Anna Jelińska

UHPLC: The Greening Face of Liquid Chromatography

Pharmaceutical analysis based on chromatographic separation is an important part of studies aimed at developing routine quality analysis of drugs. High-performance liquid chromatography (HPLC) is one of the main analytical techniques recommended for drug analysis. Although it meets many criteria vital for analysis, it is time-consuming and uses a relatively high amount of organic solvents compared to other analytical techniques. Recently, Ultra-high-performance liquid chromatography (UHPLC) has been frequently proposed as an alternative to HPLC, which means introducing an environment-friendly approach to drug analysis achieved by reducing the consumption of solvents. It also offers greater chromatographic resolution and higher sensitivity as well as requiring less time due to faster analysis. This review focuses on the basics of UHPLC, compares that technique with HPLC and discusses the possibilities of applying UHPLC for the analysis of different pharmaceuticals and biopharmaceuticals.

Analysis of Sartans: A Review

The risk of cardiovascular diseases is closely related to hypertension, high cholesterol levels, and diabetes. When these risk factors appear together they are referred to as a metabolic syndrome. In the treatment of cardiovascular diseases, a combination of antihypertensive, hypolipemiant, and antidiabetic drugs is often applied. Diuretics (chlortalidone, hydrochlorothiazide, etc.) and angiotensin II receptors antagonist (sartans) are used to control hypertension, whereas statins (fluvastatin, simvastatin, etc.) are used to reduce cholesterol levels. This review is concerned with methods for the analysis of sartans in various matrices, such as pharmaceutical formulations, environmental and biological samples, and discusses the current status of stability studies of sartans . It also presents analytical methods for the simultaneous determination of sartans, diuretics, and statins.

Evaluation of stability of cefuroxime axetil in solid state.

The effect of temperature and relative atmospheric humidity on the stability of the crystalline form of cefuroxime axetil (CFA) in solid state was investigated. CFA is a mixture of diastereomers A and B. Changes in the concentration of the two diastereomers (A and B) of CFA were recorded by means of HPLC with UV detection. The degradation of diastereomers of CFA occurring at 0% relative humidity (RH) of the ambient air is a reversible first order reaction, while that occurring in humid air (RH>50%) is an autocatalytic first order reaction relative to substrate concentration. Although it has been found, that diastereomer B is the more stable isomer, humidity has a stronger effect on this very diastereomer.

Anthracyclines still prove effective in anticancer therapy.

Present-day is developing in many fields. Many pathological processes are better understood, including carcinogenesis. Consequently, the failure of pharmacotherapy aimed at cancerous diseases is becoming explainable. At the same time, new anticancer drugs continue to be introduced. Anthracycline antibiotics are a well-known and widely used group of anticancer drugs. However, in addition to their efficiency they demonstrate severe side effects compounded by the appearance of resistant cells. Therefore, the search for new anthracycline derivatives with improved pharmacodynamic properties and fewer adverse effects is in progress, delivering promising results.

Stability-indicating derivative spectrophotometry method for the determination of biapenem in the presence of its degradation products

AbstractA first-derivative UV spectrophotometric method, with or without the subtraction technique, was developed for the determination of biapenem in pharmaceutical dosage form in the presence of its degradation products. The method was based on the measurement of first-derivative amplitudes at zero crossing point (λ = 312 nm) and the peak-to-zero technique and validated with regard to linearity, limits of detection and quantitation, selectivity and precision. The observed rate constants for the degradation of biapenem were comparable to those obtained in the stability-indicating HPLC method.

A comparison of the stability of doxorubicin and daunorubicin in solid state

The degradation of doxorubicin and daunorubcin in the solid state was studied using an HPLC method with UV detection (LiChrospher RP-18, 5 microm, 250 mm x 4 mm; mobile phase: acetonitrile-solution A 1:1, v/v (solution A: 2.88 g of laurisulfate sodium and 1.6 ml of phosphoric acid(V) in 1000 ml); flow rate - 1.4 ml min(-1); UV detection - 254 nm). The degradation of doxorubicin was a first-order reaction depending on the substrate concentration and daunorubicin degraded according to the kinetic model of autocatalysis. The dependence lnk(i)=f(1/T) was described by the equations lnk(DOX)=40.0+/-15.6-(19804+/-5682) (1/T) and lnk(DAU)=35.9+/-11.3-(16581+/-3972) (1/T) at 76.4% RH. The dependence lnk(i)=f(RH%) was described by the equations lnk(DOX)=(8.80+/-3.60) x10(-2) (RH%)-(21.50+/-2.57) and lnk(DAU)=(6.63+/-1.22)x10(-2) (RH%)-(13.35+/-1.68). The thermodynamic parameters (E(a,) DeltaH(not = a), DeltaS(not = a)) of the degradation of doxorubicin and daunorubicin were calculated. Although the degradation of doxorubicin was slower at increased temperature (353-373 K) and relative air humidity (50.9-90.0%), the differences between the influence of temperature and relative air humidity on the stability doxorubicin and of daunorubicin were not significant.

Development and validation of the stability-indicating LC-UV method for the determination of cefoselis sulphate

The stability-indicating LC assay method was developed and validated for quantitative determination of cefoselis sulphate in the presence of degradation products formed during the forced degradation studies. An isocratic, RP-HPLC method was developed with C-18 (250 × 4.6 mm, 5 µm) column and 12 mM ammonium acetate-acetonitrile (95:5 V/V) as a mobile phase. The flow rate of the mobile phase was 1.0 mL min−1. Detection wavelength was 260 nm and temperature was 30°C. Cefoselis similarly to other cephalosporins was subjected to stress conditions of degradation in aqueous solutions including hydrolysis, oxidation, photolysis and thermal degradation. The developed method was validated with regard to linearity, accuracy, precision, selectivity and robustness. The method was applied successfully for identification and determination of cefoselis sulphate in pharmaceuticals and during kinetic studies.

Kinetics of cefamandole nafate degradation in solid phase

The influence of temperature and relative humidity (RH) on the stability of cefamandole (CM) nafate sodium in the solid phase was investigated. Changes in the concentration of cefemandole nafate sodium were recorded using HPLC with UV detection. The method was validated for the following parameters: selectivity, linearity, precision, limit of detection and sensitivity. It showed good linearity (r=0.9996) in the range 0.4 x 10(-4)-5.6 x 10(-4) g ml(-1) using a LiChrospher RP-18 column and as mobile phase acetonitryle-triethylamine (10% v/v, adjusted to pH 2.5 with phosphoric acid (84%) and diluted with water) (35:65). The degradation of CM occurring at 0% RH of the ambient air and at air humidity RH>50% is a first-order reaction relative to substrate concentration. The first-order rate constants (k) were determined for CM degradation in dry air at 373, 383, 388 and 393 K, at air humidity RH=76.4% at 323, 333, 343 and 353 K, and at 353 K at air humidity RH>50%. The kinetic and thermodynamic parameters of the decomposition were calculated.

Determining whether curcumin degradation/condensation is actually bioactivation (Review)

Curcumin has been shown to exert therapeutic or protective effects against a variety of diseases, such as cancer, pulmonary diseases, neurological, liver, metabolic, autoimmune, cardiovascular diseases and numerous other chronic ailments. Over 116 clinical studies on curcumin in humans were registered with the US National Institutes of Health in 2015. However, it is mystifying how curcumin can be so effective in the treatment of many diseases since it has very low water solubility and bioavailability. Furthermore, curcumin is not stable under various conditions; its degradation or condensation into different bioactive compounds may be responsible for its biological activities rather than curcumin itself. In this review, we provide evidence of curcumin degradation and condensation into different compounds which have or may have health benefits themselves. Literature reviews strongly suggest that these molecules contribute to the observed health benefits, rather than curcumin itself.

Stability of epidoxorubicin in solid state.

The influence of temperature and relative air humidity on the stability of epidoxorubicin hydrochloride (EP) was investigated. The degradation of the substance studied was determined: (a) in dry air at 393K, (b) at relative air humidity ~76% at 333K, 343K, 353K, 363K and 373K, (c) in the relative air humidity range 50-90% at 363K. The degradation of EP in the atmosphere of increased relative air humidity was a first-order reaction relative to substance concentration and in dry, hot air (RH 0%; 393K) is a reversible first-order reaction relative to substance concentration. The dependences lnk=f(1/T) and lnk=f(RH%) were described by the equation: lnk=(35.1±10.9)-(16,250±3823)(1/T) and lnk=(3.79±3.34) × 10(-2) (RH%)-(12.9±2.4), respectively. The kinetic and thermodynamic parameters of EP degradation were calculated. The parameters of separation were following: LiChrospher RP-18 column, 5 μm, 250 mm × 4 mm; mobile phase: the mixture of equal volume of acetonitrile and the solution containing 2.88 gl(-1) of sodium laurisulfate and 2.25 ml l(-1) of phosphoric acid (V) 85%; flow rate: 1.0 ml min (-1); UV detection - 254 nm.