mChip is a portable blood test device which is capable of diagnosing an infection of HIV or Syphilis [1] [2] within 15 minutes [3] and could be used effectively against HIV/AIDS in developing countries. [1] [3] [4] The mChip costs about US$ 1 [3] and the entire diagnostic kit costs about US$ 100. [3] [5] mChip was developed so that people in regions with poor health facilities can access portable diagnosis for HIV/AIDS rather than travelling long distances to go to clinics for diagnosis. [4]
Lateral flow test is one of the blood testing methods used, in which a blood sample or oral fluid is placed on a strip of paper. In this method, a colored band indicates infection.[ citation needed ]
People in lesser developed regions like the Sub-Saharan Africa are adversely affected by HIV/AIDS and have very limited access to clinical labs or hospitals. There have been estimates which indicate that there are about 22.5 million people with HIV/AIDS in such regions and hence there is a high demand for portable blood test devices. [6] Hence devices like mChip will be able to diagnose HIV/AIDS in such regions[ citation needed ]
mChip was developed by scientists at Columbia University [7] in New York City. Initial testing of this device was undertaken in a village in Rwanda, [2] [8] where, according to the World Health Organization, approximately 3 percent of the population has HIV/AIDS. [1] Of the 400 volunteers who turned up for testing, 399 were correctly diagnosed with an accuracy of nearly 100 percent. [7] [9] [10] [11] mChip was also tested for its effectiveness in diagnosing syphilis, where, out of the 67 volunteers who turned up for testing, 63 were correctly diagnosed with an accuracy of nearly 94 percent. [1] [3] The appearance of mChip resembles a credit card. [1] [5] and is estimated to cost just US$ 1. [3]
The operation of mChip is similar to that of ELISA (Enzyme-Linked Immunosorbent Assay). [2] The ELISA can be performed to evaluate either the presence of antigen or the presence of antibody in a sample. It is a useful tool for determining serum antibody concentrations such as with the HIV test. [12] The mChip contains 10 zones [5] which detect the passage of a small amount (about 1μl) of blood. [2] The results can be obtained in a color-coded format [4] in about 15 minutes. [5]
The enzyme-linked immunosorbent assay (ELISA) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay uses a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand in a liquid sample using antibodies directed against the protein to be measured. ELISA has been used as a diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries.
HIV tests are used to detect the presence of the human immunodeficiency virus (HIV), the virus that causes acquired immunodeficiency syndrome (AIDS), in serum, saliva, or urine. Such tests may detect antibodies, antigens, or RNA.
The rapid plasma reagin test is a type of rapid diagnostic test that looks for non-specific antibodies in the blood of the patient that may indicate an infection by syphilis or related non-venereal treponematoses. It is one of several nontreponemal tests for syphilis. The term reagin means that this test does not look for antibodies against the bacterium itself, Treponema pallidum, but rather for antibodies against substances released by cells when they are damaged by T. pallidum. Traditionally, syphilis serologic testing has been performed using a nontreponemal test (NTT) such as the RPR or VDRL test, with positive results then confirmed using a specific treponemal test (TT) such as TPPA or FTA-ABS. This algorithm is currently endorsed by the U.S. Centers for Disease Control and Prevention (CDC). In addition to screening for syphilis, a titer can be used to track the progress of the disease over time and its response to therapy. The traditional algorithm using an NTT followed by a TT remains the standard in many parts of the world.
The Venereal Disease Research Laboratory test (VDRL) is a blood test for syphilis and related non-venereal treponematoses that was developed by the eponymous US laboratory. The VDRL test is used to screen for syphilis, whereas other, more specific tests are used to diagnose the disease.
In immunology, seroconversion is the development of specific antibodies in the blood serum as a result of infection or immunization, including vaccination. During infection or immunization, antigens enter the blood, and the immune system begins to produce antibodies in response. Before seroconversion, the antigen itself may or may not be detectable, but the antibody is absent. During seroconversion, the antibody is present but not yet detectable. After seroconversion, the antibody is detectable by standard techniques and remains detectable unless the individual seroreverts. Seroreversion, or loss of antibody detectability, can occur due to weakening of the immune system or waning antibody concentration over time. Seroconversion refers the production of specific antibodies against specific antigens, meaning that a single infection could cause multiple waves of seroconversion against different antigens. Similarly, a single antigen could cause multiple waves of seroconversion with different classes of antibodies. For example, most antigens prompt seroconversion for the IgM class of antibodies first, and subsequently the IgG class.
A lab-on-a-chip (LOC) is a device that integrates one or several laboratory functions on a single integrated circuit of only millimeters to a few square centimeters to achieve automation and high-throughput screening. LOCs can handle extremely small fluid volumes down to less than pico-liters. Lab-on-a-chip devices are a subset of microelectromechanical systems (MEMS) devices and sometimes called "micro total analysis systems" (µTAS). LOCs may use microfluidics, the physics, manipulation and study of minute amounts of fluids. However, strictly regarded "lab-on-a-chip" indicates generally the scaling of single or multiple lab processes down to chip-format, whereas "µTAS" is dedicated to the integration of the total sequence of lab processes to perform chemical analysis.
Serology is the scientific study of serum and other body fluids. In practice, the term usually refers to the diagnostic identification of antibodies in the serum. Such antibodies are typically formed in response to an infection, against other foreign proteins, or to one's own proteins. In either case, the procedure is simple.
Point-of-care testing (POCT), also called near-patient testing or bedside testing, is defined as medical diagnostic testing at or near the point of care—that is, at the time and place of patient care. This contrasts with the historical pattern in which testing was wholly or mostly confined to the medical laboratory, which entailed sending off specimens away from the point of care and then waiting hours or days to learn the results, during which time care must continue without the desired information.
The situation with the spread of HIV/AIDS in Russia is described by some researchers as an epidemic. The first cases of human immunodeficiency virus infection were recorded in the USSR in 1985-1987. Patient zero is officially considered to be a military interpreter who worked in Tanzania in the early 1980s and was infected by a local man during sexual contact. After 1988—1989 Elista HIV outbreak, the disease became known to the general public and the first AIDS centers were established. In 1995-1996, the virus spread among injecting drug users (IDUs) and soon expanded throughout the country. By 2006, HIV had spread beyond the vulnerable IDU group, endangering their heterosexual partners and potentially the entire population.
A lateral flow test (LFT), is an assay also known as a lateral flow device (LFD), lateral flow immunochromatographic assay, or rapid test. It is a simple device intended to detect the presence of a target substance in a liquid sample without the need for specialized and costly equipment. LFTs are widely used in medical diagnostics in the home, at the point of care, and in the laboratory. For instance, the home pregnancy test is an LFT that detects a specific hormone. These tests are simple and economical and generally show results in around five to thirty minutes. Many lab-based applications increase the sensitivity of simple LFTs by employing additional dedicated equipment. Because the target substance is often a biological antigen, many lateral flow tests are rapid antigen tests (RAT or ART).
In the diagnostic laboratory, virus infections can be confirmed by a myriad of methods. Diagnostic virology has changed rapidly due to the advent of molecular techniques and increased clinical sensitivity of serological assays.
The centrifugal micro-fluidic biochip or centrifugal micro-fluidic biodisk is a type of lab-on-a-chip technology, also known as lab-on-a-disc, that can be used to integrate processes such as separating, mixing, reaction and detecting molecules of nano-size in a single piece of platform, including a compact disk or DVD. This type of micro-fluidic biochip is based upon the principle of microfluidics; to take advantage of noninertial pumping for lab-on-a-chip devices using noninertial valves and switches under centrifugal force and Coriolis effect to distribute fluids about the disks in a highly parallel order.
The Treponema pallidum particle agglutination assay is an indirect agglutination assay used for detection and titration of antibodies against the causative agent of syphilis, Treponema pallidum subspecies pallidum. It also detects other treponematoses.
Saliva testing or Salivaomics is a diagnostic technique that involves laboratory analysis of saliva to identify markers of endocrine, immunologic, inflammatory, infectious, and other types of conditions. Saliva is a useful biological fluid for assaying steroid hormones such as cortisol, genetic material like RNA, proteins such as enzymes and antibodies, and a variety of other substances, including natural metabolites, including saliva nitrite, a biomarker for nitric oxide status. Saliva testing is used to screen for or diagnose numerous conditions and disease states, including Cushing's disease, anovulation, HIV, cancer, parasites, hypogonadism, and allergies. Salivary testing has even been used by the U.S. government to assess circadian rhythm shifts in astronauts before flight and to evaluate hormonal profiles of soldiers undergoing military survival training.
Flow-through tests or immunoconcentration assays are a type of diagnostic assay that allows users to test for the presence of a biomarker, usually a specific antibody, in a sample such as blood. They are a type of point of care test, a test designed to be used by a healthcare provider at patient contact. Point of care tests often allow for rapid detection of a specific biomarker without specialized lab equipment and training; this aids in diagnosis and allows therapeutic action to be initiated more quickly. Flow-through tests began development in the early 1980s and were the first type of immunostrip to be developed, although lateral flow tests have subsequently become the dominant immunostrip point of care device.
DiaSorin is an Italian multinational biotechnology company that produces and markets in vitro diagnostics reagent kits used in immunodiagnostics and molecular diagnostics and since July 2021, it is also active in the Life Science business. The group was founded in 2000 and is headquartered in Saluggia, Italy. Its production is at several plants located in Europe and the United States: Saluggia and Gerenzano (Italy), Dietzenbach (Germany), Stillwater, Minnesota (US), Dartford (UK). Following the acquisition of Luminex, the company acquired five additional production plants located in the United States and in Canada (Toronto). The company is a constituent of the FTSE MIB index.
OraQuick is an at-home HIV test manufactured by Orasure Technologies that was approved by the United States Food and Drug Administration in 2012. It is one of only two at-home HIV tests available. OraQuick can be purchased by anyone above aged 17 over-the-counter at any major retail stores or online.
Agglutination-PCR (ADAP) is an ultrasensitive solution-phase method for detecting antibodies. Antibodies bind to and agglutinate synthetic antigen–DNA conjugates, enabling ligation of the DNA strands and subsequent quantification by qPCR. Like other Immuno-PCR (IPCR) detection methods ADAP combines the specificity of antibody-antigen recognition and the sensitivity of PCR. ADAP detects zepto- to attomoles of antibodies in 2 μL of sample with a dynamic range spanning 5–6 orders of magnitude. For example, ADAP allows to detect anti-thyroglobulin autoantibodies from human patient plasma with a 1000-fold increased sensitivity over an FDA-approved radioimmunoassay. ADAP also allows to simultaneously detect multiple antibodies in one experiment, much more than ELISA or radioimmunoassay.
Viral load monitoring for HIV is the regular measurement of the viral load of individual HIV-positive people as part of their personal plan for treatment of HIV/AIDS. A count of the viral load is routine before the start of HIV treatment.
Paper-based microfluidics are microfluidic devices that consist of a series of hydrophilic cellulose or nitrocellulose fibers that transport fluid from an inlet through the porous medium to a desired outlet or region of the device, by means of capillary action. This technology builds on the conventional lateral flow test which is capable of detecting many infectious agents and chemical contaminants. The main advantage of this is that it is largely a passively controlled device unlike more complex microfluidic devices. Development of paper-based microfluidic devices began in the early 21st century to meet a need for inexpensive and portable medical diagnostic systems.
