Banca de DEFESA: JENNIFER NATHIELI DA SILVA ROTANDARO DE OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JENNIFER NATHIELI DA SILVA ROTANDARO DE OLIVEIRA
DATE: 10/03/2022
TIME: 09:00
LOCAL: Auditório do Instituto de Física (IF / UFAL)
TITLE:

INFLUENCES OF PROBE, SUBSTRATE AND
SURROUNDING MEDIUM ON ADHESION FORCE
CURVES BY AFM

KEY WORDS:

AFM, force curve, adhesion forces

PAGES: 64
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

In this work we use force curves obtained through the atomic force microscope (AFM) to
study the influence of probes, substrates and media on tip-substrate adhesions. The probes
HYDRA – 100NG, ACCESS – EFM and ACT – SS were used, whose tips are made of silicon (Si)
and silicon coated with Platinum (Pt). The experiments were carried out in three stages. In
the first step, we carried out experiments by interacting the probes on a glass substrate in
air, and, through the force curves obtained, it was observed that there was a greater
adhesion in the interaction of the HYDRA - 100NG and ACT -SS probes with Si tips. In the
second step, for each probe used, measurements of the interaction with two different
substrates were performed: glass and mica, in air. For this case, the AFM force curves
showed that the adhesion of the HYDRA – 100NG and ACT –SS probes on the mica
decreased while the adhesion on the mica of the probe with Pt coated tip, ACCESS – EFM,
increased. In the third stage of the experiment, for each probe and for each substrate,
measurements were carried out in air and in liquid, and in all the curves obtained, a
decrease in the adhesive force was observed in relation to the measurements made in air.
These results are important, since many studies using AFM need to know how the behavior
of adhesion forces in tip-substrate interactions, such as the functionalization of tips and
substrates for the construction of nanobiosensors based on AFM. And, as perspectives,
taking into account the results obtained, the next steps will be towards the fabrication of a
nanobiosensor based on AFM starting from the functionalization of a HYDRA - 100NG probe
and a mica substrate, performing measurements in liquid medium.

BANKING MEMBERS:
Presidente - 2928446 - SAMUEL TEIXEIRA DE SOUZA
Externa à Instituição - ELAINE CRISTINA OLIVEIRA DA SILVA
Externa à Instituição - GEOVANA DRESCH WEBLER