Stability-Indicating Analytical Approach for Stability Evaluation of Lactoferrin.

Lactoferrin is a multifunctional iron-binding glycoprotein in milk. Due to its potential for the treatment of various diseases, interest in products containing lactoferrin is increasing. However, as a protein, it is prone to degradation, which critically affects the quality of products.

Comprehensive Stability Study of Vitamin D3 in Aqueous Solutions and Liquid Commercial Products.

Vitamin D3 has numerous beneficial effects, such as musculoskeletal, immunomodulatory, and neuroprotective. However, its instability is the main obstacle to formulating quality products. Despite increased attention and growing use, data on vitamin D3 stability is scarce because data from individual studies is inconclusive and mostly qualitative.

Stability of Reduced and Oxidized Coenzyme Q10 in Finished Products.

The efficiency of coenzyme Q10 (CoQ10) supplements is closely associated with its content and stability in finished products. This study aimed to provide evidence-based information on the quality and stability of CoQ10 in dietary supplements and medicines. Therefore, ubiquinol, ubiquinone, and total CoQ10 contents were determined by a validated HPLC-UV method in 11 commercial products with defined or undefined CoQ10 form.

Retinoid stability and degradation kinetics in commercial cosmetic products.

Background: Retinoids as dermatological agents are effective against acne, psoriasis, skin aging, and other skin conditions. However, their susceptibility to degradation is a limiting factor for their widespread use.

Objectives: Within this study, we aimed to provide comprehensive and evidence-based information on retinoid stability and degradation kinetics in commercial cosmetics, focusing on different factors affecting their stability.

Prediction of fasted and fed bioequivalence for immediate release drug products using physiologically based biopharmaceutics modeling (PBBM).

Bioequivalence studies are an integral part of clinical pharmacology strategy for drug development. Physiologically based biopharmaceutics modeling (PBBM) can be a helpful tool to assess potential bioequivalence risks and predict the outcome of bioequivalence studies. In this study, GastroPlus™ was used for virtual bioequivalence (VBE) assessment of 6 case studies which includes four BCS 2, and one each of BCS 1 and 3 molecules.

Quantification of reduced and oxidized coenzyme Q10 in supplements and medicines by HPLC-UV.

Coenzyme Q10 (CoQ10) supplements are widely used because of their antioxidant and anti-inflammatory effects, especially in the management of cardiovascular diseases. The latest pharmaceutical approach to increase CoQ10 bioavailability and efficiency is the formulation of its reduced form. Regardless of the growing number and usage of CoQ10 preparations, their analytics and quality control is inadequate, neglecting interconversion between the two CoQ10 forms.

Quality control of retinoids in commercial cosmetic products.

Background: Retinoids are widely used in different cosmetic products because of general improvement of skin appearance. However, retinoid concentration in cosmetics is restricted, and one particular form-retinoic acid, is banned in cosmetics due to safety reasons.

Aims: Within this study, we aimed to examine the quality of a considerable number of commercial retinoid cosmetic products in terms of their content and labeling, including also screening for the presence of retinoic acid.

A review of methods for solubility determination in biopharmaceutical drug characterization.

The significance of thermodynamic solubility in biopharmaceutical compound or drug characterization as well as the importance of having methods that accurately establish it have been extensively addressed. Nonetheless, its precise determination continues to remain a challenging task to accomplish. Even more so when the number of compounds to evaluate is high and the available amount of each compound is low, both of which are inevitable for the compound characterization during the drug development process.

Fast and Simple LC-MS/MS Method for Rifampicin Quantification in Human Plasma.

A simple, fast, and cost-effective LC-MS/MS method for quantification of rifampicin in human plasma was developed and fully validated. The plasma samples containing rifampicin and isotopically labelled internal standard rifampicin D8, were cleaned up using a Captiva ND Lipids filtration plate. Chromatographic separation was achieved on an 1290 Infinity liquid chromatograph coupled to 6460 Triple Quadrupole operated in positive mode on a core-shell Kinetex C18 column (50 × 2.

PBPK Absorption Modeling of Food Effect and Bioequivalence in Fed State for Two Formulations with Crystalline and Amorphous Forms of BCS 2 Class Drug in Generic Drug Development.

Prediction of the effect of food on drug's pharmacokinetics using modeling and simulation could cause difficulties due to complex in vivo processes. A generic formulation with amorphous form of BCS 2 class drug substance was developed and compared in vitro and in vivo to the reference drug product with drug substance in crystalline form. In order to approve generic formulation, some regulatory agencies are requesting to perform bioequivalence (BE) studies also in fed state.

Levels of pharmaceuticals in Slovene municipal and hospital wastewaters: a preliminary study.

Pharmaceuticals in wastewater have clearly raised concern and a broad range of analytical methods has been used to assess the risk as accurately as possible. The aim of our study was to measure and compare the concentrations of atorvastatin, bisoprolol, carbamazepine, ciprofloxacin, clofibric acid, diclofenac, fluoxetine, metoprolol, and sertraline in wastewater samples taken from one municipal and one hospital wastewater treatment plant in Slovenia and to predict the potential environmental burden using the risk quotient. In both effluents only clofibric acid and fluoxetine were not detected.

Efflux and uptake transporters involved in the disposition of bazedoxifene.

Bazedoxifene, a novel selective estrogen receptor modulator, has complex pharmacokinetics with rapid absorption, high metabolic clearance, low oral bioavailability (6.25 %) and a slow elimination phase. Our hypothesis is that drug uptake and efflux transporters may play an important role in its disposition.

A self-microemulsifying drug delivery system to overcome intestinal resveratrol toxicity and presystemic metabolism.

A mixed lipid-mixed surfactant self-microemulsifying drug delivery system (SMEDDS) was developed to exploit the health benefits of resveratrol, a Biopharmaceutical Classification System Class 2 natural polyphenol, subject to extensive intestinal presystemic metabolism. SMEDDS with a mixed lipid phase (castor oil/Capmul MCM 1:1) and a mixed surfactant phase (Kolliphor EL/Kolliphor RH 40 1:1) was developed and evaluated for its self-emulsifying properties and in vitro dispersion. The impact of SMEDDS on the permeability properties of resveratrol and its metabolite fluxes through the rat intestine and Caco-2 cells was monitored.

Decreasing acidity in a series of aldose reductase inhibitors: 2-Fluoro-4-(1H-pyrrol-1-yl)phenol as a scaffold for improved membrane permeation.

Targeting long-term diabetic complications, as well as inflammatory pathologies, aldose reductase inhibitors (ARIs) have been gaining attention over the years. In the present work, in order to address the poor membrane permeation of previously reported ARIs, derivatives of N-phenylpyrrole, bearing groups with putative pKa≥7.4, were synthesized and evaluated for aldose reductase inhibitory activity.

Mucoadhesive liposomes as new formulation for vaginal delivery of curcumin.

Local delivery to the affected area represents the optimal means by which advantageous pharmacological properties of curcumin may be fully exploited as currently, due to the biopharmaceutical limitations associated with this polyphenol, its full beneficial effects remain limited. Curcumin-containing liposomes coated with bioadhesive polymers of natural and synthetic origin (chitosan and Carbopol) were evaluated in vitro. For these purposes, an in vitro model of vaginal mucus was developed allowing the monitoring of curcumin permeability in the conditions mimicking vaginal environment.

Absorption and elimination of imatinib through the rat intestine in vitro.

Imatinib is a potent selective inhibitor of tyrosine kinases and is used primarily in the treatment of chronic myeloid leukemia and the gastrointestinal stromal tumour. Although, it is well established that imatinib is a substrate of several transport proteins which are also active in the intestinal mucosa, the mechanisms of imatinib intestinal absorption and elimination were not systematically investigated yet. To do that, we used a Sweetana-Grass type of diffusion chambers with segments of rat intestine as a model of the intestinal mucosa, measured the permeability coefficients of imatinib and its major metabolite (N-desmethyl imatinib) in both directions with and without specific and general inhibition of active transport, and calculated the efflux ratios.

The effect of lipid composition and liposome size on the release properties of liposomes-in-hydrogel.

To study the release of liposome-associated drugs into hydrogels, we designed and synthesized two pH-sensitive rhodamine derivatives to use as model compounds of different lipophilicities. The dyes were fluorescent when in the free form released from liposomes into the chitosan hydrogel, but not when incorporated within liposomes. The effect of liposomal composition, surface charge and vesicle size on the release of those incorporated dyes was evaluated.

Monitoring of imatinib targeted delivery in human leukocytes.

The success of imatinib therapy in chronic myeloid leukemia is highly influenced by its active transport into target cells. However, the methodology for analytical evaluation of intracellular drug concentration is rare and usually reliant upon the use of radioactively labeled drugs. More specifically, there is no published method available in the literature for the determination of imatinib concentration in granulocytes.

Development and evaluation of an in vitro vaginal model for assessment of drug's biopharmaceutical properties: curcumin.

Vaginal administration is a promising alternative to the per-oral route in achieving systemic or local therapeutic effects, when intestinal drug absorption is hindered by problematic biopharmaceutical drug properties. The aim of this study was to establish an in vitro vaginal model and use it to characterize biopharmaceutical properties of liposomally associated curcumin destined for vaginal delivery. The in vitro permeability, metabolism, and tissue retention of high/low permeable compounds were assessed on cow vaginal mucosa and compared to the permeabilities determined through Caco-2 cells and rat jejunum in vitro.

Simultaneous measurement of imatinib, nilotinib and dasatinib in dried blood spot by ultra high performance liquid chromatography tandem mass spectrometry.

Imatinib, dasatinib and nilotinib are three tyrosine kinase inhibitors currently used to treat Bcr-Abl1 positive chronic myelogenous leukaemia (CML). However, achieving maximum benefit with these drugs may require optimal dosing and adherence to therapy. In those cases, therapeutic drug monitoring (TDM) can be a useful tool in managing patients with CML.

Influence of hepatic and intestinal efflux transporters and their genetic variants on the pharmacokinetics and pharmacodynamics of raloxifene in osteoporosis treatment.

Raloxifene exhibits a large and unexplained interindividual variability in its pharmacokinetics and pharmacodynamics. The aim of our study was to identify transporters involved in the efflux of raloxifene and its glucuronide metabolites by various in vitro models and by an in vivo study to explore the possible involvement of P-glycoprotein (Pgp), multidrug resistance-associated protein (MRP)1, MRP2, MRP3, and breast cancer resistance protein in the observed high interindividual variability. Experiments with the parallel artificial membrane permeability assay showed the highest passive permeability for raloxifene, followed by raloxifene-6-β-glucuronide (M1), raloxifene-4'-β-glucuronide (M2), and raloxifene-6,4'-diglucuronide (M3).

Determination of permeability coefficients of ophthalmic drugs through different layers of porcine, rabbit and bovine eyes.

To treat ophthalmic diseases like glaucoma or inflammatory disorders topically applied ophthalmic formulations such as eye drops are usually used. In addition, novel ophthalmic implants releasing drug substances locally into different parts of the eye are available today. In the work presented here, the permeability coefficients of selected drugs (ciprofloxacin hydrochloride, lidocaine hydrochloride, timolol maleate) for ophthalmic tissues were determined using side-by-side diffusion chambers (so-called Ussing chambers).

Do the recommended standards for in vitro biopharmaceutic classification of drug permeability meet the "passive transport" criterion for biowaivers?

BCS based biowaivers are recognized by major regulatory agencies. An application for a biowaiver can be supported by or even based on "in vitro" measurements of drug permeability. However, guidelines limit the application of biowaivers to drug substances that are transported only by passive mechanisms.

Bio-relevant media to assess drug permeability: sodium taurocholate and lecithin combination or crude bile?

The assessment of in vivo drug absorption with in vitro permeability models demands the use of transport media with surface acting compounds. With the aim to establish their influence on in vitro permeability of 30 drugs through Caco-2 monolayers, cell vitality/integrity and micellar drug entrapment, taurocholate/lecithin (NaTC/Leci) and pig crude bile were applied. Drug permeabilities were correlated to fraction of drugs absorbed and appropriate NaTC/Leci and bile concentrations were proposed to simulate fasted/fed conditions in vitro (bile in the concentration range 1-5 v/v% or 0.

The effect of garlic supplements and phytochemicals on the ADMET properties of drugs.

Introduction: Garlic supplements have received wide public attention because of their health-beneficial effects. Although these products are considered as innocuous, several case reports and studies have shown the capacity of individual garlic phytochemicals/supplements to interfere with drug pharmacokinetics.

Areas Covered: This review covers recently published literature on garlic chemistry and composition, and provides a thorough review of published studies evaluating drug-garlic interactions.