Introduction and Background
Bioanalytical biotransducers comprise a fully contiguous and specifically adhered (via covalent bond formation) thin film of electroconductive polymer hydrogel fabricated on an inert interdigitated microsensor electrode array device (IME). These biotransducers serve as chemically-sensitive, solid-state detection and monitoring devices possessing surface functionality appropriate for the immobilization of your bioactive indicator molecules.
Biotransducers may be rendered biospecific by the covalent immobilization of haptens, polypeptides, enzymes, antibodies, and DNA fragments. With the associated Electroconductive Polymer Sensor Interrogation System (EPSIS 240II CS), you are provided with the computerized sensor interrogation and data acquisition hardware for the simultaneous study of the biosensor responses of these devices.
Only the Full Differential (FD) device configuration and the 10 mincron line and space dimensions are used in the manufacture of Bioanalytical Biotransducers. The FD confiiguration provides two sensory areas on the single chip allowing for comparisons between a biospecific element and its reference. The BB devices are supplied in the form of a fully packaged (P) electrode with leadwires attached and the device encapsulated using a chemically resistant epoxy resin to seal the bonding pads into a delrin electrode body.
- Different surface chemical functional groups [carboxylic acid (-COOH), primary amine (-NH2), primary alcohol (-OH), or free sulfonate (-SO3H) allows for the specific attachment and immobilization of biologically active haptens, polypeptides, enzymes, antibodies, enzyme-linked antibodies, DNA fragments, as well as inorganic and other indicator molecules that may be of interest in your research and development.
Applications of BBs
Applications of BB in research and product development include:
In chemical and biosensor research and development: The high sensitivity of these organic, polymeric, semiconducting films to changes in redox state, along with the solid state construction and small device size, make these devices ideally suited for research and development of chemical and biosensor applications.
As chemoresistive sensor elements in multi-element arays: Several differently responding, but singularly non-specific, sensor elements may be assembled into multi-element arrays for the recognition and monitoring of analytes of interest. Biosensor line of products.
Technical Specifications
Ø Chip Substrate: Schott D263 Borosilicate Glass
Dielectric Constant, Epsilon(r) at 1 MHz = 6.7
Dielectric Loss Angle, tan delta, at 1 MHz = 61 x 10-4
Electrical Resistivity (50 Hz) (250 C) = 1.6 x 108 ohm cm
Coefficient of Linear Thermal Expansion, * 20-300 = 7.2 x 10^-6 K^-1
Refractive Index at 20 C, ne ( Lambda = 546.1 nm) = 1.5249
Ø Metallization: 100 Å Ti / 1000 Å Au or Pt
Digit length, d, (microns) = 4,985
No. of digit pairs per sensor, N = 50
Digit Width, a, (microns) = 10
Interdigit Space, a, (microns) = 10
Spatial Periodicity, lambda, (microns) = 40
Zaretsky Meander Length, M, (cm) = 24.93 cm
Center Line or Serpentine Length (cm) = 49.55 cm
Cell Constant (cm^-1) = 0.040 cm^-1
Ø IME Chip Dimensions (l x w x t) for the Un-packaged Die
Monolithic, M = 1.75 x 1.00 x 0.05
Combined Differential, CD = 1.75 x 1.00 x 0.05 cm
Full Differential, FD = 1.75 x 1.00 x 0.05 cm
Electrode Body: Delrin
Encapsulant: Epoxy header. Polyimide packaged chip.
Leadwires: Color coded, 30AWG stranded copper, shielded, and PVC jacketed.
Methods
Chemoresistance responses of Bioanalytical Biotransducers may be obtained form a wide assortment of interrogation hardware. These fall into three categories.
Dedicated Electroconductive Polymer Sensor Interrogation System (EPSIS).
DC Resistance Measurements performed with:
Simple multimeters set to resistance mode with operator recording of displayed data.
Sophisticated multimeters with data logging capability or computer interface (commonly RS232, IEEE488, or USB).
Electrometers with computer interface (commonly RS232, IEEE488, or USB).
- Complex Impedance
response performed with:
Combined Function Generator and Lock-in Amplifier.
Transfer Function Analyzers.
AC-Impedance Analyzers.
Application Notes
For further information, request Application Notes or download files:
IME1 - Interdigitated Microsensor Electrodes: Applications and References.
IME2 - Conductimetric Urea Biosensor Formed From Interdigitated Microsensor Electrodes
IME3 - Care and Cleaning Procedures
Electroconductive Polymer Microsensor Electrode (EPME TM) is the tradename for a family of non-specific sensor devices developed by ABTECH.
- Bioanalytical Biotransducers is the tradename for a family of affinity and activated sensors devices developed by ABTECH.