Mahmoud H. Othman

Mr. Mahmoud H. Othman

Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science, Wako, Japan
+3
orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
13 April 2022 in ACS Omega
Verified
Journal Article
Open access
NNNaveen Nagiah
Naveen Nagiah
RKRaven El Khoury
Raven El Khoury
MOMahmoud H. Othman
Mahmoud H. Othman
JAJun Akimoto
Jun Akimoto
YIYoshihiro Ito
Yoshihiro Ito
BJBinata Joddar
Binata Joddar
In this study, three types of electrospun scaffolds, including furfuryl-gelatin (f-gelatin) alone, f-gelatin with polycaprolactone (PCL) in a 1:1 ratio, and coaxial scaffolds with PCL (core) and f-gelatin (sheath), were developed for tissue engineering applications. Scaffolds were developed through single nozzle electrospinning and coaxial electrospinning, respectively, to serve as scaffolds for cardiac tissue engineering. Uniform fibrous structures were revealed in the scaffolds with significantly varying average fiber diameters of 760 ± 80 nm (f-gelatin), 420 ± 110 nm [f-gelatin and PCL (1:1)], and 810 ± 60 nm (coaxial f-gelatin > PCL) via scanning electron microscopy. The distinction between the core and the sheath of the fibers of the coaxial f-gelatin > PCL electrospun fibrous scaffolds was revealed by transmission electron microscopy. Thermal analysis and Fourier transformed infrared (FTIR) spectroscopy revealed no interactions between the polymers in the blended electrospun scaffolds. The varied blending methods led to significant differences in the elastic moduli of the electrospun scaffolds with the coaxial f-gelatin > PCL revealing the highest elastic modulus of all scaffolds (164 ± 3.85 kPa). All scaffolds exhibited excellent biocompatibility by supporting the adhesion and proliferation of human AC16 cardiomyocytes cells. The biocompatibility of the coaxial f-gelatin > PCL scaffolds with superior elastic modulus was assessed further through adhesion and functionality of human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes, thereby demonstrating the potential of the coaxially spun scaffolds as an ideal platform for developing cardiac tissue-on-a-chip models. Our results demonstrate a facile approach to produce visible light cross-linkable, hybrid, biodegradable nanofibrous scaffold biomaterials, which can serve as platforms for cardiac tissue engineered models.

19 November 2020 in Drug Development and Industrial Pharmacy
Verified
Journal Article
Closed access
MOMahmoud H. Othman
Mahmoud H. Othman
GZGamal M. Zayed
Gamal M. Zayed
UAUsama F. Ali
Usama F. Ali
Ahmed A. H. AbdellatifAhmed A. H. Abdellatif
Ahmed A. H. Abdellatif
Most anticancer medications undergo major first-pass metabolism in the intestinal wall, the liver, or both. 5-fluorouracil (5-FU) is known to have erratic oral bioavailability due to first-pass metabolism. The present study aimed to develop 5-FU-loaded microsponges (MS) compressed in enteric-coated tablets as a new colon targeting to colorectal cancer. MS was prepared as a controlled release system for 5-FU and characterized for drug encapsulation efficiency, and surface morphology. Further, hydroxypropyl methylcellulose (HPMC) was mixed with pectin and characterized for their flow as a tablet coat enclosing the core tablets of 5-FU-MS. Moreover, in vitro drug release behavior was studied in different pH media, while the X-ray imaging was used to monitor the in vivo movement of prepared tablets containing 5-FU-MS throughout the GI system. The results showed that MS were spherical in shape and have several pores on their surfaces. The encapsulation efficiency was from 71.80 ± 1.62% − 101.3 ± 2.60%, while the particle size was from 53.11 ± 41.03 − 118.12 ± 48.21 nm. The formulated tablets were fulfilling all official and other specifications and exhibited sustained release of 5-FU only inside the colon. The in vivo human volunteer study of X-ray has shown that the tablets ultimately reached the colon without disturbing in the upper GI system. The obtained carrier formulation is considered as a novel system to deliver 5-FU to the colon tumor with 100% targeting without any drug release in the upper GIT or first-pass metabolism.


10 October 2022 in ACS Macro Letters
Verified
Journal Article
Closed access
AMAhmed Fouad Abdelwahab Mohammed
Ahmed Fouad Abdelwahab Mohammed
MOMahmoud H. Othman
Mahmoud H. Othman
TTToru Taharabaru
Toru Taharabaru
KEKhaled M. Elamin
Khaled M. Elamin
KIKohzo Ito
Kohzo Ito
THTaishi Higashi
Taishi Higashi

13 December 2024 in Polymer Journal
Verified
Journal Article
Open access
PDF file
MOMahmoud H. Othman
Mahmoud H. Othman
YIYoshihiro Ito
Yoshihiro Ito
JAJun Akimoto
Jun Akimoto
Dynamic covalent bonds (DCBs) can be used as crosslinking points to induce self-healing and thermoplastic properties in hydrogels because the bonding and dissociation between molecules can be controlled by external stimuli. However, once DCBs dissociate, molecules diffuse inside the gel, delaying DCB reformation. In this study, a hydrogel was prepared via template polymerization using phenylboronic acid-coated nanoparticles to control the mobility of the molecules and the density of the DCB crosslinking points. Interestingly, the loss modulus, but not the storage modulus, of the hydrogel changed with temperature according to the formation/dissociation of boronic ester bonds. Furthermore, compared with conventional hydrogels, the hydrogels prepared here exhibited very rapid changes in physicochemical properties in response to changes in temperature because the high density of three-dimensional DCB crosslinking points limits the diffusion of molecules inside the gel. As a result, the prepared hydrogel showed rapid self-healing and thermoplastic properties as the temperature changed.

30 December 2022 in Polymers
Verified
Journal Article
Open access
PDF file
MOMahmoud H. Othman
Mahmoud H. Othman
YIYoshihiro Ito
Yoshihiro Ito
JAJun Akimoto
Jun Akimoto
Notably, antibiofouling is an important and predominant technique adopted to improve the surfaces of biomaterials. In this study, polyethylene glycol-grafted polyethylene glycols bearing azidophenyl groups were synthesized and immobilized on polystyrene surfaces via photoirradiation. The prepared polymers were found to be highly soluble in water, and photoimmobilization with fluorescent proteins was confirmed based on micropatterning using a photomask. These polymers suppressed nonspecific interactions between proteins and cells on the substrate. Considering that photoimmobilization can be adopted for the covalent bond modification of various surfaces, the developed water-soluble and highly antibiofouling polymers appear to be useful in biomaterial preparation.