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1.
Mikrochim Acta ; 191(9): 510, 2024 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103665

RESUMEN

Cocaine is one of the most abused illicit drugs, and its abuse damages the central nervous system and can even lead directly to death. Therefore, the development of simple, rapid and highly sensitive detection methods is crucial for the prevention and control of drug abuse, traffic accidents and crime. In this work, an electrochemical aptamer-based (EAB) sensor based on the low-temperature enhancement effect was developed for the direct determination of cocaine in bio-samples. The signal gain of the sensor at 10 °C was greatly improved compared to room temperature, owing to the improved affinity between the aptamer and the target. Additionally, the electroactive area of the gold electrode used to fabricate the EAB sensor was increased 20 times by a simple electrochemical roughening method. The porous electrode possesses more efficient electron transfer and better antifouling properties after roughening. These improvements enabled the sensor to achieve rapid detection of cocaine in complex bio-samples. The low detection limits (LOD) of cocaine in undiluted urine, 50% serum and 50% saliva were 70 nM, 30 nM and 10 nM, respectively, which are below the concentration threshold in drugged driving screening. The aptasensor was simple to construct and reusable, which offers potential for drugged driving screening in the real world.


Asunto(s)
Aptámeros de Nucleótidos , Cocaína , Técnicas Electroquímicas , Oro , Límite de Detección , Detección de Abuso de Sustancias , Cocaína/orina , Cocaína/análisis , Cocaína/sangre , Aptámeros de Nucleótidos/química , Humanos , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Oro/química , Detección de Abuso de Sustancias/métodos , Técnicas Biosensibles/métodos , Saliva/química , Electrodos , Conducción de Automóvil , Frío
2.
Am J Drug Alcohol Abuse ; 47(2): 247-254, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33481634

RESUMEN

Background: Between 1988 and 2013 the U.S. government conducted surveillance of national drug misuse use trends by collecting voluntary urine specimens from individuals under arrest in major counties. It was discontinued for financial reasons. The program was the only national survey that used a bioassay to measure drug use. Other national drug surveys continue to be based entirely on self-reports of drug use.Objective: Given the current opioid and incipient methamphetamine epidemics, this study aimed to demonstrate the feasibility of surveilling drugs subject to misuse among individuals under arrest using oral fluid collected anonymously by jail staff in one U.S. county. This method has never been previously employed with an offender population.Methods: The subjects were adults arrested for any reason and booked in one Midwest county jail in the U.S. between July 2019 - January 2020 (N = 196; 145 males). Oral fluid specimens were provided for research purposes voluntarily and anonymously.Results: 79% of individuals approached consented to participation. The most frequently detected drugs were cannabis (53%), methamphetamine (27%), cocaine (9%) and opioids (11%). Further, 74% tested positive for at least one drug; 36% tested positive for at least one illegal drug, 10% tested positive for at least one possibly illegal drug, and 54% tested positive for at least one legal drug (predominantly cannabis). (Tests for nicotine and ethanol were not included.)Conclusion: The feasibility of collecting oral fluid from individuals under arrest in a jail setting to measure the prevalence of drugs subject to misuse was demonstrated.


Asunto(s)
Criminales/estadística & datos numéricos , Drogas Ilícitas/análisis , Saliva/química , Detección de Abuso de Sustancias/métodos , Adolescente , Adulto , Analgésicos Opioides/análisis , Cannabis , Cocaína/análisis , Estudios de Factibilidad , Femenino , Humanos , Cárceles Locales/estadística & datos numéricos , Masculino , Metanfetamina/análisis , Michigan , Persona de Mediana Edad , Estados Unidos , Adulto Joven
3.
Mikrochim Acta ; 188(8): 279, 2021 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-34331135

RESUMEN

Molecularly imprinted polymers are efficient and selective adsorbents which act as artificial receptors for desired compounds with the ability to recognize the size, shape, and functional groups of the compounds simultaneously. A molecularly imprinted polymer is prepared by the polymerization of functional monomers around a template (analyte) molecule. Afterward, the removal of the template from the polymer matrix leaves a selective cavity behind. The fabrication and development of molecularly imprinted polymers grew rapidly, due to their low cost, simple preparation, selectivity, sensitivity, and stable physicochemical properties. Traditionally, molecularly imprinted polymers can be synthesized using two main methods, namely bulk and surface imprinting. For more efficient use of the latter method, researchers have developed molecularly imprinted polymers grafted on the solid-phase matrix (substrate). This grafting technique would be particularly useful for surface imprinting of macromolecules, such as proteins. Cellulose fibers of papers with unique properties such as being abundant, retaining a porous structure, having good adsorption properties, and possessing hydroxyl groups naturally have gained much attention as substrate. The goal of this review is to introduce molecularly imprinted polymer-grafted or molecularly imprinted polymer-coated paper, as an interesting, simple, and efficient method in the detection and separation of small and large molecules. Therefore, in the present paper, several recent preparation techniques and applications of molecularly imprinted polymer-grafted paper are reviewed and discussed in detail. Green, cost-effective, selective, and sensitive paper-based sensor prepared via grafting molecularly imprinted polymer on paper surface with the potential use for online detection trace of analytes in the point-of-care testing.


Asunto(s)
Celulosa/química , Cocaína/análisis , Colorantes Fluorescentes/química , Metanfetamina/análisis , Polímeros Impresos Molecularmente/química , Adsorción , Técnicas Biosensibles , Hidróxidos/química , Límite de Detección , Metales/química , Metacrilatos/química , Impresión Molecular , Nanoestructuras/química , Nanotubos de Carbono/química , Papel , Polimerizacion , Porosidad , Puntos Cuánticos/química , Dióxido de Silicio/química , Espectrometría de Fluorescencia , Propiedades de Superficie
4.
Analyst ; 144(15): 4639-4646, 2019 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-31250860

RESUMEN

A selective electrochemical sensor for direct detection of cocaine was developed based on molecularly imprinted polymers electropolymerized onto graphene-modified electrodes. Palladium nanoparticles were integrated in the sensing layer for the benefit of enhancing the communication between the imprinted sites and the electrode and improving their homogeneous distribution. The molecularly imprinted polymer was synthesized by cyclic voltammetry using p-aminobenzoic acid as a high affinity monomer selected by computational modeling, and cocaine as a template molecule. Experimental parameters related to the electrochemical deposition of palladium nanoparticles, pH, composition of the electropolymerization mixture, extraction and rebinding conditions were studied and optimized. Under optimized conditions, the oxidation peak current varied linearly with cocaine concentration in the range of 100-500 µM, with a detection limit of 50 µM (RSD 0.71%, n = 3). The molecularly imprinted sensor was able to detect cocaine in saliva and river water with good recoveries after sample pretreatment and was successfully applied for screening real street samples for cocaine.


Asunto(s)
Materiales Biomiméticos/química , Cocaína/análisis , Polímeros/química , Ácido 4-Aminobenzoico/química , Materiales Biomiméticos/síntesis química , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Galvanoplastia , Grafito/química , Drogas Ilícitas/análisis , Ligandos , Límite de Detección , Nanopartículas del Metal/química , Impresión Molecular , Paladio/química , Polimerizacion , Polímeros/síntesis química , Ríos/química , Saliva/química , Contaminantes Químicos del Agua/química
5.
Clin Chem ; 63(11): 1745-1752, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28939761

RESUMEN

BACKGROUND: Paper spray mass spectrometry (PS-MS) is a technique that has recently emerged and has shown excellent analytical sensitivity to a number of drugs in blood. As an alternative to blood, fingerprints have been shown to provide a noninvasive and traceable sampling matrix. Our goal was to validate the use of fingerprint samples to detect cocaine use. METHODS: Samples were collected on triangular pieces (168 mm2) of washed Whatman Grade I chromatography paper. Following application of internal standard, spray solvent and a voltage were applied to the paper before mass spectrometry detection. A fingerprint visualization step was incorporated into the analysis procedure by addition of silver nitrate solution and exposing the sample to ultraviolet light. RESULTS: Limits of detection for cocaine, benzoylecgonine, and methylecgonine were 1, 2, and 31 ng/mL respectively, with relative standard deviations < 33%. No matrix effects were observed. Analysis of 239 fingerprint samples yielded a 99% true-positive rate and a 2.5% false-positive rate, based on the detection of cocaine, benzoylecgonine, or methylecgonine with use of a single fingerprint. CONCLUSIONS: The method offers a qualitative and noninvasive screening test for cocaine use. The analysis method developed is rapid (4 min/sample) and requires no sample preparation.


Asunto(s)
Cocaína/análogos & derivados , Cocaína/análisis , Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos , Dermatoglifia , Humanos , Límite de Detección , Papel , Saliva/química , Sudor/química
6.
Anal Chem ; 88(3): 1506-10, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26750765

RESUMEN

Nanomaterials which can respond to external stimuli have attracted considerable attention due to their potential applications in sensing and biomedicine. One of the most promising classes of such materials is the stimuli-responsive liposome that can release its contents in response to a specific target. Despite recent progress, development of liposomes responsive to small molecular targets remains a challenge, due to the difficulty in designing the transduction process to link between target binding and triggered release, even though small molecular metabolites play important roles in many biological processes. Herein, we demonstrate a combination of an aptamer (apt) for target recognition and enzyme phosphatidylcholine 2-acetylhydrolase (PLA2) for rupture of liposome. As a proof-of-concept, cocaine molecules were used to trigger the release of the enzyme. The exposure to DNA-PLA2 conjugates induced the rupture of liposome containing uranin and gadopentetic acid (Gd-DTPA), allowing multimodal fluorescent and MRI detection of cocaine. The strategy demonstrated in this work can be generally applied to other imaging modalities by loading different imaging agents, as well as other targets by using different functional DNAs.


Asunto(s)
Aptámeros de Nucleótidos/química , Cocaína/análisis , ADN/química , Liposomas/química , Fosfolipasas A2/química , Estructura Molecular , Fosfolipasas A2/metabolismo
7.
Anal Chem ; 88(2): 1259-65, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26648347

RESUMEN

In recent years, different geometrical configurations of solid-phase microextraction (SPME) have been directly coupled to mass spectrometry, resulting in benefits such as diminishing matrix effects, improvement of detection limits, and considerable enhancement of analysis throughput. Although SPME fibers have been used for years, their potential for quantitative analysis when directly combined with mass spectrometry has not been explored to its full extent. In this study, we present the direct coupling of biocompatible SPME (Bio-SPME) fibers to mass spectrometry via nanoelectrospray ionization (nano-ESI) emitters as a powerful tool for fast quantitative analysis of target analytes in biofluids. Total sample preparation time does not exceed 2 min, and by selecting an appropriate fiber length and sample vessel, sample volumes ranging between 10 and 1500 µL can be used. Despite the short extraction time of the technique, limits of detection in the subnanogram per milliliter with good accuracy (≥90%) and linearity (R(2) > 0.999) were attained for all the studied probes in phosphate-buffered saline (PBS), urine, and whole blood. Given that Bio-SPME-nano-ESI efficiently integrates sampling with analyte extraction/enrichment, sample cleanup (including elimination of matrix effects in the form of particles), and ionization, our results demonstrated that it is an advantageous configuration for bioanalytical applications such as therapeutic drug monitoring, doping in sports, and pharmacological studies in various matrixes.


Asunto(s)
Amitriptilina/sangre , Cocaína/análisis , Codeína/orina , Metadona/orina , Nanotecnología , Microextracción en Fase Sólida , Materiales Biocompatibles/química , Femenino , Voluntarios Sanos , Humanos , Masculino , Nanotecnología/instrumentación , Microextracción en Fase Sólida/instrumentación , Espectrometría de Masa por Ionización de Electrospray/instrumentación
8.
Chemistry ; 22(38): 13488-95, 2016 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-27505065

RESUMEN

We present herein a novel combination of gated mesoporous silica nanoparticles (MSNs) and surface-enhanced Raman scattering (SERS) for sensing applications. As a proof-of-concept, we show the design of a system comprising MSNs loaded with crystal violet (CV), a molecule with high Raman cross section acting as SERS reporter, and capped with either a suitable DNA sequence for the detection of Mycoplasma genomic DNA or with an aptamer that selectively coordinates cocaine. In both cases the presence of the corresponding target analyte in solution (i.e., genomic DNA or cocaine) resulted in the release of CV. CV delivery was detected by SERS upon adsorption on gold nanotriangles (AuNTs), which display an efficient electromagnetic field enhancement and a high colloidal stability. By using this novel procedure a limit of detection of at least 30 copies DNA per µL was determined for the detection of Mycoplasma genomic DNA, whereas cocaine was detected at concentrations as low as 10 nm.


Asunto(s)
Cocaína/análisis , Mycoplasma/aislamiento & purificación , Nanoestructuras/química , Adsorción , Aptámeros de Nucleótidos/química , Técnicas Biosensibles , ADN Bacteriano/análisis , Oro/química , Mycoplasma/genética , Tamaño de la Partícula , Polietilenglicoles/química , Porosidad , Dióxido de Silicio/química , Espectrometría Raman , Propiedades de Superficie
9.
Anal Chem ; 87(3): 1896-902, 2015 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-25540088

RESUMEN

On-site oral fluid testing for drugs of abuse has become prominent in order to take immediate administrative action in an enforcement process. Herein, we report a DVD technology-based indirect competitive immunoassay platform for the quantitative detection of drugs of abuse. A microfluidic approach was adapted to prepare multiplex immunoassays on a standard DVD-R, an unmodified multimode DVD/Blu-Ray drive to read signal, and a free disc-quality analysis software program to process the data. The DVD assay platform was successfully demonstrated for the simultaneous, quantitative detection of drug candidates (morphine and cocaine) in oral fluids with high selectivity. The detection limit achieved was as low as 1.0 ppb for morphine and 5.0 ppb for cocaine, comparable with that of standard mass spectrometry and ELISA methods.


Asunto(s)
Cocaína/análisis , Inhibidores de Captación de Dopamina/análisis , Inmunoensayo/instrumentación , Morfina/análisis , Narcóticos/análisis , Saliva/química , Detección de Abuso de Sustancias/instrumentación , Diseño de Equipo , Humanos , Drogas Ilícitas/análisis , Límite de Detección , Técnicas Analíticas Microfluídicas/instrumentación
10.
Anal Chem ; 87(8): 4275-82, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25806667

RESUMEN

A versatile point-of-care assay platform was developed for simultaneous detection of multiple targets based on a microfluidic paper-based analytic device (µPAD) using a target-responsive hydrogel to mediate fluidic flow and signal readout. An aptamer-cross-linked hydrogel was used as a target-responsive flow regulator in the µPAD. In the absence of a target, the hydrogel is formed in the flow channel, stopping the flow in the µPAD and preventing the colored indicator from traveling to the final observation spot, thus yielding a "signal off" readout. In contrast, in the presence of a target, no hydrogel is formed because of the preferential interaction of target and aptamer. This allows free fluidic flow in the µPAD, carrying the indicator to the observation spot and producing a "signal on" readout. The device is inexpensive to fabricate, easy to use, and disposable after detection. Testing results can be obtained within 6 min by the naked eye via a simple loading operation without the need for any auxiliary equipment. Multiple targets, including cocaine, adenosine, and Pb(2+), can be detected simultaneously, even in complex biological matrices such as urine. The reported method offers simple, low cost, rapid, user-friendly, point-of-care testing, which will be useful in many applications.


Asunto(s)
Adenosina/análisis , Cocaína/análisis , ADN/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Plomo/análisis , Técnicas Analíticas Microfluídicas , Papel , ADN/síntesis química , ADN/aislamiento & purificación , Hidrogel de Polietilenoglicol-Dimetacrilato/síntesis química , Hidrogel de Polietilenoglicol-Dimetacrilato/aislamiento & purificación , Estructura Molecular , Compuestos Organofosforados/síntesis química , Compuestos Organofosforados/química , Sistemas de Atención de Punto
11.
Forensic Sci Int ; 355: 111929, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38262308

RESUMEN

BACKGROUND: Drug driving represents a public safety concern, and the size of this issue in Italy is not fully known. Drug testing is composed of two steps: 1) screening and 2) confirmatory analysis. The second step, and the associate medical examination to assess the state of impairment, usually are not performed right after the screening as they require specialized personnel and instrumental equipment that are not historically available at roadblocks. These pitfalls make this process both complicated and time-consuming. METHODS: A mobile laboratory was set up in 2019 by the Forensic Lab Service S.r.l. (limited liability company) to improve roadblock timing, planning, as well as to shed light on the extent of the drug driving issue in Italy. Drug screenings were performed using DrugWipe® Saliva testing. Confirmatory analysis was performed on oral fluids by liquid chromatography coupled with tandem mass spectrometry. A dedicated room of the mobile laboratory was also designed for drug driving medical assessment. RESULT: 2082 samples were collected during 88 road safety services held in different locations across Italy. In total, 9 % of the tested subjects were positive to both the screening and the confirmatory analysis. The most prevalent illicit drugs found in this study were THC (72 %), followed by cocaine (41 %). Drug drivers were mostly male (93 %) and younger than 30 years of age (58 %). CONCLUSIONS: The prevalence of drivers testing positive for illicit drugs resulted to be higher compared to the results obtained in the DRUID project and to other surveys previously performed in Italy. These data demonstrate the need for control services to improve road safety in regards to drug driving.


Asunto(s)
Conducción de Automóvil , Cocaína , Drogas Ilícitas , Humanos , Masculino , Femenino , Drogas Ilícitas/análisis , Detección de Abuso de Sustancias/métodos , Espectrometría de Masas en Tándem , Cocaína/análisis , Italia , Saliva/química
12.
J Anal Toxicol ; 48(5): 388-392, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38155345

RESUMEN

Coca tea is a popular drink in some countries of South America, where it is presented as a safe energy preparation, based on a limited total content of cocaine of ∼3-5 mg. Tea bags can be bought with no legal considerations in these countries both by locals and tourists, but its consumption can have consequences when consumed overseas. Driving under the influence of cocaine is banned in most of the places in the world and can be documented by oral fluid testing. A study was implemented with coca tea bags (Coca & Muna) purchased in Peru, after a French attorney-at-law contacted the laboratory to assess the involvement of coca tea in the positive oral fluid results of a driver. Ten healthy volunteers consumed 250 mL of coca tea containing 4.5 mg of cocaine. No volunteer reported any change in behavioral effects after consumption of the coca tea. Oral fluid was collected with a swab (FloqSwab™, Copan) over 8 h to follow the elimination of cocaine and its major metabolites (benzoylecgonine and ecgonine methylester). This is the procedure used by the French police. All samples were analyzed by UHPLC-MS-MS after Quantisal™ buffer desorption. As the device does not allow measurement of the amount of collected fluid, the results are qualitative. This is in accordance with the French law that requires a yes or no response about the presence of cocaine, with a minimum required performance level of 10 ng/mL of cocaine or benzoylecgonine. Parent cocaine was identified for 30-120 min. Benzoylecgonine and ecgonine methylester were identified between 1 and 8 h, with a large inter-individual variation. Although it is generally accepted that a 4-5 mg cocaine dose has no significant pharmacological effect, the consumption of coca tea can lead to the suspension of a person's driving license due to a positive oral fluid test.


Asunto(s)
Cocaína , Saliva , Detección de Abuso de Sustancias , Humanos , Cocaína/análisis , Cocaína/análogos & derivados , Saliva/química , Detección de Abuso de Sustancias/métodos , Coca , Espectrometría de Masas en Tándem , Alcaloides/análisis , Cromatografía Líquida de Alta Presión , Conducción de Automóvil/legislación & jurisprudencia , Adulto , Masculino
13.
Forensic Sci Int ; 363: 112185, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39151241

RESUMEN

BACKGROUND: Post-mortem toxicology constantly deals with the research of reliable alternative matrices to be applied in case of highly damaged corpses (such us carbonized, skeletonized, human remains, etc.). Teeth represent a promising alternative matrix since dental tissues are endowed by different features, resistance and stability after death. SCOPE: Since scant literature reported on the pharmacokinetics and mechanism of incorporation of xenobiotics into dental tissues, this pilot research aims to investigate whether in the pulp can be detected the same substances found in blood in drug related death cases. Secondly, the study is addressed to disclose the possible deposit of drugs in dental hard tissues (dentine and/or enamel), thus contributing to reconstruct the drug abuse history (timing, e.g.). MATERIALS AND METHODS: The study experimented with a novel method to separately analyse dental enamel, dentin, and pulp, applied to 10 teeth collected during autopsies of drug-related deaths along with blood and hair samples for classic toxicological analyses. Each tooth was prepared by "pulverization technique" and then analysed by gas chromatography paired with mass spectrometry (GC-MS) and ultra high performance liquid chromatography coupled to high resolution mass spectrometry (UHPLC/HR-MS) for searching cocaine, opiates, and metabolites. The results were then compared with those obtained from blood and hair samples. RESULTS: Preliminary results demonstrated that teeth differ from any other classic matrix (blood and hairs) since the qualitative correspondence of the detected substances between pulp and blood as well as dental hard tissues and hair suggests that they can be useful in post-mortem evaluation as a unique matrix for both acute and chronic assumptions of drugs. The mechanism of accumulation of substances in mineralized dental tissues emerged the most significant result, being influenced by the type of molecule and the method of assumption. The main limitation of this study is the limited availability of the sample and the absence of anamnestic information of the time, rates and method of drug assumption during life. Further research is necessary to systematically investigate the distribution of different substances within the different tissues of the tooth.


Asunto(s)
Esmalte Dental , Pulpa Dental , Dentina , Toxicología Forense , Cromatografía de Gases y Espectrometría de Masas , Detección de Abuso de Sustancias , Trastornos Relacionados con Sustancias , Humanos , Proyectos Piloto , Esmalte Dental/química , Dentina/química , Pulpa Dental/química , Pulpa Dental/patología , Detección de Abuso de Sustancias/métodos , Masculino , Adulto , Femenino , Toxicología Forense/métodos , Cabello/química , Persona de Mediana Edad , Narcóticos/análisis , Cocaína/análisis , Adulto Joven , Cromatografía Líquida de Alta Presión , Analgésicos Opioides/análisis , Espectrometría de Masas
14.
Forensic Sci Int ; 361: 112132, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38981416

RESUMEN

Due to the restricted nature of illicit drugs, it is difficult to conduct research surrounding the analysis of this drug material for any potential DNA in sufficient quantities acceptable for high numbers of replicates. Therefore, the current research available in peer reviewed journals thus far regarding analysing illicit drugs for DNA has been performed under varying experimental conditions, often using surrogate chemicals in place of illicit drugs. The data presented within this study originated from the analysis of genuine illicit drugs prepared both in controlled environments and those seized at the Australian border (and therefore from an uncontrolled environment) to determine if DNA can be obtained from this type of material. This study has been separated into three main parts (total n=114 samples): firstly, methamphetamine synthesised within a controlled environment was spiked with both saliva and trace DNA to determine the yield following DNA extraction; secondly, methamphetamine also synthesised in a controlled environment but on a larger scale was tested for the amount of DNA added incidentally throughout the synthesis, including the additional steps of recrystallising, homogenising and "cutting" the drug material to simulate preparation for distribution; and thirdly, the detection of human DNA within samples of cocaine and heroin seized at the Australian border. The DNA Fast Flow Microcon Device was utilised to concentrate all replicates from the same source into one combined extract to improve the DNA profiles for the samples where no DNA spiking occurred. Full STR profiles were successfully obtained from drug samples spiked with both saliva and trace DNA. Methamphetamine was present in the final DNA extracts and caused incompatibilities with the quantification of DNA using Qubit. The yields of DNA from drugs not spiked with DNA sources were much lower, resulting in 36 % of samples yielding alleles where all others did not. These results were not unexpected given these were realistic drug samples where the history of the drug material was unknown. This is the first study to obtain DNA profiles from genuine illicit drug material in both controlled and uncontrolled environments and indicates that the analysis of illicit drugs for DNA is an avenue worth pursuing to provide information which can in turn assist with disrupting the supply of these drugs. Given that DNA profiling is carried out worldwide using essentially the same systems as described within this study, the potential for impact is on a national and international scale.


Asunto(s)
Dermatoglifia del ADN , ADN , Drogas Ilícitas , Saliva , Humanos , Drogas Ilícitas/análisis , Drogas Ilícitas/química , ADN/análisis , Saliva/química , Metanfetamina/análisis , Heroína/análisis , Heroína/química , Australia , Repeticiones de Microsatélite , Cocaína/análisis , Cocaína/química , Reacción en Cadena de la Polimerasa
15.
J Am Chem Soc ; 135(10): 3748-51, 2013 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-23339662

RESUMEN

Portable devices with the advantages of rapid, on-site, user-friendly, and cost-effective assessment are widely applied in daily life. However, only a limited number of quantitative portable devices are commercially available, among which the personal glucose meter (PGM) is the most successful example and has been the most widely used. However, PGMs can detect only blood glucose as the unique target. Here we describe a novel design that combines a glucoamylase-trapped aptamer-cross-linked hydrogel with a PGM for portable and quantitative detection of non-glucose targets. Upon target introduction, the hydrogel collapses to release glucoamylase, which catalyzes the hydrolysis of amylose to produce a large amount of glucose for quantitative readout by the PGM. With the advantages of low cost, rapidity, portability, and ease of use, the method reported here has the potential to be used by the public for portable and quantitative detection of a wide range of non-glucose targets.


Asunto(s)
Adenosina Trifosfato/análisis , Aptámeros de Nucleótidos/química , Automonitorización de la Glucosa Sanguínea , Cocaína/análisis , Hidrogel de Polietilenoglicol-Dimetacrilato/química , alfa-Glucosidasas/química , Adenosina Trifosfato/metabolismo , Amilosa/química , Amilosa/metabolismo , Aptámeros de Nucleótidos/metabolismo , Biocatálisis , Cocaína/metabolismo , Glucosa/análisis , Glucosa/biosíntesis , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/metabolismo , Hidrólisis , alfa-Glucosidasas/metabolismo
16.
Anal Chem ; 85(15): 7558-65, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23815182

RESUMEN

We present a portable microsystem to quantitatively detect cocaine in human saliva. In this system, we combine a microfluidic-based multiphase liquid-liquid extraction method to transfer cocaine continuously from IR-light-absorbing saliva to an IR-transparent solvent (tetrachloroethylene) with waveguide IR spectroscopy (QC-laser, waveguide, detector) to detect the cocaine on-chip. For the fabrication of the low-cost polymer microfluidic chips a simple rapid prototyping technique based on Scotch-tape masters was further developed and applied. To perform the droplet-based liquid-liquid extraction, we designed and integrated a simple and robust droplet generation method based on the capillary focusing effect within the device. Compared to well-characterized and commonly used microfluidic H-filters, our system showed at least two times higher extraction efficiencies with potential for further improvements. The current liquid-liquid extraction method alone can efficiently extract cocaine and pre-concentrate the analytes in a new solvent. Our fully integrated optofluidic system successfully detected cocaine in real saliva samples spiked with the drug (500 µg/mL) and allowed real time measurements, which makes this approach suitable for point-of-care applications.


Asunto(s)
Cocaína/análisis , Cocaína/aislamiento & purificación , Extracción Líquido-Líquido/métodos , Técnicas Analíticas Microfluídicas/métodos , Saliva/química , Espectrofotometría Infrarroja/métodos , Métodos Analíticos de la Preparación de la Muestra , Cocaína/química , Humanos
17.
Proc Natl Acad Sci U S A ; 107(24): 10837-41, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20534499

RESUMEN

We have demonstrated a novel sensing strategy employing single-stranded probe DNA, unmodified gold nanoparticles, and a positively charged, water-soluble conjugated polyelectrolyte to detect a broad range of targets including nucleic acid (DNA) sequences, proteins, small molecules, and inorganic ions. This nearly "universal" biosensor approach is based on the observation that, while the conjugated polyelectrolyte specifically inhibits the ability of single-stranded DNA to prevent the aggregation of gold-nanoparticles, no such inhibition is observed with double-stranded or otherwise "folded" DNA structures. Colorimetric assays employing this mechanism for the detection of hybridization are sensitive and convenient--picomolar concentrations of target DNA are readily detected with the naked eye, and the sensor works even when challenged with complex sample matrices such as blood serum. Likewise, by employing the binding-induced folding or association of aptamers we have generalized the approach to the specific and convenient detection of proteins, small molecules, and inorganic ions. Finally, this new biosensor approach is quite straightforward and can be completed in minutes without significant equipment or training overhead.


Asunto(s)
Colorimetría/métodos , ADN/análisis , Nanopartículas del Metal , Proteínas/análisis , Técnicas Biosensibles/métodos , Cocaína/análisis , Fluorenos , Oro , Humanos , Iones/análisis , Polímeros , Compuestos de Amonio Cuaternario
18.
Med Leg J ; 81(Pt 3): 135-43, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24057314

RESUMEN

In recent years, the interest in oral fluid as a biological matrix has significantly increased, particularly for detecting driving under the influence of drugs. In this study, the concentration of cocaine and its relationship with clinical symptoms in drivers suspected of driving under the influence of drugs was evaluated. A total of 154 samples of oral fluid, which tested positive for cocaine in previous immunoassay screening, Cozart Drug Detector System, were confirmed using gas chromatography/mass spectrometry method. In Catalonia, during 2007-2010, there were 1791 samples positive for cocaine among a total of 3468 samples taken from drivers who tested positive for any drug of abuse. The evaluation of clinical symptoms was through a questionnaire that was filled in by the police officers who collected the samples. The mean concentration of cocaine was 4.11 mg/l and median concentration was 0.38 mg/l (range 0.01-345.64 mg/l). Clinical impairment symptoms such as motor coordination, walking, speech, mood and state of pupils were not significant. The testing of oral fluids presents fewer ethical problems than blood or urine.


Asunto(s)
Conducción de Automóvil/legislación & jurisprudencia , Cocaína/análisis , Narcóticos/análisis , Saliva/química , Trastornos Relacionados con Sustancias/diagnóstico , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , España , Detección de Abuso de Sustancias
19.
Drug Alcohol Depend ; 250: 110894, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37481872

RESUMEN

BACKGROUND: The aims are to compare the results of presumptive drug testing with confirmation of positives vs. direct-to-definitive drug testing, combined with investigation of urine vs. oral fluid as test matrices. METHODS: Paired oral fluid and urine specimens were collected voluntarily and anonymously from 1098 individuals applying for methadone treatment in 11 clinics across 7 U.S. states. All specimens were analyzed by immunoassay (IA) and liquid chromatography-tandem mass spectrometry (LC-MS-MS). RESULTS: Confirmed IA prevalences for urine were significantly higher than for oral fluid for 7 out of 10 drug classes - benzodiazepines, cannabis, cocaine, methadone, opiates, oxycodone and tramadol. Drug prevalences by direct-to-definitive LC-MS-MS were either the same or higher than prevalences by confirmed IA. Drug prevalences by LC-MS-MS were higher in urine for two drug classes (cocaine, methadone) and higher in oral fluid for two drug classes (buprenorphine, tramadol), but were equivalent in urine and oral fluid when averaged over all 10 drug classes. Certain drugs of special concern such as heroin and buprenorphine were more frequently detected in oral fluid than urine. CONCLUSIONS: Urine analysis showed some technical advantage over oral fluid in sensitivity to several drug classes within a confirmed IA testing protocol, but this may be outweighed if there is reason to believe that tampering with urine specimens is a significant problem. Overall drug detection by direct-to-definitive testing was similar for oral fluid and urine, but one matrix may be preferable if there is a particular drug of clinical or epidemiological interest.


Asunto(s)
Buprenorfina , Cocaína , Drogas Ilícitas , Tramadol , Humanos , Drogas Ilícitas/análisis , Saliva/química , Detección de Abuso de Sustancias/métodos , Buprenorfina/análisis , Metadona/análisis , Cocaína/análisis
20.
Forensic Sci Int ; 352: 111835, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37748427

RESUMEN

BACKGROUND: Driving under the influence of drugs (DUID) is a risk factor for traffic accidents. The testing of oral fluid by roadside immunochromatography and laboratory-confirmed chromatography coupled to mass spectrometry (LC-MS/MS) analysis to detect drug abuse has increased in France. The aim of this study was to describe the trends observed in drivers testing positive for illicit drugs in oral fluid and to investigate the concordance between the two analytical methods used. METHODS: We received for confirmation 3051 oral fluid samples from drivers who had tested positive at the roadside with a Drugwipe-5S® device between 2018 and 2021 around Grenoble, France. Samples were collected with FLOQSwab® and analyzed by LC-MS/MS (THC, amphetamine, methamphetamine, MDMA and MDA, MDEA, cocaine and benzoylecgonine, morphine and 6-monoacetylmorphine) at Grenoble Alpes University Hospital, France. Binomial logistic regression was performed to evaluate consumption trends. RESULTS: Most of the drivers were men (93.2%), with a median age of 26 years (range: 14-66 years). Cannabis (94.6%) cocaine (17.5%) and MDMA (2.5%) were the drugs most frequently detected. Poly-drug use was observed in 17.3% of drivers and involved cannabis and cocaine in 85.3% of these drivers. Poly-drug use was more frequent among drivers over the age of 32 years (OR, 3.48; 95% CI, 2.59-4.68; p ≤ .001), as was cocaine use (OR, 5.15; 95% CI, 3.75-7.08; p ≤ .001). The frequency of positive tests for amphetamines was higher in women than in men (OR, 2.53; 95% CI, 1.50-4.27; p ≤ .001). The positive predictive value of Drugwipe-5S was 98.2% for cannabis, 22.6% for amphetamines, 75.4% for cocaine and 17.3% for opiates. At least one discrepancy between Drugwipe-5S® and LC-MS/MS results was observed for 22.3% of the samples tested. CONCLUSION: We report recent trends for drivers testing positive for illicit drugs in oral fluid in France. Cannabis was the most prevalent drug of abuse identified, suggesting that a general prevention program might be useful. Our results also highlight the need for LC-MS/MS confirmation when screening oral fluid for drugs of abuse.


Asunto(s)
Conducción de Automóvil , Cocaína , Alucinógenos , Drogas Ilícitas , N-Metil-3,4-metilenodioxianfetamina , Trastornos Relacionados con Sustancias , Masculino , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Cromatografía Liquida , N-Metil-3,4-metilenodioxianfetamina/análisis , Espectrometría de Masas en Tándem , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/epidemiología , Drogas Ilícitas/análisis , Cocaína/análisis , Alucinógenos/análisis , Anfetamina/análisis , Agonistas de Receptores de Cannabinoides/análisis , Detección de Abuso de Sustancias/métodos , Saliva/química
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