From Gut Microbiomes to Infectious Pathogens: Neurological Disease Game Changers.

Gut microbiota and infectious diseases affect neurological disorders, brain development, and function. Compounds generated in the gastrointestinal system by gut microbiota and infectious pathogens may mediate gut-brain interactions, which may circulate throughout the body and spread to numerous organs, including the brain. Studies shown that gut bacteria and disease-causing organisms may pass molecular signals to the brain, affecting neurological function, neurodevelopment, and neurodegenerative diseases. This article discusses microorganism-producing metabolites with neuromodulator activity, signaling routes from microbial flora to the brain, and the potential direct effects of gut bacteria and infectious pathogens on brain cells. The review also considered the neurological aspects of infectious diseases. The infectious diseases affecting neurological functions and the disease modifications have been discussed thoroughly. Recent discoveries and unique insights in this perspective need further validation. Research on the complex molecular interactions between gut bacteria, infectious pathogens, and the CNS provides valuable insights into the pathogenesis of neurodegenerative, behavioral, and psychiatric illnesses. This study may provide insights into advanced drug discovery processes for neurological disorders by considering the influence of microbial communities inside the human body.

Green HPLC Method for Simultaneous Analysis of Three Natural Antioxidants by Analytical Quality by Design.

BACKGROUND: Glutathione, silybin, and curcumin are well-known potential antioxidants that are recommended as adjuvant therapy in cancer treatment. OBJECTIVE: Based on the principles of Analytical Quality by Design (AQbD) and green analytical chemistry, a simple, robust, and environmentally benign HPLC method for the simultaneous estimation of glutathione, silybin, and curcumin in bulk and formulation was performed. METHOD: Elution was achieved by an Agilent Eclipse XDB C18 (150 mm × 4.6 mm id, 3.5 µm) column using a gradient mobile phase composed of ethanol-water pH 6.7 (with 0.1%, v/v orthophosphoric acid) and 1.07 mL/min flow rate with PDA detection at 215 nm. Critical method variables were identified by risk assessment using an Ishikawa diagram, and multivariate optimization of the experimental conditions for the HPLC technique was accomplished by central composite design using design of experiments (DoE) software. RESULTS: The separation was achieved within 15 min, where the retention time of glutathione, silybin, and curcumin were 3.3, 4.9, and 7.3 min, respectively. The standard curve was linear in the range of 3.75-26.25 µg/mL for glutathione, 62.50-437.50 µg/mL for silybin, and 12.5-87.50 µg/mL for curcumin. The developed method was validated as per ICH guidelines Q2 (R1), and all the parameters are within specified limits. CONCLUSIONS: The proposed method is simple, precise, and robust, which can be employed for routine analysis and also concluded to be a greener approach according to AGREE, Green Analytical Procedure Index, and analytical eco-scale tools. HIGHLIGHTS: The chosen antioxidants were evaluated for the very first time simultaneously using the chromatographic technique in bulk and dosage forms employing green solvents. The peak purity of all three compounds was studied using a PDA detector. Wastage was reduced in terms of time, cost, and solvents by employing AQbD elements and tools. Complete application of environmentally sustainable safe solvents were employed.

Characterization, quantification and a multi-computational in silico toxicity assessment of impurity (feruloyl methane) in synthetic curcumin using RP-HPLC-UV technique.

Feruloyl Methane (FM) is a common impurity in Synthetic Curcumin (SC) that affects its purity and potency. The identification and quantification of FM is crucial to ensure the quality and safety of SC based drugs. The current study aims to develop and validate a simple, rapid and cost-effective analytical technique for the precise and accurate quantification of FM in SC using RP-HPLC with a UV-Vis detector (Ultraviolet/Visible) and assessment of its toxicity by multi-computational methods. The developed HPLC method with a UV-Vis detector enabled accurate identification and quantification of FM in SC. The optimized method was validated in accordance with ICH guidelines Q2(R1) and all parameters were found to be within the standard acceptance range. The ideal run time was determined to be 10 min and the impurity eluting at a retention time of 2.65 min was characterized using spectral techniques viz., mass spectrometry, FTIR and 1 H NMR, confirming the presence of FM. The amount of FM in SC was estimated to be 8.26 µg/kg. In addition, toxicity assessments using in silico tools such as ProTox- II, ADMETlab 2.0 and PASS Online indicated that the presence of FM in SC is not safe for human consumption. In conclusion, the developed method is not only capable of quantifying FM but also aids in distinguishing Natural Curcumin (NC) adulterated with SC and can be applied to a wide range of fields such as natural drug analysis, food analysis and toxicity prediction.

Nitrosamine Impurities in Herbal Formulations: A Review of Risks and Mitigation Strategies.

Nitrosamines are a class of chemical compounds that have been found to be impurities in a variety of pharmaceutical products. These impurities have raised concerns due to their potential carcinogenic effects. Recent studies have identified nitrosamines as impurities in a number of pharmaceutical products including angiotensin II receptor blockers (ARBs) and proton pump inhibitors (PPIs). The presence of nitrosamines in these products has led to recalls and market withdrawals. In addition to pharmaceuticals, nitrosamines have also been found in some herbal medicines particularly those containing traditional Chinese medicinal ingredients. The presence of nitrosamines in herbal formulations poses a significant risk to public health and highlights the need for quality control and regulations in the herbal drug industry. The present review article aims to discuss nitrosamine impurities (NMI) prominent causes, risks and scientific strategies for preventing NMI in herbal formulations. The primary objective of this study is to examine the origins of nitrosamine contamination in herbal formulations, the risks associated with these contaminants, and the methods for reducing them. The significance of thorough testing and examination before releasing herbal products to the public is also emphasized. In conclusion, the presence of nitrosamines is not limited to pharmaceutical products and poses a significant threat to the safety of herbal drugs as well. Adequate testing and extensive research are crucial for producing and distributing herbal medicines to the general population.

Quantification of rosiglitazone in rat plasma and tissues via LC-MS/MS: Method development, validation, and application in pharmacokinetic and tissue distribution studies.

A bioanalytical method for the quantification of rosiglitazone in rat plasma and tissues (adipose tissue, heart, brain, bone, and kidney) using LC-MS/MS was developed and validated. Chromatographic separation was achieved on a Gemini C18 column (50 × 4.6 mm, 3 µm) using a mobile phase consisting of 10 mM ammonium formate (pH 4.0) and acetonitrile (10:90, v/v) at a flow rate of 0.8 mL/min and injection volume of 10 µL (internal standard: pioglitazone). LC-MS detection was performed with multiple reaction monitoring mode using target ions at m/z → 358.0 and m/z → 357.67 for rosiglitazone and pioglitazone (internal standard), respectively. The calibration curve showed a good correlation coefficient (r2 ) over the concentration range of 1-10,000 ng/mL. The mean percentage recoveries of rosiglitazone were found to be over the range of 92.54-96.64%, with detection and lower quantification limit of 0.6 and 1.0 ng/mL, respectively. The developed method was validated per U.S. Food and Drug Administration guidelines and successfully utilized to measure rosiglitazone in plasma and tissue samples. Further, the developed method can be utilized for validating specific organ-targeting delivery systems of rosiglitazone in addition to conventional dosage forms.

Simultaneous quantification of oxcarbazepine and its active metabolite in spiked human plasma using ultra performance liquid chromatography-MS/MS.

Aim: Clinical monitoring of oxcarbazepine (OXC) and its metabolite licarbazepine (MHD) in biological matrix requires a sensitive and validated analytical method. The aim of this study is to develop and validate an optimized ultra performance liquid chromatography-MS/MS based bioanalytical method for the simultaneous estimation of OXC and its metabolite MHD in human plasma, using deuterated internal standard method. Materials & methods: A reverse phase ultra performance liquid chromatography analysis and mass spectrometric detection was performed using electrospray ionization in positive ion mode as interface, multiple reaction monitoring as mode of acquisition. Results & conclusion: The linearity range was 10-4011 ng/ml for OXC and 40-16061 ng/ml for MHD. The kinetic parameters were calculated and compared for bioequivalence. This method fulfilled the validation guidelines, could be employed for determining bioavailability and in new formulation development studies.

Beta-Alanine and Tris-(hydroxyl methyl) Aminomethane as Peak Modifiers in the Development of RP-HPLC Methods Using Aceclofenac and Haloperidol Hydrochloride as Exemplar Drugs.

In the present analytical approach, beta-alanine (ALA) and tris-(hydroxyl methyl) aminomethane (TRIS) were investigated as peak modifiers due to their water solubility and their possible peak modifying a property. These reagents were tested for their efficacy on the elution of aceclofenac (ACF) and haloperidol hydrochloride (HLC) from C18 column (250 mm × 4.6 mm, 5 µ) equipped with a photodiode array detector. The test reagents were investigated at 0.25 ± 0.05% concentration with a varying % aqueous composition on elution efficacy of HLC and ACF. The added ALA/TRIS in the mobile phase significantly (P < 0.05) improvised the symmetrical elution of HLC with 3-fold theoretical plates increase (P < 0.05) and 10-fold reduced capacity factor as compared to the control run. For ACF, the shoulder effect observed for ACF peak was eliminated. The optimized mobile phase was a combination of acetonitrile and water containing 0.25% beta-alanine/TRIS (pH 3.5 with ortho-phosphoric acid) at the ratio of 70:30 and 60:40% v/v, respectively, for ACF and HLC. The method was validated as per ICHQ2 guidelines. The column performance was tested for reproducibility in non-peak modifier applications and revealed a null effect on the column, thus these agents are relatively less toxic to HPLC columns.

Characterization of the Oxidative Degradation Product of Darunavir by LC-MS/MS.

A rapid, selective, and reliable LC-MS(n) method has been developed and validated for the isolation and structural characterization of the degradation product of darunavir (DRV). DRV, an HIV-1 protease inhibitor, was subjected to intrinsic oxidative stress conditions using 30% hydrogen peroxide and the degradation profile was studied. The oxidative degradation of DRV resulted in one degradation product. The unknown degradation product was separated on a Hibar Purospher C18 (250 mm × 4.6 mm; 5 µm) column by using 0.01 M ammonium formate (pH 3.0) and acetonitrile as mobile phase in the ratio of 50:50, v/v. The eluents were monitored at 263 nm using a UV detector. The isolated degradation product was characterized by UPLC-Q-TOF and its fragmentation pathway was proposed. The proposed structure of the degradation product was confirmed by HRMS analysis. The developed stability-indicating LC method was validated with respect to accuracy, precision, specificity/selectivity, and linearity. No prior reports were found in the literature about the oxidative degradation behavior of DRV.