non-magnetic segment as “1”, and a hard magnetic segment as “0”. 
     As shown in  FIG. 1 , the hard magnetic barcode nanowires  100  include three segments and a spacer  120  is disposed between the segments. 
     For example, ‘0’ represents a non-magnetic segment  130  and ‘1’ represents a remanence material segment  110 . Also, the spacer  120  as a conductor represents a portion, which does not include information. The remanence materials include CoNiP, CoPtP, CoMnP and SmCoP. The non-magnetic segments include gold (Au), silver (Ag) and copper (Cu). The spacer includes non-magnetic gold (Au), silver (Ag), and copper (Cu). 
     In  FIG. 1(   a ), a barcode is marked as ‘ 101 ’, which includes the remanence material segment  110 , the spacer  120 , the non-magnetic segment  130 , the spacer  120 , and the remanence material segment  110  in order from the left side. In  FIG. 1(   b ), a barcode is marked as ‘ 111 ’. In  FIG. 1  ( c ), a barcode is marked as ‘ 100 ’. 
     That is, the barcode ‘ 111 ’ includes only the remanence material segment  110 . The spacer  120  is included between the remanence material segment  110  and the remanence material segment  110 . In  FIG. 1(   c ), the barcode ‘ 100 ’ includes the remanence material segment  110 , the spacer  120 , the non-magnetic segment  130 , the spacer  120 , and the non-magnetic segment  130  in order from the left side. 
     Biomolecules such as protein and deoxyribonucleic acid (DNA) may be easily separated and detected by using the hard magnetic barcode nanowires  100 . The hard magnetic segment  110  may be used for decoding by highly sensitive magnetic sensors and the spacer  120  is used for immobilizing a specific biomolecule. 
     In the exemplary embodiment of the present invention, the hard magnetic barcode nanowires  100  are illustrated as a circular shape but are not limited thereto. Shapes such as quadrangle, hexagon and octagon may be used. 
     A method for attaching a magnetic bead to the hard magnetic barcode nanowires  100  shown in  FIG. 1  will be described hereinafter and is shown in  FIG. 2 .  FIG. 2  shows the nanowires attached to superparamagnetic magnetic beads functionalized through specific ligand-receptor interaction according to an exemplary embodiment. 
     With reference to  FIG. 2 , the spherical magnetic bead  200  is attached to one end of the hard magnetic barcode nanowires  100 . Probe biomolecules  210  are randomly attached on the surface of the spherical magnetic bead  200  and detecting biomolecules  101  are also randomly attached on the surface of the hard magnetic barcode nanowires  100 . 
     The spherical magnetic bead  200  is formed by coating magnetic nano particles, e.g., metals and oxides, with substances such as polystyrene having excellent insulating properties and transparency. Each of the detecting biomolecules  101  and the probe biomolecules  210  is formed on the surface by immersing the hard magnetic barcode nanowires  100  and the spherical magnetic bead  200  in a specific solution of different biomolecules. 
     Therefore, the detecting biomolecules  101  formed on the surface of the non-magnetic barcode nanowires  100  and the probe biomolecules  210  formed on the surface of the spherical magnetic bead  200  are attached through ligand-receptor interaction. It is shown in an expanded figure. That is, the probe biomolecules  210  and the detecting biomolecules  101  are connected only when they have the same property that interaction is possible. 
     The spherical magnetic bead  200  may be a superparamagnetic bead. The superparamagnetic bead  200  acts as a guiding object of the functionalized barcode nanowires  100  for aligning and sorting in a microfluidic channel. The hard magnetic barcode nanowires  100  do not have remanence until magnetic fields are applied. 
       FIG. 3  shows a core-shell structure of the barcode nanowires according to an exemplary embodiment. With reference to  FIG. 3 , the coating film  300  with gold (Au) or copper (Cu) coating is formed on the surface of the hard magnetic barcode nanowires  100 . 
     Therefore, the hard magnetic barcode nanowires  100  have a shape of a core-shell type. Magnetic nano particles  310  are attached on the surface of the coating film  300  through the probe biomolecules  311  and detecting biomolecules  102 . Since the description on the probe biomolecules  311  and the detecting biomolecules  102  is similar to that in  FIG. 2 , it will not be provided herein. 
     The magnetic nano particles  310  are particles included inside the spherical magnetic bead  200  shown in  FIG. 2  and metal materials or oxides are used. The magnetic nano particles  310  is attached on the surface of the coating film  300  through hybridization of a specific biomolecule. Aligning and sorting of the hard magnetic barcode nanowires  100  of the core-shell type are performed in the microfluidic channel by applying external magnetic fields on a microfluidic wall. 
     That is, only the hybridized barcode nanowires  100  may be aligned and sorted as a specified channel by applying the magnetic fields inside the fluidic channel. The non-hybridized barcode nanowires  100  may be aligned and sorted as other channels different from the specified channel. 
     With reference to  FIGS. 1 to 3 , a procedure of encoding, decoding aligning and sorting the hard magnetic barcode nanowires  100  inside the fluidic channel will be described. It will be conceptually shown in  FIG. 4 . 
       FIG. 4  is a system showing a method for aligning and sorting along with encoding and decoding concept of barcode nanowires inside the fluidic channel according to an exemplary embodiment. With reference to  FIG. 4 , a test-bed  490  for encoding, decoding and aligning and sorting the hard magnetic barcode nanowires  100  illustrated in  FIGS. 1 to 3  is disposed. 
     A sample inlet  410  for introducing the magnetic bead  200  as a bio analyte, a nano-wire inlet  400  for introducing the hard magnetic barcode nanowires  100 , a hybridizing unit  420  for hybridizing the magnetic bead  200  and the hard magnetic barcode nanowires  100 , an aligning and sorting unit  432  for separating a hybridized barcode nano-wire from a non-hybridized barcode nano-wire, an encoding unit  440  for performing encoding by applying magnetic fields to the hybridized barcode nanowires  100 - 1 , and a decoding unit  450  for decoding the encoded hybridized barcode nanowires  100 - 1  are included on the test-bed  490 . Herein, the hybridized state means a state that the magnetic bead  200  is attached to the barcode nanowires  100  and the non-hybridized state means a state that the magnetic bead  200  is not attached to the barcode nanowires  100 . 
     A procedure of encoding, decoding, aligning and sorting performed on the test-bed  490  will be described as follows. 
     Each of magnetic beads  200 ,  200 - 1  and  200 - 2  and the hard magnetic barcode nanowires  100  is introduced through the sample inlet  410  and the nano-wire inlet  400 . The magnetic beads have different shapes according to the type of biomolecules.  FIG. 4  shows the spherical magnetic bead  200 , the quadrangle magnetic bead  200 - 1 , and the triangle magnetic bead  200 - 2 . The shape of the magnetic beads is not limited and shapes such as a hexagon shape are also possible. Also, other colors will be possible. 
     The introduced magnetic beads  200 ,  200 - 1  and  200 - 2  and the hard magnetic barcode nanowires  100  are hybridized in the hybridizing unit  420 . That is, as shown in  FIG. 2  or  3 , the magnetic beads  200 ,  200 - 1  and  200 - 2  are attached on the surface of the non-magnetic barcode segments  100 . The surfaces of the probe biomolecules  210  (see  FIG. 2 ) of the magnetic beads  200 ,  200 - 1  and  200 - 2  and detecting biomolecules  101  (see  FIG. 2 ) on the non-magnetic barcode segments  100  are combined by ligand-receptor interaction. At this time, there is no remanence magnetization of the hard magnetic barcode nanowires  100 . 
     The barcode nanowires  100 , to which the magnetic beads  200 ,  200 - 1  and  200 - 2  are attached inside the hybridizing unit  420 , become the hybridized barcode nanowires  100 - 1 . The barcode nanowires  100 , to which the magnetic beads  200 ,  200 - 1  and  200 - 2  are not attached, become the non-hybridized barcode nanowires  100 - 2 . 
     In order to separate the hybridized barcode nanowires  100 - 1  and the non-hybridized barcode nanowires  100 - 2 , the aligning and sorting procedure by the aligning and sorting unit  430  is followed. That is, when the hybridized barcode nanowires  100 - 1  and the non-hybridized barcode nanowires  100 - 2  enter inside the aligning and sorting unit  430 , the hybridized barcode nanowires  100 - 1  is located in an upper portion  431  inside the aligning and sorting unit  430  and the non-hybridized barcode nanowires  100 - 2  is located in a lower portion  432  inside the aligning and sorting unit  430 . 
     The barcode nanowires  100 - 1  and  100 - 2  separated in the aligning and sorting unit  430  progress along a hybridized channel  460  and a non-hybridized channel  470 . That is, the hybridized barcode nanowires  100 - 1  progress toward the hybridized channel  460  and the non-hybridized barcode nanowires  100 - 2  progress toward the non-hybridized channel  470 . That is, aligning and sorting of the barcode nanowires  100 - 1  and  100 - 2  are performed in the test-bed  490  according to two different methods. 
     In a first case, the hybridized barcode nanowires  100 - 1 , to which the magnetic beads  200 ,  200 - 1  and  200 - 2  are attached, are aligned and sorted by using lithographically patterned magnetic pathways within the test-bed  490 . That is, when the pathways inside the test-bed  490  are affected by external oscillating magnetic fields, the hybridized barcode nanowires  100 - 1  are aligned and sorted toward the upper portion  431  by the magnetic beads  200 ,  200 - 1  and  200 - 2  as a barcode guiding object through the magnetic pathways. When the microfluidic channels  460  and  470  are under oscillating magnetic fields, the magnetic beads  200 ,  200 - 1  and  200 - 2  attached to the hybridized barcode nanowires  100 - 1  acts as a guiding object of the functionalized barcode nanowires  100 - 1 . That is, the hybridized barcode nanowires  100 - 1  are aligned and sorted toward the hybridized channel  460 . 
     In a second case, the hard magnetic barcode nanowires  100  having the non-magnetic segment  130  of  FIG. 1  are aligned and sorted in the lower portion  432  of the aligning and sorting unit  430  by application of a small magnetic field gradient. That is, the non-hybridized barcode nanowires  100 - 2  are aligned and sorted toward the non-hybridized channel  470 . 
     The hybridized barcode nanowires  100 - 1  progressed toward the hybridized channel  460  are encoded in the encoding unit  440 . In other words, encoding of the non-magnetic segment  130  and the hard magnetic segment  110  of  FIG. 1  included in the hybridized barcode nanowires  100 - 1  is performed by using pulsed magnetic fields generated by magnetisms  441  and  442 , i.e., a magnetic north pole  441  and a magnetic south pole  442  included in up and down parts. Accordingly, the hybridized barcode nanowires  100 - 1  create remanence. 
     When the hybridized barcode nanowires  100 - 1 , to which the magnetic beads  200 ,  200 - 1  and  200 - 2  are attached, enter the decoding unit  450 , a decoding procedure is performed. That is, the segments  110  and  130  included in the hybridized barcode nanowires  100 - 1  are decoded. 
     The decoding is performed through highly sensitive magnetic sensors  451 . Semiconductor hall sensors and magnetoresistance sensors such as Giant Magneto Resistance (GMR), Planar Hall Resistance (PHR) and Tunneling Magneto Resistance (TMR) may be used as these magnetic sensors. 
     That is, the hybridized barcode nanowires  100 - 1  are encoded into high magnetic fields by the magnetism  441  and  442  of the encoding unit  440  and decoded by the highly sensitive magnetic sensors  451 . Therefore, the encoded information is read as digital information, i.e., the barcodes  101 ,  111  and  100 . Although it is not shown in the drawings, singularities of the biomolecule as a sample may be analyzed by connecting a computer (not shown) to the magnetic sensors  451 . The non-hybridized barcode nanowires  100 - 2  is separated by applying micro magnetic fields to the non-hybridized channel  470 . 
     Based on the above-mentioned barcode nano-wire, it is possible to align and sort the hybridized nano-wire with a proper bioagent and then recognize the singularity of the bioagent. 
       FIG. 5  is a graph showing a sensor signal variation with respect to different codes of the barcode nanowires according to an exemplary embodiment.  FIG. 5  shows a calculated magnetic field B x  in a wire direction for the different codes of the barcode nanowires such as digital information  100 ,  101  and  111 . That is, lines  500 ,  510  and  520  respectively represent the digital information  100 ,  101  and  111 . 
     It is considered that the calculated magnetic field B x  keeps a constant distance of 3 μm from the nanowires of three different barcodes  100 ,  101  and  111 , i.e., a distance between the surface of the magnetic sensor  451  in  FIG. 4  and the hard magnetic barcode nanowires  100 . Accordingly, it is possible to observe the magnetic field distribution of the individual barcode hard magnetic segment  110  separated by the non-magnetic segment  130  of  FIG. 1 . 
       FIG. 6  is a graph showing a sensor signal variation depending on both a distance of the sensor from the nanowires and code information according to an exemplary embodiment.  FIG. 6  shows the calculated magnetic fields B x  in the wire direction depending on both flying heights of the barcode nano-wires and barcodes  100 ,  101  and  111 . The flying height means the height of the hard magnetic barcode nanowires  100  from the floor of the microfluidic channels  460  and  470 . 
     In  FIG. 6 , when the flying height is 1 μm, a calculated value B x  for CoNiP is 0.5 mT. Based on the B x  magnetic fields calculation, the detectable range is several μm with respect to the CoNiP barcode nanowires using the magnetic sensors  451 . Preferably, the detectable range is from 0.5 μm to 10 μm but is not limited thereto. 
     In case of Planar Hall Resistance (PHR) sensor as one of the magnetic sensors, magnetic sensitivity, i.e., output voltage change according to the variation of the magnetic field, is 60 μV/mT and detection limit is 0.001 mT in general. 
     According to the present invention, since encoding and decoding are performed by using the barcode nano-wire formed of the multiplexed segments, it is possible to build an effective bio-sensing system. 
     In addition, the present invention aligns and sorts the barcode nano-wire by using the magnetic bead or magnetic nanoparticles in the barcode nano-wire. Accordingly, the magnetic barcode system is more compact and cost-effective than the general biosensing systems to make multiple-detecting possible. 
     Although preferred embodiments of the present invention are described with reference to accompanying drawings, it will be apparent by a person having an ordinary skill in the art that the scope of the present invention is not limited thereto and diverse modifications are also possible. Therefore, the scope of the present invention should be determined by the accompanying claims and their equivalents.