Journal of AOAC International最新文献

Background: Computationally designed molecular imprinted polymer (MIP) incorporation into electrochemical sensors has many advantages to the performance of the designed sensors. The innovative self-validated ensemble modeling (SVEM) approach is a smart machine learning-based (ML) technique that enables the design of more accurate predictive models using smaller data sets.

Objective: The novel SVEM experimental design methodology is exploited here exclusively to optimize the composition of four eco-friendly PVC membranes augmented by a computationally designed magnetic molecularly imprinted polymer to quantitatively determine drotaverine hydrochloride (DVN) in its combined dosage form and human plasma. Furthermore, the application of hybrid computational simulations such as molecular dynamics and quantum mechanical calculations (MD/QM) is a time-saving and eco-friendly provider for the tailored design of the MIP particles.

Method: Here, for the first time, the predictive power of ML is assembled with computational simulations to develop four PVC-based sensors decorated by computationally designed MIP particles using four different experimental designs known as central composite, SVEM-LASSO, SVEM-FWD, and SVEM-PFWD. The pioneering AGREE approach further assessed the greenness of the analytical methods, proving their eco-friendliness.

Results: The proposed sensors showed decent Nernstian responses toward DVN in the range of 58.60-59.09 mV/decade with a linear quantitative range of 1 × 10-7 - 1 × 10-2 M and limits of detection in the range of 9.55 × 10-8 to 7.08 × 10-8 M. Moreover, the proposed sensors showed ultimate eco-friendliness and selectivity for their target in its combined dosage form and spiked human plasma.

Conclusions: The proposed sensors were validated in accordance with International Union of Pure and Applied Chemistry (IUPAC) recommendations, proving their sensitivity and selectivity for drotaverine determination in dosage form and human plasma.

Highlights: This work presents the first ever application of both the innovative SVEM designs and MD/QM simulations in the optimization and fabrication of drotaverine-sensitive and selective MIP-decorated PVC sensors.

Background: Cimicifugae Rhizoma, known in Chinese as Shengma, is a common medicinal material in traditional Chinese medicine (TCM), mainly used for treating wind-heat headaches, sore throat, uterine prolapse, and other diseases.

Objectives: An approach using a combination of ultra-performance liquid chromatography (UPLC), MS, and multivariate chemometric methods was designed to assess the quality of Cimicifugae Rhizoma.

Methods: All materials were crushed into powder and the powdered sample was dissolved in 70% aqueous methanol for sonication. Chemometric methods, including hierarchical cluster analysis (HCA), principal component analysis (PCA), and orthogonal partial least-squares discriminant analysis (OPLS-DA), were adopted to classify and perform a comprehensive visualization study of Cimicifugae Rhizoma. The unsupervised recognition models of HCA and PCA obtained a preliminary classification and provided a basis for classification. In addition, we constructed a supervised OPLS-DA model and established a prediction set to further validate the explanatory power of the model for the variables and unknown samples.

Results: Exploratory research found that the samples were divided into two groups, and the differences were related to appearance traits. The correct classification of the prediction set also demonstrated a strong predictive ability of the models for new samples. Subsequently, six chemical makers were characterized by UPLC-Q-Orbitrap-MS/MS, and the content of four components was determined. The results of the content determination revealed the distribution of representative chemical markers caffeic acid, ferulic acid, isoferulic acid, and cimifugin in two classes of samples.

Conclusions: This strategy can provide a reference for assessing the quality of Cimicifugae Rhizoma, which is significant for the clinical practice and QC of Cimicifugae Rhizoma.

Highlights: The HCA, PCA and OPLS-DA models visually classify Cimicifugae Rhizoma by appearance traits and obtain the chemical markers that influence the classification. The training and prediction sets were built to demonstrate the accuracy of the classification. Advanced UPLC-Q-Orbitrap-MS/MS technology provides powerful elucidation of critical chemical markers.

Background: Accurate, high-confidence data is critical for assessing potential biothreat incidents. In a biothreat event, false-negative and -positive results have serious consequences. Worst case scenarios can result in unnecessary shutdowns or fatalities at an exorbitant monetary and psychological cost, respectively. Quantitative PCR assays for agents of interest have been successfully used for routine biosurveillance. Recently, there has been increased impetus for adoption of amplicon sequencing (AS) for biosurveillance because it enables discrimination of true positives from near-neighbor false positives, as well as broad, simultaneous detection of many targets in many pathogens in a high-throughput scheme. However, the high sensitivity of AS can lead to false positives. Appropriate controls and workflow reporting can help address these challenges.

Objectives: Data reporting standards are critical to data trustworthiness. The standards presented herein aim to provide a framework for method quality assessment in biodetection.

Methods: We present a set of standards, Amplicon Sequencing Minimal Information (ASqMI), developed under the auspices of the AOAC INTERNATIONAL Stakeholder Program on Agent Detection Assays for making actionable calls in biosurveillance applications. In addition to the first minimum information guidelines for AS, we provide a controls checklist and scoring scheme to assure AS run quality and assess potential sample contamination.

Results: Adoption of the ASqMI guidelines will improve data quality, help track workflow performance, and ultimately provide decision makers confidence to trust the results of this new and powerful technology.

Conclusion: AS workflows can provide robust, confident calls for biodetection; however, due diligence in reporting and controls are needed. The ASqMI guideline is the first AS minimum reporting guidance document that also provides the means for end users to evaluate their workflows to improve confidence.

Highlights: Standardized reporting guidance for actionable calls is critical to ensuring trustworthy data.

Background: Spectrophotometric resolution of a mixture of several drugs is considered a cheaper, simpler, and more versatile alternative compared to costly chromatographic instruments.

Objective: The work aims to resolve the interfering spectra of ephedrine hydrochloride, naphazoline nitrate, and methylparaben in nasal preparations using smart spectrophotometric methods.

Method: In our work, derivative and dual-wavelength methods were combined to eliminate this interference, under the name of derivative dual-wavelength method. Other methods, namely successive derivative subtraction and chemometric analysis, were also able to eliminate this interference. The methods have proven their applicability as they follow the International Conference on Harmonization (ICH) requirements regarding repeatability, precision, accuracy, selectivity, and linearity. Eco-scale, GAPI, and AGREE tools were used to estimate the possible environmental effects of the methods.

Results: Acceptable results for repeatability, precision, accuracy, selectivity, and linearity were obtained. Limit of detection (LOD) values were 2.2 for ephedrine and 0.3 for naphazoline. The correlation coefficients were above 0.999. The methods were proven to be safe for application.

Conclusions: The introduced methods are cheap and easily implemented compared to chromatographic techniques. They can be used in purity-checking of raw material and estimation of concentrations in market formulations. The replacement of the published chromatographic techniques with our developed methods is useful when needing to save money, effort, and time.

Highlights: The three components of a decongestant nasal preparation were determined using cheap, green, and versatile spectrophotometric methods that keep the advantages of chromatographic techniques, including accuracy, reproducibility, and selectivity.

Background: Linezolid (LNZ) is extremely prone to resistance. The development of resistance to LNZ should be taken into consideration when selecting this drug as a therapeutic option. It is well established that reactive oxygen species (ROS) generated by iron oxide nanoparticles (MNPs) could kill the infecting bacteria. So, we hypothesized the synergistic antibacterial effect of iron oxide nanoparticles and LNZ.

Objective: To study the release and antibacterial effects of LNZ-loaded superparamagnetic iron oxide nanoparticles (SPIONs) on Staphylococcus aureus and Streptococcus pneumoniae.

Method: Ferrofluid containing SPIONs was synthesized via chemical co-precipitation method and stabilized by sodium lauryl sulphate (SLS). SPIONs were then loaded with LNZ and characterized for particle size, FT-IR, XRD, and entrapment efficiency. Further antibacterial activity of SPIONs and LNZ-loaded SPIONs was investigated. For the in vitro release findings, HPLC analytical method development and validation were performed.

Results: Isolation of LNZ was accomplished on a C-18 column with methanol-TBHS (tetra butyl ammonium hydrogen sulphate, 50:50, v/v). The eluate was monitored at 247 nm with a retention time of 4.175 min. The MNP's DLS measurement revealed monodispersed particles with an average size of 16.81 ± 1.07 nm and PDI 0.176 ± 0.012. In optimized formulation, 25 ± 1.75% (w/w) of the drug was found to be entrapped. XRD revealed uniform coating of oleic acid covering the entire magnetic particles' surface with no change in its crystallinity. An effective antimicrobial activity was observed at the lowered dose of drug.

Conclusions: A robust HPLC method was developed to quantify the LNZ in MNPs, and outcomes showed that the reduced dose of LNZ incorporated in SPIONs was able to show similar activity as the marketed product.

Highlights: Successfully reduction of the dose of LNZ was established with the aid of biocompatible MNPs to attain the equivalent antibacterial activity.

Background: Flibanserin (FLB) was first synthesized as an antidepressant drug; however, due to its enhancing effects on sexual activity, it was approved for treatment of hypoactive sexual desire disorder in women in 2015.

Objective: The aim of this study was to develop a new and fully validated HPLC method for analysis of FLB in pharmaceutical formulations besides its degradation products, and identification of possible formation mechanisms by using HPLC-DAD-ESI-IT-TOF-MSn.

Method: The HPLC separation was achieved in a Supelco Ascentis® Express series phenyl hexyl column (100 × 4.6 mm, ID 2.7 µm). The mobile phase was acetonitrile-ammonium acetate solution (50:50, v/v, 10 mM, pH 5.4) mixture, which was pumped at the rate of 0.5 mL/min. Chromatography, detection, and structural identification was performed by using a LCMS-IT-TOF instrument (Shimadzu, Japan).

Results: 1-(2-(4-(3-hydroxy-5-(trifluoromethyl)phenyl)piperazine-1-yl)ethyl)-1,3-dihydro-2H-benzo[d]imidazol-2-one is proposed as a novel degradation product, with a mass of 407.1695 and a formula of C20H21F3N4O2 with a margin of error about 0.001 ppm. The developed method is applicable with 98% accuracy within the 2.5-50.0 µg/mL range. The LOD and LOQ were about 500 ng/mL and 1.50 µg/mL, respectively. The transferability and variation between laboratories were tested by inter-laboratory comparison and evaluated with one-way analysis of variance.

Conclusions: A novel FLB degradation product, which was produced under oxidative forced degradation conditions was observed and identified for the first time; in addition, the formation kinetics of the degradation product besides decomposition of FLB was studied. Furthermore, an inter-laboratory comparison was carried out, and application of the proposed method on a pseudo Addyi® (Sprout Pharmaceuticals, Inc.) sample was tested using both instrument configurations.

Highlights: A novel stability-indicating assay method was developed and fully validated according to the International Council on Harmonization (Q2) R1 for the analysis of FLB in the pharmaceutical preparations. A new degradation product was identified in the oxidative forced degradation condition and characterized using HPLC-DAD-ESI-IT-TOF-MS3. Moreover, the possible mechanism and the formation kinetic of the degradation product were revealed. In addition, the developed method was transferred to another LC-PDA instrument for inter-laboratory comparison. Finally, the current method was applied to a pseudo formulation of Addy in both instruments, and ANOVA was applied for evaluation.

Background: Due to its medicinal properties, Pistacia integerrima is in high demand and is extensively used as a key ingredient in various formulations. However, its popularity has led to its inclusion on the International Union for Conservation of Nature threatened category list. In Ayurvedic texts, such as Bhaishajaya Ratnavali, Quercus infectoria is recommended as a substitute for P. integerrima in different formulations. Additionally, Yogratnakar highlights that Terminalia chebula shares similar therapeutic properties with P. integerrima.

Objective: The objective of the current study was to gather scientific data on metabolite profiling and marker-based comparative analysis of Q. infectoria, T. chebula, and P. integerrima.

Methods: In present study, hydroalcoholic and aqueous extracts of all three plants were prepared and standardized for the comparative evaluation of secondary metabolites. TLC was carried out for the comparative fingerprinting of the extracts using chloroform-methanol-glacial acetic acid-water (60 + 8 + 32 + 10, by volume) as a solvent system. A fast, sensitive, selective, and robust HPLC method was developed to determine gallic acid and ellagic acid from both extracts of all three plants. The method was validated for precision, robustness, accuracy, LOD and LOQ as per the International Conference on Harmonization guidelines.

Results: The TLC analysis revealed the presence of several metabolites, and the pattern of metabolites in the plants exhibited a certain degree of similarity. A highly precise and reliable quantification technique was created for gallic acid and ellagic acid, operating within a linear concentration range of 81.18-288.22 µg/mL and 3.83-13.66 µg/mL, respectively. The correlation coefficients for gallic acid and ellagic acid were 0.997 and 0.996, indicating good linear relationships. The gallic acid content in all three plants ranged from 3.74 to 10.16% w/w, while the ellagic acid content ranged from 0.10 to 1.24% w/w.

Conclusion: The study contributes to the scientific understanding of the metabolite profiles and comparative analysis of Q. infectoria, T. chebula, and P. integerrima. The findings provide valuable insights into the chemical composition of these plants and can be used for various applications in herbal medicine.

Highlights: This pioneering scientific approach highlights the phytochemical similarities between Q. infectoria, T. chebula and P. integerrima.

Background: Nebivolol and valsartan (VAL) in combination with each other successfully control blood pressure and improve hypertension patient outcomes.

Objective: To develop and validate innovative, simple, and sustainable spectrophotometric methods for the simultaneous analysis of nebivolol and valsartan.

Method: The new modified difference amplitude modulation (MD-AM) method uses only unified regression equation and does not require any resolution techniques. Other different approaches were also applied for the determination of the same mixture including univariate and multivariate spectrophotometric methods. The multivariate methods were PLS and PCR, whereas the univariate methods were derivative ratio (DD1), ratio difference (RD), constant center (CC), constant center spectrum subtraction (CC-SS), constant value coupled with amplitude difference (CV-AD), advanced concentration value (ACV), and amplitude difference (AD). The proposed methods use a green solvent; thus, the environmental impact of the presented procedures was evaluated qualitatively and quantitatively using six well-known evaluation tools.

Results: All methods were applied successfully for the analysis of the studied drugs in their bulk powder, pharmaceutical dosage form Byvalson®, and in vitro release at intestinal pH (7.4) using a USP dissolution tester. Results obtained were compared statistically with the reported method and with each other using a one-way ANOVA statistical test, and no significant differences were found.

Conclusions: All green and white analytical chemistry evaluation tools results confirm the safety, sustainability, and cost-effectiveness of the approaches, indicating that the methods are regarded green and sustainable. Results were agreeable, encouraging their applicability in quality control laboratories for dosage form and making these methods an eco-friendly substitute for the analysis of this combined dosage form and for evaluating the dissolution profile.

Highlights: For the first time, a severely overlapped spectrum was determined using a unified regression equation without the need of extended part or zero contribution regions by the novel method MD-AM. The proposed methods are the first study of in vitro dissolution profiling of nebivolol hydrochloride (NEB) and VAL and the first sustainable and green methods applied without compromising the analytical criteria.