Drug Samples Research Articles

Analytical Method Development and Validation of RP-HPLC Method for Estimation of Pazopanib Drug Sample and It’s Dosage Form

The study focuses on developing and verifying a cost-effective Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) technique for quantifying Pazopanib HCl in both bulk and tablet forms. The study aims to develop a cost-effective approach for routine quality control analysis by utilizing the simplicity and wide accessibility of HPLC. A Shimadzu C18 column (5 µm, 250 mm × 4.6 mm) was successfully used to separate Pazopanib HCl via chromatography. The mobile phase consisted of a mixture of Potassium dihydrogen phosphate in water (pH 2.9, corrected with Phosphoric Acid) and Acetonitrile in a ratio of 25:75 v/v. The isocratic elution mode was utilized with a flow rate of 1.0 mL/min, a column temperature of 25°C, and an injection volume of 20 µL. Pazopanib hydrochloride had a retention period of 2.8 minutes when measured at an isobestic wavelength of 215 nm. The described RP- HPLC technique showed exceptional specificity, accuracy, precision, linearity, and durability, rendering it a viable instrument for Pazopanib HCl tablets' regular quality control analysis. This method is both efficient in terms of analytical performance and economically profitable, making it very suitable for frequent pharmaceutical analysis.

Assessment of Toxic Metals in Commonly Used Energy-Stimulating Herbal Drugs Manufactured in Rajshahi City, Bangladesh

Having been a common healthcare distress, erectile dysfunction is upsetting the quality of life of men from all walks of life. Along with allopathic therapy, a sizable number of patients opt for energy-stimulating herbal drugs (ESHDs) to treat the ailment. However, a global threat vestige for metal contamination in plant-based drugs at above threshold concentrations. Investigation into metal toxicity through samples from Bangladesh is scarce. Six metals: chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), lead (Pb), and zinc (Zn) were probed in 25 energy stimulating herbal drug samples by flame atomic absorption spectrophotometer (F-AAS). Metal content was below detection limit, 51.86 ± 0.07 ppm for Cr, below detection limit, 7.26 ± 0.07 ppm for Cu, 3.41 ± 0.14 – 59.00 ± 0.09 ppm for Fe, 3.54 ± 0.09 – 26.16 ± 0.04 ppm for Mn, below detection limit to 67.34 ± 0.58 ppm for Pb, and below detection limit 27.79 ± 0.07 ppm for Zn. Exposure assessment found Cr and Pb concentrations in the objectionable limits in 12% and 20% of the samples, respectively. This study signifies concern metal toxicity in ESHDs which demands additional probes in the future for other samples to guarantee safe consumption of the drugs.

DrogoFinder: An open-source graphical user interface for the identification of illicit drugs using infrared spectroscopy

The development of Free and Open-Source Software (FOSS) is being increasingly recognized as an indispensable resource for the development, validation, and replication of analytical methodologies and tools. In this context, the use of Attenuated Total Reflectance Infrared (ATR-IR) spectroscopy for the in-situ identification of drugs requires software for the treatment of spectroscopic data, including spectral quality controls, the subtraction of possible excipients, and the comparison with well-defined libraries that can be complex and limits its application on the field analysis by non-expert users. Here we describe a user-friendly FOSS for drug identification that can be operated in an intuitive way, including automatic features such as i) quality controls that warn the user from possible technical problems during spectrum acquisition (e.g. water vapour, contaminated background), ii) the subtraction of the contribution of excipients and other substances present on the sample, and iii) the creation of custom and updated cloud-based libraries to deal with the great number of new psychoactive substances (NPS) that are constantly being developed and introduced for their consume. The proposed application was tested by expert and non-expert users with spectra from 42 drug samples measured in situ in a music festival and 39 seized samples measured in a laboratory. Non-expert users were able to flag technical problems in the spectra and to perform excipient subtractions automatically, obtaining drug identifications that matched those ones obtained by reference methods and dedicated commercial software. We share both, the code, and a standalone Windows app to reach worldwide users and scientists interested in the identification of drugs.

Development of Fast Release Aminated Tamarind Gum Carrier-based Solid Dispersion containing Tablets of Ketoconazole for Solubility and Dissolution Rate Enhancement

This work enhances the solubility as well as dissolution of the biopharmaceutical classification system (BCS) II drug ketoconazole (KTZ) using fast-dissolving tablets that contain solid aminated tamarind gum (ATG). In the first stage amination of the tamarind gum was done to form ATG and which was confirmed by the presence of characteristic peaks using Fourier-transform infrared spectroscopy (FTIR). DSC-TGA analysis showed a weight loss with 3.91% at 100℃, 54.42% loss at 235 to 425℃ and 90% at 485℃. The proton nuclear magnetic resonance (1H-NMR) showed all resonance peaks observed in ATG. The XRD analysis of ATG confirmed the amorphous nature of the material. The second phase involved developing KTZ-loaded solid dispersion (SD) using the kneading process. KTZ SD showed drug content of 94.55 to 97.21%. SD of KTZ manufactured with TG showed 2.55 to 23.82-fold solubility enhancement in water while in case of SD with ATG showed 28.51 to 33.19-fold solubility enhancement. KTZ had a 32% dissolution rate in the pure drug sample, but the SD5 formulation showed a complete release of solid dispersion in 120 minutes. In FTIR, the disappearance of the peak signifies the production of solid dispersion and the drug’s transformation from a crystalline to an amorphous state. Powder X-ray diffraction (PXRD) analysis of solid dispersions reveals a notable decline in crystallinity, as shown by the removal of strong, distinguishing peaks. The scanning electron microscope (SEM) analysis confirmed the successful development of the SD in which KTZ was observed to be dispersed in a polymeric carrier. Optimized KTZ-loaded SD were utilized in fast-dissolving tablets as the third phase. When compared to the drug release achieved from solid dispersions, it was discovered that the dissolving characteristics of all formulation batches were improved.

A strategy for the detection of benzodiazepine drugs using low-resolution paper-spray mass spectrometry for harm reduction drug checking.

The ability to detect newly emerging substances is of great importance in reducing harms for people who use drugs. New psychoactive substances including novel benzodiazepines in the illicit drug supply have been linked to high rates of overdose deaths while complicating drug checking as an overdose prevention strategy. Paper-spray mass spectrometry (PS-MS) has emerged as a novel strategy to rapidly detect trace components in street drug samples. While targeted, low-resolution PS-MS methods have proven effective, newly emerging substances are often missed. To address this, a method was applied to low-resolution full-scan PS-MS data to aid in the early detection and identification of novel benzodiazepines in the unregulated drug supply. Using the developed method, true positives rates of 0.89 and 0.75 were achieved for bromazolam and etizolam in street samples obtained in a community drug checking service. The applicability of the method was further demonstrated for a novel benzodiazepine, desalkylgidazepam, that has recently emerged in the illicit drug supply.

Emergency care drugs' chemical stability after eight weeks’ deployment in the prehospital setting

Temperature conditions vary in emergency service vehicles, which may pose a risk to the integrity of the drugs on board, possibly rendering them ineffective and increasing morbidity and mortality in patients. AimThis study assessed the stability of four emergency care drugs (adrenaline, etomidate, ketamine, and rocuronium) after eight weeks of deployment in the prehospital context. MethodsThe study adopted a longitudinal quantitative design to evaluate the chemical stability of emergency care drugs. The study was conducted at four emergency medical service bases in Ballito, Durban and Pietermaritzburg, South Africa. The primary outcome was the relative reduction in drug concentration from the labelled concentration after four and eight weeks. High-performance liquid chromatography-mass spectrometry (HPLC-MS) analysed samples to determine the concentration of active ingredients in the drug samples. ResultsHPLC analysis was done on 176 samples. The ambient temperature ranged from 18.7 to 44 °C in the first four weeks, averaging 26.8 °C ± 3.0. At 4 and 8 weeks, Adrenaline decreased 24.93 % and 22.73 %, respectively. Etomidate's control had 3.06 mg/ml, not the 2 mg/ml on the bottle. After 4 and 8 weeks, the samples had 3.10 and 3.15 mg/ml active components, respectively. Ketamine degraded over 30 % after four weeks but not beyond that. The Ketamine package states 10 mg/ml. However, we found 17.46 mg/ml. Rocuronium was 6.45 mg/ml in the control, although the manufacturer specified 10 mg/ml. At four weeks, the concentration was 6.70 mg/ml; at eight weeks, 6.56. ConclusionThis study suggests that adrenaline and ketamine degrade by more than 20 % within four weeks of deployment in the prehospital field, whereas etomidate and rocuronium remain stable after eight weeks.

Assessment of two brands of fentanyl test strips with 251 synthetic opioids reveals “blind spots” in detection capabilities

BackgroundFentanyl test strips (FTS) are a commonly deployed tool in drug checking, used to test for the presence of fentanyl in street drug samples prior to consumption. Previous reports indicate that in addition to fentanyl, FTS can also detect fentanyl analogs like acetyl fentanyl and butyryl fentanyl, with conflicting reports on their ability to detect fentanyl analogs like Carfentanil and furanyl fentanyl. Yet with hundreds of known fentanyl analogs, there has been no large-scale study rationalizing FTS reactivity to different fentanyl analogs.MethodsIn this study, 251 synthetic opioids—including 214 fentanyl analogs—were screened on two brands of fentanyl test strips to (1) assess the differences in the ability of two brands of fentanyl test strips to detect fentanyl-related compounds and (2) determine which moieties in fentanyl analog chemical structures are most crucial for FTS detection. Two FTS brands were assessed in this study: BTNX Rapid Response and WHPM DanceSafe.ResultsOf 251 screened compounds assessed, 121 compounds were detectable at or below 20,000 ng/mL by both BTNX and DanceSafe FTS, 50 were not detectable by either brand, and 80 were detectable by one brand but not the other (n = 52 BTNX, n = 28 DanceSafe). A structural analysis of fentanyl analogs screened revealed that in general, bulky modifications to the phenethyl moiety inhibit detection by BTNX FTS while bulky modifications to the carbonyl moiety inhibit detection by DanceSafe FTS. ConclusionsThe different “blind spots” are caused by different haptens used to elicit the antibodies for these different strips. By utilizing both brands of FTS in routine drug checking, users could increase the chances of detecting fentanyl analogs in the “blind spot” of one brand.

First drug-checking study at an electronic festival and fentanyl detection in the central region of Mexico

BackgroundPerception of drug adulteration has increased in Mexico, but there is little research on adulterants and toxicity. The aim of this study was to identify drug composition in an electronic music outdoor festival nearby Mexico City.MethodsThe participants completed a questionnaire with demographic data, harm reduction strategies, drug-use patterns, history, and the drug they expected to find. We took a small sample of each substance and prepared it for drug checking. A two-section drug testing station was placed within the grounds of the festival. Interaction with participants occurred at the front part. Drug checking was conducted at the rear part. The service was free of charge, voluntary and confidential. Forty persons aged 22 to 48 years participated (mode = 28), of which 92.5% were male, most (82.5%) were single. Through the Substance Analysis Program of “ReverdeSer Collective,” we conducted the testing with the attendants that provided 51 drug samples, following ethical and biosafety protocols. We used colorimetry, Fourier Transform Infrared Spectroscopy, and fentanyl immunoassay strips for sample analysis.ResultsSubstances of choice among attendants were psychostimulants (MDMA and other amphetamine-like drugs) and hallucinogens. Most samples contained what the users expected plus adulterants. Main adulterants were methylene-dioxy-ethyl-amphetamine, methylene-dioxy-propyl-amphetamine, hydroxyamphetamine, and the selective serotonin reuptake inhibitor venlafaxine. Fentanyl was present in 2 out of 4 cocaine samples and in 14 of the 22 confirmed MDMA samples.ConclusionsSome of the adulterants found pose serious health risks, especially fentanyl, amphetamine-like substances, and venlafaxine. Therefore, it is urgent to monitor these adulterants at electronic music festivals and to implement prevention, treatment, and harm reduction public policies. Naloxone distribution and drug-assisted therapies should be part of government programs in Mexico.

Paper-based visualization of auramine O in food and drug samples with carbon dots-incorporated fluorescent microspheres as sensing element.

A paper-based assay for visualization of auramine O (AO) was for the first time established by using CFMs as a ratiometric fluorescent probe (RFP). The CFMs were melamine formaldehyde microspheres (MFMs) incorporated with carbon dots (CDs), where the CDs species as sensing units and MFMs as a signal amplification carrier. The proposed RFP can quantitatively measure AO content from 0.0 to 10.0μM and exhibited an ultralow limit of detection (LOD, 15.7nM). In particular, obvious luminescence color change of CFMs from blue to green was perceived with naked-eyes and therefore, a solution-based and a paper-based visualization platform were respectively proposed for on-site visual detection of AO with LODs of 1.15μM and 0.83μM, separately. Finally, those fluorescence methods were adopted in sensitively quantitative measurement of AO within various food and drug samples, providing new prospects for analysts and technical support in food quality monitoring.

Detection of 41 Drugs and Metabolites in Urine with Internal Hydrolysis Control by Liquid Chromatography-Tandem Mass Spectrometry.

Regular monitoring of pain management and substance use disorder patients through urine drug screening is important for assessing patient compliance with prescribed drugs and abstinence fromnon-prescribed drugs. Sample analysis is commonly performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as multiple drugs and metabolites can be monitored from one sample. However, challenges faced indeveloping an LC-MS/MS method for multiple analytes in urine include variability in matrix and concentration from sample to sample and variable chemistry of many pain management drugs and associated metabolites affecting accuracy and precision of results. We describe here an LC-MS/MS method for analysis of 41 drugs and metabolites commonly prescribed for pain management patients. The developed method uses enzymatic hydrolysis followed by cation exchange solid phase extraction. Resorufin-glucuronide is used as an internal hydrolysis control to monitor hydrolysis in each patient sample and minimize false negatives. Analysis was performed using an Agilent 6470 mass spectrometer in dynamic multiple reaction monitoring mode.

Alumina nanoparticles modified electrode for sensitive detection of tinidazole in drug and urine samples

We provide a simple, robust, and novel method based on a stable dispersion of α-alumina (Al2O3) nanoparticles to modified glassy carbon electrode (GCE) for the quantitative detection of the tinidazole (TIN) drug, a derivative of the nitroimidazole moiety. Because of the adverse effects due to the consumption of large quantities, we need an analytical tool for quantitative detection. A well-defined reduction peak potential for TIN was observed at − 0.65 V vs. Ag/AgCl with enhanced catalytic peak at Chit@alumina modified GCE at neutral pH (0.1 M PBS). Under the experimental conditions, the fabricated electrode shows a broad linear response to concentrations of TIN in the ranges of 6.0 × 10−9 M to 36 × 10−6 M with correlation coefficient of 0.9974. The lowest detection limit was identified as 16 nM, and the current sensitivity was measured to be 12.16 μA∙ nM−1∙cm−2. Furthermore, the synthesized voltammetic sensor has adequate recovery ranges, remarkable anti-interference performance against biomarkers and other electroactive molecules, and also exhibits good storage stability and repeatability. The developed sensor's application studies were successfully used to detect TIN in biological specimens and drug tabulations.

Simultaneous electrochemical detection of L-dopa and hydrogen peroxide by poly (amido amine) dendrimer/poly (neutral red) modified sensor

In a biological process, hydrogen peroxide (H2O2) plays an important role as a by-product of enzymatic reactions, and levodopa (L-dopa) is crucial for the production of dopamine in living organisms. These two different chemical compounds are essential for human health, and it is important to monitor their concentration in real samples, for example in the food and pharmaceutical industries. In this research, we fabricated a poly(amidoamine)-dendrimer/poly(neutral red) (PAMAM/PNR) modified electrode and used it to simultaneously determine the electrochemical oxidation of L-dopa and the reduction of H2O2. The PAMAM/PNR-modified sensor electrode showed a linear response from 0.08 to 2400 μM for L-dopa with a LOD (lower limit of detection) of 0.026 μM (S/N = 3). In addition, the PAMAM/PNR modified electrode showed a linear response from 4.6 μM to 2208 μM for H2O2 with an LOD of 1.5 μM (S/N = 3) and using the square wave voltammetry method. The present modified sensor electrode was successfully tested in practical application with beverages and drug samples with acceptable recoveries.

OMNI: Gas Chromatograph Captures Seven Common PET Radiotracer Analytes in under 5 Minutes.

A novel gas chromatography method was developed using automatic injections to identify and quantify the amount of residual solvents or analytes in samples of fluorine-18 and carbon-11 radiopharmaceuticals. This approach evaluates seven analytes in less than 5 versus 13 min of acquisition time. The method additionally includes a 3 min bakeout to aid in the removal and carry-over of higher-boiling impurities. Chromatographic parameters such as column temperature, hold time, column pressure, flow rate, and split ratios were adjusted and optimized to analyze radioactive drug samples containing analytes which include methanol, ethanol, acetone, acetonitrile, triethylamine, N,N-dimethylformamide, and dimethyl sulfoxide. The relative standard deviation for each solvent was determined to be no greater than 1.6%. The method limit of detection (LOD) and limit of quantification (LOQ) were between 0.053 and 0.163 and 0.000 (5.791 × 10-6) and 0.520 mg/mL, respectively. This GC technique, using flame ionization detection (FID), was validated and is currently employed for the routine quality control of all approved IND and RDRC PET radiopharmaceuticals at our center.

Costing analysis of a point-of-care drug checking program in Rhode Island

BackgroundDrug checking is a harm reduction strategy that provides greater awareness and information about the drug supply to the community. While fentanyl test strips are low-cost and available in most parts of the U.S., community-based organizations are considering using more sophisticated technologies, such as Fourier-transform infrared (FTIR) spectroscopy to test drugs. FTIR can detect multiple substances in a non-destructive manner that can be rapidly communicated to the end user by a trained technician, however implementation costs in community-based settings have not been assessed. MethodsWe conducted a costing analysis of a new pilot drug checking service that employed an FTIR spectrometer, fentanyl test strips and confirmatory testing in Rhode Island from January 2023-May 2023. We used microcosting methods to determine the overall cost during this period and cost per drug checked, reflecting realistic service capacity. ResultsAmong 101 drug samples that were voluntarily submitted and tested, 53% tested positive for fentanyl, 39% for cocaine, 9% for methamphetamine and 13% for xylazine, a powerful sedative. The total cost during this period was $71,044 and the cost per drug checked was $474, though sensitivity analyses indicated that the cost would rise to $78,058 - $83,058 or $544 - $593 for programs needing to pay for specialized training. ConclusionsThese findings demonstrate feasibility and inform the resources needed to scale-up drug checking services to reduce overdose risk.

Miniaturized paper-based analytical device for the portable analysis of phyto-cannabinoids in plant and oral fluids

In this work, a low-cost and eco-friendly paper-based analytical device (PAD) method is described for the determination of phyto-cannabinoids in cannabis and oral fluids based on a simple colorimetric reaction. The PAD was able to distinguish tetrahydrocannabinol (THC)- and cannabidiol (CBD)-rich plant samples by using 4-aminophenol (4-AP) and later on to quantify total phyto-cannabinoid content (THC + CBD + CBN) in plant and oral fluids by using the Fast Corinth V reagent. The chemical and physical properties regarding paper type and reagent concentration in the PAD were optimized to achieve the best analytical performance. After that, analytical features were obtained, including a linear range of 0.01–0.1 mg mL−1, a limit of detection (LOD) of 0.003 mg mL−1, and a suitable precision, expressed as relative standard deviation (RSD) lower than 10%. Furthermore, no significant interferences were observed in colorimetric reactions when tea, herbs, and drug samples were analyzed. Additionally, the PAD proved color stability up to 1 month after the sampling at 25 °C. The developed PAD was suitable for determining total phyto-cannabinoid content in plants and oral fluids, obtaining good results compared to GC–MS. Overall, this method showed good reliability resulting in an operational on-site device for drug monitoring.Graphical

Eco-Friendly Elaborated Clay-Supported Reduced Graphene Oxide for the Determination of Antibacterial Ciprofloxacin in Wastewater, Urine, and Drug Samples

The accumulation of pharmaceutical residues in the environment can indeed lead to a wide range of environmental problems which can have a negative impact on human health through various pathways. For this reason, it is of great importance to develop a rapid and sensitive strategy to monitor the accumulation of pharmaceutical residues, ultimately safeguarding both the environment and human health. In this article, the development of a carbon paste electrode modified by clay-supported reduced graphene oxide (rGO-Clay-CPE) is described. This sensor was used for the electrochemical detection of ciprofloxacin (Cipro). The rGO-Clay material was synthesized based on the thermal reduction of GO. Then, it was characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). Using differential pulse voltammetry (DPV), the prepared electrode shows high electrochemical performance towards the oxidation of Cipro. Under the optimized conditions, the DPV at the rGO-Clay sensor showed that the electro-analytical signal of Cipro is linearly related to the concentration in the range of 0.08–2.0–50.0 μM with a sensitivity of 11.24 μA μM−1 cm−2 and a limit of detection (LOD) of 7.7 nM. The developed sensor has successfully been applied for Cipro monitoring in wastewater, urine, and drug samples with acceptable outcomes.

Experimental study of the antibacterial efficacy of an antiseptic drug activated by ultrasound of different frequencies

Aim. To study the antibacterial efficacy of the antiseptic drug Miramistin, activated by ultrasound of different frequencies, against pathogenic microorganisms of periodontal pockets, in an experiment. Materials and methods. As an antiseptic drug, the drug Miramistin 0.01% was used, which was activated using ultrasound of different frequencies: high-frequency (880 kHz) in continuous mode for 4 minutes, low-frequency (26.5 kHz) in continuous mode for 2 minutes. To conduct the study, clinical strains of microorganisms obtained from periodontal pockets with moderate periodontitis were used: S. sanguis, S. pyogenes, P. intermedia, C. albicans. The study was carried out using automatic programmable cultivation, using the RTS-8 system. The studied samples of the antiseptic drug were previously diluted in a nutrient broth in a ratio of 2:200. Results. In the course of the study, it was found that with respect to pathogenic microorganisms obtained from periodontal pockets with moderate periodontitis, Miramistin in a dilution of 2:200, activated by low-frequency ultrasound, showed more pronounced antibacterial effect compared to Miramistin activated by high-frequency ultrasound. Conclusions. In the treatment of periodontitis, to suppress the vital activity of pathogenic microorganisms, preference should be given to the combined effects of low-frequency ultrasound and the antiseptic drug Miramistin.

CDS-DB, an omnibus for patient-derived gene expression signatures induced by cancer treatment.

Patient-derived gene expression signatures induced by cancer treatment, obtained from paired pre- and post-treatment clinical transcriptomes, can help reveal drug mechanisms of action (MOAs) in cancer patients and understand the molecular response mechanism of tumor sensitivity or resistance. Their integration and reuse may bring new insights. Paired pre- and post-treatment clinical transcriptomic data are rapidly accumulating. However, a lack of systematic collection makes data access, integration, and reuse challenging. We therefore present the Cancer Drug-induced gene expression Signature DataBase (CDS-DB). CDS-DB has collected 78 patient-derived, paired pre- and post-treatment transcriptomic source datasets with uniformly reprocessed expression profiles and manually curated metadata such as drug administration dosage, sampling time and location,and intrinsic drug response status. From these source datasets, 2012 patient-level gene perturbation signatures were obtained, covering 85 therapeutic regimens, 39 cancer subtypesand 3628 patient samples. Besides data browsing, downloadand search, CDS-DB also supports single signature analysis (including differential gene expression, functional enrichment, tumor microenvironmentand correlation analyses), signature comparative analysisand signature connectivity analysis. This provides insights into drug MOA and its heterogeneity in patients, drug resistance mechanisms, drug repositioningand drug (combination) discovery, etc. CDS-DB is available at http://cdsdb.ncpsb.org.cn/.

Oral Yol ile Alınan Alerji ve Kanser İlaçlarında Ağır Metallerin Tayini için Mikrodalga Çözünürleştirme Sistemi ile ICP-MS Analizi ve Validasyonu

The drug, one of the most important products that cannot be replaced in the field of health, prevents all threats to human health when used in place and dosage. Therefore, it has an important place in public health. Determination of the amounts and impurities of various elements used in drug production is an important parameter. According to the ICH Q3D(R1) international compliance conference guide, methods by which limit concentrations can be determined for elemental impurities by applying inductively coupled plasma (ICP) analysis to drugs are specified. In this study, the sample preparation step in the analysis of 23 elements in cancer and allergy drugs in tablet form was optimized by microwave digestion, and method development and validation studies were carried out for these drugs with inductively coupled plasma-mass spectrometry (ICP-MS). When the analysis results were evaluated, it was seen that the data obtained were by the limit values specified in the ICH. Detection and quantification limits of the developed method, and relative standard deviation values were determined, and recovery studies were carried out by adding standards at 4 different concentrations to determine the method's precision. The correlation coefficients obtained for heavy metals in this study ranged from 0.9993 to 1.000, while the detection limit was found to be between 0.001 and 1.756 µg/L. Thus, the reliability and precision of the validation study developed has been determined and it has been shown that this method can be used in similar drug samples.

Triboelectric nanogenerator-coated blade spray mass spectrometry for volume-limited drug analysis

The demand for analytical tools for the analysis of low-concentration volume-limited samples has driven researchers to explore new analytical approaches. Mass spectrometry excels at trace analysis due to its high sensitivity and specificity, whereas ambient methods simplify, or completely eliminate sample preparation. Herein, we report a triboelectric nanogenerator-coated blade spray ambient mass spectrometry (TENG-CBS MS) method for the extraction, elution, and ionization of volume-limited, low-concentration small molecule drug samples with minimum sample preparation. Using a TENG device as the CBS power supply, we show it is possible to extract and analyze drug samples in a pulsed fashion at sub-nanogram to picogram levels with good stability and reproducibility. A wide range of analytes polarities were tested. Results indicated this method could also be useful for the analysis of low-level analytes in precious, volume limited samples in a simple single step.