Metal-bağlayan amino asitlerce zengin peptidler ile fonksiyonlanmış nanoparçacıkların hazırlanması ve teranostik uygulamaları

Protein modifikasyonu ve değişikliği, diyabet, alzheimer ve kanser gibi çok faktörlü ve yaşa bağlı birçok hastalıkta önemli rol oynamaktadır. İleri glikasyon son ürünlerinin (AGE) ve ileri oksidasyon protein ürünlerinin (AOPP) oluşumu gibi değişiklikler protein agregasyon ve amiloid fibril oluşumuna katkıda bulunmaları nedeni ile organizmaya zarar verebilirler. Bu nedenle bu protein modifikasyonlarını önleyebilecek ve verimli bir şekilde düzeltebilecek tedavi seçeneklerinin bulunması büyük önem taşımaktadır. Bununla birlikte, bir tedavinin hedefine ulaşması için, vücutta, dokularda ve hücrelerde bulunan çeşitli kimyasal ve fiziksel mekanizmalar ve bariyerlerle karşı karşıya kalması söz konusudur. Örneğin, kan-beyin bariyeri gibi. Bu nedenle, istenmeyen etkileşimler ve degradasyonun aşılması için yeni nano mühendislik formülasyonları üzerine çalışmalar yoğunlaşmıştır. Bu bağlamda, bu çalışmada olası bariyerlerin aşılması, protein modifikasyonlarının önlenmesi ve hedefe yönelik tedavilerin geliştirilmesi amacı ile nano-taşıyıcılar ve spesifik peptidler kullanarak teranostik bir yaklaşımın geliştirilmesi hedeflendi. Bu amaçla farklı çalışmalar yapılmış olup ilk olarak, karnosin gibi bazı peptitlerin, iki değerlikli bir metal olan çinko varlığında hazırlanan niozomların etkinliği araştırıldı. Sonrasında ise, her yapının içeriğin performansı üzerindeki avantajlarını görmek için niozomlar ve polimerzomlar dâhil olmak üzere farklı enkapsülasyon türleri üzerinde karşılaştırmalı bir çalışma yapıldı. Elde edilen sonuçlar doğrultusunda, kematerapötik bir kanser ilacı olan doksorubisini kapsayan bir teranostik (terapötik ve tanı) polimerzom tasarımı gerçekleştirildi. Bu bağlamda polimerzom yüzeyine nanotaşıyıcının penetrasyon kapasitesini arttırmak için Histatin 5 peptidi bağlanarak uygulanan ilaç miktarının düşürülmesi sağlandı. Elde edilen veriler, ilaca direnç mekanizmalarının potansiyel olarak tersine çevrilmesiyle ilacın kanser hücreleri üzerinde etkisinin önemli bir şekilde arttığını gösterdi. Diğer yandan hazırlanan polimerzomların floresansının izlenmesi ile gerek nano-taşıyıcı tabanlı tedavinin etkinliğinin ve seyrinin takip edilmesi gerekse tedavinin ayarlanmasına da olanak sağlayabileceği gözlemlendi. Sonuç olarak bu tez kapsamında çok ilginç olumlu sonuçlar gösteren orijinal bir teranostik yapı tanımlandı. Ancak ileride yapılacak hem in vitro hem de in vivo sinyal yolları da dâhil olmak üzere mekanistik çalışmaların yapılması gerekliliği açıktır.Protein modification and alteration are important factors in many age-related diseases such as diabetes, Alzheimer's disease, and cancer. Modifications like the formation of advanced glycation end-products (AGE) and advanced oxidation protein products (AOPP) can cause harm to the organism and may contribute to protein aggregation and amyloid fibrils formation. Other protein can also aggregate under certain conditions such as cancer. Consequently, finding treatment options that can efficiently correct and prevent these protein modifications is of substantial importance. However, for a treatment to reach its target, it faces various chemical and physical mechanisms and barriers present in the body, tissues, and cells. For example, some organs like the brain are difficult to reach due to the blood-brain barrier. As such, new Nano ngineered formulations were sought to bypass unwanted interactions and degradation. Thus, the current thesis aimed for the development of a theranostic approach using nanocarriers and specific peptides to overcome the barriers and act on the prevention and treatment of protein modifications. This work first explored the efficiency of some peptides such as carnosine in the presence of a divalent metal zinc and when encapsulated inside niozomes. The aim was to understand if the combination could enhance the activity of the peptide for the upcoming steps. After that, a comparative study on different types of encapsulations was performed including niozomes and polymersomes to see the advantages of each structure on the performance of the content. The last steps made use of the previous results to design a theranostic polymersome encapsulating the anti-cancer drug doxorubicin (acts both as a therapeutic agent and has fluorescence for diagnostic). The polymersome surface was decorated using a cell-penetrating peptide called Histatin 5 to enhance the penetration capacity of the nanocarrier while lowering the drug amount administered. The obtained data showed an important enhancement of the drug over cancer cells with a potential reversal of drug-resistance mechanisms. The fluorescence observation allows the continuous tracking of the administered nanocarrier-based treatment which has a great potential in clinical applications by following the treatment course, effect, and adjusting the therapy directly. While the current thesis has described an original theranostic structure that has yet to be seen in the literature and showing very interesting positive results, it is necessary to further analyze the mechanistic effects including signaling pathways both in vitro and especially in vivo

Noninvasive Optical Sensor for the Detection of Cocaine and Methamphetamine in Saliva Using Rhodamine B-Labeled Polymersomes

Drug abuse is an alarming subject affecting modern society. Unlike alcohol consumption control, substance abuse monitoring still lacks standardized, non-invasive, and efficient biosensors for on-site diagnostics. Most of the approaches are based on blood sampling and traditional chromatographical techniques. Here, we propose two colorimetric lateral flow immunoassays (LFIA) using Rhodamine B-loaded polymersomes for cocaine (COC) and methamphetamine (METH) detection on saliva samples. Polymersomes were synthesized from methoxy polyethylene glycol and polycaprolactone and then loaded with the dye. Furthermore, the bioconjugation of the specific antibodies on the surface was confirmed via various analytical methods. The LFIA platform was based on a competitive type that is more suitable for detecting small-sized molecules. The sensitivity of the LFIA was quantitatively measured using smartphone-assisted imaging analysis and showed a limit of detection (LOD) of 0.49 ng/mL (COC) and 0.37 ng/mL (METH). Moreover, the specificity was also investigated against various interferents. The analytical performance of the LFIA platform was tested over synthetic and real human saliva, which showed an overall accuracy of 97% and 98.4%, respectively. The LFIA offers excellent stability under various salivary conditions (pH and incubation time) and keeps steady performance when comparing spiked buffer with synthetic and human saliva. The use of non-invasive sampling such as saliva in combination with on-site sensing devices can be of great potential for future applications and implementation of portable biosensors.Republic of Turkey, Ministry of Development [2016K121190]This work was supported by the Republic of Turkey, Ministry of Development through the Infrastructure of EGE MATAL, Ege University, Izmir, under Grant 2016K121190

Ionic liquid-hydrogel hybrid material for enhanced electron transfer and sensitivity towards electrochemical detection of methamphetamine

Reliable onsite biosensors for detecting drugs of abuse are of critical importance for the current society. Electrochemical sensors, especially screen-printed electrode (SPE)-based sensors, are a strong candidate for onsite drug detection. Although many SPE-based sensors are being developed, enhancing these tools' sensitivity and analytical capacity is a continuous endeavor. Here, we propose a novel approach for SPE surface modification using a combination of hydrogel, ionic liquid, and specific antibodies to detect methamphetamine in human saliva samples. The hydrogel-ionic liquid (ionogel) was synthesized from gelatin, PEG, and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. FTIR and SEM were used to characterize the material before it was applied over a screen-printed gold electrode for electrochemical measurements using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). After optimization, the calibration of the proposed sensor showed a detection range between 5.0 and 1000 ng/mL with a LOD = 0.56 ng/mL in PBS. Application of the sensor with spiked human saliva demonstrated enhanced sensitivity with a LOD = 0.72 ng/mL. The repeatability and reproducibility of the proposed biosensor demonstrated a coefficient of variance (CV%) reaching 6.92% and 2.53%, respectively. The biosensor showed a high specificity toward methamphetamine compared to other interferents. The current ionogel-based electrochemical immunosensor offers a promising and versatile tool for sensitive onsite detection of substance abuse. (C) 2022 Elsevier B.V. All rights reserved.The Republic of Turkey-Ministry of Development supported the infrastructure of EGE MATAL (Ege University/Izmir) via the 2016K121190 grant.Republic of Turkey-Ministry of Development [2016K121190

Novel technologies in detection, treatment and prevention of substance use disorders

Substance use disorders are a widely recognized problem, which affects various levels of communities and influenced the world socioeconomically. Its source is deeply embedded in the global population. In order to fight against such an adversary, governments have spared no efforts in implementing substance abuse treatment centers and funding research to develop treatments and prevention procedures. In this review, we will discuss the use of immunological-based treatments and detection kit technologies. We will be detailing the steps followed to produce performant antibodies (antigens, carriers, and adjuvants) focusing on cocaine and methamphetamine as examples. Furthermore, part of this review is dedicated to substance use detection. Owing to novel technologies such as bio-functional polymeric surfaces and biosensors manufacturing, detection has become a more convenient method with the fast and on-site developed devices. Commercially available devices are able to test substance use disorders in urine, saliva, hair, and sweat. This improvement has had a tremendous impact on the prevention of driving under influence and other illicit behaviors. Lastly, substance abuse became a major issue involving the cooperation of experts on all levels to devise better treatment programs and prevent abuse-based accidents, injury and death. Keywords: Substance use disorder, Cocaine/methamphetamine, Drug detection, Biosensors, Immunotherap

Self-assembled block copolymers in ionic liquids: Recent advances and practical applications

WOS:000610844800116Ionic liquids (ILs) are seen as liquids with great and novel potential in various applications such as separation materials, reaction medium, and energy devices. They have garnered great interest in their potential as a liquid-based molecular self-assembly medium that can produce innovative materials with distinctive criteria that have never been observed in traditional soft materials such as water and solvents. Here, recent advances and practical application of block copolymer (BCP) self-assembly in ILs are discussed focusing on the formation of the microstructure depending on dilute or concentrated BCPs. on the other hand, ion gels prepared from self-assembled BCPs attracted significant interest due to the outstanding tenability features (physical, viscoelasticity, and solution processability) without hindering ILs properties (nonvolatility, nonflammability, and high ionic conductivity). Lastly, the applicability of such technology is already in progress with a great interest seen in electrochemistry, batteries, actuators, electrolyte-gated transistors, and nano-delivery vehicles. (C) 2020 Elsevier B.V. All rights reserved

Nanohybrid carriers: the yin-yang equilibrium between natural and synthetic in biomedicine

ZIHNIOGLU, FIGEN/0000-0001-8216-7004WOS: 000542957800001PubMed: 32484498Nanotechnology has seen an outburst in biomedicine applications through the use of nanoparticles of different sources in therapy and diagnostics. the needs of theranostics evolved through the years for the development of tailored treatments. in this regard, nanocarriers have shown a great impact on the fieldviathe use of natural lipidic vesicles for drug delivery. This breakthrough allowed the medical field to protect the drug from undesired interactions in the bloodstream and lowered the drug load usually given to reach therapeutical doses. Nanocarriers further continued by using block polymers to create more stable structures with higher protection levels of their content. in this review, we introduce both lipidic and polymeric vesicles with their specific characteristics and discuss the advantages and disadvantages of each type which was taken as a base to introduce the newly known lipid-polymer hybrids that take the advantages from both sides to present an interesting approach to regulate the physicochemical features, pharmacokinetics and other parameters used in tailoring treatments for cancer therapy. in addition, from the many hybrids proposed we have focused our efforts in discussing two major groups that are lipid-polymer hybrid nanoparticles LPHNs (polymersomes inside liposomes), and capsosomes (liposomes inside polymersomes) showing the many potential benefits of combining lipids and polymers for biomedicine

Zinc enhances carnosine inhibitory effect against structural and functional age-related protein alterations in an albumin glycoxidation model

ZIHNIOGLU, FIGEN/0000-0001-8216-7004WOS: 000574119900001PubMed: 32997290Age-related complications including protein alterations seen in diabetes and Alzheimer's disease are a major issue due to their accumulation and deleterious effects. This report aims to investigate the effect of zinc supplementation on the anti-glycoxidation activity of carnosine on the in vitro model of albumin-based protein modification. Besides, the therapeutic effect of this combination was tested through the addition of the molecules in tandem (co-treatment) or post initiation (post-treatment) of the protein modification process. Glycation was induced via the addition of glucose to which carnosine (5 mM) alone or with various zinc concentrations (125, 250, and 500 mu M) were added either at 0 h or 24 h post-glycation induction. on the other hand, protein oxidation was induced using chloramine T (20 mM) and treated in the same way with carnosine and zinc. the different markers of glycation (advanced glycation end products (AGEs), dityrosine, and beta-sheet formation (aggregation)) and oxidation (AOPP, advanced oxidation protein products) were estimated via fluorescence and colorimetric assays. Zinc addition induced a significant enhancement of carnosine activity by reducing albumin modification that outperformed aminoguanidine both in the co- and post-treatment protocols. Zinc demonstrated a supplementary effect in combination with carnosine highlighting its potential in the protection against age-related protein modifications processes such as the ones found in diabetes