A 1-V low power gain boosted self-cascoding current mirror OTA

Huy-Binh Le,Sang-Gug Lee 대한전자공학회 2008 대한전자공학회 워크샵 Vol.2008 No.9

Transcription of Unnatural Fluorescent Nucleotides and their Application with Graphene Oxide for the Simple and Direct Detection of miRNA

Binh Huy Le,서영준 대한화학회 2018 Bulletin of the Korean Chemical Society Vol.39 No.9

In this study we synthesized two differently sized fluorescent RNA nucleotides, rUthioTP and rUpyrTP, and examined their transcription ability using T7 RNA polymerase. The smaller rUthioTP could be incorporated and extended to produce a corresponding RNA sequence, but rUpyrTP could not. We then used this rUthioTP-containing fluorogenic transcription system, in conjunction with graphene oxide(GO), for the detection of miRNA 146a with high sensitivity and selectivity. This combination of a transcribed RNA product and GO is a simple in situ probing system for the detection of miRNA 146a?one that is less time consuming and more cost-effective.

A Long Reset-Time Power-On Reset Circuit With Brown-Out Detection Capability

Huy-Binh Le,Xuan-Dien Do,Sang-Gug Lee,Seung-Tak Ryu IEEE 2011 IEEE transactions on circuits and systems. a publi Vol.58 No.11

<P>A compact low-power on-chip power-on reset circuit with a brown-out detection capability is presented. With a pico-farad-order on-chip MOS capacitor, a long reset time is achieved. A prototype design implemented in a 0.18-μm CMOS process provides a reset signal with duration of hundreds of milliseconds. The embedded brown-out detection circuit can detect the event, as long as the brown-out duration is longer than the millisecond range. The chip consumes only 1 μA under a 1.8-V supply and occupies a 120 μm × 100 μm active area.</P>

Site-specific incorporation of multiple units of functional nucleotides into DNA using a step-wise approach with polymerase and its application to monitoring DNA structural changes

Huy Le, Binh,Nguyen, Van Thang,Seo, Young Jun unknown 2019 Chemical Communications Vol. No.

<P>We have developed a new method, a step-wise approach with polymerase, for site-specific incorporation of multiple units of functional nucleotides into DNA to form hairpin secondary structures. The fluorescence of the resulting DNA incorporating the functional nucleotides varied upon transitioning from single-strand to hairpin and duplex structures.</P>

Large-Stokes-shift-based folded DNA probing systems targeting DNA and miRNA 21 with signal amplification

Le, Binh Huy,Nguyen, Thuy-Van Thi,Joo, Han Na,Seo, Young Jun Elsevier 2018 Bioorganic & medicinal chemistry Vol.26 No.17

<P><B>Abstract</B></P> <P>Large-Stokes-shift based simple folded DNA probing system (LSFP) had a simple folded DNA structure and exhibited a large Stokes-shifted (194 nm) fluorescence signal upon excitation at a single wavelength (386 nm). This Stokes shift was achieved through a simple combination of donor and acceptor fluorophores and employing multi-FRET systematically. This unique large Stokes-shifted fluorescence signal was used to detect target DNA with large increases in the fluorescence signal (9.7–14.2 fold). This LSFP exhibited enough selectivity, distinguishing a perfectly matched sequence from the probe itself and mismatched sequences. Surprisingly, when DSN was used for signal amplification with <B>miR21P</B> probing system whose target is miRNA 21, it showed high sensitivity (13.7 aM) and selectivity (one base mismatch discrimination). This system has several advantages over other molecular beacons (MBs): (i) it is easy to design and synthesize the probing system that does not require the construction of a finely designed stem and loop, as in most MBs (this can prevent the degradation of <B>miR21P</B> itself by DSN enzyme without special backbone modification); (ii) it can control unique fluorescence, such as large Stokes-shifted fluorescence through a simple combination of donor and acceptor fluorophores; and (iii) through signal amplification using DSN, it can efficiently detect extremely small amounts of target miRNA with high sensitivity (13.7 aM).</P> <P><B>Highlights</B></P> <P> <UL> <LI> A combination of donor and acceptor displaying large Stokes-shifted fluorescence. </LI> <LI> Signal amplification using large Stokes-shifted folded DNA system with DSN enzyme. </LI> <LI> LSFP system can detect extremely small amounts of target miRNA 21 (LOD = 13.7 aM). </LI> <LI> Large Stokes-shifted folded DNA probing system has simple folded DNA structure. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A Fully On-Chip Gm-Opamp-RC Based Preamplifier for Electret Condenser Microphones

LE, Huy-Binh,RYU, Seung-Tak,LEE, Sang-Gug The Institute of Electronics, Information and Comm 2009 IEICE transactions on electronics Vol.92 No.4

<P>An on-chip CMOS preamplifier for direct signal readout from an electret capacitor microphone has been designed with high immunity to common-mode and supply noise. The Gm-Opamp-RC based high impedance preamplifier helps to remove all disadvantages of the conventional JFET based amplifier and can drive a following switched-capacitor sigma-delta modulator in order to realize a compact digital electret microphone. The proposed chip is designed based on 0.18µm CMOS technology, and the simulation results show 86dB of dynamic range with 4.5µVrms of input-referred noise for an audio bandwidth of 20kHz and a total harmonic distortion (THD) of 1% at 90mVrms input. Power supply rejection ratio (PSRR) and common-mode rejection ration (CMRR) are more than 95dB at 1kHz. The proposed design dissipates 125µA and can operate over a wide supply voltage range of 1.6V to 3.3V.</P>

Highly sensitive MicroRNA 146a detection using a gold nanoparticle–based CTG repeat probing system and isothermal amplification

Le, Binh Huy,Seo, Young Jun Elsevier 2018 Analytica chimica acta Vol.999 No.-

<P><B>Abstract</B></P> <P>We have developed a gold nanoparticle (AuNP)–based CTG repeat probing system displaying high quenching capability and combined it with isothermal amplification for the detection of <B>miRNA 146a</B>. This method of using a AuNP-based CTG repeat probing system with isothermal amplification allowed the highly sensitive (14 aM) and selective detection of <B>miRNA 146a</B>. A AuNP-based CTG repeat probing system having a hairpin structure and a dT<SUP>F</SUP> fluorophore exhibited highly efficient quenching because the CTG repeat–based stable hairpin structure imposed a close distance between the AuNP and the dT<SUP>F</SUP> residue. A small amount of <B>miRNA 146a</B> induced multiple copies of the CAG repeat sequence during rolling circle amplification; the AuNP-based CTG repeat probing system then bound to the complementary multiple-copy CAG repeat sequence, thereby inducing a structural change from a hairpin to a linear structure with amplified fluorescence. This AuNP-based CTG probing system combined with isothermal amplification could also discriminate target <B>miRNA 146a</B> from one- and two-base-mismatched miRNAs (<B>ORN 1</B> and <B>ORN 2</B>, respectively). This simple AuNP-based CTG probing system, combined with isothermal amplification to induce a highly sensitive change in fluorescence, allows the detection of <B>miRNA 146a</B> with high sensitivity (14 aM) and selectivity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Highly quenched AuNP-based CTG repeat probing system. </LI> <LI> AuNP-based CTG repeat probing system combined with isothermal amplification for the detection of miRNA 146a. </LI> <LI> This probing system was highly sensitive (14 aM) and selective for the detection of miRNA 146a. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>A AuNP-based CTG repeat probing system combined with isothermal amplification allows the highly sensitive (14 aM) and selective detection of <B>miRNA 146a</B>.</P> <P>[DISPLAY OMISSION]</P>

AuNP-CTG based probing system targeting CAG repeat DNA and RNA sequences

Le, Binh Huy,Joo, Han Na,Hwang, Do won,Kim, Kyu Wan,Seo, Young Jun Pergamon Press 2017 Bioorganic & medicinal chemistry letters Vol.27 No.16

<P><B>Abstract</B></P> <P>We have developed a AuNP-CTG based probing system that is applicable to the detection of many units of CAG repeat sequences which was synthesized by a rolling circle amplification (RCA) system with changes in fluorescence. We also demonstrate that our AuNP-CTG based probing system could transfect without using transfection reagent and detect target CAG repeat sequences in HeLa cells with dramatic changes in fluorescence. This AuNP-CTG based probing system could also be used, in conjunction with the CAG repeat RCA system, to detect target DNA. This system was so sensitive to the target DNA that it could detect even picomolar amounts with amplification of the fluorescence signal. Furthermore, we have used our gold-based CAG probing system for the detection of RNA CAG repeat sequences.</P> <P><B>Graphical abstract</B></P> <P>We have developed a AuNP-CTG based probing system that is efficient to detect CAG repeat DNA and RNA.</P> <P>[DISPLAY OMISSION]</P>

Direct incorporation and extension of a fluorescent nucleotide through rolling circle DNA amplification for the detection of microRNA 24-3P

Le, Binh Huy,Seo, Young Jun Elsevier 2018 Bioorganic & medicinal chemistry letters Vol.28 No.11

<P><B>Abstract</B></P> <P>We designed and synthesized several fluorescent nucleotides from thiophene, anthracene and pyrene, which have different sizes, and screened their incorporation and extension capability during the rolling circle amplification of DNA. The thiophene-based fluorescent nucleotide (<B>dUthioTP</B>) could highly incorporate and extended into the rolling circle DNA product, while other fluorescent nucleotides (<B>dUanthTP</B>, and <B>dUpyrTP</B>) could not. This <B>dUthioTP</B> fluorescent nucleotide could be used for the detection of <B>miRNA 24-3P</B>, which is related PRRSV. This direct labeling system during rolling circle DNA amplification exhibited an increased fluorescence signal showing gel formation for the detection of <B>miRNA 24-3P</B>. This direct labeling system is a very simple and cost-efficient method for the detection <B>miRNA 24-3P</B> and also exhibited highly sensitive and selective detection properties.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The thiophene-based fluorescent nucleotide (<B>dUthioTP</B>) could highly incorporate and extended into the rolling circle DNA product. </LI> <LI> <B>dUthioTP</B> fluorescent nucleotide could be used for the detection of <B>miRNA 24-3P</B> which is related PRRSV. </LI> <LI> <B>dUthioTP-RCA</B> direct labeling system is a very simple and cost-efficient method for the detection <B>miRNA 24-3P</B>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

T7 exo-mediated FRET-breaking combined with DSN-RNAse-TdT for the detection of microRNA with ultrahigh signal-amplification

Nguyen, Van Thang,Le, Binh Huy,Seo, Young Jun The Royal Society of Chemistry 2019 The Analyst Vol.144 No.10

<P>A DSN-RNAse-TdT-T7 exo probing system allows the detection of miRNA 21 with very high sensitivity (LOD = 2.57 fM) and selectivity-the result of (i) avoiding the false-positive signal from miRNA reacting with TdT polymerase and (ii) signal amplification occurring through a FRET-breaking mechanism involving T7 exo.</P>