Poor quality medicines represent a potential public health threat ranging from ineffectiveness to... more Poor quality medicines represent a potential public health threat ranging from ineffectiveness to even death. Poor quality medicines could be: Degraded (Expired/ poor storage), substandard (accidental product failure) or counterfeit (deliberate product failure). Consequently, these products may contain no active pharmaceutical ingredient (API), insufficient API or even a toxic API. Poor quality medicines could be encountered anywhere which urges the need to find rapid and non-destructive methods for their identification. Handheld Raman spectroscopy offers a rapid, quick, non-destructive and mobile technique for medicines’ identification. Moreover, the Raman scattering is selective to APIs; whereas excipients are often Raman inactive.
Counterfeit and illicit tobacco may contain potentially toxic organic impurities that result in a... more Counterfeit and illicit tobacco may contain potentially toxic organic impurities that result in adverse health effects to the consumer. The aim of this work was to investigate the feasibility of the identification of organic impurities in counterfeit or illicit tobacco using attenuated total reflectance- Fourier transform infrared (ATR-FT-IR) spectroscopy.
The identification of ‘legal highs’ is challenging as they often do not match their label claim a... more The identification of ‘legal highs’ is challenging as they often do not match their label claim and contain a wide range of impurities and/or adulterants. In addition, there is a need for techniques to be on-site, rapid and non-destructive. The feasibility of using the in-built algorithms of handheld near-infrared (NIR), Raman and attenuated total reflectance Fourier transform-infrared (ATR-FT-IR) spectroscopy for the identification of ‘legal high’ substances was investigated. Spectral libraries were constructed using three substances found in ‘legal highs’ (i.e., dextromethorphan, 2-aminoindane and lidocaine) and their 50:50 mixtures with caffeine. Model dilution mixtures with caffeine (i.e., 5 – 95% m/m) and seven ‘legal high’ Internet products were used to test the method. The ‘legal high’ constituents in most of the model mixtures were identified within a minimum range of 30 – 60% m/m for NIR, 20 – 75% m/m for Raman, and 41 – 85% m/m for ATR-FT-IR. This demonstrates that simple ...
Numbers of novel psychoactive substances (NPS) have been rapidly increasing over the past few yea... more Numbers of novel psychoactive substances (NPS) have been rapidly increasing over the past few years, with unprecedented challenges on traditional drug control systems. The web has been involved in the promotion and knowledge dissemination of NPS, which are being presented online as safer/legal alternatives to illicit drugs. The physical, psychological and social harms associated with NPS have been studied so far mainly in Europe and other English speaking countries. The aim of this research is to provide knowledge on the provision of NPS information/purchase opportunities to Middle East customers, whilst monitoring the Internet in Arabic and Farsi. Web analysis/assessments were carried out in both Farsi and Arabic between 2011 and 2013. Sources were scrutinized with the help of different search engines, including Google Arabic and Google Persian, to carry out searches focusing on both NPS retailers' and social network websites. The research identified 45 NPS apparently offered f...
Swift Quantification of Fenofibrate and Tiemonium methylsulfate Active Ingredients in Solid Drugs Using Particle Induced X-Ray Emission, Aug 2011
The quantification of active ingredients (AI) in drugs is a crucial and important step in the dru... more The quantification of active ingredients (AI) in drugs is a crucial and important step in the drug quality control process. This is usually performed by using wet chemical techniques like LC-MS, UV spectrophotometry and other appropriate organic analytical methods. However, if the active ingredient contains specific heteroatoms (F, S, Cl…), elemental IBA like PIXE and PIGE techniques, using small tandem accelerator of 1-2 MV, can be explored for molecular quantification. IBA techniques permit the analysis of the sample under solid form, without any laborious sample preparations. In this work, we demonstrate the ability of the Thick Target PIXE technique for rapid and accurate quantification of both low and high concentrations of active ingredients in different commercial drugs. Fenofibrate, a chlorinated active ingredient, is present in high amounts in two different commercial drugs, its quantification was done using the relative approach to an external standard. On the other hand, Tiemonium methylsulfate which exists in relatively low amount in commercial drugs, its quantification was done using GUPIX simulation code (absolute quantification) The experimental aspects related to the quantification validity (use of external standards, absolute quantification, matrix effect,...) are presented and discussed.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2006
The quantification of the active ingredient (AI) in drugs is a crucial and important step in the ... more The quantification of the active ingredient (AI) in drugs is a crucial and important step in the drug quality control process. This is usually performed by using wet chemical techniques like LC–MS, UV spectrophotometry and other appropriate organic analytical methods. In the case of an active ingredient contains specific heteroatoms (F, S, Cl, etc.,), elemental IBA technique can be explored for molecular quantification. IBA techniques permit the analysis of the sample under solid form, without any laborious sample preparation. This is an advantage when the number of sample is relatively large.In this work, we demonstrate the ability of the thick target PIXE (TT-PIXE) and the TT-PIGE techniques for rapid and accurate quantification of celecoxib in commercial drugs. The experimental aspects related to the quantification validity are presented and discussed.
Comparison of Laboratory and Handheld Raman Instruments for The Identification of Counterfeit Medicines, Jun 1, 2011
Raman spectroscopy offers a rapid, simple, and nondestructive technique for the identification of... more Raman spectroscopy offers a rapid, simple, and nondestructive technique for the identification of counterfeit medicines. The advantages of handheld Raman spectroscopy are that it is easy to use by unskilled personnel and it can identify a test pharmaceutical product on the spot, whether the product is in solid or liquid form. However, these instruments can operate only in reflection mode, and the Raman activity of a sample is often masked by fluorescent species in the sample, especially when the analysis is made in reflection mode. The objective of this work was to compare the use of a handheld and laboratory-based Raman instruments for authentication of pharmaceutical products obtained from the world market.
Spectrochimica Acta Part A-molecular and Biomolecular Spectroscopy, 2007
A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspiri... more A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspirin (ASP), paracetamol (PAR) and salicylic acid (SAL). The method is based on the use of the first and second derivatives of the ratio spectra and measurement at zero-crossing wavelengths. The ratio spectra were obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentration of the other components are then determined from their respective calibration curves treated similarly. The described method was applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.
Emergence and Identification of New Products of Designer Drug Products from the Internet, 2011
Designer drugs represent a rapidly expanding phenomenon particularly facilitated by their Interne... more Designer drugs represent a rapidly expanding phenomenon particularly facilitated by their Internet availability. These drugs are continuously emerging as analogues of controlled substances (amfetamine, aminoindane, cathinone, phencyclidine, etc...) and once an analogue has been banned; another replacement analogue appears on the market. They are often made in unlicensed laboratories which can result in their poor quality. This highlights the importance of analysing these products through detecting both their identity and purity. However, most of the analysis methods focused on emerging analogues of cathinone and very few studied other newer analogues such as phencyclidine derivatives. This is due partly to the regulations surrounding the analysis, the time consuming analytical procedures and the technical skills involved. Analysis of these designer drugs in the literature included both the identification of drug products and monitoring of products consistency over a period of time. In all cases, the results showed that these products may contain a range of a single or mixture of components including: a designer drug, a pharmaceutical active agent, an excipient or inorganic material.
This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent ... more This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent diffusion of its new derivative methoxetamine (“Special M”; MXE). The literature search on the nonclinical/recreational use of KET and MXE was carried out in a range of medical databases. Considering the limitations of peer-reviewed information, data were integrated with a qualitative assessment of a range of websites, drug fora, and other online resources including e-newsgroups, chat rooms, mailing lists, e-newsletters, and bulletin boards. The recreational use of KET has started since its discovery in 1962. This was due to its rapid onset, short duration of action, and peculiar psychotropic effects (“K-hole”). The latter effect ranges from confusion to dissociation and depersonalization (near-death experience). However, KET abuse is often associated with physical and psychological side effects, of which the worst is urological/bladder toxicity. Recently, MXE has emerged as a legal and “bladder-friendly” KET alternative. MXE presents with the same dissociative effect of KET, but with slower onset and longer duration of action. However, MXE seems to be associated with worse side effects than KET, ranging from mood disturbances/suicidal attempts to acute cerebellar toxicity. After 50 years of its discovery, KET has led to the emergence of MXE. However, this latter derivative does not appear to be a safer alternative to KET itself.This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent diffusion of its new derivative methoxetamine (“Special M”; MXE). The literature search on the nonclinical/recreational use of KET and MXE was carried out in a range of medical databases. Considering the limitations of peer-reviewed information, data were integrated with a qualitative assessment of a range of websites, drug fora, and other online resources including e-newsgroups, chat rooms, mailing lists, e-newsletters, and bulletin boards. The recreational use of KET has started since its discovery in 1962. This was due to its rapid onset, short duration of action, and peculiar psychotropic effects (“K-hole”). The latter effect ranges from confusion to dissociation and depersonalization (near-death experience). However, KET abuse is often associated with physical and psychological side effects, of which the worst is urological/bladder toxicity. Recently, MXE has emerged as a legal and “bladder-friendly” KET alternative. MXE presents with the same dissociative effect of KET, but with slower onset and longer duration of action. However, MXE seems to be associated with worse side effects than KET, ranging from mood disturbances/suicidal attempts to acute cerebellar toxicity. After 50 years of its discovery, KET has led to the emergence of MXE. However, this latter derivative does not appear to be a safer alternative to KET itself.
ABSTRACT Counterfeit medicines are a growing threat to public health across the world and screeni... more ABSTRACT Counterfeit medicines are a growing threat to public health across the world and screening methods are needed to allow their rapid identification. A counterfeiter must duplicate both the physical characteristics and the chemical content of a proprietary product to avoid it being detected as a counterfeit product and this is almost impossible to get right. Counterfeit proprietary medicines are, therefore, relatively easy to identify by near infrared (NIR) spectroscopy which can detect physical as well as chemical differences between products by simple spectral comparison. Identifying generic products is more difficult as they use different excipients in the tablet or capsule matrix. Nevertheless, using appropriate models and a large library, NIR spectroscopy can detect counterfeit generic versions. Detecting sub-standard proprietary medicines can be carried out with NIR spectroscopy models and the most widely used is partial least squares regression (PLSR). General rules for generating accurate quantitative models are easy to describe. Quantifying the active pharmaceutical ingredient (API) in generic products can also be carried out using PLSR models with calibration samples generated by manufacturing laboratory samples or by collecting many generic versions of a medicine so as to obtain a good range of the API content in tablets and capsules. Using hand-held instruments or mobile laboratories allows NIR spectrometers to be taken to places where analyses may be made quickly, rather than taking the samples to a laboratory. This has the enormous advantage that the screening of large numbers of samples may be made in pharmacies and wholesalers. Imaging can bring a whole new dimension to NIR spectroscopy to allow the identification of the API and individual excipients as well as measuring the particle sizes of components and giving a measure of the homogeneity of the matrix. The effect of water on potential misidentifications may be obviated by only using blister-packed samples, having large spectral libraries subjected to different humidities or omitting the spectral region where water absorbs.
Identification of Counterfeit Medicines from The Internet and the World Market Using Near-Infrared Spectroscopy, Aug 23, 2011
Pharmaceutical counterfeiting is a life threatening problem affecting all countries. Counterfeit ... more Pharmaceutical counterfeiting is a life threatening problem affecting all countries. Counterfeit medicines may be encountered anywhere in conventional markets or from the Internet. This paper proposes a rapid and non-destructive near-infrared spectroscopic method for the identification of counterfeit medicines using the minimum number of authentic samples. As little as twenty spectra from ten tablets from a batch are required to compare a test sample to its authentic counterpart. In this respect, tablets are measured as received and the correlation coefficient of the SNV-D2 spectra between the authentic sample and the test sample is determined. A correlation coefficient of lower than 0.95 indicates that the batch fails identification. In this case, if enough authentic samples are available, principal component analysis (PCA) could be applied. The PCA scores plot of the authentic and counterfeit samples with the 95% equal frequency ellipses drawn around the authentic sample set is effective in identifying counterfeits. The method could identify 82 known counterfeit medicines out of 201 medicines supplied from the Internet and the World market. However, it is still a comparative method to identify potential counterfeits and cannot identify products without authentic samples.
Identification of novel psychoactive substances (NPS) using hyphenated mass spectrometric techniques, Mar 1, 2012
The abuse of novel psychoactive substances (NPS) has been increasing over the last few years espe... more The abuse of novel psychoactive substances (NPS) has been increasing over the last few years especially as these products have become so readily available through the Internet. These products are emerging mostly as analogues or precursors of well-known drugs of abuse, such as amphetamine. However, a major problem that is more complicated than their abusive potential is that these products may not contain what is on the label. In fact, they have been shown to contain a mixture of drugs and excipients that may be toxic or even lethal. The number of deaths caused by NPS products has been increasing over the last year. This increase stimulates the need for sensitive techniques to identify these substances and detect any organic impurity in their products. Hyphenated mass spectrometric techniques, such as gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS) offer some advantages. These techniques can both separate the constituents as well as confirm the chemical identity of the individual constituents in the product.
Laboratory versus handheld instruments: What you gain and what you loose, Aug 27, 2012
The objective of this work is to compare handheld to laboratory-based Raman instruments for the i... more The objective of this work is to compare handheld to laboratory-based Raman instruments for the identification of counterfeit medicines obtained from the world market. More than 200 tablets of proprietary and generic pharmaceutical products were obtained worldwide. Handheld Raman spectroscopy offered many advantages with respect to cost, rapidity, mobility, operation in wide temperature ranges, on-spot identification of materials and ease of use by non-skilled personnel. However, there were still many drawbacks associated with the use of handheld Raman instruments related to spectral quality, fluorescence and Raman activity. However, this did not affect the accuracy of identification.
Poor quality medicines represent a potential public health threat ranging from ineffectiveness to... more Poor quality medicines represent a potential public health threat ranging from ineffectiveness to even death. Poor quality medicines could be: Degraded (Expired/ poor storage), substandard (accidental product failure) or counterfeit (deliberate product failure). Consequently, these products may contain no active pharmaceutical ingredient (API), insufficient API or even a toxic API. Poor quality medicines could be encountered anywhere which urges the need to find rapid and non-destructive methods for their identification. Handheld Raman spectroscopy offers a rapid, quick, non-destructive and mobile technique for medicines’ identification. Moreover, the Raman scattering is selective to APIs; whereas excipients are often Raman inactive.
Counterfeit and illicit tobacco may contain potentially toxic organic impurities that result in a... more Counterfeit and illicit tobacco may contain potentially toxic organic impurities that result in adverse health effects to the consumer. The aim of this work was to investigate the feasibility of the identification of organic impurities in counterfeit or illicit tobacco using attenuated total reflectance- Fourier transform infrared (ATR-FT-IR) spectroscopy.
The identification of ‘legal highs’ is challenging as they often do not match their label claim a... more The identification of ‘legal highs’ is challenging as they often do not match their label claim and contain a wide range of impurities and/or adulterants. In addition, there is a need for techniques to be on-site, rapid and non-destructive. The feasibility of using the in-built algorithms of handheld near-infrared (NIR), Raman and attenuated total reflectance Fourier transform-infrared (ATR-FT-IR) spectroscopy for the identification of ‘legal high’ substances was investigated. Spectral libraries were constructed using three substances found in ‘legal highs’ (i.e., dextromethorphan, 2-aminoindane and lidocaine) and their 50:50 mixtures with caffeine. Model dilution mixtures with caffeine (i.e., 5 – 95% m/m) and seven ‘legal high’ Internet products were used to test the method. The ‘legal high’ constituents in most of the model mixtures were identified within a minimum range of 30 – 60% m/m for NIR, 20 – 75% m/m for Raman, and 41 – 85% m/m for ATR-FT-IR. This demonstrates that simple ...
Numbers of novel psychoactive substances (NPS) have been rapidly increasing over the past few yea... more Numbers of novel psychoactive substances (NPS) have been rapidly increasing over the past few years, with unprecedented challenges on traditional drug control systems. The web has been involved in the promotion and knowledge dissemination of NPS, which are being presented online as safer/legal alternatives to illicit drugs. The physical, psychological and social harms associated with NPS have been studied so far mainly in Europe and other English speaking countries. The aim of this research is to provide knowledge on the provision of NPS information/purchase opportunities to Middle East customers, whilst monitoring the Internet in Arabic and Farsi. Web analysis/assessments were carried out in both Farsi and Arabic between 2011 and 2013. Sources were scrutinized with the help of different search engines, including Google Arabic and Google Persian, to carry out searches focusing on both NPS retailers' and social network websites. The research identified 45 NPS apparently offered f...
Swift Quantification of Fenofibrate and Tiemonium methylsulfate Active Ingredients in Solid Drugs Using Particle Induced X-Ray Emission, Aug 2011
The quantification of active ingredients (AI) in drugs is a crucial and important step in the dru... more The quantification of active ingredients (AI) in drugs is a crucial and important step in the drug quality control process. This is usually performed by using wet chemical techniques like LC-MS, UV spectrophotometry and other appropriate organic analytical methods. However, if the active ingredient contains specific heteroatoms (F, S, Cl…), elemental IBA like PIXE and PIGE techniques, using small tandem accelerator of 1-2 MV, can be explored for molecular quantification. IBA techniques permit the analysis of the sample under solid form, without any laborious sample preparations. In this work, we demonstrate the ability of the Thick Target PIXE technique for rapid and accurate quantification of both low and high concentrations of active ingredients in different commercial drugs. Fenofibrate, a chlorinated active ingredient, is present in high amounts in two different commercial drugs, its quantification was done using the relative approach to an external standard. On the other hand, Tiemonium methylsulfate which exists in relatively low amount in commercial drugs, its quantification was done using GUPIX simulation code (absolute quantification) The experimental aspects related to the quantification validity (use of external standards, absolute quantification, matrix effect,...) are presented and discussed.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2006
The quantification of the active ingredient (AI) in drugs is a crucial and important step in the ... more The quantification of the active ingredient (AI) in drugs is a crucial and important step in the drug quality control process. This is usually performed by using wet chemical techniques like LC–MS, UV spectrophotometry and other appropriate organic analytical methods. In the case of an active ingredient contains specific heteroatoms (F, S, Cl, etc.,), elemental IBA technique can be explored for molecular quantification. IBA techniques permit the analysis of the sample under solid form, without any laborious sample preparation. This is an advantage when the number of sample is relatively large.In this work, we demonstrate the ability of the thick target PIXE (TT-PIXE) and the TT-PIGE techniques for rapid and accurate quantification of celecoxib in commercial drugs. The experimental aspects related to the quantification validity are presented and discussed.
Comparison of Laboratory and Handheld Raman Instruments for The Identification of Counterfeit Medicines, Jun 1, 2011
Raman spectroscopy offers a rapid, simple, and nondestructive technique for the identification of... more Raman spectroscopy offers a rapid, simple, and nondestructive technique for the identification of counterfeit medicines. The advantages of handheld Raman spectroscopy are that it is easy to use by unskilled personnel and it can identify a test pharmaceutical product on the spot, whether the product is in solid or liquid form. However, these instruments can operate only in reflection mode, and the Raman activity of a sample is often masked by fluorescent species in the sample, especially when the analysis is made in reflection mode. The objective of this work was to compare the use of a handheld and laboratory-based Raman instruments for authentication of pharmaceutical products obtained from the world market.
Spectrochimica Acta Part A-molecular and Biomolecular Spectroscopy, 2007
A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspiri... more A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspirin (ASP), paracetamol (PAR) and salicylic acid (SAL). The method is based on the use of the first and second derivatives of the ratio spectra and measurement at zero-crossing wavelengths. The ratio spectra were obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentration of the other components are then determined from their respective calibration curves treated similarly. The described method was applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.
Emergence and Identification of New Products of Designer Drug Products from the Internet, 2011
Designer drugs represent a rapidly expanding phenomenon particularly facilitated by their Interne... more Designer drugs represent a rapidly expanding phenomenon particularly facilitated by their Internet availability. These drugs are continuously emerging as analogues of controlled substances (amfetamine, aminoindane, cathinone, phencyclidine, etc...) and once an analogue has been banned; another replacement analogue appears on the market. They are often made in unlicensed laboratories which can result in their poor quality. This highlights the importance of analysing these products through detecting both their identity and purity. However, most of the analysis methods focused on emerging analogues of cathinone and very few studied other newer analogues such as phencyclidine derivatives. This is due partly to the regulations surrounding the analysis, the time consuming analytical procedures and the technical skills involved. Analysis of these designer drugs in the literature included both the identification of drug products and monitoring of products consistency over a period of time. In all cases, the results showed that these products may contain a range of a single or mixture of components including: a designer drug, a pharmaceutical active agent, an excipient or inorganic material.
This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent ... more This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent diffusion of its new derivative methoxetamine (“Special M”; MXE). The literature search on the nonclinical/recreational use of KET and MXE was carried out in a range of medical databases. Considering the limitations of peer-reviewed information, data were integrated with a qualitative assessment of a range of websites, drug fora, and other online resources including e-newsgroups, chat rooms, mailing lists, e-newsletters, and bulletin boards. The recreational use of KET has started since its discovery in 1962. This was due to its rapid onset, short duration of action, and peculiar psychotropic effects (“K-hole”). The latter effect ranges from confusion to dissociation and depersonalization (near-death experience). However, KET abuse is often associated with physical and psychological side effects, of which the worst is urological/bladder toxicity. Recently, MXE has emerged as a legal and “bladder-friendly” KET alternative. MXE presents with the same dissociative effect of KET, but with slower onset and longer duration of action. However, MXE seems to be associated with worse side effects than KET, ranging from mood disturbances/suicidal attempts to acute cerebellar toxicity. After 50 years of its discovery, KET has led to the emergence of MXE. However, this latter derivative does not appear to be a safer alternative to KET itself.This article reviews the recreational use of ketamine (“Special K”; KET) and explores the recent diffusion of its new derivative methoxetamine (“Special M”; MXE). The literature search on the nonclinical/recreational use of KET and MXE was carried out in a range of medical databases. Considering the limitations of peer-reviewed information, data were integrated with a qualitative assessment of a range of websites, drug fora, and other online resources including e-newsgroups, chat rooms, mailing lists, e-newsletters, and bulletin boards. The recreational use of KET has started since its discovery in 1962. This was due to its rapid onset, short duration of action, and peculiar psychotropic effects (“K-hole”). The latter effect ranges from confusion to dissociation and depersonalization (near-death experience). However, KET abuse is often associated with physical and psychological side effects, of which the worst is urological/bladder toxicity. Recently, MXE has emerged as a legal and “bladder-friendly” KET alternative. MXE presents with the same dissociative effect of KET, but with slower onset and longer duration of action. However, MXE seems to be associated with worse side effects than KET, ranging from mood disturbances/suicidal attempts to acute cerebellar toxicity. After 50 years of its discovery, KET has led to the emergence of MXE. However, this latter derivative does not appear to be a safer alternative to KET itself.
ABSTRACT Counterfeit medicines are a growing threat to public health across the world and screeni... more ABSTRACT Counterfeit medicines are a growing threat to public health across the world and screening methods are needed to allow their rapid identification. A counterfeiter must duplicate both the physical characteristics and the chemical content of a proprietary product to avoid it being detected as a counterfeit product and this is almost impossible to get right. Counterfeit proprietary medicines are, therefore, relatively easy to identify by near infrared (NIR) spectroscopy which can detect physical as well as chemical differences between products by simple spectral comparison. Identifying generic products is more difficult as they use different excipients in the tablet or capsule matrix. Nevertheless, using appropriate models and a large library, NIR spectroscopy can detect counterfeit generic versions. Detecting sub-standard proprietary medicines can be carried out with NIR spectroscopy models and the most widely used is partial least squares regression (PLSR). General rules for generating accurate quantitative models are easy to describe. Quantifying the active pharmaceutical ingredient (API) in generic products can also be carried out using PLSR models with calibration samples generated by manufacturing laboratory samples or by collecting many generic versions of a medicine so as to obtain a good range of the API content in tablets and capsules. Using hand-held instruments or mobile laboratories allows NIR spectrometers to be taken to places where analyses may be made quickly, rather than taking the samples to a laboratory. This has the enormous advantage that the screening of large numbers of samples may be made in pharmacies and wholesalers. Imaging can bring a whole new dimension to NIR spectroscopy to allow the identification of the API and individual excipients as well as measuring the particle sizes of components and giving a measure of the homogeneity of the matrix. The effect of water on potential misidentifications may be obviated by only using blister-packed samples, having large spectral libraries subjected to different humidities or omitting the spectral region where water absorbs.
Identification of Counterfeit Medicines from The Internet and the World Market Using Near-Infrared Spectroscopy, Aug 23, 2011
Pharmaceutical counterfeiting is a life threatening problem affecting all countries. Counterfeit ... more Pharmaceutical counterfeiting is a life threatening problem affecting all countries. Counterfeit medicines may be encountered anywhere in conventional markets or from the Internet. This paper proposes a rapid and non-destructive near-infrared spectroscopic method for the identification of counterfeit medicines using the minimum number of authentic samples. As little as twenty spectra from ten tablets from a batch are required to compare a test sample to its authentic counterpart. In this respect, tablets are measured as received and the correlation coefficient of the SNV-D2 spectra between the authentic sample and the test sample is determined. A correlation coefficient of lower than 0.95 indicates that the batch fails identification. In this case, if enough authentic samples are available, principal component analysis (PCA) could be applied. The PCA scores plot of the authentic and counterfeit samples with the 95% equal frequency ellipses drawn around the authentic sample set is effective in identifying counterfeits. The method could identify 82 known counterfeit medicines out of 201 medicines supplied from the Internet and the World market. However, it is still a comparative method to identify potential counterfeits and cannot identify products without authentic samples.
Identification of novel psychoactive substances (NPS) using hyphenated mass spectrometric techniques, Mar 1, 2012
The abuse of novel psychoactive substances (NPS) has been increasing over the last few years espe... more The abuse of novel psychoactive substances (NPS) has been increasing over the last few years especially as these products have become so readily available through the Internet. These products are emerging mostly as analogues or precursors of well-known drugs of abuse, such as amphetamine. However, a major problem that is more complicated than their abusive potential is that these products may not contain what is on the label. In fact, they have been shown to contain a mixture of drugs and excipients that may be toxic or even lethal. The number of deaths caused by NPS products has been increasing over the last year. This increase stimulates the need for sensitive techniques to identify these substances and detect any organic impurity in their products. Hyphenated mass spectrometric techniques, such as gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–mass spectrometry (LC–MS) offer some advantages. These techniques can both separate the constituents as well as confirm the chemical identity of the individual constituents in the product.
Laboratory versus handheld instruments: What you gain and what you loose, Aug 27, 2012
The objective of this work is to compare handheld to laboratory-based Raman instruments for the i... more The objective of this work is to compare handheld to laboratory-based Raman instruments for the identification of counterfeit medicines obtained from the world market. More than 200 tablets of proprietary and generic pharmaceutical products were obtained worldwide. Handheld Raman spectroscopy offered many advantages with respect to cost, rapidity, mobility, operation in wide temperature ranges, on-spot identification of materials and ease of use by non-skilled personnel. However, there were still many drawbacks associated with the use of handheld Raman instruments related to spectral quality, fluorescence and Raman activity. However, this did not affect the accuracy of identification.
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