Drug Analytical Research

Quantitative estimation of drugs for erectile dysfunction and benign prostatic hyperplasia by high performance liquid chromatography: a review

Shalaka G. Gaonkar, Basavaraj M Dinnimath — Sat, 28 Dec 2024 00:00:00 -0300

This review article explores the critical application of High-Performance Liquid Chromatography (HPLC) in analyzing medications for Erectile Dysfunction (ED) and Benign Prostatic Hyperplasia (BPH). HPLC is essential for the precise measurement of these drugs, whether assessed individually or within combination therapies. The review thoroughly examines various HPLC methodologies, encompassing both single-drug and simultaneous analysis techniques. It addresses the optimization of HPLC conditions and validation practices necessary for achieving reliable results. Key challenges in HPLC analysis are highlighted, including sensitivity issues and the need for specific adjustments in analytical procedures. The article discusses the influence of factors such as column types, mobile phases, and detection methods on HPLC performance. It offers detailed insights into optimizing parameters to enhance resolution and accuracy, providing practical guidance for researchers working with ED and BPH drugs. Moreover, the review outlines best practices for validating HPLC methods according to regulatory standards, which are crucial for maintaining the quality and reproducibility of analytical results. It also identifies potential areas for improvement, including enhancing method sensitivity and reducing analysis time. By emphasizing the importance of HPLC in maintaining high analytical standards for ED and BPH drug analysis, this review serves as a valuable resource for researchers, clinicians, and pharmaceutical companies, ultimately aiming to enhance drug management and improve patient outcomes through better analytical practices and innovative approaches.

A short reflection addressed to the analysts about the relationship between mass spectrometry and sample preparation

Andreas S. L. Mendez, Matthew S. Halquist — Sat, 28 Dec 2024 00:00:00 -0300

Mass spectrometry is one of the most advanced technology applied to qualitative and quantitative analysis. The complexity related to this technique is not the only critical aspect to be considered in the routine of analysis. Actually the quality of analytical results is dependent on previous steps involved to the sample preparation, where well established protocols, conditions, solvents, dilutions, i.e. are crucial to have excellence in the analytical performance. All analysts involved must be qualified and recognize the importance of an integrative view about the sample, from different sources, complex or not, and the protocols to be applied sequentially in order to get prepared for a running through mass spectrometry or hyphenated system (LC-MS). In this work, through a simple and short reflection, the analysts are encouraged to reflect deeply about the importance of these two topics – mass spectrometry and sample preparation – to get excellence during the analytical routine.

Editorial

Drug Analytical Research — Sat, 28 Dec 2024 00:00:00 -0300

Chemical composition and antimycotic potential of basil, rosemary, clove and cinnamon essential oils against Trichophyton rubrum and Trichophyton mentagrophytes

Sat, 28 Dec 2024 00:00:00 -0300

Onychomycosis is a disease caused by fungi that affects the nails whose incidence is becoming increasingly frequent. The present study aimed the evaluation of the antifungal activity of essential oils from clove (Syzygium aromaticum), Chinese cinnamon (Cinnamomum cassia), rosemary (Rosmarinus officinalis) and basil (Ocimum basilicum), against the most prevalent dermatophytes implicated in onychomycosis: Trichophyton rubrum and Trichophyton mentagrophytes. The chemical composition of the oils was determined by GC-MS. The volatile oil of clove and Chinese cinnamon and basil presented, respectively, the phenylpropanoids eugenol (80.2%), E-cinnamaldehyde (99.4%) and methyl chavicol (68.81%) as the main components. The volatile oil of rosemary exhibited 1,8-cineole and camphor as the major compounds, representing 47% and 15% of the total content, respectively. The results obtained in broth microdilution tests indicate that basil oil presented the best antifungal potential against the tested strains of Trichophyton rubrum and Trichophyton mentagrophytes at concentrations that ranged from 8 mg/mL to 2 mg/mL. These findings point to the potential prospecting of Ocimum basilicum essential oil as a promising source of natural antimycotics to be subjected for further investigations.

Lean and eco-efficient method for evaluating the potency of tinidazole in tablets

Pollyanna Barbara Henrique, Ieda Sapateiro Torres, Ana Carolina Kogawa — Sat, 28 Dec 2024 00:00:00 -0300

Tinidazole (TIN), an amoebicide and giardicide, does not present microbiological methods in official compendia for evaluating the potency of final products. The objective of this work is to develop and validate an effective, lean and eco-efficient microbiological turbidimetric method by National Environmental Method Index (NEMI) and Eco-Scale Assessment (ESA) to evaluate the potency of TIN-based tablets. The microbiological method was performed using Escherichia coli ATCC 25922 at 1 % in BHI broth, TIN solution in purified water and ethanol (90:10, v/v) at concentrations of 40, 60 and 90 μg mL^-1, shaker at 80 rpm, 4 hours of incubation, quartz cuvette and 530 nm. The method was linear from 40 to 90 μg mL^-1with a correlation coefficient of 0.9991, selective, precise (RSD < 4 %), accurate with 99.65 % recovery and robust to changes in culture medium volume, culture medium brand, inoculum percentage and shaker rotation speed. The potency of TIN tablets was 98.50 %. The greenness of the method was evaluated and NEMI presented 3 green quadrants and the ESA score was 93, showing an excellent green analysis option. This work presents a lean and eco-efficient proposal for evaluating the potency of TIN tablets for chemical-pharmaceutical laboratories around the world.

Validated HPLC Methodology for Pregabalin Quantification in Human Urine Using 1-Fluoro-2,4-dinitrobenzene Derivatization

Sat, 28 Dec 2024 00:00:00 -0300

Pregabalin (PGB) is a synthetic drug used for the treatment of central nervous system disorders and neuropathic pain. PGB is metabolized to N-Methyl pregabalin while the rest is excreted virtually unchanged in the urine. Numerous analytical techniques for measuring pregabalin have been documented. This study aimed to validate a simple, sensitive, and accurate method for PGB quantification in human urine using the HPLC technique with 1-Fluoro-2, 4-dinitrobenzene used as a derivatizing agent. One hundred and twenty urine samples were analyzed by a reversed-phase (C18) column and a mixture of acetonitrile and 50 mM KH2PO4 (pH 2.5) (60:40, v/v) as mobile phase and the flow rate was 1 ml/min and the UV detector wavelength was set to 360nm. The procedure was linear within the 10-1000 μg/ml range of PGB in urine (r > 0.99). Intraday and interday RSD precision values fell between 2.8% and 5.9%. 2.5 and 1.5 μg/ml, respectively, were determined to be the method's limits of quantification and detection. The recovery (90.8%) and statistical characteristics show that the suggested method has excellent accuracy and precision. The method is accurate, precise, reproducible, and specific, and it can be applied to regular examinations of pregabalin in urine samples.

Photodegradation kinetics of Bilastine in tablets

Sat, 28 Dec 2024 00:00:00 -0300

Photodegradation is the process by which a chemical substance is broken down through exposure to light, typically ultraviolet (UV) radiation. This process is significant in environmental chemistry, where sunlight can degrade pollutants and materials, influencing their persistence and toxicity. Bilastine is a novel non-sedating histamine H1-receptor antagonist developed for the treatment of allergic rhino conjunctivitis and urticaria. The literature presents some studies on the quantitative determination of bilastine by high-performance liquid chromatography in pharmaceutical forms and biological fluids, however, no data on the photodegradation kinetics of this drug are described. Therefore, the objective of the study was to determine the photodegradation kinetics of the drug bilastine in coated tablets using a liquid chromatography method previously developed and validated by the same research group (unplished data). The study was carried out with methanolic solution containing 100.0 mg mL^-1 of bilastine drug product exposed to UV-C radiation (254 nm). The irradiation of the samples was done at pre-established times: 0, 15, 30, 60, 120 and 180 minutes. The chromatographic separation was performed in a Shim-pack^® RP-18 column; the mobile phase comprising a mixture of 0.3% triethylamine (pH adjusted to 6.0 with 20% formic acid) and acetonitrile (66:34, v/v) at a flow-rate of 1.0 mL min^-1with isocratic elution. The temperature was set at 25 °C in the column oven. Bilastine was determined by UV detection at 207 nm using photodiode-array. The results demonstrated that the photodegradation kinetics of bilastine in methanolic solution follows the first order of reaction, with a t_90% of 27.11 minutes and degradation rate constant (k) of 0.0007 min^-1.

Systematic study of drug distribution profiles of different nanocarriers in the skin layers: a more accurate and targeted delivery

Sat, 28 Dec 2024 00:00:00 -0300

The aim of this work was to evaluate the skin distributions of two drugs with different logarithm of the distribution coefficient (Log D) values. Melatonin (MEL; Log D 1.74) and benzophenone-3 (BZA-3; Log D 3.88) lipid core nanocapsules (LNCs) were prepared with poly(e-caprolactone) (PCL) of different molar weights (14,000 g mol^-1and 80,000 g mol^-1), capric/caprylic triglyceride, sorbitan monostearate and polysorbate 80, and nanoemulsions (NE) were similarly prepared without polymer. In vitro release experiments combined with in vitro percutaneous penetration/permeation data demonstrated that the localization of the substance in the nanoparticles (determined by Log D) is crucial for understanding their diffusion behavior. The results demonstrated that substances of moderate lipophilicity, such as MEL, are affected by the molar mass of the polymer since the use of 80,000 g mol^-1 PCL in the particle composition (LNC80MEL) guaranteed a greater encapsulation efficiency (EE%) (55%). On the other hand, the percutaneous distribution profile of substances with high lipophilicity, such as BZA-3, is not influenced by the molar mass of the polymer since for all formulations containing BZA-3, the EE% was approximately 99%. However, the presence of a polymer in the nanocapsule (LNC) tends to promote greater retention of the substance at the stratum corneum level, while its absence (NE) allows penetration of the particle through the skin layers and drives a higher concentration of BZA-3 into the dermis.