Like a computer chip that can perform millions of mathematical operations in one second, a biochip can perform thousands of biological reactions, such as decoding genes, in a few seconds. Biochips helped to dramatically accelerate the identification of the estimated 80,000 genes in human DNA, an ongoing world-wide research collaboration known as the Human genome project. Developing a biochip plat-form incorporates electronics for addressing, reading out, sensing and controlling temperature and, in addition, a handheld analyzer capable of multiparameter identification.
The biochip platform can be plugged in a peripheric standard bus of the analyzer device or communicate through a wireless channel. Biochip technology has emerged from the fusion of biotechnology and micro/nanofabrication technology. Biochips enable us to realize revolutionary new bio analysis systems that can directly manipulate and analyze the micro/nano-scale world of bio molecules, organelles and cells. ? INTRODUCTION What is biochip? A biochip is a collection of miniaturized test sites (microarrays) arranged on a solid substrate that permits many tests to be performed at the same time in order to achieve higher throughput and speed.
Biochips are any microprocessor chips that can be used in Biology. Biochip was developed in 1983 for monitoring fisheries, the rapid technological advances of the biochemistry and semiconductor fields in the 1980s led to the large scale development of biochips in the 1990s. Biochip was made by Fred Sanger and Walter Gilbert. Biochip was invented in 4G generation & the development is still continued. Biochips were largely a "platform" technology which consisted of several separate, yet integrated components. PRINCIPLE OF BIOCHIP
While designing the biochips, a semiconducting organic molecule is inserted into a protein frame work; the whole unit is fixed onto a protein support. In biochips the electrical signals can pass through the semiconducting organic molecule. Biochip THE BIOCHIP TECHNOLOGY The biochip implants system consists of two components: a transponder and a reader or scanner. The transponder is the actual biochip implant. The biochip system is radio frequency identification (RFID) system, using low-frequency radio signals to communicate between the biochip and reader.
The reading range or activation range, between reader and biochip is small, normally between 2 and 12 inches. TRANSPONDERS The transponder is the actual biochip implant. It is a passive transponder, meaning it contains no battery or energy of its own. In comparison, an active transponder would provide its own energy source, normally a small battery. Because the passive biochip contains no battery, or nothing to wear out, it has a very long life, up to 99 years, and no maintenance. Being passive, it's inactive until the reader activates it by sending it a lowpower electrical charge.
The reader "reads" or "scans" the implanted biochip and receives back data (in this case an identification number) from the biochip. The communication between biochip and reader is via low-frequency radio waves. The biochip transponder consists of four parts: 1. Computer Microchip: The microchip stores a unique identification number from 10 to 15 digits long. The storage capacity of the current microchips is limited, capable of storing only a single ID number. AVID (American Veterinary Identification Devices), claims their chips, using an nnn-nnn-nnn format, has the capability of over 70 trillio n unique numbers.
The unique ID number is "etched" or encoded via a laser onto the surface of the microchip before assembly. Once the number is encoded it is impossible to alter. The microchip also contains the electronic circuitry necessary to transmit the ID number to the "reader". 2. Antenna Coil: This is normally a simple, coil of copper wire around a ferrite or iron core. This tiny, primitive, radio antenna "receives and sends" signals from the reader or scanner. ? 3. Tuning Capacitor: The capacitor stores the small electrical charge (less than 1/1000 of a watt) sent by the reader or scanner, which activates the transponder.
This "activation" allows the transponder to send back the ID number encoded in the computer chip. Because "radio waves" are utilized to communicate between the transponder and reader, the capacitor is "tuned" to the same frequency as the reader. 4. Glass Capsule: The glass capsule "houses" the microchip, antenna coil and capacitor. It is a small capsule, the smallest measuring 11 mm in length and 2 mm in diameter, about the size of an uncooked grain of rice. The capsule is made of biocompatible material such as soda lime glass.
After assembly, the capsule is hermetically (air -tight) sealed, so no bodily fluids can touch the electr onics inside. Because the glass is very smooth and susceptible to movement, a material such as a polypropylene polymer sheath is attached to one end of the capsule. This sheath provides a compatible surface which the bodily tissue fibers bond or interconnect, resulting in a permanent placement of the biochip. The biochip is inserted into the subject with a hypodermic syringe. Injection is safe and simple, comparable to common vaccines. Anesthesia is not required nor recommended.
In dogs and cats, the biochip is usually injected behind the neck between the shoulder blades. Trovan, L td. , markets an implant, featuring a patented "zip quill", which you simply press in, no syringe is needed. THE READER: The reader consists of an "exciter" coil which creates an electromagnetic field that, via radio signals, provides the necessary energy (less than 1/1000 of a watt) to "excite" or "activate" implanted biochip. The reader also carries a receiving coil that receives the transmitted code or ID number sent back from the "activated" implanted biochip.
This all takes place very fast, in milliseconds. The reader also contains the software and components to decode the received code and display the result in an LCD disp lay. The reader can include a RS-232 port to attach a computer. ? WORKING OF A BIOCHIP The reader generates a low-power, electromagnetic field, in this case via radio signals, which "activates" the implanted biochip. This "activation" enables the biochip to send the ID code back to the reader via radio signals.
The reader amplifies the received code, converts it to digital format, decodes and displays the ID number on the reader's LCD display. The reader must normally be between 2 and 12 inches near the biochip to communicate. The reader and biochip can communicate through most materials, except metal. ? GENERAL APPLICATIONS OF BIOCHIP With a biochip tracing of a person/animal, anywhere in the world is possible: Once the reader is connected to the internet, satellite and a centralized database is maintained about the bio chipped creatures, It is always possible to trace out the personality intended.
A biochip can store and update financial, medical, demographic data, basically everything about a person: An implanted biochip can be scanned to pay for groceries, obtain medical procedures, and conduct financial transactions. Currently, the in use, implanted biochips only store one 10 to 15 digits. If biochips are designed to accommodate with more ROM & RAM. A biochip leads to a secured E-commerce System: A biochip is the possible solution to the “identification and security” dilemma faced by the digital economy.
This type of new bio-security device is capable of accurately tracking information regarding what users are doing, and who are to accurately track information regarding what users are doing, and who is actually doing it. Biochips really are potent in replacing passports, cash, and medical records: The really powered biochip systems can replace cash, passports, medical & other records. Payment system, authentication procedures may all be done by the means Biochips. BIOMEDICAL APPLICATIONS OF BIOCHIP Blood pressure sensor: In normal situations, The Blood Pressure of a healthy Human being is 120/80 mm of Hg.
A Pressure ratio lower than this is said to be “Low BP “ condition & A Pressure ratio more than this is “High BP” condition. Serious Effects will be reflected in humans during Low & High BP conditions; it may sometimes cause the death of a Person. Blood Pressure is checked with BP Apparatus in Hospitals and this is done only when the patient is abnormal. However, a continuous monitoring of BP is required in the aged people & Patients. A huge variety of hardware circuitry (sensors) is available in electronics to detect the flow of fluid. It’s always possible to embed this type of sensors into a biochip.
An integration of Pressure (Blood Flow) detecting circuits with the Biochip can make the chip to continuously monitor the blood flow rate & when the pressure is in its low or high extremes it can be immediately informed through the reader hence to take up remedial measures. Genomics : Genomics is the study of gene sequences in living organisms and being able to read and interpret them. The human genome has been the biggest project undertaken to date but there are many research projects around the world trying to map the gene sequences of other organisms.
The use of Biochip facilitate: Automated genomic analysis including genotyping, gene expression DNA isolation from complex matrices with aim to increase recovery efficiency DNA amplification by optimizing the copy number DNA hybridization assays to improve speed and stringency . Proteomics Proteome analysis or Proteomics is the investigation of all the proteins present in a cell, tissue or organism. Proteins, which are responsible for all biochemical work within a cell, are often the targets for development of new drugs. The use of Biochip facilitates: 1. High throughput proteomic analysis . Multi-dimensional micro separations (pre LC/MS) to achieve high plate number 3. Electro kinetic sample injection for fast, reproducible, samples 4. Stacking or other preconcentration methods (as a precursor to biosensors) to improve detection limits 5. Kinetic analysis of interactions between proteins to enable accurate, transport-free kinetics. Cellomics Every living creature is made up of cells, the basic building blocks of life.. Cells are used widely by for several applications including study of drug cell interactions for drug discovery, as well as in bio sensing.
The use of Biochip facilitates: 1. Design "lab-in-cell" platforms handling single or few cells with nano probes in carefully controlled environments. 2. Field/reagent based cell lyses, where the contents of the cell are expelled out by breaking the membrane, or increase the efficiency of transfixion using reagents/field. 3. Intracellular processes to obtain high quality safety/toxicity ADME/T data. Biochips can detect cancers before symptoms develop : Biochip consists of a sq. Cm array that comprises several hundred dots.
Each of these dots contains a unique protein, antibody or nucleic acid that will attach to a particular DNA sequence or antigen. Proteins are generated by a tumor in early stages. Antibodies are released to kill those proteins. In their hunt for cancer indicators, Eprogen uses a process called 2-dimesional protein fractionation. By using cancer patients own auto-antibodies as a diagnostic tool, doctors could potentially tailor treatments based on their personal autoantibody profile. ? Biochip as Oxygen sensor : The biochip can also be integrated with an oxygen sensor .
The oxygen sensor will be useful not only to monitor breathing in intensive care units, but also to check that packages of food, or containers of semiconductors stored under nitrogen gas, remain airtight. The oxygen-sensing chip sends light pulses out into the body. The light is absorbed to varying extents, depending on how much oxygen is being carried in the blood, and the chip detects the light that is left. The rushes of blood pumped by the heart are also detected, so the same chip is a pulse monitor. Biochip as Glucose Detector : The Biochip can be integrated with a glucose detector.
The chip will allow diabetics to easily monitor the level of the sugar glucose in their blood. Diabetics currently use a skin prick and a hand-held blood test, and then medicate themselves with insulin depending on the result. The system is simple and works well, but the need to draw blood means that most diabetics don't test themselves as often as they should. Although they may get away with this in the short term, in later life those who monitored infrequently suffer from blindness, loss of circulation, and other complications. The solution is more frequent testing, using a less invasive method.
The biochip will sit underneath the skin, sense the glucose level, and send the result back out by radio frequency communication. ? Brain surgery with an on-off switch : Sensing and measuring is one thing, but can we switch the body on and off? The electric pulses of active implant, made by US-based Medtronics Inc. , are directed not at the heart but at the brain. Drug therapy of Parkinson’s disease aims to replace the brain messenger dopamine, a product of brain cells that are dying. The implantation surgery is far less traumatic than thalamotomy, and if there are any post-operative problems the stimulator can simply be turned off.
Adding sound to life : The most ambitious bioengineers are today trying to add back brain functions, restoring sight and sound where there was darkness and silence. The success story in this field is the cochlear implant. The cochlear implant delivers electrical pulses directly to the nerve cells in the cochlea, the spiral-shaped structure that translates sound in to nerve pulses. The implant mimics the job of the hair cells. It splits the incoming noises into a number of channels (typically eight) and then stimulates the appropriate part of the cochlea. Experiments with lost sight :
Several groups are working on the implantable chips that mimic the action of photoreceptors, the light-sensing cells at the back of the eye. Joseph Rizzo of the Massachusetts Eye and Ear Infirmary, and John Wyatt of Massachusetts Institute of Technology have made a twenty electrode 1mm-square chip. The final setup will include a fancy camera mounted a pair of glasses. The camera will detect and encode the scene, then send it into the eye as a laser pulse, with the laser also providing the energy to drive the chip. For now the power supply comes from a wire inserted directly in the eye and, using this device, signals reaches the brain. ?