Pregled analitičkih metoda za određivanje vankomicina i teikoplanina u biološkom materijalu

Background. Teicoplanin and vancomycin are glycopeptide antibiotics currently in use for treatment of multidrug-resistant bacterial infections. Scope and Approach. Severe undesirable effects, such as ototoxicity, nephrotoxicity and neutropenia have been reported for vancomycin and teicoplanin, which necessitates monitoring the concentration of these two drugs in different biological samples. In order to obtain precise and accurate results, sensitive, reliable and fast methods are necessary. The main aim of this mini review is to give a clear and concise overview of the recently developed, validated, novel and improved methods for glycopeptide antibiotic analyses in various biological matrices. Also, the variability of the matrices requires optimal and effective sample preparation procedures to be developed, and so these are discussed. Key Findings and Conclusions. Different liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods have been described for quantitative determination of glycopeptide antibiotics in various biological matrices. It was shown that protein precipitation was a convenient method for sample preparation despite the high number of novel sample preparation methods.Uvod. Teikoplanin i vankomicin su antibiotici glikopeptidne strukture koji se trenutno koriste u terapiji multirezistentnih bakterijskih infekcija. Cilj i pristup. Ozbiljni neželjeni efekti vankomicina i teikoplanina kao što su ototoksičnost, nefrotoksičnost i neutropenija zahtevaju njihovo praćenje u različitim tipovima biološkog materijala. Osetljiva, pouzdana i brza metoda potrebna je u cilju dobijanja tačnih i preciznih podataka o koncentraciji pomenutih jedinjenja. Cilj ovog pregleda je da da jasan i kratak prikaz o razvijenim i validiranim novim, ili unapređenim metodama za analizu glikopeptidnih antibiotika u različitim biološkim matriksima. Takođe, u radu su opisane i metode pripreme uzorka upravo zbog raznovrsnosti biološkog materijala. Ključni nalazi i zaključak. Opisane su raznovrsne LC-MS/MS metode za određivanje glikopeptidnih antibiotika u biološkom materijalu. Primećeno je da je precipitacija proteina pogodna metoda pripreme uzorka bez obzira na broj novijih metoda pripreme koje se koriste

Određivanje sadržaja pseudoefedrina, paracetamola i askorbinske kiseline u peroralnom prašku primenom reverzno-fazne tečne hromatografije

For the simultaneous analysis of multicomponent mixture containing pseudoephedrine, paracetamole and ascorbic acid two RP-HPLC methods were developed. Separation were performed on Hewlett Packard 1100 system which consisted of HP 1100 binary pump, HP 1100 UV/VIS detector and HP ChemStation for the automatic data evaluation. Methods were developed, e. g. chromatographic conditiond settled, methods submited to method validation and then applied for the determination of content of multicomponent powder.The best separation was achived on Platinium Alltech Amino 150 x 4.6 mm, 5 mm particle size column, at 30°C. Injection volume was 20mL. Mobile phase in mehtod I was a mixture of methanol-water (30:70 V/V), pH 2.5, and in mehtod II was a mixture methanol-water (60:40 V/V), pH 2.9. pH of the mobile phases were adjusted with 85% ortophosphoric acid. Detection was performed at 214 nm in mehtod I and at 257 nm in method II. Flow rate was 1 mLmin-1. Developed methods were validated. Obtained results showed that both methods are suitable for routine analysis of pharmaceutical dosage forms which contain pseudoephedrine, paracetamole and ascorbic acid.Za istovremenu analizu trokomponentne smeše koja sadrži pseudoefedrin, paracetamol i askorbinsku kiselinu postavljene su dve metode reverzno-fazne tečne hromatografije pod visokim pritiskom (RP-HPLC). Hromatografski sistem Hewlett Packard 1100 koji čini HP 1100 binarna pumpa, HP 1100 UV-VIS detektor i HP ChemStation za automatsku obradu podataka korišćen je za hromatografsko razdvajanje. Postupak je obuhvatio definisanje hromatografskih uslova, validaciju postavljenih metoda, kao i njihovu primenu za ispitivanje sadržaja pseudoefedrina, paracetamola i askorbinske kiseline u peroralnom prašku. Optimalna separacija postignuta je u koloni Platinium Alltech Amino 150 mm x 4,6 mm, 5 mm veličine čestica, na temperaturi kolone od 30°C. Volumen injektovanja bio je 20 mL. Mobilna faza u metodi I bila je smeša metanol-voda (30:70 V/V), pH vrednost podešena na 2,5, a u metodi II smeša metanol-voda (60:40 V/V), pH vrednost podešena na 2,9. pH mobilne faze je podešavan sa 85%-tnom orto-fosfornom kiselinom. Talasna dužina detekcije bila je 214 nm u metodi I i 257 nm u metodi II. Protok mobilne faze za obe metode bio je 1 mL min-1. Postavljene metode su validirane i na osnovu dobijenih parametara procenjeno je da obe predložene metode mogu da se primene za analizu peroralnog praška koji sadrži paracetamol, pseudoefedrin i askorbinsku kiselinu

Aspekti primene DryLab® softvera u optimizaciji i proceni robusnosti hromatografskih metoda

In this review article, aspects of DryLab® software application in liquid chromatography are given. Literature survey shows wide application of software for chromatography method development, optimization, as well as for robustness testing. Earlier versions of DryLab®software enabled the simultaneous monitoring of the impact of two parameters on the selected system response, as an upgraded version of the software provides significantly more opportunities. Namely, the new DryLab®software version enables fulfilling requirements given by Quality by Design (QbD) concept through a systematic approach to the development of chromatographic methods, and the construction of a 3D cube which provides the visualization of a Design Space. In addition, when running liquid chromatography methods on a routine basis software can be a useful tool for optimization process in order to minimize retention times and run time, as well as facilitating the transfer of a method (DryLab® data can be sent electronically). Finally, DryLab®software provides useful information about the method and can be applied to training of young analysts without performing experiments, while saving time, money, and laboratory instruments.U preglednom radu prikazani su aspekti primene DryLab® softvera u tečnoj hromatografiji. Literaturni pregled pokazuje široku primenu softvera u fazi postavljanja nove hromatografske metode, optimizaciji, kao i u proceni robusnosti metode. Ranije verzije DryLab® softvera omogućavale su istovremeno praćenje uticaja dva faktora na odabrani odgovor sistema, dok unapređene verzije softvera daju značajno veće mogućnosti. Novije verzije DryLab® softvera omogućavaju ispunjavanje zahteva određenih Quality by Design (QbD) konceptom kroz sistematičan prilaz razvoju hromatografske metode, kao i kroz konstruisanje 3D kocke kojom se omogućava vizuelni prikaz Design space-a. Pored toga, u rutinskoj primeni metoda tečne hromatografije softver može biti koristan 'alat' za optimizaciju u cilju skraćenja retencionih vremena i trajanja analize, kao i olakšavanja transfera metoda (podaci dobijeni uz pomoć DryLab®-a se mogu slati elektronskim putem). Na kraju, upotrebom DryLab® softvera dobijaju se korisne informacije o metodi, a uz to može služiti za obučavanje mladih analitičara bez izvođenja eksperimenata, uz istovremenu uštedu vremena, novca i laboratorijske opreme

Studije forsirane degradacije amlodipin-besilata i bisoprolol-fumarata primjenom tečne hromatografije hidrofilnih interakcija

Currently, in pharmaceutical analysis, great importance is given to forced degradation studies, which can greatly help to predict the shelf life of the drug, but also for identification of possible degradation products. These studies enable investigation of stability indicating method, then it is used to test the active substances intrinsic/inner molecular stability, as well as defining active substances impurity profiles. In this work forced degradation studies of amlodipine besylate and bisoprolol fumarate either individually and in mixtures, was performed, where the method of hydrophilic interaction liquid chromatography was used, and any possible changes in the concentration of samples were followed. The results showed that the test compounds are sensitive to the tested stress agents, especially amlodipine besylate, and that both of these compounds showed increased stability in the mixture in comparison to individual analysis.U savremenim farmaceutskim analizama danas se veliki značaj pridaje studijama forsirane degradacije, koje mogu u velikoj mjeri pomoći u predviđanju roka upotrebe lijeka, ali i u identifikaciji mogućih proizvoda degradacije. Ove studije omogućavaju ispitivanje specifičnosti stability indicating metode, zatim koriste se za ispitivanje intrinzičke/unutrašnje stabilnosti molekule aktivnih supstanci, kao i za definisanje profila nečistoća aktivnih supstanci. U ovom radu vršena je studija forsirane degradacije amlodipin-besilata i bisoprolol-fumarata pojedinačno i u smješi, gdje se kao metoda koristila tečna hromatografija hidrofilnih interakcija, kojom su se pratile promjene koncentracije ispitivanih uzoraka. Rezultati ispitivanja pokazali su da su ispitivana jedinjenja osjetljiva na većinu ispitivanih stres agenasa, naročito amlodipinbesilat, kao i da su oba ova jedinjenja pokazala veću stabilnost u smješi, nego kad su pojedinačno analizirana

Quality by Design approach in the development of hydrophilic interaction liquid chromatographic method for the analysis of iohexol and its impurities

This study presents the development of hydrophilic interaction liquid chromatographic method for the analysis of iohexol, its endo-isomer and three impurities following Quality by Design (QbD) approach. The main objective of the method was to identify the conditions where adequate separation quality in minimal analysis duration could be achieved within a robust region that guarantees the stability of method performance. The relationship between critical process parameters (acetonitrile content in the mobile phase, pH of the water phase and ammonium acetate concentration in the water phase) and critical quality attributes is created applying design of experiments methodology. The defined mathematical models and Monte Carlo simulation are used to evaluate the risk of uncertainty in models prediction and incertitude in adjusting the process parameters and to identify the design space. The borders of the design space are experimentally verified and confirmed that the quality of the method is preserved in this region. Moreover, Plackett-Burman design is applied for experimental robustness testing and method is fully validated to verify the adequacy of selected optimal conditions: the analytical column ZIC HILIC (100 mm x 4.6 mm, 5 mu m particle size); mobile phase consisted of acetonitrile-water phase (72 mM ammonium acetate, pH adjusted to 6.5 with glacial acetic acid) (86.7:13.3) v/v; column temperature 25 degrees C, mobile phase flow rate 1 mL min(-1), wavelength of detection 254 nm.This is peer-reviewed version of the following article: Jovanović, M.; Rakić, T.; Tumpa, A.; Jančić Stojanović, B. Quality by Design Approach in the Development of Hydrophilic Interaction Liquid Chromatographic Method for the Analysis of Iohexol and Its Impurities. J. Pharm. Biomed. Anal. 2015, 110, 42–48. [https://doi.org/10.1016/j.jpba.2015.02.046

Investigation of olopatadine hydrochloride under stress conditions by hydrophilic interaction liquid chromatography [Ispitivanje olopatadin-hidrohlorida pod stres uslovima metodom tečne hromatografije hidrofilnih interakcija]

The purpose of the present research was to conduct stress degradation studies on the olopatadine hydrochloride, an antiallergic drug, using the hydrophilic interaction liquid chromatography (HILIC). HILIC requires the utilization of polar and moderately polar stationary phases and aqueous-organic mobile phase usually containing more than 70% of organic solvent. In this study, olopatadine hydrochloride was subjected to acid and base hydrolysis, oxidation and thermolytic degradation in order to estimate its stability under different stress conditions recommended by ICHQ1A (R2) guideline. Degree of degradation was followed by HILIC method. The chromatographic conditions were: column Betasil Cyano (100 mmx4.6 mm, 5 mu m particle size), mobile phase consisted of acetonitrile and ammonium acetate 5 mM (pH adjusted to 4.50) in ratio 85: 15 V/V, flow rate was 1 mL min(-1), column temperature was set at 30 degrees C and detection was performed at 257 nm. Results obtained for stress studies indicated that olopatadine hydrochloride underwent transformation under acidic and oxidative (30% hydrogen peroxyde) conditions showing high degree of degradation. Furthermore, it was found that olopatadine hydrochloride is relatively stable when exposed to thermal (60 degrees C) and basic (1 M NaOH) conditions. Therewith, kinetics of degradation reaction was determined with an aim to define the corresponding reaction rate constants and half-lives. Firstly, the order of the reaction was evaluated experimentally using the integral method. Based on the calculated values of the correlation coefficients, it was shown that the acidic, basic and oxidative degradation are the second-order reaction. High stability under basic conditions was achieved on the basis of the great degradation half-life values. Also, it has been verified that acidic degradation is the fastest reaction

Central Composite Design with/without Artificial Neural Networks in Microemulsion Liquid Chromatography Separation Robustness Testing

In past few years, for overcoming some analytical problems in liquid chromatography, the microemulsion as eluent was employed. Due to the strict regulatory requirements, robustness testing became important especially when proposing completely new method such as microemulsion liquid chromatography (MELC). In this paper robustness testing of MELC method, proposed for carbamazepine and its impurities (iminostilben and iminodibenzyl) separation, was done using two different approaches both based on experiments defined using central composite design (CCD). Input and output data from CCD were either handled as second order polynomials and tested with Analysis of variance (ANOVA), or as variables in Artificial Neural Networks (ANN). From both approaches appropriate conclusions about system robustness were distinguished, e. g. that the influence of surfactant content on chromatographic retention was the largest for all analytes, meaning that small changes in its concentration will strongly influenced on chromatographic retention. On the other hand influence of the pH of the mobile phase proved to be negligible, meaning that the substances are mainly distributed in the interfacial layer. ANN gave better results and proved to be better tool for explanation and understanding of investigated factors effects on the chromatographic system and for definition of the robustness limits

Plaket-Burman dizajn u proceni robusnosti metode tečne hromatografije za određivanje sadržaja natrijum-valproata

In this paper, application of Plackett-Burman design in robustness testing of liquid chromatographic method for determination of sodium valproate. As factors which could have influence on method's robustness content of acetonitrile, concentration of sodium dihydrogenphosphate, pH of the mobile phase, column's temperature, flow rate and wavelenght were investigated. In aim to create plan of experiments for Plackett-Burman design on six real factors, 5 dummies were added. In total, 11 factors were investigated throught 12 experiments. As qualitative responses retention times, number of theoretical plates and peak symmetry were followed while as quantitative response peak area was followed. On the basis of the obtained results with statistical and graphical methods, influence of investigated factors on system responses were defined. Further, for significant factors non-significant interval was defined e. g. range in which factor could be change without influence on response. Finally, results were used for determination of parameters for system suitability tests.U ovom radu opisana je primena Plaket-Burman dizajna u proceni robusnosti metode tečne hromatografije za određivanje sadržaja natrijum-valproata. Kao faktori koji mogu uticati na robusnost metode ispitani su sadržaj acetonitrila, koncentracija natrijum-dihidrogenfosfata, pH vrednost mobilne faze, temperatura kolone, protok mobilne faze i talasna dužina detekcije. U cilju kreiranja plana eksperimenta prema Plaket-Burman dizajnu, na 6 pravih faktora dodato je 5 veštačkih faktora i tako je ispitano 11 faktora izvođenjem 12 eksperimenata. Kao odgovori sistema praćeni su retenciono vreme, broj teorijskih platoa i simetrija pika kao kvalitativni odgovori, dok je kao kvantitativni odgovor praćena površina pika. Na osnovu dobijenih rezultata, a primenom odgovarajućih statističkih i grafičkih metoda, procenjen je uticaj ispitivanih faktora na posmatrane odgovore sistema. Pored toga, za značajne faktore određen je interval pouzdanosti tj. opseg u okviru koga se mogu menjati, a da to ne utiče značajno na odgovor sistema. Na kraju, na osnovu dobijenih rezultata, određeni su i parametri za proveru pogodnosti sistema

Optimizacija HILIC metode za analizu bisoprolola i njegovih nečistoća uz procenu mogućnosti variranja položaja pikova

This paper presents the robust optimization of hydrophilic interaction liquid chromatographic method for the analysis of bisoprolol and its impurities A and C. Chemometric strategy is applied for detailed understanding of system's behavior and establishing the mathematical relationship between investigated factors (acetonitrile content in the mobile phase, pH of the water phase and buffer concentration in the water phase) and chromatographic responses. Grid point search methodology is then performed with the aim to identify the point with satisfactory separation quality for all analyzed substances and to achieve minimal analysis duration. Oversized chromatograms are made creating an extra band broadening for each chromatographic peak corresponding to the value of standard deviation in order to evaluate the incertitude originating from the model uncertainty. On the other hand, the uncertainty originating from the variation of experimental parameters is assessed by simulated experimental design robustness testing. Finally, the obtained robust optimal conditions were: chromatographic column Kinetex HILIC 100Å (100 mm x 4.5 mm, 2.6 mm particle size); mobile phase composed of acetonitrile - water phase (35 mM ammonium acetate, pH 4.9 adjusted with glacial acetic acid) (85:15 v/v); flow rate 1 mL min-1, column temperature 30°C and UV detection at 254 nm.U ovom radu prikazana je optimizacija metode tečne hromatografije hidrofilnih interakcija za analizu bisoprolola i njegovih nečistoća A i C uz procenu mogućnosti variranja položaja pikova. Primenjena je hemometrijska strategija za detaljno razumevanje ponašanja sistema i uspostavljanje matematičke veze između ispitivanih faktora (sadržaj acetonitrila u mobilnoj fazi, pH vrednost vodene faze i koncentracija pufera u vodenoj fazi) i hromatografskih odgovora. Enumerativna tehnika optimizacije upotrebljena je za identifikaciju tačke koja pokazuje zadovoljavajući kvalitet razdvajanja svih ispitivanih supstanci i minimalno vreme trajanja analize. Kreirani su prošireni hromatogrami širenjem pikova svih ispitivanih supstanci za vrednosti standardne devijacije kako bi se procenila mogućnost greške odgovora koja potiče iz greške matematičkog modela. Mogućnost greške koja potiče iz greške u podešavanju eksperimentalnih parametara procenjena je simuliranim testiranjem robusnosti primenom eksperimentalnog dizajna. Konačno, dobijeni optimalni uslovi bili su: hromatografska kolona Kinetex HILIC 100Å (100 mm x 4,5 mm, 2,6 mm veličina čestica); mobilna faza sastavljena od smeše acetonitril - vodena faza (35 mM amonijum-acetat, pH 4,9 podešen glacijalnom sirćetnom kiselinom) (85:15 v/v); protok 1 mL min-1, temperatura kolone 30°C i UV detekcija na 254 nm

Multikriterijumski pristup optimizaciji metode micelarne tečne hromatografije za analizu atorvastatina i njegovih nečistoća

In the current paper, multi-criteria decision making (MCDM) approach was applied to optimize micellar liquid chromatography (MLC) intended for the pharmaceutical analysis of atorvastatin and its impurities, trans-atorvastatin and desfluoro-atorvastatin. MLC is a reversedphase liquid chromatographic (RPLC) mode where the modification of mobile phase leads to the stationary phase modification. This results in the diverse interactions (hydrophobic, ionic and steric) significantly affecting retention and selectivity. For that reason double chained surfactant sodium dioctyl sulfosuccinate - AOT (Aerosol OT), with oxygen atoms in its tails, was used for the first time in such kind of separation. As the most efficient way to investigate a high number of factors, and simultaneously optimize defined antagonistic objectives (minimization of run time and maximization of atorvastatin and trans-atorvastatin resolution) MCDM approach was employed. Central composite design (CCD) with fractional factorial design, ± 0.5 star design and four replications in central point was used to define plan of experiments. Five responses selected during method development were optimized simultaneously using Derringer's desirability function. The predicted optimum was: 32 % acetonitrile, 2 % ethylene glycol, 66 % 6.4 mmol L-1 AOT in 20 mmol L-1 ammonium acetate, pH of the water phase 5.50 adjusted with acetic acid, flow rate 1.15 mL min-1 and column temperature of 10C.U ovom radu, za optimizaciju metode micelarne tečne hromatografije (MLC) namenjene za farmaceutsku analizu atorvastatina i njegovih nečistoća, trans-atorvastatina i desfluoroatorvastatina primenjen je multikriterijumski pristup. MLC je oblik reverzno-fazne tečne hromatografije gde promene u mobilnoj fazi dovode i do modifikacije stacionarne faze. Ovo rezultuje različitim interakcijama (hidrofobnim, jonskim, sternim) sa značajnim uticajem na retenciju i selektivnost. Zbog toga je za separaciju odabran surfaktant koji sadrži dvostruki lanac i atom kiseonika, natrijum dioktil sulfosukcinat - AOT (Aerosol OT). Kao najefikasniji način za istraživanje velikog broja faktora i istovremenu optimizaciju suprotstavljenih ciljeva (minimizacija vremena trajanja razdvajanja i maksimizacija rezolucije između atorvastatina i trans-atorvastatina) primenjena je multikriterijumska optimizacija. Centralni kompozicioni dizajn (CCD) sa frakcionim faktorskim dizajnom, ± 0.5 zvezda dizajnom i četiri replikacije u centralnoj tački korišćen je za definisanje plana eksperimenta. Korišćenjem Derringer funkcije poželjnih odgovora, optimizirano je pet odgovora. Predviđeni optimalni uslovi bili su: 32 % acetonitrila, 2 % etilen-glikola, 66 % 6,4 mmol L-1 AOT u 20 mmol L-1 amonijum-acetatu, pH vodene faze 5,50 podešen sirćetnom kiselinom, protok 1,15 mL min-1 uz temperaturu kolone 10 C