Temperature and pH-dependent behaviors of mAb drugs: A case study for trastuzumab

The distortions in the high-order structure of therapeutic monoclonal antibodies (mAbs) under different environmental conditions acutely affect mAb stability, resulting in altered safety, efficacy, and shelf-life profiles. The overall stability of mAbs depends on many factors, and it requires complementary techniques for an in-depth analysis. The stability of mAbs can be characterized by differential centrifugal sedimentation (DCS), differential scanning calorimetry (DSC), differential scanning fluorimetry (DSF), and size exclusion chromatography (SEC) techniques. In this report, temperature-ramped dynamic light scattering (DLS), and circular dichroism (CD) spectroscopy were employed as complementary tools to show how temperature and pH affect the aggregation of a model mAb, trastuzumab, in solution. The results showed that the aggregation onset temperature of trastuzumab defined by DLS was 75 degrees C, which decreases the amount of beta-sheets and causes a slight increase in helix structures. Moreover, the melting temperature of trastuzumab was determined to be between 80-83 degrees C by temperature-ramped CD spectrophotometry, which is in line with the Tm of trastuzumab's Fab region tested with DSC. Thus, unfolding and aggregation of trastuzumab start simultaneously at 75 degrees C, and unfolding triggers the aggregation. The temperature-ramped CD and DLS methods are robust tools to determine the thermal behavior of biosimilars in various solution conditions. Their complementary usage provides solid scientific background for regulatory applications and a better understanding of mAb instability and its relationship with structural changes

Plasmonic titanium nitride nanohole arrays for refractometric sensing

Group IVB metal nitrides have attracted great interest as alternative plasmonic materials. Among them, titanium nitride (TiN) stands out due to the ease of deposition and relative abundance of Ti compared to those of Zr and Hf metals. Even though they do not have Au or Ag-like plasmonic characteristics, they offer many advantages, from high mechanical stability to refractory behavior and complementary metal oxide semiconductor-compatible fabrication to tunable electrical/optical properties. In this study, we utilized reactive RF magnetron sputtering to deposit plasmonic TiN thin films. The flow rate and ratio of Ar/N2 and oxygen scavenging methods were optimized to improve the plasmonic performance of TiN thin films. The stoichiometry and structure of the TiN thin films were thoroughly investigated to assess the viability of the optimized operation procedures. To assess the plasmonic performance of TiN thin films, periodic nanohole arrays were perforated on TiN thin films by using electron beam lithography and reactive ion etching methods. The resulting TiN periodic nanohole array with varying periods was investigated by using a custom microspectroscopy setup for both reflection and transmission characteristics in various media to underline the efficacy of TiN for refractometric sensing.101111321 ; EP/Y030273/

INVESTIGATION OF THE PREDICTOR RELATIONSHIP BETWEEN THE ALTRUISM AND SELF-DIFFERENTIATION WITH SOME VARIABLES

Bu çalışmada, üniversite öğrencilerinin benlik ayrımlaşması ileözgecilik düzeyleri arasındaki ilişkileri belirlemek ve benlik ayrımlaşmadüzeyleri ile özgeciliğin demografik değişkenler açısından anlamlı birfarklılıkgösteripgöstermediğiniaraştırılmasıamaçlanmıştır.Araştırmanın örneklemi, bir devlet üniversitesinde okuyan 252öğrenciden (167 kadın, 85 erkek) oluşmaktadır. Araştırmada ölçmearacı olarak özgeci tutum, davranış ve düşünceleri içeren 15 maddedenoluşan Özgecilik Ölçeği; 20 maddeden oluşan ve “Duygusal tepkisellik(DT)”, “Ben pozisyonu alma (BP)”, “Duygusal kopma (DK)” ve“Başkalarına bağımlılık (BB)” olmak üzere dört alt boyuttan oluşanBenlik Ayrımlaşması Ölçeği kullanılmıştır. Ayrıca bağımsız değişkene aitveriler için kişisel bilgi formu kullanılmıştır. Araştırmanın bulgularınagöre, öğrencilerin cinsiyet ve akademik başarı düzeyi açısından özgecilikanlamlı düzeyde farklılık göstermektedir (p0.05). Cinsiyet değişkeniaçısından benlik ayrımlaşmasının bir boyutu olan duygusal tepkisellik;fakülte değişkeni açısından duygusal kopma boyutu; ailenin sosyo-ekonomik durumu değişkeni açısından ben pozisyonu alma boyutu;annenin eğitim durumu değişkeni açısından ise başkalarına bağımlılıkboyutlarında anlamlı farklılıklar gösterdiği görülmüştür(p0.05). Ayrıcaaraştırmaya katılan öğrencilerin benlik ayrımlaşması ile özgecilikdüzeyleri arasında pozitif yönde anlamlı bir ilişki olduğu saptanmıştır(sig. 0.050,047). Benlik ayrımlaşması düzeyi açısından ise öğrencilerindemografik özellikleri incelendiğinde cinsiyet, fakülte, ailenin sosyo ekonomik durumu ve anne eğitim durumu açısından anlamlı düzeydebir farklılık bulunurken; sınıf düzeyi, akademik başarı durumu ve babaeğitim durumu açısında anlamlı düzeyde bir farklılık bulunmamıştır.It was aimed in this study to determine the relationship betweenthe self-differentiation and altruism levels of university students andinvestigate whether there is a significant difference in the levels of self-differentiation and altruism levels in terms of demographic variables.The sample of the study consists of 252 students (167 female, 85 male)studying at a state university. The altruism scale including altruisticattitudes, behaviors and thoughts and consisting of 15 items, and theself-differentiation scale consisting of four sub-dimensions, were usedas measurement tools in the research. In addition, personal informationform was used for the data of independent variable. According to thefindings of the research, altruism of students differs significantly interms of gender and academic achievement level (p 0.05). It was foundthat there were significant differences in the emotional responsiveness,a dimension of differentiation of self in terms of gender variable and inthe dimension of emotional cutoff in terms of faculty variable.Additionally, there were significant differences in the dimension oftaking an "I" position in terms of the socio-economic status of the familyvariable, and in the dimension of co-dependency on others in terms ofeducation status of mother variable (p 0.05). Moreover, it was foundthat there was a positive significant relationship between thedifferentiation of self and altruism levels of the students participating inthe research (sig. 0.050.047). As for the self-differentiation level; whenthe demographic characteristics of the students were examined, whilethere were significant differences in terms of the gender, faculty, socio-economic status of the family and education level of the mother, therewas no significant difference in terms of grade level, academicachievement status and father education status

Bioconjugated materials: preparation, characterization and therapeutic applications

Currently, pharmaceutical research introduces bioconjugated structures along with nanoparticulate carrier technologies to overcome several limitations associated with existing drug delivery systems. Bioconjugation is a beneficial alternative to nanoparticle-based delivery systems in most cases due to its simple and generally one-step active ingredient conjugation processes and targeting abilities. In its simple description, bioconjugation involves the covalent attachment of two molecules to create a complex in which at least one of the molecules is a biomolecule, a derivative, or a fragment of a biomolecule. The conjugation process usually is done easily and, in most cases, controllable to form novel and useful complexes with multi-functions and preferred features. Antibody-drug conjugates (ADCs), aptamer−drug conjugates (ApDCs), and polymer-drug conjugates are among the most important bioconjugated structures with important therapeutic applications in the treatment of cancer. Conjugation aims to deliver toxic therapeutics to the intended cancerous cells with high efficacy while protecting healthy cells from the side effects of toxicity. This chapter presents an overview of the application of conjugated materials in therapeutics, drug delivery, and controlled release studies. First, bioconjugated structures and building blocks, processes, and reactions to prepare these materials, using representative examples, will be discussed. After a detailed description of synthesized bioconjugates' purification and characterization steps, we will focus on the precise structure of materials used in drug conjugation and drug release studies in the treatment of several disease including cancer

Plasmonic Titanium Nitride Nanohole Arrays for Refractometric Sensing.

Publication status: PublishedGroup IVB metal nitrides have attracted great interest as alternative plasmonic materials. Among them, titanium nitride (TiN) stands out due to the ease of deposition and relative abundance of Ti compared to those of Zr and Hf metals. Even though they do not have Au or Ag-like plasmonic characteristics, they offer many advantages, from high mechanical stability to refractory behavior and complementary metal oxide semiconductor-compatible fabrication to tunable electrical/optical properties. In this study, we utilized reactive RF magnetron sputtering to deposit plasmonic TiN thin films. The flow rate and ratio of Ar/N2 and oxygen scavenging methods were optimized to improve the plasmonic performance of TiN thin films. The stoichiometry and structure of the TiN thin films were thoroughly investigated to assess the viability of the optimized operation procedures. To assess the plasmonic performance of TiN thin films, periodic nanohole arrays were perforated on TiN thin films by using electron beam lithography and reactive ion etching methods. The resulting TiN periodic nanohole array with varying periods was investigated by using a custom microspectroscopy setup for both reflection and transmission characteristics in various media to underline the efficacy of TiN for refractometric sensing