Graphene

Graphene, the well-publicised and now famous two-dimensional carbon allotrope, is as versatile a material as any discovered on Earth. Its amazing properties as the lightest and strongest material, compared with its ability to conduct heat and electricity better than anything else, mean that it can be integrated into a huge number of applications. Initially this will mean that graphene is used to help improve the performance and efficiency of current materials and substances, but in the future it will also be developed in conjunction with other two-dimensional (2D) crystals to create some even more amazing compounds to suit an even wider range of applications. To understand the potential applications of graphene, you must first gain an understanding of the basic properties of the material.

The first time graphene was artificially produced; scientists literally took a piece of graphite and dissected it layer by layer until only 1 single layer remained. This process is known as mechanical exfoliation. This resulting monolayer of graphite (known as graphene) is only 1 atom thick and is therefore the thinnest material possible to be created without becoming unstable when being open to the elements (temperature, air, etc.). Because graphene is only 1 atom thick, it is possible to create other materials by interjecting the graphene layers with other compounds (for example, one layer of graphene, one layer of another compound, followed by another layer of graphene, and so on), effectively using graphene as atomic scaffolding from which other materials are engineered. These newly created compounds could also be superlative materials, just like graphene, but with potentially even more applications.

After the development of graphene and the discovery of its exceptional properties, not surprisingly interest in other two-dimensional crystals increased substantially. These other 2D crystals (such as Boron Nitride, Niobium Diselenide and Tantalum (IV) sulphide), can be used in combination with other 2D crystals for an almost limitless number of applications. So, as an example, if you take the compound Magnesium Diboride (MgB2), which is known as being a relatively efficient superconductor, then intersperse its alternating boron and magnesium atomic layers with individual layers of graphene, it improves its efficiency as a superconductor. Or, another example would be in the case of combining the mineral Molybdenite (MoS2), which can be used as a semiconductor, with graphene layers (graphene being a fantastic conductor of electricity) when creating NAND flash memory, to develop flash memory to be much smaller and more flexible than current technology, (as has been proven by a team of researchers at the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland).

The only problem with graphene is that high-quality graphene is a great conductor that does not have a band gap (it can’t be switched off). Therefore to use graphene in the creation of future nano-electronic devices, a band gap will need to be engineered into it, which will, in turn, reduce its electron mobility to that of levels currently seen in strained silicon films. This essentially means that future research and development needs to be carried out in order for graphene to replace silicon in electrical systems in the future. However, recently a few research teams have shown that not only is this possible, it is probable, and we are looking at months, rather than years, until this is achieved at least at a basic level. Some say that these kinds of studies should be avoided, though, as it is akin to changing graphene to be something it is not.

In any case, these two examples are just the tip of the iceberg in only one field of research, whereas graphene is a material that can be utilized in numerous disciplines including, but not limited to: bioengineering, composite materials, energy technology and nanotechnology.

Biological Engineering

Bioengineering will certainly be a field in which graphene will become a vital part of in the future; though some obstacles need to be overcome before it can be used. Current estimations suggest that it will not be until 2030 when we will begin to see graphene widely used in biological applications as we still need to understand its biocompatibility (and it must undergo numerous safety, clinical and regulatory trials which, simply put, will take a very long time). However, the properties that it displays suggest that it could revolutionise this area in a number of ways. With graphene offering a large surface area, high electrical conductivity, thinness and strength, it would make a good candidate for the development of fast and efficient bioelectric sensory devices, with the ability to monitor such things as glucose levels, haemoglobin levels, cholesterol and even DNA sequencing. Eventually we may even see engineered ‘toxic’ graphene that is able to be used as an antibiotic or even anticancer treatment. Also, due to its molecular make-up and potential biocompatibility, it could be utilised in the process of tissue regeneration.

Optical Electronics

One particular area in which we will soon begin to see graphene used on a commercial scale is that in optoelectronics; specifically touchscreens, liquid crystal displays (LCD) and organic light emitting diodes (OLEDs). For a material to be able to be used in optoelectronic applications, it must be able to transmit more than 90% of light and also offer electrical conductive properties exceeding 1 x 106 Ω1m1 and therefore low electrical resistance. Graphene is an almost completely transparent material and is able to optically transmit up to 97.7% of light. It is also highly conductive, as we have previously mentioned and so it would work very well in optoelectronic applications such as LCD touchscreens for smartphones, tablet and desktop computers and televisions.

Currently the most widely used material is indium tin oxide (ITO), and the development of manufacture of ITO over the last few decades time has resulted in a material that is able to perform very well in this application. However, recent tests have shown that graphene is potentially able to match the properties of ITO, even in current (relatively under-developed) states. Also, it has recently been shown that the optical absorption of graphene can be changed by adjusting the Fermi level. While this does not sound like much of an improvement over ITO, graphene displays additional properties which can enable very clever technology to be developed in optoelectronics by replacing the ITO with graphene. The fact that high quality graphene has a very high tensile strength, and is flexible (with a bending radius of less than the required 5-10mm for rollable e-paper), makes it almost inevitable that it will soon become utilized in these aforementioned applications.

In terms of potential real-world electronic applications we can eventually expect to see such devices as graphene based e-paper with the ability to display interactive and updatable information and flexible electronic devices including portable computers and televisions.

Ultrafiltration

Another standout property of graphene is that while it allows water to pass through it, it is almost completely impervious to liquids and gases (even relatively small helium molecules). This means that graphene could be used as an ultrafiltration medium to act as a barrier between two substances. The benefit of using graphene is that it is only 1 single atom thick and can also be developed as a barrier that electronically measures strain and pressures between the 2 substances (amongst many other variables). A team of researchers at Columbia University have managed to create monolayer graphene filters with pore sizes as small as 5nm (currently, advanced nanoporous membranes have pore sizes of 30-40nm). While these pore sizes are extremely small, as graphene is so thin, pressure during ultrafiltration is reduced. Co-currently, graphene is much stronger and less brittle than aluminium oxide (currently used in sub-100nm filtration applications). What does this mean? Well, it could mean that graphene is developed to be used in water filtration systems, desalination systems and efficient and economically more viable biofuel creation.

Composite Materials

Graphene is strong, stiff and very light. Currently, aerospace engineers are incorporating carbon fibre into the production of aircraft as it is also very strong and light. However, graphene is much stronger whilst being also much lighter. Ultimately it is expected that graphene is utilized (probably integrated into plastics such as epoxy) to create a material that can replace steel in the structure of aircraft, improving fuel efficiency, range and reducing weight. Due to its electrical conductivity, it could even be used to coat aircraft surface material to prevent electrical damage resulting from lightning strikes. In this example, the same graphene coating could also be used to measure strain rate, notifying the pilot of any changes in the stress levels that the aircraft wings are under. These characteristics can also help in the development of high strength requirement applications such as body armour for military personnel and vehicles.

Photovoltaic Cells

Offering very low levels of light absorption (at around 2.7% of white light) whilst also offering high electron mobility means that graphene can be used as an alternative to silicon or ITO in the manufacture of photovoltaic cells. Silicon is currently widely used in the production of photovoltaic cells, but while silicon cells are very expensive to produce, graphene based cells are potentially much less so. When materials such as silicon turn light into electricity it produces a photon for every electron produced, meaning that a lot of potential energy is lost as heat. Recently published research has proved that when graphene absorbs a photon, it actually generates multiple electrons. Also, while silicon is able to generate electricity from certain wavelength bands of light, graphene is able to work on all wavelengths, meaning that graphene has the potential to be as efficient as, if not more efficient than silicon, ITO or (also widely used) gallium arsenide. Being flexible and thin means that graphene based photovoltaic cells could be used in clothing; to help recharge your mobile phone, or even used as retro-fitted photovoltaic window screens or curtains to help power your home.

Energy Storage

One area of research that is being very highly studied is energy storage. While all areas of electronics have been advancing over a very fast rate over the last few decades (in reference to Moore’s law which states that the number of transistors used in electronic circuitry will double every 2 years), the problem has always been storing the energy in batteries and capacitors when it is not being used. These energy storage solutions have been developing at a much slower rate. The problem is this: a battery can potentially hold a lot of energy, but it can take a long time to charge, a capacitor, on the other hand, can be charged very quickly, but can’t hold that much energy (comparatively speaking). The solution is to develop energy storage components such as either a supercapacitor or a battery that is able to provide both of these positive characteristics without compromise.

Currently, scientists are working on enhancing the capabilities of lithium ion batteries (by incorporating graphene as an anode) to offer much higher storage capacities with much better longevity and charge rate. Also, graphene is being studied and developed to be used in the manufacture of supercapacitors which are able to be charged very quickly, yet also be able to store a large amount of electricity. Graphene based micro-supercapacitors will likely be developed for use in low energy applications such as smart phones and portable computing devices and could potentially be commercially available within the next 5-10 years. Graphene-enhanced lithium ion batteries could be used in much higher energy usage applications such as electrically powered vehicles, or they can be used as lithium ion batteries are now, in smartphones, laptops and tablet PCs but at significantly lower levels of size and weight.

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- Related Publications -

Graphene - What Is It?

The Properties Of Graphene

The Price Of Graphene

What Is Graphene Oxide?

Reduced Graphene Oxide - What Is It? How Is It Created?

Graphene & Graphite - How Do They Compare?

CVD Graphene - Creating Graphene Via Chemical Vapour Deposition

Graphene Supercapacitors - What Are They?

Tell us what kind of graphene you need and we will produce it for you. Our knowledge, skills, experience and equipment mean that almost any need can be met and on any scale - research, pilot line and industrial. To discuss your graphene requirements:

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Honda's New Hydrogen-Powered Vehicle

UPDATE: This story was updated to add the car’s official name, Honda Clarity, which was announced at a press conference Wednesday. 

TOKYO — The most notable thing about Honda Motor's ‘s new hydrogen-powered Clarity fuel cell vehicle, unveiled Wednesday at the Tokyo Motor Show, is not the silent burst of acceleration it provides when your foot touches the pedal, or the fact that it emits nothing but water vapor from the tailpipe. It’s not even that the Clarity can go more than 400 miles between three-minute hydrogen fillings - assuming you have access to a hydrogen station.

No, the most important thing is that Honda’s new fuel cell system is one-tenth the cost of previous versions and — for the first time — fits neatly under the car’s hood, taking up no more space than a typical V-6 engine. That means two things: 1) there’s more space for passengers and cargo, and 2) the compact fuel cell power train can be used in a variety of other Honda vehicles.

This really does feel like a real leap forward in the shift toward fuel cell vehicles and a so-called “hydrogen society.”

Of course, getting the hydrogen remains a sticking point. In California and the Northeast, companies like First Element and Air Liquide are installing hydrogen stations with support from government grants as well as loans from Toyota and Honda, but the rollout to date has been slow.

Honda might have a solution, though: it’s developing a compact Smart Hydrogen Station, enabling you to use high-pressure electrolysis to produce your own hydrogen at home. There’s no word on when that might be available, but if it’s affordable, it could be a huge breakthrough in speeding the adoption of fuel cell vehicles.

The Clarity goes on sale next spring (about six months behind Toyota Motor's ‘s recently introduced Mirai fuel cell) and the automaker expects to sell far more than the 72 units sold of its previous-generation fuel cell, the FCX Clarity. Honda said the same platform will also underpin a new plug-in hybrid vehicle, coming shortly after the fuel cell vehicle’s launch. Honda said it sees plug-in hybrids as an important bridge toward hydrogen-powered fuel cells.

UPDATE: This story was updated to add the car’s official name, Honda Clarity, which was announced at a press conference Wednesday. 

TOKYO — The most notable thing about Honda Motor's ‘s new hydrogen-powered Clarity fuel cell vehicle, unveiled Wednesday at the Tokyo Motor Show, is not the silent burst of acceleration it provides when your foot touches the pedal, or the fact that it emits nothing but water vapor from the tailpipe. It’s not even that the Clarity can go more than 400 miles between three-minute hydrogen fillings - assuming you have access to a hydrogen station.

No, the most important thing is that Honda’s new fuel cell system is one-tenth the cost of previous versions and — for the first time — fits neatly under the car’s hood, taking up no more space than a typical V-6 engine. That means two things: 1) there’s more space for passengers and cargo, and 2) the compact fuel cell power train can be used in a variety of other Honda vehicles.

This really does feel like a real leap forward in the shift toward fuel cell vehicles and a so-called “hydrogen society.”

Of course, getting the hydrogen remains a sticking point. In California and the Northeast, companies like First Element and Air Liquide are installing hydrogen stations with support from government grants as well as loans from Toyota and Honda, but the rollout to date has been slow.

Honda might have a solution, though: it’s developing a compact Smart Hydrogen Station, enabling you to use high-pressure electrolysis to produce your own hydrogen at home. There’s no word on when that might be available, but if it’s affordable, it could be a huge breakthrough in speeding the adoption of fuel cell vehicles.

The Clarity goes on sale next spring (about six months behind Toyota Motor's ‘s recently introduced Mirai fuel cell) and the automaker expects to sell far more than the 72 units sold of its previous-generation fuel cell, the FCX Clarity. Honda said the same platform will also underpin a new plug-in hybrid vehicle, coming shortly after the fuel cell vehicle’s launch. Honda said it sees plug-in hybrids as an important bridge toward hydrogen-powered fuel cells.

Despite its compact size, the new fuel cell system gets a 30 percent increase in power, to 130 kilowatts, with a 700-kilometer (435 mile) range. It’s paired with a flat lithium-ion battery pack that fits under the front seats. There are two hydrogen tanks: a large one that fits behind the rear bulkhead, with a smaller one under the rear seat. The larger tank clearly cuts into trunk space, but there’s still a decent amount of room for golf bags or luggage.

Virtually every automaker is working on fuel cell vehicles; it’ll be interesting to see how they develop. Just as with hybrid vehicles a generation ago, it’s Honda and Toyota leading the way.

Full > http://tinyurl.com/jjkcq4p

Cricket Explained

Cricket is a ball game played by two teams with 11 players on each side. In a way, cricket is similar to baseball – one man throws a ball at the batsman who tries to hit it as far as possible while other players in the field try to catch the ball or stop it from going out of the field, and prevent the batsman from scoring runs. However, it is more elaborate and of longer duration than its American counterpart. Various versions of the game have evolved over the years. I will attempt to explain the game as simply as possible so as to enable the uninitiated to strike a conversation on cricket.

Cricket is a religion in India. No other sport generates such mass hysteria and madness in the country. It unites strangers and makes friends out of enemies. Streets empty out whenever India plays against a formidable opponent, especially Pakistan. It is no wonder that cricket is considered the unofficial national game of India (the official national game being field hockey).

The roots of cricket date back to the 16th century. However, the modern version of the game dates back to 1844. Today, most Commonwealth nations play professional cricket.

I will take you through the game by explaining the rules, the various formats of the game, key nations and the best international players. I hope you will enjoy this series and pick up enough knowledge to talk your way through a casual conversation on the game.

As explained above, cricket is by far the most popular sport in India and has evolved over the years: first there was only the five-day game, then came the one-day game and today there is also a three-hour game (known as “20:20”). All the formats are still in vogue in India and various tournaments are held in each format – both national and international.

Cricket is played in open fields or stadiums on a “pitch” – a rectangular ground 20.12m (22 yards) long and 3.05m wide.

It is bound at either end by the “bowling creases” and on each end are the “wickets” which are three sticks or “stumps” with two “bails” balanced on top. The aim of the batsmen is to defend the wickets and make as many “runs” between the wickets as possible; while the bowler aims to get the batsmen “out” by hitting the wicket and knocking the wooden bails balanced on top. On getting out, the batsman has to return to the pavilion and the next batsman replaces him. There are other ways of getting the batsman out: through a “catch” where a fielder or the “wicket-keeper” catches the ball while it is still in the air after being hit by the batsman, being “run-out” where the batsmen “runs” after hitting the ball (similar to baseball) and is not able to reach the “return crease” before a fielder (or the bowler), hits the wicket at either end with the ball, “LBW” (Leg Before Wicket) where the ball hits the batsman’s leg, which is blocking the wicket, “Stumped” where the wicket-keeper knocks the bails off the stumps after catching a ball that passes by the batsman without touching either the bat or the wicket while the batsman is still outside the “batting crease”, “Hit-wicket” where the batsman accidentally hits the wickets with his bat or accidentally trips and falls on the wickets.

There are two key scores in cricket; the number of runs that have been made; and the number of batsmen that have got out. The batsmen tries to get as many “runs” as possible for his team while the other team bowls. Runs can be scored by running between the wickets after hitting the ball or by hitting the ball hard enough to make it go out of the ground either touching the ground (4 runs, also known as a “boundary”) or flying out without touching the ground (6 runs, called a Sixer). The higher scoring team wins the match.

Now, we’ll talk of the oldest and the longest version of the game – the five day format popularly known as “Test Cricket”. Test Cricket usually lasts for five days with each team batting and bowling twice; at the end of which, the game can still end in a “draw” with no team winning!

Test cricket is played in “innings” during which one team attempts to score while the other team attempts to prevent the first from scoring. The competing teams alternate who is “in bat” and who is bowling. The exception to this rule is a “follow-on”. This happens if, at the end of its first innings, Team B’s total falls short of Team A’s first innings’ total by at least 200 runs, the captain of Team A can choose to order Team B to stay in bat. If he does so, Team B must commence its second batting innings immediately (i.e. following on from their last batting). Each innings lasts until all the batsmen are dismissed or until the batting team “declares” the innings over after having established a big “score” of runs.

After having explained about Test Cricket, I will explain about the faster and shorter format of the game – the One Day International Cricket (ODI). In an ODI, 50 “overs” (a set of six consecutive balls bowled in succession) are played per side between two national cricket teams.

The basic rules of cricket are followed. The Captain of the team winning the “toss” chooses to either “bat” or “bowl” (field) first. The team batting first sets the target score in 50 overs.

The innings lasts until the batting side is “all out” (i.e., 10 of the 11 batting players are “out”) or all of the first side’s allotted overs are used up. The team batting second tries to score more than the target score in order to win the match. Similarly, the side bowling second tries to bowl out the second team for less than the target score in order to win. The game is declared as a “tie” (regardless of the number of wickets lost by either team) if the number of runs scored by both teams are equal, when the second team loses all of its “wickets” (batsmen getting out) or exhausts all its overs.

ODIs were introduced in the 1970s and gained popularity because the game gets over within about 8 hours and is always action packed unlike a Test Match which can get boring at times. It is also played as a “day – night” game with one innings being played during the day and the other stretching into the night and being played in flood lights.

The popularity of One Day International Cricket (ODI) cricket  soared through the late 1980s & 1990s and peaked in the last decade. However, the latest version of the game –  Twenty20 or T20 is already beginning to dwarf the popularity of the ODIs.

The rules of cricket remain the same. The major difference is that instead of 50 overs per inning, there are only 20 overs per inning. The popularity of the game lies in its short playing hours – 75 minutes for each side. In about three hours, the result is out. This keeps the tempo of the game throughout in top gear. Formally introduced in 2003, T20 has come a long way with even a World Cup of its own.

Though India made its International T20 debut only as recently as in 2006, the game has already broken all records of popularity with the introduction of the Indian Premier League (on the lines of the English Premier League) which has taken the game to the next level of entertainment.

Erica, the 'most beautiful and intelligent' android.

*Too weird and believe I can say where this is going.

Erica enjoys the theatre and animated films, would like to visit south-east Asia, and believes her ideal partner is a man with whom she can chat easily.

She is less forthcoming, however, when asked her age. “That’s a slightly rude question … I’d rather not say,” comes the answer. As her embarrassed questioner shifts sideways and struggles to put the conversation on a friendlier footing, Erica turns her head, her eyes following his every move.

It is all rather disconcerting, but if Japan’s new generation of intelligent robots are ever going to rival humans as conversation partners, perhaps that is as it should be.

Erica, who, it turns out, is 23, is the most advanced humanoid to have come out of a collaborative effort between Osaka and Kyoto universities, and the Advanced Telecommunications Research Institute International (ATR).

At its heart is the group’s leader, Hiroshi Ishiguro, a professor at Osaka University’s Intelligent Robotics Laboratory, perhaps best known for creating Geminoid HI-1, an android in his likeness, right down to his trademark black leather jacket and a Beatles mop-top made with his own hair.

Erica, however, looks and sounds far more realistic than Ishiguro’s silicone doppelganger, or his previous human-like robot, Geminoid F. Though she is unable to walk independently, she possesses improved speech and an ability to understand and respond to questions, her every utterance accompanied by uncannily humanlike changes in her facial expression.

Erica, Ishiguro insists, is the “most beautiful and intelligent” android in the world. “The principle of beauty is captured in the average face, so I used images of 30 beautiful women, mixed up their features and used the average for each to design the nose, eyes, and so on,” he says, pacing up and down his office at ATR’s robotics laboratory. “That means she should appeal to everyone.”

She is a more advanced version of Geminoid F, another Ishiguro creation which this year appeared in Sayonara, director Koji Fukada’s cinematic adaptation of a stage production of the same name.

The movie, set in rural Japan in the aftermath of a nuclear disaster, made Geminoid F the world’s first humanoid film actor, co-starring opposite Bryerly Long. While robots in films are almost as old as cinema itself, Erica did not rely on human actors – think C-3PO – or the motion-capture technology behind, for example, Sonny from I, Robot.

Although the day when every household has its own Erica is some way off, the Japanese have demonstrated a formidable acceptance of robots in their everyday lives over the past year.

From April, two branches of Mitsubishi UFJ Financial Group started employing androids to deal with customer enquiries. Pepper, a humanoid home robot, went on sale to individual consumers in June, with each shipment selling out in under a minute.

This year also saw the return to Earth of Kirobo, a companion robot, from a stay on the International Space Station, during which it became the first robot to hold a conversation with a human in space.

And this summer, a hotel staffed almost entirely by robots – including the receptionists, concierges and cloakroom staff – opened at the Huis Ten Bosch theme park near Nagasaki, albeit with human colleagues on hand to deal with any teething problems.

But increasing daily interaction with robots has also thrown up ethical questions that have yet to be satisfactorily answered. SoftBank, the company behind Pepper, saw fit to include a clause in its user agreement stating that owners must not perform sexual acts or engage in “other indecent behaviour” with the android.

Ishiguro believes warnings of a dystopian future in which robots are exploited – or themselves become theabusers – are premature. “I don’t think there’s an ethical problem,” he says. “First we have to accept that robots are a part of our society and then develop a market for them. If we don’t manage to do that, then there will be no point in having a conversation about ethics.”

Nomura Research Institute offered a glimpse into the future with a recent report in which it predicted that nearly half of all jobs in Japan could be performed by robots by 2035.

“I think Nomura is on to something,” says Ishiguro. “The Japanese population is expected to fall dramatically over the coming decades, yet people will still expect to enjoy the same standard of living.” That, he believes, is where robots can step in.

In Erica, he senses an opportunity to challenge the common perception of robots as irrevocably alien. As a two-week experiment with android shop assistants at an Osaka department store suggested, people may soon come to trust them more than they do human beings.

Full Article > http://tinyurl.com/jzj2h2o

Reliability Concerns Regarding Probation Drug Screens

The NC Department of Public Safety (DPS) has begun relying on less accurate presumptive testing for urine screens for drugs for probation, prison, and DSS cases. The focus of this post will be probation cases, though the testing is the same for prison and DSS cases.

Testing Prior to 2014

Until February 2014, the Department of Public Safety maintained two laboratories with trained staff and EMIT analyzers (an immunoassay test) to run either initial testing or additional testing on urine that gave a positive result on an screening test. These labs tested approximately 125,000 samples per year. The North Carolina State Crime Lab uses similar equipment to the former DPS labs for presumptive toxicology testing.

Current Drug Testing Procedures

The DPS labs were closed in early 2014. On-site urine drug screening is now performed by probation officers using a presumptive test kit similar to the type of urine dip test that can be purchased over the counter at many stores. Currently, additional testing is completed by Norchem, a private lab in Arizona, only when the test subject immediately denies use of a controlled substance. If the test subject admits use, the urine specimen is discarded and a positive result is reported (See NC DPS Division of Adult Correction and Juvenile Justice – Community Corrections – Policy & Procedures – Chapter H – Section .0400 Substance Abuse Screening Program, available athttps://www.ncdps.gov/div/CC/Publications/Policy.pdf, p. 367, subsection (i)). Because the urine sample is discarded, if the test subject later denies use, the sample cannot be re-tested using more reliable methods.

Reditest and the Need for Confirmatory Testing

The Reditest Panel Dip Test (“Reditest”) is the on-site screening test currently used by probation officers. The Reditest is one of many presumptive test kits which are intended to screen for drugs in urine. The Reditest package insert which describes how to use the product states in its “Limitations” section that the test “provides only a preliminary analytical test result. A secondary analytical method must be used to obtain a confirmed result.” The instruction card for a similar product can be found here. The instructions note that gas chromatography/mass spectrometry (GC/MS) is the “preferred confirmatory method.”

Reditest and Lack of Validation and On-Site Quality Assurance and Quality Control

Reditest recommends but does not provide “positive and negative controls to be tested as good laboratory practice to confirm the test procedure and to verify proper test performance.” Reditest kits are not being validated by the end user in North Carolina. If batches of test kits are not validated, there is no check on the accuracy of kits being used in the state. Immunoassay testing performed by the DPS labs prior to 2014 revealed that on several occasions the on-site test kits shipped to probation and other offices did not work as expected and yielded either inaccurate or uninterpretable results.

To administer the Reditest, a provider dips a portion of the card in a urine sample for 15 seconds. Five minutes later the results can be obtained. The card should have a control line appear in each testing area. If any line appears in the testing section (no matter how faint), the results are negative for that screen. If a line does not appear in the testing section, the manufacturer’s website explains how to send the sample to a laboratory for confirmatory testing. Administration of these presumptive tests by probation officers instead of individuals with scientific training further complicates the potential for incorrect results.

False Positives with Reditest

Included on the package insert are a subset of clinical studies which demonstrate the preliminary nature of the test. Agreement with GCMS, a more accurate confirmatory test, ranged from 89%-99%. The numbers demonstrate the possibility for false positives. In tests such as these, a false positive is typically caused by a legal substance which the kit confuses with an illicit drug. Most commonly this involves over-the-counter medications. For example, some kits will register pseudoephedrine as methamphetamine. The FDA also notes that results from these types of tests can be affected by how the test was performed, how the urine was stored, what the person ate or drank before taking the test, and any other medications the person may have taken.

Admissibility of Screening Test Results

In State v. Carter, 765 S.E.2d 56 (N.C. App. 2014), the N.C. Court of Appeals held that field drug test kits, which are presumptive tests, are inadmissible due to their lack of reliability. The Court noted that for testing of controlled substances to be admissible, it “must be based on a scientifically valid chemical analysis[.]” To establish that a test is admissible, the party must present evidence that the test methods are sufficiently reliable. Results of these initial tests without confirmatory testing should not be admissible and should not be sufficient for the basis of revocation of probation.

Screening Tests and Workplace Testing

Use of the Reditest would not meet federal guidelines for workplace testing. The U.S. Department of Health and Human Services (HHS) 2015 Mandatory Guidelines for Federal Workplace Drug Testing requires that an initial drug test be an immunoassay or alternate technology, such as spectrometry or spectroscopy. (Section 11.9, Available athttps://www.federalregister.gov/articles/2015/05/15/2015-11523/mandatory-guidelines-for-federal-workplace-drug-testing-programs#p-426) An HHS-certified laboratory must validate an initial drug test before testing specimens. (Section 11.9) Initial test results must be confirmed by an analytical method that uses mass spectrometric identification. Such methods include gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), GC/MS/MS, LC/MS/MS] or equivalent. (Section 11.12) Only specimens that yield a positive result on initial and confirmatory tests are reported as positive results. (Section 11.17)

In North Carolina, the testing used to allege a probation violation, revoke probation or remove a child from a parent’s custody would not qualify as even an initial test in the federal employment context.

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