@article{KurbanogluYarman2020,
author = {Kurbanoglu, Sevinc and Yarman, Aysu},
title = {Simultaneous determination of hydrochlorothiazide and irbesartan from pharmaceutical dosage forms with RP-HPLC},
series = {Turkish journal of pharmaceutical sciences},
volume = {17},
journal = {Turkish journal of pharmaceutical sciences},
number = {5},
publisher = {Turkish Pharmacists Association},
address = {{\c{C}}ankaya-Ankara},
issn = {1304-530X},
doi = {10.4274/tjps.galenos.2019.76094},
pages = {523 -- 527},
year = {2020},
abstract = {Objectives: In this work, a simple and rapid liquid chromatographic method for the simultaneous determination of irbesartan (IRBE) and hydrochlorothiazide (HCT) was developed and validated by reverse phase high performance liquid chromatography (RP-HPLC).
Materials and Methods: Experimental conditions such as different buffer solutions, various pH values, temperature, composition of the mobile phase, and the effect of flow rate were optimized.
Results: The developed RP-HPLC method for these antihypertensive agents was wholly validated and IRBE was detected in the linear range of 0.1-25 mu g mL(-1) and HCT was detected in the linear range of 0.25-25 mu g mL(-1). Moreover, the suggested chromatographic technique was successfully applied for the determination of the drugs in human serum and pharmaceutical dosage forms with limit of detection values of 0.008 mu g mL(-1) for IRBE and 0.012 mu g mL(-1) for HCT.
Conclusion: The proposed rapid analysis method of these antihypertensive drugs can be easily used and applied by pharmaceutical companies for which the analysis time is important.},
language = {en}
}
@article{JetzschmannYarmanRustametal.2018,
author = {Jetzschmann, Katharina J. and Yarman, Aysu and Rustam, L. and Kielb, P. and Urlacher, V. B. and Fischer, A. and Weidinger, I. M. and Wollenberger, Ulla and Scheller, Frieder W.},
title = {Molecular LEGO by domain-imprinting of cytochrome P450 BM3},
series = {Colloids and surfaces : an international journal devoted to fundamental and applied research on colloid and interfacial phenomena in relation to systems of biological origin ; B, Biointerfaces},
volume = {164},
journal = {Colloids and surfaces : an international journal devoted to fundamental and applied research on colloid and interfacial phenomena in relation to systems of biological origin ; B, Biointerfaces},
publisher = {Elsevier},
address = {Amsterdam},
issn = {0927-7765},
doi = {10.1016/j.colsurfb.2018.01.047},
pages = {240 -- 246},
year = {2018},
abstract = {Hypothesis: Electrosynthesis of the MIP nano-film after binding of the separated domains or holocytochrome BM3 via an engineered anchor should result in domain-specific cavities in the polymer layer. Experiments: Both the two domains and the holo P450 BM3 have been bound prior polymer deposition via a N-terminal engineered his6-anchor to the electrode surface. Each step of MIP preparation was characterized by cyclic voltammetry of the redox-marker ferricyanide. Rebinding after template removal was evaluated by quantifying the suppression of the diffusive permeability of the signal for ferricyanide and by the NADH-dependent reduction of cytochrome c by the reductase domain (BMR). Findings: The working hypothesis is verified by the discrimination of the two domains by the respective MIPs: The holoenzyme P450 BM3 was ca. 5.5 times more effectively recognized by the film imprinted with the oxidase domain (BMO) as compared to the BMR-MIP or the non-imprinted polymer (NIP). Obviously, a cavity is formed during the imprinting process around the hiss-tag-anchored BMR which cannot accommodate the broader BMO or the P450 BM3. The affinity of the MIP towards P450 BM3 is comparable with that to the monomer in solution. The hiss-tagged P450 BM3 binds (30 percent) stronger which shows the additive effect of the interaction with the MIP and the binding to the electrode.},
language = {en}
}
@article{JetzschmannJagerszkiDechtriratetal.2015,
author = {Jetzschmann, Katharina J. and Jagerszki, Gyula and Dechtrirat, Decha and Yarman, Aysu and Gajovic-Eichelmann, Nenad and Gilsing, Hans-Detlev and Schulz, Burkhard and Gyurcsanyi, Robert E. and Scheller, Frieder W.},
title = {Vectorially Imprinted Hybrid Nanofilm for Acetylcholinesterase Recognition},
series = {Advanced functional materials},
volume = {25},
journal = {Advanced functional materials},
number = {32},
publisher = {Wiley-VCH},
address = {Weinheim},
issn = {1616-301X},
doi = {10.1002/adfm.201501900},
pages = {5178 -- 5183},
year = {2015},
abstract = {Effective recognition of enzymatically active tetrameric acetylcholinesterase (AChE) is accomplished by a hybrid nanofilm composed of a propidium-terminated self-assembled monolayer (Prop-SAM) which binds AChE via its peripheral anionic site (PAS) and an ultrathin electrosynthesized molecularly imprinted polymer (MIP) cover layer of a novel carboxylate-modified derivative of 3,4-propylenedioxythiophene. The rebinding of the AChE to the MIP/Prop-SAM nanofilm covered electrode is detected by measuring in situ the enzymatic activity. The oxidative current of the released thiocholine is dependent on the AChE concentration from approximate to 0.04 x 10(-6) to 0.4 x 10(-6)m. An imprinting factor of 9.9 is obtained for the hybrid MIP, which is among the best values reported for protein imprinting. The dissociation constant characterizing the strength of the MIP-AChE binding is 4.2 x 10(-7)m indicating the dominant role of the PAS-Prop-SAM interaction, while the benefit of the MIP nanofilm covering the Prop-SAM layer is the effective suppression of the cross-reactivity toward competing proteins as compared with the Prop-SAM. The threefold selectivity gain provided by i) the shape-specific MIP filter, ii) the propidium-SAM, iii) signal generation only by the AChE bound to the nanofilm shows promise for assessing AChE activity levels in cerebrospinal fluid.},
language = {en}
}
@article{CasertaZhangYarmanetal.2021,
author = {Caserta, Giorgio and Zhang, Xiaorong and Yarman, Aysu and Supala, Eszter and Wollenberger, Ulla and Gyurcs{\´a}nyi, R{\´o}bert E. and Zebger, Ingo and Scheller, Frieder W.},
title = {Insights in electrosynthesis, target binding, and stability of peptide-imprinted polymer nanofilms},
series = {Electrochimica acta : the journal of the International Society of Electrochemistry (ISE)},
volume = {381},
journal = {Electrochimica acta : the journal of the International Society of Electrochemistry (ISE)},
publisher = {Elsevier},
address = {New York, NY [u.a.]},
issn = {0013-4686},
doi = {10.1016/j.electacta.2021.138236},
pages = {8},
year = {2021},
abstract = {Molecularly imprinted polymer (MIP) nanofilms have been successfully implemented for the recognition of different target molecules: however, the underlying mechanistic details remained vague. This paper provides new insights in the preparation and binding mechanism of electrosynthesized peptide-imprinted polymer nanofilms for selective recognition of the terminal pentapeptides of the beta-chains of human adult hemoglobin, HbA, and its glycated form HbA1c. To differentiate between peptides differing solely in a glucose adduct MIP nanofilms were prepared by a two-step hierarchical electrosynthesis that involves first the chemisorption of a cysteinyl derivative of the pentapeptide followed by electropolymerization of scopoletin. This approach was compared with a random single-step electrosynthesis using scopo-letin/pentapeptide mixtures. Electrochemical monitoring of the peptide binding to the MIP nanofilms by means of redox probe gating revealed a superior affinity of the hierarchical approach with a Kd value of 64.6 nM towards the related target. Changes in the electrosynthesized non-imprinted polymer and MIP nanofilms during chemical, electrochemical template removal and rebinding were substantiated in situ by monitoring the characteristic bands of both target peptides and polymer with surface enhanced infrared absorption spectroscopy. This rational approach led to MIPs with excellent selectivity and provided key mechanistic insights with respect to electrosynthesis, rebinding and stability of the formed MIPs.},
language = {en}
}
@article{BognarSupalaYarmanetal.2022,
author = {Bogn{\´a}r, Zs{\´o}fia and Supala, Eszter and Yarman, Aysu and Zhang, Xiaorong and Bier, Frank Fabian and Scheller, Frieder W. and Gyurcsanyi, R{\´o}bert E.},
title = {Peptide epitope-imprinted polymer microarrays for selective protein recognition},
series = {Chemical science / RSC, Royal Society of Chemistry},
volume = {13},
journal = {Chemical science / RSC, Royal Society of Chemistry},
number = {5},
publisher = {Royal Society of Chemistry},
address = {Cambridge},
issn = {2041-6539},
doi = {10.1039/d1sc04502d},
pages = {1263 -- 1269},
year = {2022},
abstract = {We introduce a practically generic approach for the generation of epitope-imprinted polymer-based microarrays for protein recognition on surface plasmon resonance imaging (SPRi) chips. The SPRi platform allows the subsequent rapid screening of target binding kinetics in a multiplexed and label-free manner. The versatility of such microarrays, both as synthetic and screening platform, is demonstrated through developing highly affine molecularly imprinted polymers (MIPs) for the recognition of the receptor binding domain (RBD) of SARS-CoV-2 spike protein. A characteristic nonapeptide GFNCYFPLQ from the RBD and other control peptides were microspotted onto gold SPRi chips followed by the electrosynthesis of a polyscopoletin nanofilm to generate in one step MIP arrays. A single chip screening of essential synthesis parameters, including the surface density of the template peptide and its sequence led to MIPs with dissociation constants (K-D) in the lower nanomolar range for RBD, which exceeds the affinity of RBD for its natural target, angiotensin-convertase 2 enzyme. Remarkably, the same MIPs bound SARS-CoV-2 virus like particles with even higher affinity along with excellent discrimination of influenza A (H3N2) virus. While MIPs prepared with a truncated heptapeptide template GFNCYFP showed only a slightly decreased affinity for RBD, a single mismatch in the amino acid sequence of the template, i.e. the substitution of the central cysteine with a serine, fully suppressed the RBD binding.},
language = {en}
}