Print yourself a spectrometer
Ever fancied building yourself a state-of-the-art Raman spectrometer? With a nod
and a wick to British kids TV, here's one I made earlier using an unmodified
inkjet printer and some blank CDs. It sounds like science fiction but Canadian
scientists hope to do just that using a novel microfabrication technique they
have developed for printing components to make a lab-on-a-CD using standard
inkjet technology.
Near infrared speech in babies
Despite an infant's amazing sensitivity to spoken language, we know relatively
little about how this sensitivity translates at the neurological level into
language development. Near-infrared spectroscopy (NIRS) looks set to change all
that thanks to US researchers. They are exploiting the ability of NIRS to map
haemoglobin and oxygen concentrations in the brain's language centres and so
follow neuronal activity in relation to speech processing in infants.
fMRI reveals wider effects of Parkinson's disease
The common perception of Parkinson's disease is of a disorder that leads to
problems with movement, tremors, involuntary spasms, and a shuffling gait.
However, functional MRI has now confirmed that the disease can also cause
widespread abnormalities in the sense of touch and vision for sufferers. An
international team from the US and China presented their findings at the
Society for Neuroscience meeting in Atlanta on October 17.
Smelly metal
Many people notice a peculiar "metallic" smell when handling iron objects,
such as tools, utensils, door handles, railings, firearms, coins, and other
objects. But, iron untouched by human hand has a subtly different almost
garlic like smell. Dietmar Glindemann of the University of Leipzig and his
colleagues Andrea Dietrich at Virginia Polytechnic Institute and State
University, and Hans-Joachim Staerk and Peter Kuschk of the Leipzig
Environmental Research Center, Germany, have used a sophisticated analytical
process to sniff out the reason why. It transpires that the metallic smell
of iron that has been touched is a kind of body odour rather than a smelly
metal.
Cultural evolution in the X-ray lab
Cultural convergence is quicker to solve structural problems, according to
UK chemists. Samantha Chong and Maryjane Tremayne of the University of
Birmingham have combined principles from social and biological evolution to
create, what they refer to as a Cultural Differential Evolution hybrid
global optimization technique that can be used to solve crystal structures
much faster than conventional evolutionary techniques. Their new, approach
could be used to solve a variety of global optimization problems in
chemistry, nanoscience and bioinformatics.
"Pac-man" enzyme could fight Alzheimer's
The crystal structure of a protein-degrading enzyme binding its natural
substrates suggests a possible way to design drugs that controlling the
abnormal levels of proteins in sufferers of diabetes or Alzheimer's disease.
Insulin-degrading enzyme (IDE), as its name would suggest, is an enzyme that
degrades insulin, but its name belies its multitalented character as this
enzyme actually binds and cleaves a wide range of diverse substrates,
including the amyloid-beta protein fragments found in Alzheimer's disease.
Zipper chemistry flies to wins Nobel
Once again X-ray crystallography underpins the Nobel Prize for Chemistry.
This year, Stanford University's Roger Kornberg will follow in his father's
footsteps to Sweden to receive the Prize for his work on messenger RNA.
Kornberg's detailed X-ray structures of the molecular process through which
DNA is transcribed into the protein-encoding machinery of mRNA has
implications throughout medicine, molecular biology and the chemistry of
life.
Sick building analysis
Sick building syndrome may not reach the news headlines as often as they
once did, but they are still an important health and safety issue for those
who manage work place environments. Now, researchers in Sweden have carried
out a multivariate evaluation of the volatile organic compounds (VOC), such
as aldehydes, amines, and acids, present in buildings. They compared their
results for buildings in which people with non-specific building-related
symptoms (also called sick building syndrome, SBS) perceive health problems
and for buildings where they do not.
Oily deal
The extraction process used in olive oil production usually leads to the
presence of halogenated solvent residues, which taint the oil and have
implications for human health. Recent European Union rules have restricted
the acceptable levels of such residues so new sensitive and precise
analytical procedures are needed for quality control and regulatory testing
of products. Spanish researchers have turned to chemical informatics to help
them optimise the extraction-analysis process.
Metallic food control
Brazilian researchers have developed a method to analyse the metal ion
content of food products by combining X-ray spectroscopy (XRS) with a
partial least-squares (PLS) data treatment. Their approach promises to be
faster, more widely applicable to a range of food and agricultural products,
and less expensive than other methods.
Nanoparticles sharpen fMRI
New molecular tools are being developed by researchers at Massachusetts
Institute of Technology that will allow functional MRI to make the
transition from imaging gross properties of the brain to a fine-tuned
analysis based on information flow involving cells and circuits. The new
generation of nanoscale calcium contrast agents will have applications in
understanding learning, memory, and behaviour, according to the MIT team.
Not fade away
No one of whatever religious persuasion who visits the Sistine Chapel in Rome
can fail to be impressed by the results of a 20-year restoration project that
has brought Michelangelo's frescoes back to their original level of artistry.
Most notable is the brilliance of the sky blue that almost illuminates the Last
Judgement on the altar wall of the chapel. But, recent NMR analysis of the
ultramarine pigment used to produce this stunning blue suggests its tendency to
fade could see the Last Judgement and other works ultimately perish.
Resistance isn't futile
As antibiotics fall to bacterial resistance one by one, it is essential that
medicinal chemists keep ahead of the game by finding compounds with new
modes of attack. Recently a new antibiotic, platensimycin has been found to
act potently through a novel mechanism. Now, US chemists have devised a
total synthesis for this unique compound and tracked their progress using
mass spectrometry and NMR spectroscopy.
Suit you, professor
Interlocking molecules that are not "chemically bonded" to each other are a
major focus of Fraser Stoddart's team. Such supramolecular chemistry holds
the promise of being able to design and build nanoscale devices, the
components of microscopic machines and computers a thousand-fold smaller and
more powerful than any silicon chip, and potentially even creating
artificial cells that mimic biology.
A peak you reach
Rather than relying on MRI and follow-up biopsy to provide information about a
suspect abnormality in the breast, researchers in the US have demonstrated in
preliminary trials that NMR spectroscopy could be used to significantly reduce
the number of biopsies required to detect the early stages of breast cancer. NMR
can lock on to the choline peak associated with malignancy during the MRI scan.
Blue, blue, electric blue
Wide angle X-ray scattering, photoluminescence, polarizing optical microscopy,
differential calorimetry, and dielectric spectroscopy have been used to study
the optical properties of a range of blue-light emitting organic compounds. The
mechanism of the self-assembly of these oligoindenofluorenes up to the polymer,
their thermal properties, and associated molecular dynamics also reveal
important clues about their behaviour and potential for applications in organic
light-emitting diodes (OLEDS) and other devices.
Anaerobics class
A QSPR (quantitative structure-property relationship) study of the anaerobic
biodegradation of chlorophenols could lead to an improvement in the disposal of
these potentially carcinogenic industrial waste products.
Lead in China's children
Researchers in Beijing have carried out a meta-analysis of AAS and ICP-MS
results published during 1994-2004 to obtain a countrywide picture of how the
level of lead in children's blood is changing and how where they live effects
their exposure to this toxic element. Perhaps predictably, the team found that
those children living in urban or industrial regions had much higher levels of
lead than those living in rural areas.
Solving solvents
Scientists in Japan, have carried out a Raman spectroscopic study of a series of
room temperature ionic liquids using diphenylcyclopropenone (DPCP) and phenol
blue (PB) as probes to reveal information about solvent acceptor numbers. Their
results could have implications for the use of these "green" solvents.
Peptides go tubular
The highly unique crystal structure of nanotubes constructed from cyclic
peptides is revealed this month by Japanese researchers in the journal Organic
Biomolecular Chemistry. The descendents of these novel nanotubes could find a
role in future molecular electronic devices, according to the team, who allude
to the high macrodipole moment of their materials.
Forever bubbly
Air-assisted solvent extraction (AASX) process is an important new technique for
primary extraction of metals such as copper, nickel, cobalt and uranium, as well
as wastewater treatment where metal concentrations are typically low. According
to a Canadian research team it is the bubbles that play a critical role in
providing a high solvent-specific surface area and ease of phase separation.
Now, the team has used layer interferometry (in the UV-vis region) to measure
the time-dependent thickness of a film formed by blowing an air bubble in
kerosene-based solvents. They used Fourier transform infra-red spectroscopy to
determine its chemical composition.
Nano cancer scanner
X-ray imaging is a very mature, although not infallible, field of medicine, but
it does not lend itself to the detection of small tumours or their metastases.
Now, Sangeeta Bhatia in Boston, Massachusetts and colleagues at the Harvard-MIT
Division of Health Sciences and Technology hope to remedy that by using iron
oxide nanoparticles to allow MRI to visualize areas of tumor invasion.
Lighting up the near-infra-red
A novel class of lanthanide compounds that emit in the near-infra-red could open
up new possibilities for the use of NIR in biological imaging as well as leading
to materials for optical amplifiers and light-emitting diodes (LEDs) operating
at telecommunications frequencies.
The latest round up of science news from David Bradley goes live at spectroscopyNOW.com today.
Among May 15's postings:
Biomedical researchers have long thought that male sex hormones play a critical role in controlling cholesterol levels and lipids and in the development of atherosclerosis, a serious risk factor for heart disease, but new research from Wyeth Laboratories reveals the
truth...
Also, Chinese scientists have developed a new cheminformatics method for analysing the products of chemical reactions without researchers having to worry too much about any impurities that might be present.
Third up this week, coating an alloy with a biocompatible material is a key step in making implants, such as replacement hip joints, that sit comfortably with the patient's skeleton and undergo osseointegration. A relatively new technique known as surface sol-gel processing (SSP), which is related to the well-known bulk sol-gel technique, can be used to prepare bioreactive nanostructured titanium oxides for adding a thin layer of material on a prosthetic joint. Understanding how calcium is subsequently deposited and phosphate released will help in the fine-tuning of the preparation for the most effective osseointegration.
Finally, watch out for bent copper
under stress. There's plenty more news from the rest of the team on spectroscopyNOW too...
Channelling toxins
Novel treatments for high
blood pressure and other disorders
could emerge from high-resolution
solid-state NMR studies that reveal
how toxins affect the structure of
potasssium channels in the cell.
Marc Baldus of the Max Planck
Institute for Biophysical Chemistry
in Göttingen and colleagues in
France and Germany have exploited a
special protein synthesis procedure
to follow how potassium channels and
toxins combine to change the
structure of the channel.
Zeolites step-by-step
The evolution of zeolites has been followed by University of Minnesota chemical
engineer Michael Tsapatsis and colleagues using microscopy and X-ray
diffraction. Their study could lead to a new approach to designing and
synthesizing novel variations on the zeolite theme for use as molecular sieves,
catalysts, and sensors.
Analytical raft floats organic NLOs
A combination of analytical techniques has proved its worth in assessing
a series of non-linear optical materials for use in future organic
optoelectronics devices. Juan López Navarrete of the University of Malaga,
Spain, and colleagues at the University of Zaragoza-CSIC and the University of
Minnesota, Morris, USA, used UV-vis, IR, and Raman spectroscopy, nonlinear
optical (NLO) measurements, X-ray diffraction, and cyclic voltammetry to assess
the properties of a series of tricyanovinyl (TCV)-substituted oligothiophenes.
A particularly golden study
US researchers have devised what they describe as a very efficient method for
making well-defined gold nanoparticles with equal numbers of hydrophobic and
hydrophilic arms. The V-shaped arms are alternately distributed across the
surface of 2 nanometre gold core particles. The solubility of these
nanoparticles in a wide range of solvents means that they should be amenable to
further processing with various chemical modifiers. Such nanoparticles have
potential in optoelectronics, catalysis, and biomedical applications.
Cellular after image
Researchers in France have determined the analytical performance of Fourier
transform infra-red spectroscopy and imaging for concentration measurements
within biological fluids, cells, and tissues. Their results confirm that FTIR
and spectro-imaging can still play a role in analysis.
An apatite for cadmium
The mineral hydroxyapatite, like its natural counterpart found in tooth and
bone, has an affinity for the toxic heavy metal cadmium. Now, a French team has
used X-ray diffraction, ICP-AES, FTIR spectroscopy and electron microscopy to
follow the kinetics of uptake and release of this metal and demonstrated that a
solid apatite solution of cadmium is formed. Their findings could have
implications for the use of this material as a decontaminant or storage medium
for cadmium.
The root of Chinese medicine
Huángqí is a plant root used in one of the most common tonics of Chinese herbal
medicine with purported activity in cancer, diabetes, inflammation, and
nephritis, inflammation, diabetes, and cancer. As such, there is a lot of
interest in the active ingredients of this species as it might lead to novel
pharmaceuticals against a range of illnesses. Now, researchers in China have
used proton NMR to identify active components, and report their results in the
journal Magnetic Resonance Chemistry.
Mercury's online treatment
Sample pre-treatment for analysis of metals in environmental and medical samples
is often time-consuming and, worse, reagent demanding. Moreover, the usual
manual approaches in the laboratory can also cause sample contamination.
According to Portuguese researchers, these various drawbacks can be effectively
overcome by using on-line sample pre-treatment.
LED printout
There are numerous redox-active compounds that emit light under
electrical stimulation. Such materials are commonly organometallic complexes
containing a transition metal and have been developed for labelling biomolecules
for use in sensors. Related compounds are also being investigated for use in
luminescent displays. Now, researchers in The Netherlands have used inkjet
technology to "print" thin films of such materials to make new LED devices for
display and backlighting applications.
Broadband comb-over
To record a useful spectrum in a reasonable time, the spectroscopist must juggle
bandwidth, resolution, sensitivity, and acquisition times. In a technique such
as cavity-ringdown spectroscopy (CRDS), high detection limits are possible but
this is offset by a narrowing of the range of frequencies that can be followed
quickly. However, US researchers have now developed a broadband version of this
technique that neatly combs over the issue of frequency limitations and can now
achieve high sensitivity, broad spectral bandwidth, high resolution, and fast
acquisition times simultaneously. The team reports in the journal Science
a proof of principle experiment in recording CRDS spectra from the visible
to near-infrared for species such as acetylene, dioxygen, water, ammonia and
argon.
NMR
pins down Alzheimer's clue
US researchers have used NMR to demonstrate that an enzyme previously
shown to protect brain cells from the characteristic fibrous tangles associated
with Alzheimer's disease also helps inhibit formation of the amyloid peptide
plaques (APPs) seen in this disease. The team examined the relationship between
APPs and the enzyme prolyl isomerase, Pin1.
Vestigial
non-virgins
Ivan Pedrosa and colleagues at Harvard have demonstrated that magnetic
resonance imaging can help rule out a diagnosis of acute appendicitis during
pregnancy when ultrasound results are inconclusive. Appendicitis during
pregnancy can lead to numerous complications, not least because of the need for
emergency surgery. Ultrasound has been used to reveal an inflamed appendix, but
it is not always conclusive, especially in the late stages of pregnancy.
Testing
the subs
Substituted pyridines are the starting materials in the manufacture of a
wide range of chemical products from agrochemicals to pharmaceuticals. As such,
understanding the fundamentals of their structures is important in developing
synthetic schemes for new compounds containing this component.
TB's
waste disposal defeats immune system
The first detailed structure of a
crucial protein-cleaving component,
the proteasome, of the tuberculosis
bacterium has been obtained by US
researchers. The existence of a
proteasome in this microbe, only
hinted at previously, could offer
new targets for drug research to
treat the disease.
Crystallography finds missing piece of haem puzzle
The missing piece of haem chemistry has been crystallised by a Japanese team.
They report the crystal structure of the enzyme human indoleamine
2,3-dioxygenase (IDO), which splits the pyrrole ring of the amino acid L-tryptophan
and incorporates both atoms of a molecule of oxygen, a crucial step in dozens of
metabolic reactions. The discovery could have implications for other studies
involving this enzyme and medical problems with which it is associated.
Computing enzymes
Researchers in Israel are using UV-Vis spectroscopy to track the underlying
logic of enzyme systems that compute. Their work could lead to implantable
enzyme-based computers that respond to metabolic changes in the body and allow
complex drug therapies to be monitored and controlled.
The inside story of rocks and fossils
US researchers have produced the first 3D images of fossils embedded in rocks
aged between 650 and 850 million years old. The non-destructive techniques of
confocal laser scanning microscopy and Raman spectroscopy allowed them to view
the interior of ancient rocks searching for signs of microscopic fossils, such
as cell walls.
Portable IR lays David's surface bare
A compact and portable mid-IR reflectance spectrometer has been used to study
surface materials on marble non-invasively, first in the lab and then on Italian
works of art: the "Deposizione dalla Croce" by Benedetto Antelami in Parma
Cathedral and "David" by Michelangelo in the Galleria dell'Accademia in
Florence.
Swell idea for medicine
The synthesis of smart hydrogels has been tracked with proton NMR, as well as
XPS (X-ray photoemission spectroscopy) and Fourier transform infrared
spectroscopy. The new materials based on cross-linking polymers can swell and
contract in a controlled way in response to specific stimuli and could have
applications in tissue engineering and drug delivery
Electronic speed camera
A speed-trap for electrons joyriding through
single crystals based on MRI can reveal their
velocities and produce an image showing an
electron density map of the electrons in the
crystal. In a kind of cold-case re-opened, the
technique provides new evidence to show that the
electrons are not breaking Ohm's law.
A
fishy business in Croatia
Croatian scientists have obtained a profile of
heavy metals present in five species of edible
fish from the end flow of River Neretva in
Croatia using atomic absorption
spectrophotometry. Their findings suggest that
eating carnivorous fish from the region is safer
in terms of people absorbing heavy metals from a
fish diet.
NMR dataset all in a spin
NMR datasets are growing apace as researchers
take great strides in experimental techniques
with increasingly powerful spectrometers. The
average protein-structure determination, for
instance, can generate anything up to about 50
gigabytes of data. To address this problem of
how to handle burgeoning quantities of data,
researchers in the US have suggested that a new
laboratory information management systems (LIMS)
is what is needed. With such systems to hand,
NMR studies, could be scaled up still further
but not at the expense of productivity.
The A to Z of solar-powered nanomotors
A solar-powered molecular motor just nanometres
across has been designed and built by an
international team of chemists. The
sub-microscopic device could be used as the
powerhouse of a nanotech machine.
The write stuff
Australian scientists have compared evidence
obtained using infrared spectroscopy with
high-performance liquid chromatography coupled with
a chemometrics analysis and demonstrated that this
latter approach can distinguish between ballpoint
pen inks much more effectively than IR alone.
Lead poisoning risk with "hooch"
MRI reveals 'true' body shape
NMR clues to accelerated aging
Diamond superconducts, and how!
A controlled release
The world of atmospheric molecules
Radical approach to protein damage
Cellular ABC