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A rotating platform has been developed using a centrifugal chip holder to mount the standard chips for liquid delivery achieved by centrifugal pumping. This platform allows for dynamic hybridization to be performed in the microchannels constructed in the standard chips made using the 50 mm × 75 mm glass slides which allows for fast hybridization reactions. The results show that when the oligonucleotide-oligonucleotide hybridization is performed, there is good differentiation between perfectly complementary strands over 1 bp-mismatching counterparts when the long target strand is firstly immobilized and the short probe is secondly hybridized (Method 2), but not when the short probe is first immobilized, and the long target is subsequently hybridized (Method 1). When the differentiation between immobilized ginseng PCR product strands is performed, the correct result is achievable by Method 1, after signal enhancement and addition of formamide. The use of Method 2 is successful only when the PCR strand is captured, but not immobilized. In both methods, proper differentiation is achievable using the N1Q probe, un-achievable without centrifugal hybridization.

Non-small cell lung cancer (NSCLC) accounts for ∼80-85% of all lung cancer cases, and the EML4-ALK fusion oncogene is a well-known contributor to NSCLC cases. Expensive methods such as FISH, IHC, and NGS have been used to detect the EML4-ALK fusion oncogene. Here, a cost-effective and facile method of detecting and differentiating an EML4-ALK fusion oncogene from the wild-type gene has been accomplished by DNA hybridization using the microfluidic biochip. First, oligonucleotide probes were confirmed for successful detection of immobilized sense strands. Second, capture of the sense PCR product strands (fusion and WT) and their subsequent detection and differentiation were accomplished. Our proof-of-concept study shows the ability to detect 1% fusion products, among WT ones.

Macrocyclic polyamines, or in particular dioxopolyamines, are strong receptors for analytes such as metal ions, catechol and catecholamine derivatives. In this paper, based on their interaction with a dioxopolyamine compound: 1,4,7,10-tetraazacyclotridecane-11,13-dione (or dioxo[13]aneN 4 ), we report its use as an additive in capillary electrophoresis (CE) to improve the separation resolution and selectivity of various model analytes. Using an imidazole–acetic acid electrolyte with dioxo[13]aneN 4 as the only additive, alkali metal, alkaline earth metal and NH 4 + ions can be effectively separated and detected by using CE with indirect UV detection, as opposed to the use of crown ether in which another additive, such as α-hydroxyisobutyric acid, is needed. The host–guest interaction between dioxo[13]aneN 4 and metal and NH 4 + ions can modify their electrophoretic mobilities, and therefore can be used to differentiate the various cations, especially between K + and NH 4 + , and between Sr 2+ and Ca 2+ . We have also found that dioxo[13]aneN 4 is an effective additive in CE to resolve nitrophenols and, in particular, dihydroxybenzenes. Moreover, unlike previous reports, the separation of various biogenic monoamine neurotransmitters can be achieved at neutral or physiological pH. This work demonstrates that one of the macrocyclic dioxopolyamine derivatives: dioxo[13]aneN 4 is a promising additive in CE separations for any chemical species: cationic, anionic and neutral.

Analysis of trace amounts of various hepatotoxic microcystins in marine and freshwater samples is very important since these toxins, especially microcystin-LR, have been demonstrated to have tumour-promoting activity. In this study, instead of measuring the total amount of microcystins, we developed a capillary zone electrophoretic method for the separation and detection of individual toxin standards. No additives were used for enhancement of resolution. This technique is characterized by a high separation efficiency, short analysis time and small sample volume. In order to improve the detection sensitivity, a laser-induced fluorescence detector was used, and the labelling of microcystins was accomplished through a two-step procedure. First, the microcystin standards were converted into cysteine conjugates, followed by derivatization with Fluorescein 5-Isothiocyanate (FITC). After derivatization, the FITC-labelled microcystins were directly injected, separated and detected in 8 min. This method was shown to be a promising technique for sensitive and rapid analysis of individual microcystin toxins.

Genetic variations in patients have strong impact on their drug therapies and responses because the variations may contribute to the efficacy and/or produce undesirable side effects for any given drug. The Drug Metabolizing Enzymes and Transporters (DMET) assay is a high-throughput technology by Affymetrix that is able to simultaneously genotype variants in multiple genes involved in absorption, distribution, metabolism, and excretion of drugs for subsequent clinical applications, i.e., the assay allows for a precise genetic map that can guide therapeutic interventions and avoid side effects.