Growing next generation sequencing (NGS) throughput and new, sophisticated multiplexing strategies have significantly increased the number of samples users can prepare. The demand for reproducible and reliable data requires consistency between libraries. To achieve this, the VERSA Mini NGLP, liquid handling workstation has been optimized for NGS library preparation. Using NEXTflex™ library preparation technology in conjunction with the VERSA Mini NGLP, high throughput functionality matched with superior enzyme performance outpaces and improves consistency when compared to manual library preparation.
Morrow KJ. (2011). Novel Methods Expedite Nucleic Acid Sample Prep. Genetic Engineering News. 31(1), 1,26,28
According to Aurora Biomed, its VERSA 1100 automated, multichannel, liquid-handling system maximizes accuracy, precision, and throughput while minimizing time and consumable costs. It also offers flexibility in volume range, liquid-handling modules, deck modules, and labware adapters for custom applications used in specific protocols.
Li XJ. & Li PCH. (2010). Strategies for the real-time detection of Ca2+ channel events of single cells: recent advances and new possibilities Expert Rev. Clin. Pharmacol. 3(3), 267-280
Ca2+ ion channels play key roles in cell physiology and they are important drug targets. The Ca2+ channel events are mainly measurable by fluorescent and patch clamp methods. This review summarizes the recent advances of these techniques for the detection of Ca2+ channel events and the prospect of their new directions in the near future. Conventional bulk fluorescent methods are amenable to high-throughput applications, but they are not real-time single-cell measurements, which provide kinetic data on individual cells and offer unparalleled sensitive data for rare cells. Recent advances on real-time single-cell fluorescent measurements are conducted on microfluidic chips with scalable cell-retention sites, integrated with electrical stimulation and fluorescent measuring features. Patch clamp techniques are real-time measurements conducted on single cells, but the measurements are of low throughput. Recent advances are conducted on microfluidic patch clamp chips for high-throughput applications. Future real-time single-cell Ca2+ channel event measurements will be conducted in a multiparametric manner in an integrated and automated microfluidic chip.
Liu K, Samuel M, Tillett J, Hennan JK, Mekonnen B, Soloveva V, Harrison RK, Paslay, JW, Larocque J. (2010).High-Throughput Screening for Kv1.3 Channel Blockers Using an Improved FLIPR-Based Membrane-Potential Assay Journal of Biomolecular Screening. 15:185-195
Voltage-gated K+ channels are potential drug targets for an increasing number of disease indications. Searching for compounds that modulate K+ channel activities by high-throughput screening (HTS) is becoming a standard approach in the drug discovery effort. Here the authors report an improved fluorometric imaging plate reader (FLIPR) membrane potential assay for Kv1.3 K+ channel HTS. They have found that the Chinese hamster ovary (CHO) cells have endogenous membrane electrogenic transporters that contribute to maintaining membrane potential. Blocking the recombinant K+ channels in the overexpressing CHO cell line hardly changed the membrane potential. Inhibition of the endogenous transporters is essential to achieve the required assay robustness. The authors identified the optimal assay conditions and designed a simple assay format. After an HTS campaign using this assay, various chemical series of Kv1.3 channel blockers have been identified and confirmed by the automated electrophysiological IonWorks assay. The correlation in dose response between FLIPR and IonWorks was established by biophysical modeling and experimental data. After characterization using patch-clamp recording, both use-dependent and use-independent compounds were identified. Some compounds possess nanomolar potency, indicating that the FLIPR assay is effective for successfully identifying K+ channel blockers as novel drug candidates.
Franke AA, Halm BM, Kakazu K, Li X, Custer LJ. (2009). Phytoestrogenic isoflavonoids in epidemiologic and clinical research. Drug Testing and Analysis 2009. 1:14-21
Karczewski J, Wang J, Kane SA, Kiss L, Koblan KS, Culberson C, Spencer RH. (2009). Analogs of MK-499 are differentially affected by a mutation in the S6 domain of the hERG K+ channel. Biochemical Pharmacology 2009 (77) 1561-1654
Karczewski J, Kiss L, Kane SA, Koblan KS, Lynch RS, Spencer RS. (2009).High-throughput analysis of drug binding interactions for the human cardiac channel, Kv1.5. Biochemical Pharmacology 77 177-185.
Trivedi S, Dekermendjian K, Julien R, Huang J, Lund PE, Krupp J, Kronqvist R, Larsson O, Bostwick R. (2008). Cellular HTS assays for pharmacological characterization of Na(V)1.7 modulators. Assay Drug Dev Technol. 6 (2): 167-79.
Xiong Q, Sun H & Li M (2007). Zinc pyrithione-mediated activation of voltage-gatedKCNQ potassium channels rescues epileptogenic mutants. Nat Chem Biol 3 (5): 287-96.
Gill S, Gill R, Wicks D, & Liang D (2007). A Cell-based Rb+- Flux Assay of the Kv1.3 Potassium Channel. Assay Drug Dev Technol 5(3): 373-380.
Gill S, Gill R, Xie Y, Wicks D, & Liang D (2006). Development and Validation of HTS flux assay for endogenously expressed chloride channels in a CHO-k1 cell line. Assay Drug Dev Technol 4(1): 65-71.
Sun H, Liu X, Xiong Q, Shikano S & Li M (2006). Chronic inhibition of cardiac Kir2.1 and hERG potassium channels by celastrol with dual effects on both ion conductivity and protein trafficking. Journal of Biological Chemistry.
Murphy SM, Palmer M, Poole M, Padegimas L, Hunady K, Danzig J, Gill S, Gill R, Ting A, Sherf B, Brunden K & Stricker-Krongrad A (2006).Evaluation of functional and binding assays in cells expressing either recombinant or endogenous hERG channel.J Pharmacol Toxicol Methods. 54(1):42-55.
Gill S, Gill R, Poluektov D, Wicks D, & Liang D (2005).Development and evaluation of an Automated Cell-Based Flux Assay for HTS of hERG. American Biotechnology Laboratory, 23(13): 12-15.
Langenhan JM, Peters NR, Guzei IA, Hoffman FM & Thorson JS (2005). Enhancing the anticancer properties of cardiac glycosides by neoglycorandomization. Proc Natl Acad Sci USA 102(35):12305-10.
Sorota S, Zhang XS, Margulis M, Tucker K & Priestley T (2005). Characterization of a hERG screen using the IonWorks HT: comparison to a hERG rubidium efflux screen. Assay Drug Dev Technol 3(1):47-57.
Gill S, Gill R, Wicks D, Despotovski S & Liang D (2004). Development of an HTS assay for Na+, K+-ATPase using nonradioactive rubidium ion uptake. Assay Drug Dev Technol 2(5):535-42.
Rezazadeh S, Hesketh JC & Fedida D (2004). Rb+ flux through hERG channels affects the potency of channel blocking drugs: correlation with data obtained using a high-throughput Rb+ flux assay. J Biomol Screen.
Stankovich L, Wicks D, Despotovski S & Liang D (2004). Atomic absorption spectroscopy in ion channel screening. Assay Drug Dev Technol 2(5):569-74.
Sun H, Shikano S, Xiong Q & Li M (2004). Function recovery after chemobleaching (FRAC): evidence for activity silent membrane receptors on cell surface. Proc Natl Acad Sci USA 101(48):16964-9.
Wang K, McIlvain, Tseng E, Kowal D, Jow F, Shen R, Zhang H, Shan QJ, He L, Chen D, Lu Q & Dunlop J (2004). Validation of an atomic absorption rubidium ion efflux assay for KCNQ/M-channels using the Ion Channel Reader 8000. Assay Drug Dev Technol 2(5): 525-34
Zheng W, Spencer RH & Kiss L (2004). High throughput assay technologies for ion channel drug discovery. Assay Drug Dev Technol 2(5) 543-52.
Gill S, Gill R, Lee SS, Hesketh JC, Fedida D, Rezazadeh S, Stankovich L & Liang D (2003). Flux assays in high throughput screening of ion channels in drug discovery. Assay and Drug Dev Technol 1(5):709-17.
Gill S, Gill R, Lee SS & Liang D (2003). A high throughput screening technology: Overcoming bottlenecks in ion-channel drug targets. Lab Focus, March 1, 2003.
Scott CW, Wilkins DE, Trivedi S & Crankshaw DJ (2003). A medium-throughput functional assay of KCNQ2 potassium channels using rubidium efflux and atomic absorption spectrometry. Anal Biochem 319(2):251-7.
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Parihar AS, Groebe DR, Scott VE, Feng J, Zhang XF, Warrior U, Gopalakrishnan M & Shieh CC (2003). Functional analysis of large conductance Ca2(+)-activated K(+) channels: ion flux assay studies by atomic absorption spectrometry. Assay Drug Development Technology 1(5):647-54.
Zheng W & Kiss L (2003). Screening technologies for ion channel targets in drug discovery. American Pharmaceutical Review 6(4): 85-92
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Tang W, Kang J, Wu X, Rampe D, Wang L, Shen H, Li Z, Dunnington D & Garyantes T (2001).
Xu J, Wang X, Ensign B, Li M, Wu L, Guia A & Xu J (2001). Ion-channel assay technologies: quo vadis? Drug Discov Today 6(24):1278-87.
Terstappen GC (2005).Ion Channel Screening Technologies Today. Drug Discov Today:
Terstappen GC (2004). Non radioactive rubidium ion efflux assay and its applications in drug discovery and development. Assay Drug Dev Technol 2(5):553-9.
Terstappen GC (1999). Functional analysis of native and recombinant ion channels using a high-capacity nonradioactive rubidium efflux assay. Anal Biochem 272(2):149-55.
S7B : The Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) By Human Pharmaceuticals, step 5. May 2005.