Analysis of unknown (unlabeled/mislabeled) drug products for active pharmaceutical ingredients and related substances by an international mail facility satellite laboratory equipped with rapid screening devices.

Two chemists employed a three-device rapid screening "toolkit" consisting of a handheld Raman spectrometer, transportable mass spectrometer, and portable Fourier transform infrared (FT-IR) spectrometer at an international mail facility (IMF) satellite laboratory to examine unknown (unlabeled/mislabeled) products for the presence of active pharmaceutical ingredients (APIs). Phase I of this project previously demonstrated that this toolkit was the most effective collection of instruments for identifying APIs in product types collected at IMFs during a nationwide mail blitz and Phase II of this project previously demonstrated that results generated using the toolkit during a satellite laboratory pilot program were as reliable as those generated by a full-service library when two or more of these instruments identify an API. This study (Phase III) described the results of the satellite laboratory toolkit during production mode and encompassed the period ranging from June 2021 through December 2022. During this study, a total of 858 products were examined on-site at the IMF. The satellite laboratory yielded conclusive results for 726 (84.6%) products, which were used to support regulatory action, and identified 132 (15.4%) products that required additional full-service laboratory analyses due to inconclusive results. The satellite and full-service laboratory verified/confirmed at least one API/related substance in 617 (71.9%) products. A total of 709 APIs/related substances were found in the 617 products, and 202 of these 709 compounds were unique/different. Overall, during Phases I through III of this program, 350 different substances have been identified in products collected at IMFs.

Rapid screening of 2-benzylbenzimidazole nitazene analogs in suspect counterfeit tablets using Raman, SERS, DART-TD-MS, and FT-IR.

Developing methods to rapidly screen for novel synthetic 2-benzylbenzimidazole opioids, also known as nitazenes, has become increasingly important due to their high potency. These compounds have potency comparable or exceeding that of fentanyl by up to 10 times and have been implicated in approximately 5% of all drug overdose deaths in the United States in 2021. This paper details the authenticity determination of suspect tablets and the identification of three nitazene analogs (N-pyrrolidino etonitazene, isotonitazene, and etodesnitazene) in suspect tablets seized at a mail facility using Raman and surface-enhanced Raman scattering (SERS) with handheld devices, portable Fourier transform infrared spectrometer (FT-IR), and a direct analysis in real-time ambient ionization coupled to a thermal desorption unit and a mass spectrometer (DART-TD-MS). These methods are rapid and excellent for screening opioids in suspect tablets but could not fully determine the exact structure of some of the nitazene analogs present due to spectral similarities or similar fragmentation patterns. Liquid chromatography-mass spectrometry (LC-MS) confirmed the presence of these nitazene compounds in addition to other opioids/drugs that were in trace quantities. The quantitative high-performance liquid chromatography coupled with ultraviolet (HPLC-UV) detection experiments determined that the suspect tablets contained an average of 0.817 mg of N-pyrrolidino etonitazene per tablet. The results obtained reveal that the simultaneous deployment of these complementary and orthogonal portable analytical techniques as part of a workflow allows suspect tablets to be screened and nitazene-type drugs to be identified in suspect counterfeit tablets at remote sampling sites.

Rapid detection of active pharmaceutical ingredients in drug products collected at an international mail facility by a satellite laboratory using a "toolkit" consisting of a handheld Raman spectrometer, portable mass spectrometer and portable FT-IR spectrometer.

A satellite laboratory "toolkit" consisting of a handheld Raman spectrometer, portable direct analysis in real-time mass spectrometer (DART-MS) and portable Fourier transform infrared (FT-IR) spectrometer was employed to examine 926 pharmaceutical, unknown and dietary supplement products collected at an international mail facility (IMF) for the presence of declared and undeclared active pharmaceutical ingredients (APIs) over the course of 68 working days. The toolkit successfully identified over 650 APIs, including over 200 unique APIs, using two or more devices. The performance of each individual device, and toolkit as a whole, were evaluated on all products and a subset of the products was forwarded to full-service laboratories for confirmatory analysis to determine false positive and false negative rates of the toolkit. The subset consisted of seven negative items (those not found to contain APIs using the toolkit) and 124 positive items (those found to contain at least one API using the toolkit). Overall, no false positives were detected in the negative items and only four false negatives and five false positives were detected in the positive items. Regarding the positive items, 119 of the 124 items were found to contain at least one API using at least two toolkit devices; each of these APIs were confirmed by a full-service laboratory. Furthermore, 90.2% of the APIs found by confirmatory laboratory analysis were detected by at least two toolkit devices. Based on these metrics and the fact that no false positives were detected by more than one device, it was concluded that when the toolkit detects and subsequently verifies/confirms an API using two or more devices, the results are as reliable as those generated by a full-service laboratory.

Screening suspect pharmaceuticals for illicit designer benzodiazepines using raman, SERS, and FT-IR prior to comprehensive analysis using LC-MS.

The emergence of illicit designer benzodiazepines with high dependency and no approved clinical use are of great US public health concern. Due to the increasing numbers of illicit designer benzodiazepines encountered in the US supply chain, there is a need to develop robust analytical methods that can rapidly detect these chemicals. Suspect counterfeit tablets, powders, or liquid formulations were first screened using Raman spectroscopy and surface-enhanced Raman scattering spectroscopy (SERS) for the presence of legal or illicit benzodiazepines, and then further analyzed using Fourier-transform infrared (FT-IR) spectroscopy and liquid chromatography with tandem mass spectrometric detection (LC-MS). Several microextraction procedures were developed and used to extract benzodiazepines from samples prior to SERS, FT-IR, and LC-MS analysis. Conventional Raman analyses using handheld Raman spectrometers afforded the ability to examine samples through enclosed plastic bags but were only able to detect high concentrations of various benzodiazepines in the suspect samples. The developed SERS methods were sufficient for detecting at least one benzodiazepine in the low-dose suspect samples, thereby allowing prioritization using other analytical tools that require more sample preparation and time-consuming analyses. The use of FT-IR spectroscopy coupled with extraction and spectral subtraction was found to be selective to multiple benzodiazepines and various excipients in the analyzed samples. This study demonstrated that the developed SERS and FT-IR procedures could be used in satellite laboratories to screen suspect packages at ports of entry and prioritize samples for additional laboratory-based analyses in an effort to prevent dangerous and illicit pharmaceutical products from reaching the US supply chain.

Simultaneous Temperature Measurements and Aerosol Collection During Vaping for the Analysis of Δ9-Tetrahydrocannabinol and Vitamin E Acetate Mixtures in Ceramic Coil Style Cartridges.

Incidence of e-cigarette, or vaping, product use-associated lung injury (EVALI) has been linked to the vaping of tetrahydrocannabinol (THC) products to which vitamin E acetate (VEA) has been added. In this work we vaped THC/VEA mixtures at elevated power levels using a variety of ceramic coil vaping cartridges and a commercially available vaping device, while simultaneously measuring temperature and collecting the vaporized condensate. The collected vapor condensate was analyzed for evidence of VEA decomposition by GC/MS, GC/FT-IR/MS, and LC-APCI-HRMS/MS. Mean temperature maxima for all examined cartridges at the selected power exceeded 430°C, with a range of 375-569°C, well beyond that required for thermal decomposition of VEA. The percent recovery of VEA and Δ9-THC from the vaporized mixture in six cartridges ranged from 71.5 to 101% and from 56.4 to 88.0%, respectively. Analysis of the condensed vaporized material identified VEA decomposition products duroquinone (DQ), 1-pristene, and durohydroquinone monoacetate (DHQMA); a compound consistent with 4-acetoxy-2,3,5-trimethyl-6-methylene-2,4-cyclohexadienone (ATMMC) was also detected. The concentration of DQ produced from vaporization of the THC/VEA mixture in one cartridge was found to be 4.16 ± 0.07 µg per mg of vapor condensate.

Rapid determination of eight benzodiazepines in suspected counterfeit pharmaceuticals using surface-enhanced Raman scattering with handheld Raman spectrometers.

The excessive prescription of benzodiazepines is putting more people at risk of dependence on these drugs and is exacerbating the fatal overdose toll of opioids. A rapid and sensitive SERS method has been developed for trace detection of select benzodiazepines in low-dosage suspect counterfeit tablets, capsules, and injectable solutions using two different portable handheld Raman spectrometers equipped with either a 785-nm laser or a 1064-nm laser. A total of 169 samples and blanks were examined using five handheld Raman spectrometers, which provided data set of 729 examinations. The extraction/SERS procedures yielded true positive rates above 90% for alprazolam, diazepam, and midazolam using the 1064-nm device and yielded true positive rates above 95% for alprazolam, clonazepam, diazepam, estazolam, midazolam, and temazepam using the 785-nm device; however, the extraction/SERS procedures yielded true positive rates below 60% for lorazepam and triazolam. The minimum concentration (Cmin ) of the benzodiazepine standards that reproducibly yielded a positive match ranged from 1 to 10 µg/ml using the 1064-nm laser device and from 0.5 to 50 µg/ml using the 785-nm laser device. For the analysis of authentic and suspect counterfeit tablets containing these benzodiazepines, the measured Cmin ranged between 10 and 15 µg per tablet or capsule for 1064-nm laser device and 1-100 µg per tablet or capsule for 785-nm laser device. The developed methods are simple, rapid, and ideal for screening suspect benzodiazepine-containing pharmaceutical products at satellite laboratories located within or near international mail facilities and express courier hubs.

Evaluation of "Toolkit" consisting of handheld and portable analytical devices for detecting active pharmaceutical ingredients in drug products collected during a simultaneous nation-wide mail blitz.

A "toolkit" consisting of a handheld Raman spectrometer equipped with a 1064 nm laser, a portable Fourier transform infrared (FT-IR) spectrometer and a portable direct analysis in real-time mass spectrometer (DART-MS) was employed in a laboratory setting to examine 82 representative products collected during a nationwide mail blitz for the presence of APIs. These results were compared to those obtained using laboratory-based methods; 8 of the products were not found to contain APIs and 74 of the products were found to contain a total of 88 APIs (65 of the 88 APIs were unique). The individual performance of each device and combined performance of the three-device toolkit were evaluated with regard to true positives, true negatives, false positives and false negatives. Using this toolkit, 81 (92.0 %) of the APIs were detected by at least one technique and 47 (64.8 %) of the APIs were detected by at least two techniques. Seven false negatives (8.0 %) were encountered and while the toolkit yielded 12 false positives, no false positives were detected by more than one technique. Overall, this study demonstrated that when the toolkit detects an API using two or more devices, the results are as reliable as those generated by a full-service laboratory.

Evaluation of four field portable devices for the rapid detection of mitragynine in suspected kratom products.

The development of a method for the rapid screening of food and drug products for constituents such as mitragynine, the most abundant alkaloid found in Mitragyna speciosa (kratom) plant leaves, has become increasingly important. The use of kratom is said to produce stimulant or narcotic effects and poses risks of addiction, abuse, and dependence, much like other opioids. Direct Analysis in Real Time with thermal desorption mass spectrometry (DART-TD-MS), hand-held mass spectrometry, portable ion mobility spectrometry (IMS), and portable Fourier-transform infrared spectroscopy (FT-IR) were each evaluated as field-deployable screening techniques for the detection of mitragynine in food and drug products. These devices offer the potential for rapid, early detection of mitragynine in suspect products entering the United States through international mail facilities and other ports of entry. Ninety-six kratom products, including capsules, bulk powder, and bulk plant material, were analyzed by either direct sampling of the solid material or by solvent extraction. True and false positive and negative results are reported, based on comparison to results from qualitative screening using gas chromatography with mass spectral detection (GC-MS), liquid chromatography with mass spectral detection (LC-MS), and/or quantitative screening using high-performance liquid chromatography with ultraviolet detection (HPLC-UV), with a discussion of the assessment of each technique for use in the field. Each device demonstrated attributes that would be favorable for use in screening of suspected mitragynine-containing products at places like ports of entry, and simultaneous deployment of two or more of these devices as part of a workflow would be the most effective for rapid screening of these products. This combination of rapid screening orthogonal techniques suited to a non-laboratory environment will allow onsite destruction of products found to contain mitragynine.

Trace level detection of select opioids (fentanyl, hydrocodone, oxycodone, and tramadol) in suspect pharmaceutical tablets using surface-enhanced Raman scattering (SERS) with handheld devices.

The opioid crisis in the USA has resulted in over 702,000 overdose fatalities between 1999 and 2017 and can be attributed to over-prescription of opioids and abuse of synthetic opioids in combination with other illicit drugs. A rapid and sensitive SERS method has been developed for trace detection of opioids including fentanyl, hydrocodone, oxycodone, and tramadol in low-dosage suspect tablets using two different handheld Raman spectrometers equipped with 785 and 1064 nm lasers. The method involves a micro-extraction procedure using 10% methanol in deionized water, followed by filtration and addition of colloidal silver and aqueous KBr, resulting in a mixture that can be measured directly via a glass vial. The lowest concentration (Cmin ) of fentanyl, tramadol, oxycodone, and hydrocodone standards that yielded a positive match was 250 ng/ml, 5, 10, and 10 µg/ml using the 1064 nm laser device and 100 ng/ml, 1 µg/ml, 500 ng/ml, and 750 ng/ml using the 785 nm laser device, respectively. For the analysis of suspect tablets containing these opioids, the Cmin ranges between 5 and 75 µg/ml for 1064 nm laser device and 1 and 50 µg/ml for 785 nm laser device. The overall positive identification rate for all the opioids studied in the suspect counterfeit tablets analyzed ranged from 80% to 100%. The use of SERS for rapid chemical identification at remote sampling sites, such as international mail facilities (IMFs) and express courier hubs (ECHs), provides a rugged, simple, and practical method applicable for point-of-entry sampling and analysis.

Detection of Mitragynine in Mitragyna Speciosa (Kratom) Using Surface-Enhanced Raman Spectroscopy with Handheld Devices.

A simple, quick, selective, sensitive, and effective field-friendly method capable of being used by nonexperts has been developed for detecting mitragynine in Mitragyna speciosa (kratom) using surface-enhanced Raman spectroscopy (SERS). Over 100 samples and blanks (known to be either positive or negative for the presence of mitragynine) were examined in duplicate using five identical handheld Raman spectrometers, which provided a data set of over 1,000 examinations. Based on the results of these analyses, the method yielded a true-positive rate of 99.3%, a true-negative rate of 97.9%, a false-positive rate of 2.1%, and a false-negative rate of 0.7%. The average minimum detectable concentration (Cm ) of mitragynine that reproducibly yielded a match for one of the library spectra on all five instruments was determined to be 342 ng/mL (ppb). This Cm value is a conservative estimate considering that the extraction process was not fully optimized by this study, which was not necessary since the Cm value achieved was well below typical mitragynine concentrations in kratom (1.3-2.3%). The method is ideal (i) for prioritizing samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify mitragynine and (ii) for field use at international mail facility (IMF) satellite laboratories to help interdict kratom and prevent this dangerous product from reaching the U.S. supply chain.

Evaluation of Suspected Counterfeit Pharmaceutical Tablets Declared to Contain Controlled Substances Using Handheld Raman Spectrometers.

This study describes the performance of handheld Raman devices for determining whether suspect pharmaceutical tablets declared to contain controlled substances were consistent with authentic (CWA) or not consistent with authentic (NCWA) tablets using a simple, rapid, field-friendly method capable of being used by nonexperts. Twenty-five authentic products and 84 known NCWA tablets were examined using three "parent" devices for a total of 327 analyses. On average, the parent devices yielded a true pass rate of 100%, a true fail rate of 98.4%, a false pass rate of 1.6%, and a false fail rate of 0%. The methods/libraries were then transferred to 13 identical "daughter" devices, which were used to examine 10 suspect finished dosage forms in duplicate (six known NCWA tablets and four authentic tablets) for a total of 260 measurements. On average, the daughter devices had a true pass rate of 100%, a true fail rate of 95.5%, a false pass rate of 4.5%, and a false fail rate of 0.0%. These data demonstrate that the parent-daughter electronic transfer method was successful, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices. The methods can then be used to (i) prioritize samples for additional testing using other more time-consuming laboratory-based techniques needed to detect and quantify active ingredients and (ii) help support the interdiction of dangerous tablets at ports of entry, thereby preventing them from reaching the supply chain.

Hydrogen Bonding between Tetrahydrocannabinol and Vitamin E Acetate in Unvaped, Aerosolized, and Condensed Aerosol e-Liquids.

Vitamin E acetate (VEA) has recently been identified as a potential chemical of concern in the investigation of e-cigarette, or vaping, product use associated lung injury (EVALI). According to the Centers for Disease Control and Prevention (CDC), most patients report a history of using tetrahydrocannabinol (THC)-containing e-cigarette or vaping products; approximately 50% of the THC-containing vaping products examined by the Food and Drug Administration (FDA) in this investigation have been found to contain VEA. This letter demonstrates that THC and VEA exist in the unvaped e-liquids, vaped e-liquids, and the aerosol produced from vaporizing the mixture, as a hydrogen bonded THC/VEA complex linked by the THC hydroxyl and VEA carbonyl groups. Additional work should therefore be considered to investigate what happens to this complex in the lungs.

Identification of Opioids and Related Substances using Handheld Raman Spectrometers.

This study describes the performance of handheld Raman devices for detecting one hundred opioids and related substances including fentanyl and several analogs. Using a single "parent" device, signatures (spectra) with excellent signal-to-noise ratios were generated using <5 mg of most compounds. The signatures were added to a method (library), which was electronically transferred to three "daughter" devices. The devices were able to discriminate different salt forms and isomers. On average, the daughter devices yielded a true-positive rate of 97.3% for generating an alarm for opioids and were 93.3% effective for correctly identifying the opioid. The devices yielded true-negative, false-positive and false-negative rates of 100%, 0%, and 2.7%, respectively, where false negatives were due to weak signal and fluorescence. These data demonstrate that the parent-daughter electronic transfer method was successful and effective, which permits the ability to develop methods in the laboratory that can be seamlessly pushed out to field devices.

Identification of the designer steroid Androsta-3,5-diene-7,17-dione in a dietary supplement.

A liquid chromatography-mass spectrometry (LC-MS) screen for known anabolic-androgenic steroids in a dietary supplement product marketed for "performance enhancement" detected an unknown compound having steroid-like spectral characteristics. The compound was isolated using high performance liquid chromatography with ultraviolet detection (HPLC-UV) coupled with an analytical scale fraction collector. After the compound was isolated, it was then characterized using gas chromatography with simultaneous Fourier Transform infrared detection and mass spectrometry (GC-FT-IR-MS), liquid chromatography-high resolution accurate mass-mass spectrometry (LC-HRAM-MS) and nuclear magnetic resonance (NMR). The steroid had an accurate mass of m/z 285.1847 (error-0.57 ppm) for the protonated species [M + H]+ , corresponding to a molecular formula of C19 H24 O2 . Based on the GC-FT-IR-MS data, NMR data, and accurate mass, the compound was identified as androsta-3,5-diene-7,17-dione. Although this is not the first reported identification of this designer steroid in a dietary supplement, the data provided adds information for identification of this compound not previously reported. This compound was subsequently detected in another dietary supplement product, which contained three additional active ingredients.

Forensic Drug Identification, Confirmation, and Quantification Using Fully Integrated Gas Chromatography with Fourier Transform Infrared and Mass Spectrometric Detection (GC-FT-IR-MS).

This manuscript is a continuation of a recent study that described the use of fully integrated gas chromatography with direct deposition Fourier transform infrared detection and mass spectrometric detection (GC-FT-IR-MS) to identify and confirm the presence of sibutramine and AB-FUBINACA. The purpose of the current study was to employ the GC-FT-IR portion of the same instrument to quantify these compounds, thereby demonstrating the ability to identify, confirm, and quantify drug substances using a single GC-FT-IR-MS unit. The performance of the instrument was evaluated by comparing quantitative analytical figures of merit to those measured using an established, widely employed method for quantifying drug substances, high performance liquid chromatography with ultraviolet detection (HPLC-UV). The results demonstrated that GC-FT-IR was outperformed by HPLC-UV with regard to sensitivity, precision, and linear dynamic range (LDR). However, sibutramine and AB-FUBINACA concentrations measured using GC-FT-IR were not significantly different at the 95% confidence interval compared to those measured using HPLC-UV, which demonstrates promise for using GC-FT-IR as a semi-quantitative tool at the very least. The most significant advantage of GC-FT-IR compared to HPLC-UV is selectivity; a higher level of confidence regarding the identity of the analyte being quantified is achieved using GC-FT-IR. Additional advantages of using a single GC-FT-IR-MS instrument for identification, confirmation, and quantification are efficiency, increased sample throughput, decreased consumption of laboratory resources (solvents, chemicals, consumables, etc.), and thus cost.

Development and implementation of a pass/fail field-friendly method for detecting sildenafil in suspect pharmaceutical tablets using a handheld Raman spectrometer and silver colloids.

A simple, fast, sensitive and effective pass/fail field-friendly method has been developed for detecting sildenafil in suspect Viagra and unapproved tablets using handheld Raman spectrometers and silver colloids. The method involves dissolving a portion of a tablet in water followed by filtration and addition of silver colloids, resulting in a solution that can be measured directly through a glass vial. Over one hundred counterfeit Viagra and unapproved tablets were examined on three different devices during the method development phase of the study. While the pass/fail approach was found to be 92.6% effective on average, the efficacy increased to 97.4% on average when coupled with the software's "Discover Mode" feature that allows the user to compare a suspect spectrum to that of a stored sildenafil spectrum. The lowest concentration of sildenafil in a water/colloid solution that yielded a "Pass" was found to be 7.6µg/mL or 7.6 parts per million (ppm). For the analysis of suspect tablets, this value was found to be as low as 10µg/mL and as high as 625µg/mL. This variability was likely related to the tablet formulation, e.g., concentration of sildenafil, presence and concentration of water-soluble and/or water-insoluble ingredients. However, since most counterfeit Viagra and unapproved tablets contain >50mg sildenafil per tablet, such low concentrations will not be encountered often. Limited in-lab and in-field validation studies were conducted in which analysts/field agents followed the procedure outlined in this study for small sample sets. These individuals were provided with written instructions, a ∼20min demonstration regarding how to perform the procedure and use the instrument, and a kit with field-friendly supplies (purified bottled water from a local grocery store, disposable plastic pipettes, eye-dropper with a silver colloid solution, etc.). The method proved to be 98.3% and 91.7% effective for the in-lab and in-field validation studies, respectively, which demonstrated the ruggedness, simplicity and practicality of the method.

Simultaneous Orthogonal Drug Detection Using Fully Integrated Gas Chromatography with Fourier Transform Infrared Detection and Mass Spectrometric Detection.

Analytes that co-elute and yield nearly identical electron ionization (EI) mass spectra, as well as analytes that yield non-specific EI fragmentation patterns, have been identified using fully integrated gas chromatography with direct deposit Fourier transform infrared detection and mass spectrometric detection (GC/FT-IR/MS). While the IR detector proved to be more selective for identifying analytes such as synthetic cannabinoids and weight loss drugs, it was limited by a relatively high detection limit of 8.4 parts per million (ppm) for non-targeted identification of sibutramine based on a single injection but was reduced to 840 parts per billion (ppb) for targeted identification of sibutramine by redepositing ten injections along the same track. The MS detector was less selective for identifying these analytes but yielded non-targeted and targeted detection limits of approximately 84 ppb and 8.4 ppb, respectively, which corresponded to a 100-fold advantage compared to the IR detector. Overall, the results of this study demonstrate that the advantages of each detector compensate for the limitations of the other, which allows a wider range of analytes and concentrations to be examined using a fully integrated GC/FT-IR/MS instrument compared to what can be examined using GC/IR or GC/MS independently. Not only does this approach reduce consumption of laboratory resources and time, it provides IR and MS information on the same sample, which is important for forensic analyses that require data from two or more orthogonal techniques to make an identification.

Isolation and structural characterization of a new tadalafil analog (chloropropanoylpretadalafil) found in a dietary supplement.

A screen for known PDE-5 inhibitors in a dietary supplement product marketed for "enhanced sexual performance" detected a compound that structurally resembled chloropretadalafil, a known analog of tadalafil. The compound was isolated from the supplement matrix using high performance liquid chromatography with ultraviolet detection (HPLC-UV) and a fraction collector, and was further characterized using gas chromatography with Fourier Transform infrared detection and mass spectral detection (GC/FT-IR/MS), as well as high resolution mass spectrometry (HRMS). The analog had an accurate mass of m/z 441.1216 (error is 0.8706ppm) for the protonated species [M+H](+), corresponding to a molecular formula of C23H22ClN2O5. HRAM and GC/FT-IR/MS mass spectral fragmentation data suggested that the modification is a chloropropanoyl moiety extending from the nitrogen on the piperidine ring of chloropretadalafil. The proposed new analog has been named chloropropanoylpretadalafil.

Analysis of Counterfeit Coated Tablets and Multi-Layer Packaging Materials Using Infrared Microspectroscopic Imaging.

An effective method for detecting and characterizing counterfeit finished dosage forms and packaging materials is described in this study. Using attenuated total internal reflection Fourier transform infrared spectroscopic imaging, suspect tablet coating and core formulations as well as multi-layered foil safety seals, bottle labels, and cigarette tear tapes were analyzed and compared directly with those of a stored authentic product. The approach was effective for obtaining molecular information from structures as small as 6 µm.

Forensic Analysis of Human Autopsy Tissue for the Presence of Polydimethylsiloxane (Silicone) and Volatile Cyclic Siloxanes using Macro FT-IR, FT-IR Spectroscopic Imaging and Headspace GC-MS.

This study describes effective and straightforward primary and secondary methods for the detection of silicone in human autopsy tissue. The primary method is polydimethylsiloxane (PDMS) specific and employs either macro-attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy for samples with a high PDMS concentration (relative to that of the matrix) or micro-FT-IR spectroscopic imaging in a reflection/absorption modality for samples with a low PDMS concentration. Although the secondary method is not PDMS specific, it employs headspace gas chromatography with mass spectrometric detection (HS/GC-MS) for the detection of low molecular weight volatile cyclic siloxanes (VCS), which are characteristic marker compounds for PDMS. Overall, the combined results from the primary and secondary analyses provide reliable evidence for the presence of silicone.