S146 Abstracts / New Biotechnology 44S (2018) S68–S164

immune responses. Protein-liposome conjugates are useful to real- P29-2

ize the concept of intrastructural help for vaccines against HIV.
Briefly, it is hypothesised that existing immunity against e.g. hep- Selection of ssDNA aptamers for the development of impedance
atitis B virus (HBV) or a childhood diseases such as measles can be biosensor to detect sarcosine
used to modulate the immune response towards an HIV vaccine
C. zyurt ∗ , Z. Çelik Canbay, U. Menglloglu, E. Dinçkaya, S. Evran
antigen. This can be done by encapsulating respective immun-
odominant T helper cell epitopes into liposomes which also present Department of Biochemistry, Faculty of Science, Ege University,
a HIV vaccine antigen on their surface. Conjugates of the viral enve- Izmir, Turkey
lope protein gp140 with liposomes encapsulating HBV peptides can
be taken up by naïve B-cells reactive to epitopes of gp140. B-cells Sarcosine is a potential prostate cancer biomarker that can be
then present peptides of HBV and gp140 on MHC-II molecules. Thus non-invasively analyzed in urine. Within the scope of this study,
T helper cells specific to HBV peptides can activate B-cells reactive sarcosine-specific DNA aptamers were selected using graphene
to gp140 epitopes. oxide-assisted systemic evolution of ligands by exponential enrich-
Utilising intrastructural help by using appropriate protein- ment (GO-SELEX). It was tested whether the developed aptamers
liposome conjugates could allow to imprint the characteristics of could be used in biosensor applications. For this purpose, 1 ␮M
the strong and robust immune response against HBV to that of HIV aptamer solution was first immobilized onto the gold electrode
envelope proteins. surface through the thiol group at it’s 5’-end for 17 h. Hence,
Acknowledgements: This project has received funding from self-assembled monolayer (SAM) was created. Subsequently, the
the European Union’s Horizon 2020 research and innovation pro- electrode was immersed into the 1 mM solution of 6-Mercapto-
gramme under grant agreement No. 681137. 1-hexanol (MCH) for blockage of the remaining gaps on the
https://doi.org/10.1016/j.nbt.2018.05.1124 gold surface. Finally, the immobilized aptamer was treated with
increasing concentrations (5.0 − 500 × 103 pM) of sarcosine. After
each step, the electrode surface was washed with the binding
buffer. Impedance and cyclic voltammetry measurements were
Diagnostic tools and biomarkers
performed. The success of each immobilization step and the con-
P29-1 centration of sarcosine were determined. A significant response to
sarcosine was obtained. Preliminary results show that the selected
Electrochemical impedance immunosensor for ferritin detec- aptamer is promising for biosensor applications. Further studies to
tion optimize and characterize the developed biosensor are in progress.
The authors would like to thank TUBITAK (The Scientific and
U. Mengulluoglu ∗ , E. Dinçkaya Technical Research Council of Turkey) for supporting this study
Department of Biochemistry, Faculty of Science, Ege University, with the project number 215Z182.
Izmir, Turkey https://doi.org/10.1016/j.nbt.2018.05.1126

Ferritin was discovered in 1937 by French scientist Laufberger

and isolated as a new protein from horse spleen. It is a ubiquitous P29-3
iron – binding protein which plays an important role in the storage
of intracellular iron. Ferritin is one of the most important markers Molecular diagnosis of FXS in Indian MR cases
of iron deficiency anemia, which is very common in human pop- S. Agarwal
ulations around the world. In addition, it is important as an acute
phase reactant in many cases of inflammation and in some cases SGPGIMS, Lucknow, India
as a tumor marker. Due to these important properties, sensitive
determination of serum ferritin levels is very important. Introduction: Fragile X Syndrome (FXS), the second most com-
In this study, a new impedimetric immunosensor for the mon type of X linked mental retardation (MR) is caused due to CGG
determination of ferritin was developed. As a basic principle, an repeat expansion mutation at FMR1 gene. The normal range CGG
affinity–based biosensor system based on antigen–antibody inter- repeat range is 6–44, gray zone range 45–54 repeats, premutation
action was developed and the impedance changes of the sensing range as 55–200 repeats and full mutation >200 repeats (affected).
surface were observed by electrochemical impedance spectroscopy PM alleles are unstable and can expand to FM in subsequent genera-
technique. Ferritin determination was carried out by way of the tion. Thus tracing these individuals holds significance in alleviating
mentioned changes. Antigen–antibody interaction was carried out the occurrence of FXS in the society and early diagnosis will help
between the anti-ferritin antibody and the ferritin biomolecules. in improving the quality of life of affected subjects.
The sensitivity of the immunosensor system has been increased as Objectives: Molecular characterization of FMRl gene in MR sub-
a result of various modifications of the sensor surfaces used. jects by using TP PCR technique and identify carriers in the family
Anti-ferritin antibodies were covalently immobilized onto the tree was done.
gold electrode surface via a self-assembled monolayer (SAM) of Method: Genomic DNA was extracted from 201 subjects (141
11 – mercaptoundecanoic acid (11 – MUA). Ferritin antigens were males and 12 females) with unexplained developmental delay,
detected by electrochemical impedance spectroscopy (EIS) as a intellectual disability and autism. TP-PCR amplification for FMR1
result of their interaction with surface-immobilized antibodies. allele is conducted and amplicons generated were subjected to
Optimization and characterization studies were carried out and the fragment analyses and results were documented.
linear range of the biosensor was from 2.5 to 400 pg/mL of ferritin. Results: Thirteen (6.46%) full mutation were identified in 201
MR suspects (186 males and 15 females). Genetic counselling was
https://doi.org/10.1016/j.nbt.2018.05.1125
given in all positive cases and family screening could be done in 9
of the full mutation males leading to identification of additional 15
PM (12 females and 1 males) 5 FM (1 females and 4 males) cases.