Utilizing experimental design and desirability function in optimizing RP-HPLC method for simultaneous determination of some skeletal muscle relaxants and analgesics

An experimental design and response surface methodologies using Plackett-Burman and Box-Behnken designs were applied for selecting and optimizing the most appropriate parameters which significantly affect the separation and quantitative estimation of five skeletal muscle relaxants and four analgesic drugs (baclofen, methocarbamol, dantrolene sodium, orphenadrine citrate, cyclobenzaprine hydrochloride, ketoprofen, etoricoxib, ibuprofen, and mefenamic acid) with a relatively short duration of analysis in a single run. For the separation of the nine drugs, an INERTSIL ODS-V3-5 µm C18 column (250 × 4.6 mm I.D.) was used with the optimum mobile phase conditions (45.15 mM ammonium acetate buffer pH 5.56 adjusted with acetic acid, acetonitrile, and methanol in a ratio of 30.5:29.5:40, v/v/v with a flow rate of 1.5 mL/min) and UV-detection at 220 nm. The optimized method was successfully subjected to the validation steps as described in ICH guidelines for linearity, precision, accuracy, robustness, and sensitivity. The optimized and validated method was effectively applied to determine the content of the studied drugs in their pharmaceutical preparations and to expand its applicability to the counterfeit estimation of etoricoxib in different brands of tablet dosage forms.

Facile immunochromatographic assay based on metal-organic framework-decorated polydopamine for the determination of hydrochlorothiazide adulteration in functional foods

Herein, a novel immunochromatographic assay (ICA) based on metal-organic framework-decorated polydopamine (MOF@PDA) was firstly developed for the determination of hydrochlorothiazide (HCTZ) adulteration in functional foods. The coupling rate of MOF@PDA carrier to HCTZ antibody was as high as 91.7 %. The detection limits of the developed MOF@PDA-ICA in functional tablets and capsules were 5.93 and 4.72 μg/kg, the linear ranges were 11.2-91.91 μg/kg and 9.11-86.78 μg/kg, respectively. The sensitivity was 27-fold higher than that of the reported ICA. The recovery was 82.5-116.6 %, and coefficient of variation was 6.9-14.2 %. The results can be achieved and analyzed in 8 min with the smartphone-based detection device. The parallel tests of 23 commercial functional tablets and capsules showed that the results of the MOF@PDA-ICA were consistent with that of the LC-MS/MS (R² > 0.99). Therefore, our method is facile, sensitive, portable, and can provide a reliable technical mean for the detection of HCTZ adulteration in functional foods.

Pesticides, trace elements and pharmaceuticals in tea samples available in Belgian retail shops and the risk associated upon acute and chronic exposure

Over the last decade, the consumption of tea and herbal tea has gained more and more popularity across the globe, but the potential presence of chemical contaminants (e.g. pesticides, trace elements, synthetic drugs) may raise health concerns. This study analysed selected teas available in Belgian retail stores and performed a risk assessment for these samples. No chemical adulteration could be detected in dry tea material. More than 38% of the dry leaves samples contained at least one pesticide exceeding the maximal residue level (MRL) set by the EU. However, further risk assessment, based on the values of pesticide residues and the toxic trace elements encountered in the brew, demonstrate that the consumption of these teas will not give rise to health concerns. Nonetheless, attention should be given to the leaching potential of nickel from teas and the presence of arsenic in brews from algae containing teas.

Thin Layer Chromatographic Method for Detection of Conventional Drug Adulterants in Herbal Products

Commercially available conventional drugs have been used to adulterate herbal products. Considering the rapid growth of herbal products’ market, it is essential to screen herbal products for the presence of conventional drugs. Simple analytical methods are needed for the rapid screening of conventional drugs that are likely to be adulterated in herbal products. Thin layer chromatography (TLC) methods for screening twelve conventional drugs in herbal products have been developed and applied. The analytes were extracted from herbal products using acetonitrile:methanol:acetic acid:water (4:4:1:1, v/v). Solvent mixture of dichloromethane:ethyl acetate:methanol (75:15:10, v/v) separated well trimethoprim, sildenafil, paracetamol, and sulfamethoxazole while pyrimethamine, metronidazole, and sulfadoxine were well separated by dichloromethane:ethyl acetate:methanol (77.5:12.5:10, v/v). In addition, acetyl salicylic acid, ibuprofen, diclofenac, quinine, and lumefantrine were well separated by ethyl acetate:methanol:30% ammonia (75:22.5:2.5, v/v). Chromatographic separations were found to be highly reproducible, and more than 10 samples can be analysed in one run. The method was applied in the screening of 229 herbal products. Consequently, 24.0% of the samples contained one adulterant, while 21.4% contained at least two adulterants. All conventional drugs detected in herbal products were not mentioned on the labels and therefore the consumers are kept unaware of their side effects and health problems. Further studies for confirming and quantitatively determining the adulterants in a wide range of products as well as a systematic toxicological analysis of the adulterants in herbal products are recommended.

DoE Screening and Optimization of Liquid Chromatographic Determination of Nicotinic Acid and Six Statins: Application to Pharmaceutical Preparations and Counterfeit Detection

An isocratic reversed-phase high performance liquid chromatographic method has been developed and validated to simultaneously determine nicotinic acid, pravastatin sodium, rosuvastatin calcium, atorvastatin calcium, pitavastatin calcium, lovastatin sodium and simvastatin sodium in focus on counterfeit drug detection. Thin-layer chromatography, nuclear magnetic resonance and mass spectrometry have been additionally performed to verify the identification of adulterants of counterfeit herbal medicines. Chromatographic separation was carried out on Inertsil® ODS-3 C18 (4.6 × 150 mm, 5 μm) with isocratic mobile phase elution containing a mixture of acetonitrile: methanol: 25 mM potassium dihydrogen phosphate buffer, pH 2.86 adjusted with 0.1 M o-phosphoric acid (48: 30: 22, v/v/v), at a flow rate of 1 mL/min and with UV detection at 238 nm. The design of experiment methodology, Plackett-Burman and Box-Behnken designs, was used to screen and optimize the mobile phase composition. The validation of the method was also carried out under the International Conference on Harmonization guidelines. The developed method was sensitive, accurate, simple, economical and highly robust, in addition to the comprehensiveness and novelty of this method for separating the seven drugs. The results were statistically compared with the reference methods used Student's t-test and variance ratio F-test at P < 0.05.

Recent Analytical Method for Detection of Chemical Adulterants in Herbal Medicine

Herbal medicine has become popular in recent years as an alternative medicine. The problem arises when herbal medicines contain an undeclared synthetic drug that is illegally added, since it is a natural product that does not contain any chemical drugs due to the potential cause of harmful effects. Supervision of herbal medicines is important to ensure that these herbal medicines are still safe to use. Thus, developing a reliable analytical technique for the determination of adulterated drugs in herbal medicine is gaining interest. This review aims to provide a recent analytical method that has been used within the past 5 years (2016-2021) for the determination of chemical adulterants in herbal medicine.

Chemical Barcoding: A Nuclear-Magnetic-Resonance-Based Approach To Ensure the Quality and Safety of Natural Ingredients

One of the greatest challenges facing the functional food and natural health product (NHP) industries is sourcing high-quality, functional, natural ingredients for their finished products. Unfortunately, the lack of ingredient standards, modernized analytical methodologies, and industry oversight creates the potential for low quality and, in some cases, deliberate adulteration of ingredients. By exploring a diverse library of NHPs provided by the independent certification organization ISURA, we demonstrated that nuclear magnetic resonance (NMR) spectroscopy provides an innovative solution to authenticate botanicals and warrant the quality and safety of processed foods and manufactured functional ingredients. Two-dimensional NMR experiments were shown to be a robust and reproducible approach to capture the content of complex chemical mixtures, while a binary normalization step allows for emphasizing the chemical diversity in each sample, and unsupervised statistical methodologies provide key advantages to classify, authenticate, and highlight the potential presence of additives and adulterants.

Yellow Oleander Seed, or "Codo de Fraile" (Thevetia spp.): A Review of Its Potential Toxicity as a Purported Weight-Loss Supplement

The Dietary Supplements and Health Education Act (DSHEA), passed by the United States Congress in October of 1994, defines herbal products as nutritional supplements, not medications. This opened the market for diverse products made from plants, including teas, extracts, essential oils, and syrups. Mexico and the United States share an extensive border, where diverse herbal products are available to the public without a medical prescription. Research undertaken in the neighboring cities of Ciudad Juarez, Mexico, and El Paso, Texas, USA, shows the use of herbs is higher in this border area compared to the rest of the United States. A portion of the population is still under the erroneous impression that "natural" products are completely safe to use and therefore lack side effects. We review the dangers of ingesting the toxic seed of Thevetia spp. (family Apocynaceae), commonly known as "yellow oleander" or "codo de fraile," misleadingly advertised on the Internet as an effective and safe dietary supplement for weight loss. Lack of proper quality control regarding herbs generates a great variability in the quantity and quality of the products' content. Herb-drug interactions occur between some herbal products and certain prescription pharmaceuticals. Certain herbs recently introduced into the U.S. market may not have been previously tested adequately for purity, safety, and efficacy. Due to the lack of reliable clinical data regarding the safe use of various herbal products currently available, the public should be made aware regarding the possible health hazards of using certain herbs for therapeutic purposes. The potentially fatal toxicity of yellow oleander seed is confirmed by cases reported from various countries, while the purported benefits of using it for weight loss have not been evaluated by any known clinical trials. For this reason, the use of yellow oleander seed as a dietary supplement should be avoided.