Nanobiosys, a four-year-old South Korean molecular diagnostics firm, has published the first description and validation study of its flagship technology, a fast, portable, and inexpensive fluidic chip-based real-time PCR instrument.
Specifically, researchers from Seoul-based Nanobiosys demonstrated that its system could diagnose influenza A/H1N1 from human clinical samples with 100 percent sensitivity and specificity, performing 30 cycles of real-time PCR in about 15 minutes.
The company has also developed an automated fluidic sample prep module for its PCR system with the intent of commercializing a fully integrated and portable molecular diagnostics platform initially for research use, food testing, and veterinary diagnostics, and eventually for human diagnostics and biodefense, according to the company's CEO.
Nanobiosys was founded in 2009, relocating its headquarters to Seoul that same year. According to its website, the company has inked licensing agreements with South Korea's Electronics and Telecommunications Research Institute and the Massachusetts Institute of Technology, although it has not disclosed the nature of these agreements.
The company's primary products are the UltraFast LabChip G2-3 real-time PCR instrument, the G2 sample prep module and, disposable plastic LabChips designed to run assays on the system.
Of these products, the G2-3 real-time PCR instrument and associated consumable chips are more fully developed, and were the subject of the validation study published in December in PLOS One.
In the paper, Nanobiosys CEO Sung-Woo Kim and colleagues described a prototype version of their platform in detail for the first time. The company fabricated its fluidic LabChip consumable using injection-molded poly-methyl methacrylate, or PMMA, the cost of which is typically no more than $0.02 per cm2. In comparison, similar chips — including some on the market — are made out of various glasses or silicon wafer, and typically cost between $0.05 and $0.40 per cm2.
The flow chips, each of which measured 72 x 25 x 1.5 mm, contained three plastic layers including inlet and outlet channels (1 mm x 250 µm) and reaction chambers (1 x 3 mm). The chip contained six fluidic channels with 15 µL reaction volumes. The inlet and outlet holes were fabricated to fit a 200 µL pipette tip for sample injection and removal.
Meantime, the UltraFast LabChip real-time PCR instrument, which weighed just 5.5 kg, comprised a thermal cycle control module, an optical detector, and integrated data-analysis software. The thermal cycler was able to perform 30 cycles of real-time PCR in 15 minutes with 0.5 °C temperature variation; and the optical detector was set to detect green fluorescence emission using 490 nm excitation and 530 nm emission filters, in order to run SYBR Green-based real-time PCR assays.
The researchers first used plasmid DNA to determine that the DNA amplification efficiency of its system was comparable to that of a Bio-Rad CFX96 real-time PCR system; and that the real-time PCR performance of its system was comparable to that of a Roche LightCycler 1.5 platform. Further, they showed that their system could detect as few as a single copy of in vitro transcribed RNA with good reproducibility – comparable to that of a tube-based real-time PCR assay performed on the Bio-Rad system.
Next, the Nanobiosys researchers evaluated a total of 85 clinical nasopharyngeal swab samples — 72 of which were previously determined to be positive and 13 of which were negative for influenza A/H1N1 infection — running SYBR Green-based real-time PCR assays on both the UltraFast LabChip system and the Bio-Rad CFX96. They analyzed the results by observing amplification curve patterns, Ct values, and gel electrophoresis.
The Nanobiosys platform was able to correctly identify all 72 positive and 13 negative samples, with comparable amplification curves and Ct values to a tube-based assay on the Bio-Rad platform. They carried out their evaluation using two independent PCR primer sets, and obtained the same results for both.
In an email to PCR Insider this week, Kim noted that the evaluation was significant because it showed that the Bionanosys platform had comparable performance to existing commercial real-time PCR systems, but has the potential to be much less expensive and more portable.
In addition, although many different companies and academic groups have been developing microfluidic chip-based assays for point-of-care molecular diagnosis of infectious diseases, Kim believes that his company's platform is a step ahead.
"Our system is real-time PCR, not conventional PCR," Kim said. "Most groups [have] reported success of PCR, not real-time PCR, on fluidic chips."
In addition, he noted that some groups have successfully demonstrated point-of-care real-time PCR, "but their systems were slow, not portable," and expensive.
"Our system is fast, compact, [has] economic running cost[s] … equivalent to or less than conventional real-time PCR system[s], and [the] system price is less expensive than BioRad and Roche’s real-time PCR machines." On this latter point, he did not provide a specific price comparison.
The PLOS One study described the use of the standalone real-time PCR instrument, but, Kim noted, the company has almost completed development of the UltraFast LabChip G2 — "a polymeric LabChip-based sample prep system that is also highly efficient compared to conventional commercialized systems. We are also generating an automated integrated system of both the polymer LabChip-based real-time PCR and sample prep systems."
According to the company's website, the G2 Sample Prep system comprises a DNA/RNA isolation instrument and plastic LabChip consumables, and can isolate nucleic acid from one to 12 samples in 10 to 15 minutes.
Meantime, the company has developed several versions of the LabChip consumable to enable multiplex real-time PCR analysis of either six or 10 samples in 16 µL reaction volumes; or 18, 48, or 96 samples in 8 µL reaction volumes.
The Nanobiosys website also indicates that the company has developed real-time PCR kits to detect Mycobacterium tuberculosis, influenza A & B, the aforementioned influenza A/H1N1, norovirus, foot-and-mouth disease, and 16 different food bacterial pathogens. However, it is unclear whether the company is currently selling these kits in its home country or anywhere else.
Kim told PCR Insider that the company first plans to commercialize the UltraFast LabChip platform and associated assays "in R&D, food pathogen, and animal diagnosis markets, and then expand in[to] human and biodefense markets." Kim also said that the company is working on assays for STDs and malaria.
Further, Kim noted that the company plans to "launch our products in [the] Korean market as a test market. Then we are going to expand … to Europe, Middle East, Asia, and America. Our primary targets will be the USA, Japan, and China."
Nanobiosys has applied for more than 30 patents worldwide for its various technologies, Kim said.
One issue that the company could face down the road, should it successfully commercialize its platform: LabChip is also the brand name of a series of microfluidic-based nucleic acid separation and analysis products sold by PerkinElmer subsidiary Caliper Life Sciences.
Kim said that Nanobiosys is aware of the other LabChip products, but noted that the full names of the products are different enough that Nanobiosys will retain its UltraFast LabChip brand name for the time being.