Automated multiplexing technology in modern clinical diagnostic instrumentation

Dec. 13, 2013

Gone are the days of expensive, laborious, and subjective testing for laboratories that process large numbers of samples. Today’s multiplexing technology includes fully automated, consistent, and objective options that yield reproducible results at much faster and higher throughputs than previously possible. Laboratories have changed how they conduct diagnostic testing by implementing automated multiplexing instruments into workflows. Physicians are ultimately supplied with more consistent and reliable results for aiding in effective clinical decision-making.

Bead-based technology

Today’s automated multiplexing technology allows samples as small as 5 µL to yield dozens of individual results and coefficients of variation (CV) often well below 10%. This level of quality in test reproducibility is significant. It provides laboratorians and physicians with confidence in the results, which can be monitored over time. In addition, advances in automated multiplexing, such as a bead-based immunoassay technology, inherently carry a wide array of benefits. Laboratories looking to optimize performance and improve their return on investment have attainable and valuable solutions at their disposal.

Bead-based multiplexing immunoassays employ thousands of heterogeneous micro-magnetic spheres to efficiently detect multiple analytes from a single sample or batches of samples. Sets of beads that are color-coded with fluorescent dyes are coated with ligands specific to a given antigen or antibody. Beads are then mixed into a single reagent pack, allowing for simultaneous detection of multiple analytes from a single sample. Panels that are built to test for multiple numbers of analytes can theoretically yield thousands of sample-specific results, depending on the number of analytes targeted and the number of samples an instrument is capable of processing.

A bead-based, fully automated, random-access multiplexing platform has the potential to provide labs with options that positively impact entire business and production workflow models. The reduced turnaround times and improved lab workflows associated with automation are in and of themselves persuasive reasons enough to make the switch to automated multiplexing. Additionally, the elimination of nonspecific antibodies in an efficient wash step offered by a bead-based system improves testing reproducibility, sensitivity, and specificity, as a bead-based system eliminates many of the manual steps required of other testing methods that can increase the likelihood of erroneous results. A system featuring built-in quality assurance beads means every assay on such a platform produces consistent, accurate, and reliable results with significantly lower false-positive and false-negative rates for each patient sample. Such technology delivers increased testing capabilities, and with them, the opportunity to capitalize on potential cost savings associated with vendor and platform consolidation.

Multiplex testing for HSV 1 and 2

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are highly pathogenic infectious diseases. Type 1 is usually associated with lesions on the mouth, lips, and pharynx and is spread via infected saliva. Type 2 is usually associated with painful vesicular and ulcerative lesions in the genitals and is spread via sexual contact.1,2 Genital herpes, furthermore, can be transmitted from mother to newborn, resulting in neonatal herpes. Untreated HSV-2 can cause neurological damage and can lead to the death of the child. It is imperative for laboratories to accurately detect and classify HSV serotypes so these infectious diseases can be properly diagnosed and treated and so transmission can be prevented.

Fully automated, random-access, bead-based multiplex technology supplies results equivocal to western blot testing for HSV-1 and HSV-2, while allowing labs to take advantage of the full array of benefits associated with such instrumentation. Labs that convert to this streamlined approach are able to free up experienced lab personnel to perform more challenging tasks while the instrument produces fast, high-quality, reproducible results. Additionally, labs can also look forward to greater opportunities for platform consolidation as the introduction of new developments in assay design, such as HIV detection, are added to an already existing and comprehensive menu. Today’s automated multiplexing systems provide faster and more consistent results that ultimately impact patient care positively.

Adalto Nascimento is a marketing assistant at Bio-Rad Laboratories’ Clinical Diagnostics Division.


  1. Smith JS, Robinson NY, Age-specific prevalence of infection with herpes simplex virus types 2 and 1: a global review. J infect dis. 2002;186(10) Suppl 1:S3-28.
  2. Xu F, Sternberg MR, Kottiri BJ, et al. Trends in herpes simplex virus type 1 and type 2 seroprevalance in the United States. JAMA. 2006;296(8):964-973.