Author Archive

Graphene-DNA biosensors to detect DNA polymorphisms

The affordable and rapid testing of DNA hybridization and polymorphisms is crucial for the diagnosis of genetic and infectious diseases. DNA biosensors based on nucleic recognition represent one of the most recent technologies currently employed. Electrochemical transducers are commonly used for sensing of DNA hybridization because they are inexpensive, small and highly sensitive. However, this kind of device sees the attachment of a single DNA probe onto the electrode surface to act as recognition element for the complementary target, and an external electro-active label that recognises this complex structure is required. To avoid the use of an external electro-active label, researchers have started to use new materials.

Huiling Loo et al., Analyst, 2013

Differential pulse voltammetry to examine the oxidation of guanine on target DNA

Adeline Huiling Loo and co-workers, from the Nanyang Technological University of Singapore, used graphene, a low cost substance made of a single layer of carbon atoms densely packed. Graphene has high electron conductivity, large specific surface area and fast electron transfer, and is considered a material with a great potential for biosening applications.

The authors analysed the properties of graphene oxide, electrochemically reduced graphene oxide and thermally reduced graphene oxide and investigated for the first time the mechanisms behind physically immobilized hairpin DNA hybridization. For the label free detection of DNA hybridization and polymorphism, they employed differential pulse voltammetry and examined the oxidation of guanine on target DNA molecules hybridized with an inosine-substituted hairpin DNA probe. According to the study, graphene oxides show the best performance in terms of recognition of complementary and non-complementary DNA sequences.

To know more about this research, click on the link below. This paper will be free to read until January 9th.

An insight into the hybridization mechanism of hairpin DNA physically immobilized on chemically modified graphenes
Adeline Huiling Loo ,  Alessandra Bonanni and Martin Pumera
Analyst, 2013, 138, 467-471
DOI: 10.1039/C2AN36199J

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Analyst Issue 2 now online!

The latest issue of Analyst is now online: take a look at these beautiful covers and read all about the research behind them.

Analyst Issue 2

Front cover: Liu and Boyd, Analyst, 2013,138, 391-409

Our outside front cover features the work of Qingtao Liu and Ben J. Boyd from the Monash University, Parkville, Australia. In their critical review, the authors offer a detailed overview on the recent use of liposomes in the field of biosensors and bioanalysis.

Liposome surface structures can be modified in a way that they recognise a wide range of analytes. Thus, the possibility to translate liposomes into commercial devices for biosensing is discussed.

Liposomes in biosensors
Qingtao Liu and Ben J. Boyd
Analyst, 2013, 138, 391-409
DOI: 10.1039/C2AN36140J

The inside front cover gives a snapshot of a study from the Republic of Korea. Jong Kyu Kim and colleagues present a high performance gas sensor based on near single crystalline TiO2 array nanohelices fabricated by rotating oblique angle deposition (OAD). This new OAD method can be used to fabricate a functional electronic nose and multifunctional smart chips for in situ environmental monitoring.

Analyst Issue 2

Inside front cover: Hwang et al., Analyst, 2013,138, 443-450

A near single crystalline TiO2 nanohelix array: enhanced gas sensing performance and its application as a monolithically integrated electronic nose
Sunyong Hwang, Hyunah Kwon, Sameer Chhajed, Ji Won Byon, Jeong Min Baik, Jiseong Im, Sang Ho Oh, Ho Won Jang, Seok Jin Yoon and Jong Kyu Kim
Analyst, 2013, 138, 443-450
DOI: 10.1039/C2AN35932D

Analyst Issue 2

Back cover: Chen et al., Analyst 2013, 138, 451-460

Finally, the back cover of this issue shows wonderful pictures taken using a dual-beam focused ion beam/scanning electron microscope (FIB/SEM) system developed by Alexander Laskin and his group, from the Pacific Northwest Laboratories, USA. The researchers suggest a novel approach for particle microanalysis, including inorganic refractive materials like fly ash and mineral dust.

Chemical imaging analysis of environmental particles using the focused ion beam/scanning electron microscopy technique: microanalysis insights into atmospheric chemistry of fly ash
Haihan Chen, Vicki H. Grassian, Laxmikant V. Saraf and Alexander Laskin
Analyst, 2013, 138, 451-460
DOI: 10.1039/C2AN36318F

Along with the covers of this issue, here are some interesting HOT articles for you to take a look at:

A selective amperometric sensing platform for lead based on target-induced strand release
Feng Li, Limin Yang, Mingqin Chen, Peng Li and Bo Tang
Analyst, 2013, 138, 461-466
DOI: 10.1039/C2AN36227A

An insight into the hybridization mechanism of hairpin DNA physically immobilized on chemically modified graphenes
Adeline Huiling Loo, Alessandra Bonanni and Martin Pumera
Analyst, 2013, 138, 467-471
DOI: 10.1039/C2AN36199J

Thermal dissociation atmospheric chemical ionization ion trap mass spectrometry with a miniature source for selective trace detection of dimethoate in fruit juices
Yongzhong Ouyang, Xinglei Zhang, Jing Han, Xiali Guo, Zhiqiang Zhu, Huanwen Chen and Liping Luo
Analyst, 2013, 138, 472-479
DOI: 10.1039/C2AN36244A

These papers will be free until January 9th.

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How clean are your contact lenses?

Although silicone hydrogel contact lenses have been available since 1999, the accumulation of biological material as solid deposit on the surface of lens polymer during lenses wear is still a reason of discomfort.
With this work, Simon Brown and colleagues from the University of Wollongong, Australia, describe a method to analyse lipids directly from a contact lens using liquid extraction surface analysis coupled to mass spectrometry (LESA-MS/MS). To demonstrate the efficiency of LESA-MS/MS, the researchers analysed the lipids on 25 worn contact lenses and extracted lipids with limited degradation of the lens material in only 15 minutes.

Brown et al., Analyst 2013

Photograph and schematic diagram of the LESA process from a contact lens

Liquid extraction surface analysis allows the extraction of analytes from a surface by creating a micro-junction between a small volume of solvent at the surface and a pipette tip. The solvent is then aspirated into the pipette tip and infused onto a sensitive mass analyser.
According to the authors, this improved technique will determine the molecular composition of biological deposits and identify the lipid molecular species representing all major classes present in human tear films.

To know more about this study click on the link below.

Communication Automated surface sampling of lipids from worn contact lenses coupled with tandem mass spectrometry
Simon H. J. Brown ,  Liam H. Huxtable ,  Mark D. P. Willcox ,  Stephen J. Blanksby and Todd W. Mitchell
Analyst, 2013, Advance Article
DOI: 10.1039/C2AN36189B

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Hot articles in Analyst Issue 1

With the first issue of Analyst 2013, we also have a good number of HOT papers for you to have a read.

Articles cover a wide range of topics including improved biosensing methodologies, some interesting data on volatile biomarkers of tumour cells and this novel tattoo-based potentiometric sensor (see picture). According to Wang and co-workers, these new tattoos have a potential in measuring strenuous physical activity by monitoring the pH of the skin.

These papers will be free to read until December 12th.

Tattoo-based potentiometric ion-selective sensors for epidermal pH monitoring

Photograph of the tattoo ISE sensor. Bandodkar et al., Analyst, 2013, 138, 123-128

Electrogenerated chemiluminescence of nanomaterials for bioanalysis
Shengyuan Deng and Huangxian Ju
Analyst, 2013, 138, 43-61
DOI: 10.1039/C2AN36122A

Integration of rapid DNA hybridization and capillary zone electrophoresis using bidirectional isotachophoresis
Supreet S. Bahga ,  Crystal M. Han and Juan G. Santiago
Analyst, 2013, 138, 87-90
DOI: 10.1039/C2AN36249J

Quantification by SIFT-MS of acetaldehyde released by lung cells in a 3D model Abigail
V. Rutter ,  Thomas W. E. Chippendale ,  Ying Yang ,  Patrik Španěl ,  David Smith and Josep Sulé-Suso
Analyst, 2013,138, 91-95
DOI: 10.1039/C2AN36185J

Tattoo-based potentiometric ion-selective sensors for epidermal pH monitoring
Amay J. Bandodkar ,  Vinci W. S. Hung ,  Wenzhao Jia ,  Gabriela Valdés-Ramírez ,  Joshua R. Windmiller ,  Alexandra G. Martinez ,  Julian Ramírez ,  Garrett Chan ,  Kagan Kerman and Joseph Wang
Analyst, 2013, 138, 123-128
DOI: 10.1039/C2AN36422K

Integration of multiple components in polystyrene-based microfluidic devices part I: fabrication and characterization
Alicia S. Johnson ,  Kari B. Anderson ,  Stephen T. Halpin ,  Douglas C. Kirkpatrick ,  Dana M. Spence and R. Scott Martin
Analyst, 2013, 138, 129-136
DOI: 10.1039/C2AN36168J

Integration of multiple components in polystyrene-based microfluidic devices part II: cellular analysis
Kari B. Anderson ,  Stephen T. Halpin ,  Alicia S. Johnson ,  R. Scott Martin and Dana M. Spence
Analyst, 2013, 138, 137-143
DOI: 10.1039/C2AN36171J

Microfluidic integration of Western blotting is enabled by electrotransfer-assisted sodium dodecyl sulfate dilution
Chenlu Hou and Amy E. Herr
Analyst, 2013, 138, 158-163
DOI: 10.1039/C2AN36033K

Screening reactive metabolites bioactivated by multiple enzyme pathways using a multiplexed microfluidic system
Dhanuka P. Wasalathanthri ,  Ronaldo C. Faria ,  Spundana Malla ,  Amit A. Joshi ,  John B. Schenkman and James F. Rusling
Analyst, 2013, 138, 171-178
DOI: 10.1039/C2AN35993F

Biofuel cell-based self-powered biogenerators for online continuous monitoring of neurochemicals in rat brain
Hanjun Cheng ,  Ping Yu ,  Xulin Lu ,  Yuqing Lin ,  Takeo Ohsaka and Lanqun Mao
Analyst, 2013, 138, 179-185
DOI: 10.1039/C2AN36385B

Fast and continuous-flow separation of DNA-complexes and topological DNA variants in microfluidic chip format
Martina Viefhues ,  Jan Regtmeier and Dario Anselmetti
Analyst, 2013, 138, 186-196
DOI: 10.1039/C2AN36056J

Ultrasensitive detection of mRNA extracted from cancerous cells achieved by DNA rotaxane-based cross-rolling circle amplification
Sai Bi ,  Yangyang Cui and Li Li
Analyst, 2013,138, 197-203
DOI: 10.1039/C2AN36118C

A biosensor fabricated by incorporation of a redox mediator into a carbon nanotube/nafion composite for tyrosinase immobilization: detection of matairesinol, an endocrine disruptor
Jahangir Ahmad Rather ,  Sanaz Pilehvar and Karolien De Wael
Analyst, 2013, 138, 204-210
DOI: 10.1039/C2AN35959F

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Analyst Issue 1 now online!

The first issue of Analyst for 2013 has now gone online! Here are the three cover articles for you to enjoy.

Analyst Issue 1

Front cover: Smits et al., Analyst, 2013, 138, 111-117

On the front cover, we have a wonderful image from Nathalie Smits and colleagues from the RIKILT-Institute of Food Safety , Wageningen, The Netherlands. The team developed a new multiplex screening tool of biomarkers for recognition of recombinant bovine somatotropin. According to the reasearch, this method can be applied with high confidence to screen somatotropin abuse in cattle. To know more about this article, click on the link below:

Multiplex flow cytometric immunoassay for serum biomarker profiling of recombinant bovine somatotropin
Nathalie Gabriëlle Esther Smits, Susann Katrina Julie Ludwig, Grisha Van der Veer, Maria Gabriëlle Eleonore Gerarda Bremer and Michel Wilhelmus Franciscus Nielen
Analyst, 2013, 138, 111-117
DOI: 10.1039/C2AN35226E

On a similar subject, our inside front cover is from Stephen O’ Hagan featuring the work of  Roystone Goodacre and co-workers from the University of Manchester. This study shows how silver deposited onto copper surfaces, such as the British 2 pence coins, can be used for detection of legal or illegal substances present in solution at low concentration. The researchers used the highly fluorescent Rhodamine 6G probe to demonstrate that silver application to copper coins leads to production of substrates capable of promoting Surface Enhanced Raman Scattering (SERS). The application of different drugs to the obtained substrates was then carried out using

Analyst Issue 1

Inside front cover: Mabbott et al., Analyst, 2013, 138, 118-122

 spotting and soaking methodologies.

2p or not 2p: tuppence-based SERS for the detection of illicit materials
Samuel Mabbott ,  Alex Eckmann ,  Cinzia Casiraghi and Royston Goodacre
Analyst, 2013, 138, 118-122
DOI: 10.1039/C2AN35974J

Back cover: Lo et al., Analyst 2013, 138, 25-31

Finally, the image on the back cover of this issue showcases the work of Gregory V. Hartland and colleagues, from the University of Notre Dame, USA. In this mini-review, the authors describe  their most recent data on detecting single nano-objects using transient absorption microscopy. They highlight a few key points for implementing transient absorption microscopy and discuss advantages and disadvantages of the techniques compared to other optical absorption based methods.

Optical detection of single nano-objects by transient absorption microscopy
Shun Shang Lo ,  Mary Sajini Devadas ,  Todd A. Major and Gregory V. Hartland
Analyst, 2013, 138, 25-31
DOI: 10.1039/C2AN36097G

These cover articles are free to access for 6 weeks. And don’t forget to take a look at the Hot articles of this Issue!

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