The role of side chain of amino acid on performance of their conjugates with carboxymethyl cellulose and their Pd(II) complexes as bioactive agents

Lotfy, Vivian F.; Hassan, Safaa S.; Khalf‐Alla, Perihan A.; Basta, Altaf H.

doi:10.1080/00914037.2019.1670179

Cited by 30 publications

(9 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 and 5, in comparison with bleached solvent‐extracted RS (Ex). The more appropriate order of degradation n of these samples and their activation energy E a of the main degradation stage are estimated according to the following equations 46 and mentioned in Tabs. 4 and 5.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Essential Role of Pulping Route on Thermal Stability Performance of Rice Straw‐Based Nanocelluloses

Basta

Lotfy

2023

Chem Eng & Technol

Self Cite

View full text Add to dashboard Cite

There is a strong interest in production of thermally stable nanocelluloses for further applications. Despite the enormous success achieved in preparing cellulose nanocrystals (CNCs) by acid catalyst technique, these products remain a major challenge due to the lack of thermal stability which till now could not be solved. This work deals with assessing the role of alkali, neutral, acid, and organosolvent pulping agents on thermal stability performances of produced rice straw (RS)‐based CNCs. This property was estimated by thermogravimetric analysis. The data obtained indicated that employing a pulping to RS > 4.75 mm with sodium hydroxide in the presence of anthraquinone‐sodium borohydride can help address these challenges by providing CNCs with highest activation energy as well as a lower aspect length‐to‐width ratio according to transmission electron microscopy images.

show abstract

Section: Resultsmentioning

confidence: 99%

“…All measurements were achieved over the temperature range of 30-800 °C using a heating scan rate of 10 °C min -1 in an inert atmosphere of nitrogen gas (30 mL min -1 ). The activation energies (E a ) of the main degradation stage of all investigated samples were estimated according to [44][45][46].…”

Section: Non-isothermal Thermogravimetric Analysismentioning

confidence: 99%

Essential Role of Pulping Route on Thermal Stability Performance of Rice Straw‐Based Nanocelluloses

Basta

Lotfy

2023

Chem Eng & Technol

Self Cite

View full text Add to dashboard Cite

show abstract

“…These complexes have demonstrated effective cytotoxicity. [11,12] In extension to our previous papers that show the potent anticancer activity of the Pd complexes against various cancer cell lines, [13][14][15][16][17] we chelate the new amoxicillin-based compound with palladium ion to form a new expected highly anticancer compound.…”

Section: Introductionmentioning

confidence: 99%

The double‐edged sword of the amoxicillin antibiotic against prostate cancer in nano palladium form and its electrochemical detection of dopamine

Hassan

Hanna

Medany

2023

Applied Organom Chemis

View full text Add to dashboard Cite

Pd (II) complex was prepared from the interaction with Schiff base based on the condensation amoxicillin trihydrate drug and 4-N,N-dimethylaminobenzaldehyde. The complex was prepared on the nanoscale that was investigated using transmission electron microscopy (TEM). The chemical structure of the synthesized Schiff base and its Pd (II) chelate was proved through several techniques. Assays using MTT and lactate dehydrogenase verified the Pd (II) complex ability to inhibit human prostate cancer cells (PC3). According to the findings, the inhibition of PC3 cell growth was directly proportional to the dose of Pd (II) complex. Its highest IC 50 value was attained after 48 h of incubation reached to 22.6 μg/mL. As a measure of DNA damage in PC3 cells, this IC50 value demonstrated a significant increase in early and late apoptotic cells with an intense comet nucleus. Given that the concentration of reactive oxygen species (ROS) in treated PC3 cells was much higher than in control ones. These results contributed to the notion that ROS-mediated cell death, which may have taken place via the mitochondrial pathway, was the mechanism by which the Pd (II) complex inhibited the proliferation of PC3 cancer cells. The prepared Pd (II) complex was fabricated and casted onto GC electrode for investigate the dopamine concentration in human serum. The limit of detection and limit of quantization were found to be 0.0127 and 0.0424 μM, respectively, which were in a good agreement with literature and were found to be an improvement to that present in the literature.

show abstract

“…The functionalized paper, carbon nanostructures materials, semiconductor, water purification adsorbent, liquid crystal materials and the formaldehyde-free adhesive are literature applications for the cellulose-based products (Hosny et al , 1997; Vimala et al , 2009; Thakur et al , 2013; El-Saied et al , 2016; Canejo et al , 2017; Lotfy et al , 2018; Ravichandran et al , 2018; Basta et al , 2011, 2013, 2014, 2019; Ates et al , 2020). Additionally, there are medical and agriculture applications for the cellulose and its derivatives which are produced in form of hydrogel formulation (Lotfy and Basta, 2020; Lotfy et al , 2020; Hanna et al , 2020; Khalf-Alla et al , 2020; Basta et al , 2020, 2021a, 2021b, 2021c, 2021d, 2021e; Basta and Lotfy, 2021).…”

Section: Introductionmentioning

confidence: 99%

Selective route for enhancing liquid crystal-based hydroxylpropyl cellulose by esterification

Basta

Lotfy

Micky

et al. 2022

PRT

View full text Add to dashboard Cite

Purpose This paper aims to study the effect of hydrolysis route of hydroxypropyl cellulose (HPC) on its esterification performance as liquid crystal material. The assessment was carried out from the data of spectra (Fourier-transform infrared analysis [FTIR] and 1H-nuclear magnetic resonance [1H-NMR]), thermal stability as well as optical properties via forming ordered mesophases at lower concentration than HPC. Design/methodology/approach The HPC was hydrolyzed by hydrochloric acid-methanol at times 9 and 18 h, and the products were esterified by decanoyl chloride. The products of hydrolysis and the esterification were characterized by FTIR, NMR, nonisothermal analysis, thermo-gravimetric analysis (TGA) and polarizing microscope to evaluate the role of degree of substitution of HPC as a result of hydrolysis, on esterification degree, thermal stability and thermal and liquid crystal behavior of the final esterified HPC. Findings The pretreatment by acid hydrolysis of HPC was successful for synthesizing novel cholesteric hydroxypropyl cellulose ester. The data of FTIR and TGA thermal analysis proved that hydrolysis and esterification of HPC with the decanoyl chain significantly enhanced crystallinity of this cellulose derivative from 0.57 to (1.7–1.9). Moreover, they provided products with superior thermal stability than pure HPC, as noticed from increasing the activation energy of degradation (Ea) from 514.3 to 806.2 kJ/mol. The NMR measurement proved that hydrolysis of HPC for 9 and 18 h decreased the degree of substitution from 3 to 2.1 and 1.3, respectively. Moreover, the esterified HPC showed a promising birefringence texture (chiral nematic) besides decreasing the critical concentration from 30% for HPC to 10% for the esterified unhydrolyzed HPC, while superior decreasing to 1–5% was observed for the esterified hydrolyzed HPC. Research limitations/implications There are two stages for preparation of decanoyl ester hydroxypropyl cellulose. At the first stage, HPC was treated by hydrochloric acid-methanol in ratio 1:10 at times 9 and18 h. At the second stage, HPC and hydrolyzed HPC were refluxed with decanoyl chloride (1:6) in presence of nitrogen atmosphere. The final product was precipitated by distilled water. Practical implications There are two stages for preparation of decanoyl ester hydroxypropyl cellulose. At the first stage, HPC was treated by hydrochloric acid-methanol in ratio 1:10 at times 9 and18 h. At the second stage, HPC and hydrolyzed HPC were refluxed with decanoyl chloride (1:6) in presence of nitrogen atmosphere. The final product was precipitated by distilled water. Originality/value The novelty of this work was focused on enhancing the crystallinity, thermal stability and liquid crystal behavior of esterified HPC, via decreasing the degree of substitution and consequently the type of OH group subjected to esterification. The decanoyl ester formation from the hydrolyzed hydroxypropyl cellulose is able to form ordered mesophases at even low concentration (promising birefringence texture at concentrations 1–5%). It is worthy to notice that the investigated route is able to omit the role of graphene oxide in promoting the liquid crystal behavior of HPC, as it hasn't any effect on critical concentration. This work will promote the use of HPC in technological applications, e.g. high modulus fibers and electronic devices.

show abstract

The role of side chain of amino acid on performance of their conjugates with carboxymethyl cellulose and their Pd(II) complexes as bioactive agents

Cited by 30 publications

References 38 publications

Essential Role of Pulping Route on Thermal Stability Performance of Rice Straw‐Based Nanocelluloses

Essential Role of Pulping Route on Thermal Stability Performance of Rice Straw‐Based Nanocelluloses

The double‐edged sword of the amoxicillin antibiotic against prostate cancer in nano palladium form and its electrochemical detection of dopamine

Selective route for enhancing liquid crystal-based hydroxylpropyl cellulose by esterification

Contact Info

Product

Resources

About