Case Studies

Don't take our word for it, here is a selection of real examples of how organisations use Mass Spec solututions to solve difficult challenges.

Rapid Analysis of Drugs and Explosives

Canadian Border Services Agency publishes paper advocating Mass Spec Scentinel's novel approach

Government agencies across the globe continuously evaluate security equipment, which is employed in Drugs and Explosives detection applications. Security equipment can be broadly divided into two categories: ‘bulk’ detectors such as metal detectors or X-Ray scanners, which rely on the presence of a significant amount of a material; and ‘trace’ detectors, such as ‘sniffer’ systems, which detect the presence of minute quantities of a threat material which may remain after handling illicit materials.

Trace detectors are used for explosives detection at locations such as airports, stadia or public buildings, and for drugs detection at ports of entry or in nightclubs. Whether the need be for the detection of drugs, explosives or even chemical warfare agents, the authorities must determine the efficacy of the various solutions proposed to address terrorist or criminal threats. To do this, governments must undertake tests to determine the limit of detection of the equipment proposed to a range of target analytes.

Recent work by Tam et al of the Canada Border Services Agency (CBSA) has advocated the use of the ‘Scentinel’ system to massively reduce the time required to obtain results. Government bodies like the CBSA regularly conduct hundreds of experiments to understand the performance of the expanding number of trace detectors available commercially.  New iterations of existing designs, not to mention urgent requirements to study new drugs or explosives that may come to light, exacerbate the number of experiments required.

The CBSA paper concluded that the Scentinel system desorber is highly efficient for a range of explosives, and that the results it produces are quantitative (i.e. the instrument response is directly proportional to the amount of explosive present). The CBSA confirmed that the analysis undertaken by the Scentinel takes a few minutes compared to the many hours required for conventional analysis and that no sample pre-treatment is required (no solvents, no derivatisation, or filtration).

The Scentinel is designed and manufactured by Bristol based Mass Spec Analytical Ltd. The instrument is based on an ABSciex triple quadrupole tandem mass spectrometer, which has been modified to incorporate a thermal desorption sample inlet system. The device simply heats samples to evaporate the compounds of interest, and draws the vapour into the mass spectrometer for analysis. This enables target analytes, such as drugs and explosives, to be analysed within seconds without the extensive sample preparation required for analysis by Gas chromatography–mass spectrometry (GCMS), even if they are in the presence of significant amounts of dirt and grease. Compounds are separated within the mass spectrometer itself, completely eliminating the need for chromatography. Tandem mass spectrometers are essentially two mass spectrometers back to back. The first is used to separate the compounds of interest according to their molecular mass. The substance is then broken up before characteristic fragments are looked for by the second mass spectrometer. This type of analysis has been called ‘fast and dirty’, since detection is achieved very rapidly with no sample clean-up, precisely the reason why its use has gained popularity with the CBSA and other authorities tasked with evaluating trace detector technologies.

The approach of directly analysing materials by thermal desorption tandem mass spectrometry (TD-MSMS) has also been successfully applied to the forensic analysis of drugs of abuse. For many years, Mass Spec Analytical Ltd. has provided an analysis service to law enforcement agencies, both in the UK and overseas. Often, the authorities wish to know whether a particular item is contaminated with a certain substance; for example, “is this jacket contaminated with amphetamine?” They are not necessarily interested in whether other substances may also be present. This is ideally suited to the use of TD-MSMS, where target compounds (in this case amphetamine) are looked for. The conventional method of analysis would be to shake the garment over a clean surface, collect the dust, extract it using a solvent , filter the extract and finally analyse it by GCMS. Alternatively, a swatch could be cut from the garment and extracted in a similar way. Either way, the total analysis time would be in excess of an hour. By contrast, by bringing the garment into contact with a moving belt that goes directly into a TD-MSMS device, the same result can be obtained in a matter of seconds. Not only that, but TD-MSMS is inherently more sensitive than GCMS (lower amounts can be detected) and by applying different areas of the jacket to the belt (sleeves, cuffs, inside and outside of pockets, etc.) far more information can be obtained in a much shorter time than it takes to conduct a single analysis by GCMS.

To date, the TD-MSMS technique has been most widely applied to the analysis of paper money for traces of drugs. Early methods of analysis relying on GCMS have now been almost entirely superseded by the use of TD-MSMS.

Chromatography free analytical solutions, coupled with the use of tandem mass spectrometry, are increasingly gaining acceptance in the field of analytical chemistry. The CBSA requirement for testing explosives detectors is just one such application; many more await discovery.


 

 

Comparison of Electrical Insulation Tapes

A police search of two addresses resulted in the seizure of two exhibits containing bundles of banknotes, each secured with black electrical insulation tape. A male suspect claimed three of the bundles of banknotes; a related female suspect claimed two of the bundles of banknotes. A roll of black electrical insulation tape was recovered from the male suspect. Both the male and female suspects stated that the same tape had been used to secure their respective bundles.

Background
A police search of two addresses resulted in the seizure of two exhibits containing bundles of banknotes, each secured with black electrical insulation tape. A male suspect claimed three of the bundles of banknotes; a related female suspect claimed two of the bundles of banknotes. A roll of black electrical insulation tape was recovered from the male suspect. Both the male and female suspects stated that the same tape had been used to secure their respective bundles.

Analytical approach
The banknotes were analysed by Atmospheric Pressure Chemical Ionisation Thermal Desorption Tandem Mass Spectrometry (MS/MS) for the presence of traces of illicit drugs. A small section of the electrical insulation tape securing each bundle and from the roll was removed and washed with a chloroform solvent to extract the glue. The pieces of tape were then analysed by Elemental Analysis – Isotope Ratio Mass Spectrometry (IRMS) to determine if it was possible to distinguish the tapes from one another or establish whether they had all come from the same source.

Result
Analysis of the banknotes by MS/MS revealed that the rolls of banknotes claimed by the male suspect were unusually contaminated with amphetamine. The banknotes claimed by the female suspect showed no unusual illicit drug contamination.

Analysis of the pieces of tape confirmed the roll of tape seized from the male suspect could not be distinguished from the tape securing his banknotes. The tape securing the female suspect’s banknotes, however, was readily distinguished and thus had not come from the same roll.

 

Conspiracy to supply Class A drugs

Police searched of a number of separate addresses and seized substantial quantities of heroin, crack cocaine and drug related paraphernalia.

During the arrests and searches cash, clothing, mobile phones, scales, and motor vehicles were seized. Nail clippings and hand swabs were also taken from the suspects.

Taking an analytical approach

The following exhibits were submitted to MSA for analysis:

• Banknotes
• Mobile phones
• Clothing
• Nail clippings
• Cotton swabs of suspects’ hands
• Lint brush swabs of a vehicle

All of the exhibits were analysed using MS/MS for the presence of traces of illicit drugs.

Findings

The following substances were found:

• Unusual diamorphine (heroin) contamination was detected on the banknotes.
• Unusual amounts of illicit drugs were detected on a number of the mobile phones.
• Unusual cocaine contamination was detected on the swabs taken from the vehicle.
• Traces of illicit drugs (predominantly cocaine and heroin) were also detected on the clothing, hand swabs and nail clippings taken from the suspects.

Result
In September 2006 the four suspects were convicted of Conspiracy to Supply the Class A controlled drugs heroin and cocaine. They received custodial sentences and orders for forfeiture of property were made.

The Comparison of Cannabis Resin and Packaging

A Police search of a warehouse uncovered a number of 220g blocks of cannabis resin. In a different area of the warehouse packaging material, comprising plastic bags and brown parcel tape were discovered.

Although the packaging was the approximate shape of the blocks of cannabis resin there was no evidence to link the two. 

Vapours Analysis - an analytical approach
Samples of the cannabis resin and the packaging material were submitted for analysis. Vapours were collected from the exhibits and concentrated onto an adsorbent polymer. The vapours were then analysed by combined gas chromatography – mass spectrometry (GC / MS) to identify the individual chemical components present in the vapours.

The findings
Analysis of the vapours collected from the cannabis resin identified the presence of the compounds which give cannabis its characteristic odour [e.g. alpha and beta pinene (P), limonene (L) and caryophyllene (C)].

Analysis of the vapours collected from the packaging material identified the same compounds characteristic of cannabis resin (below). Some additional compounds collected from the packaging (*) result from the adhesive present on the parcel tape.

The logical conclusion from these analytical data is that the packaging material found in the warehouse had been used to contain cannabis resin of a similar type to that found elsewhere in the warehouse.

 

Cash Seizure under the Proceeds of Crime Act

In November 2005 officers seized £1.1 million cash. Two suspects were arrested and charged with offences contrary to the Proceeds of Crime Act 2002. Two bags containing approximately £270,000 cash were submitted to Mass Spec for analysis.

Analytical approach
The banknotes were analysed by MS/MS for the presence of traces of illicit drugs and a comparison was made between the seized banknotes and banknotes taken from general circulation and analysed by MSA.

Findings
The cash within one of the bags was found to be unusually contaminated with diamorphine (heroin), and the cash from the other bag was found to be unusually contaminated with THC (the active constituent of cannabis).

Result
The two suspects pled guilty to the offences and were sentenced to four years and one year imprisonment. A confiscation order for £60,000 was also made.