scholarly journals Synthesis, Characterisation and Biological Evaluation of Ampicillin–Chitosan–Polyanion Nanoparticles Produced by Ionic Gelation and Polyelectrolyte Complexation Assisted by High-Intensity Sonication

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1758 ◽  
Author(s):  
Ciro ◽  
Rojas ◽  
Salamanca
Keyword(s):  
Zeta Potential ◽  
Maleic Acid ◽  
High Intensity ◽  
Antimicrobial Effect ◽  
Fold Increase ◽  
Biological Evaluation ◽  
Resistant Bacteria ◽  
Ionic Gelation ◽  
Polyelectrolyte Complexation ◽  
Broth Microdilution Method

Recently, one of the promising strategies to fight sensitive and resistant bacteria, and decrease the morbidity and mortality rates due to non-nosocomial infections, is to use antibiotic-loaded nanoparticles. In this study, ampicillin-loaded chitosan–polyanion nanoparticles were produced through the techniques of ionic gelation and polyelectrolyte complexation assisted by high-intensity sonication, using several crosslinking agents, including phytic acid (non-polymeric polyanion), sodium and potassium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene) (polymeric polyanions). These nanoparticles were analysed and characterised in terms of particle size, polydispersity index, zeta potential and encapsulation efficiency. The stability of these nanosystems was carried out at temperatures of 4 and 40 °C, and the antimicrobial effect was determined by the broth microdilution method using sensitive and resistant Staphylococcus aureus strains. The results reveal that most of the nanosystems have sizes <220 nm, positive zeta potential values and a monodisperse population, except for the nanoparticles crosslinked with PAM-18 polyanions. The nanometric systems exhibited adequate stability preventing aggregation and revealed a two-fold increase in antimicrobial activity when compared with free ampicillin. This study demonstrates the potential application of synthesised nanoparticles in the field of medicine, especially for treating infections caused by pathogenic S. aureus strains.

scholarly journals Production and Characterization of Chitosan–Polyanion Nanoparticles by Polyelectrolyte Complexation Assisted by High-Intensity Sonication for the Modified Release of Methotrexate

2020 ◽  
Vol 13 (1) ◽  
pp. 11 ◽  
Author(s):  
Yhors Ciro ◽  
John Rojas ◽  
Maria Alhajj ◽  
Gustavo Carabali ◽  
Constain Salamanca
Keyword(s):  
Zeta Potential ◽  
Maleic Acid ◽  
High Intensity ◽  
Physical Stability ◽  
Release Mechanism ◽  
Diffusion Controlled ◽  
Polyelectrolyte Complexation ◽  
Anticancer Treatment ◽  
Particle Parameters

A promising strategy to improve the effectivity of anticancer treatment and decrease its side effects is to modulate drug release by using nanoparticulates (NPs) as carriers. In this study, methotrexate-loaded chitosan–polyanion nanoparticles were produced by polyelectrolyte complexation assisted by high-intensity sonication, using several anionic polymers, such as the sodium and potassium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene), here named PAM-2 and PAM-18, respectively. Such NPs were analyzed and characterized according to particle size, polydispersity index, zeta potential and encapsulation efficiency. Likewise, their physical stability was tested at 4 °C and 40 °C in order to evaluate any change in the previously mentioned particle parameters. The in vitro methotrexate release was assessed at a pH of 7.4, which simulated physiological conditions, and the data were fitted to the heuristic models of order one, Higuchi, Peppas–Sahlin and Korsmeyer–Peppas. The results revealed that most of the MTX-chitosan–polyanion NPs have positive zeta potential values, sizes <280 nm and monodisperse populations, except for the NPs formed with PAM-18 polyanions. Further, the NPs showed adequate physical stability, preventing NP–NP aggregation. Likewise, these carriers modified the MTX release by an anomalous mechanism, where the NPs formed with PAM-2 polymer led to a release mechanism controlled by diffusion and relaxation, whereas the NPs formed with PAM-18 led to a mainly diffusion-controlled release mechanism.

scholarly journals α-Terpinyl Acetate: Occurrence in Essential Oils Bearing Thymus pulegioides, Phytotoxicity, and Antimicrobial Effects

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1065
Author(s):  
Vaida Vaičiulytė ◽  
Kristina Ložienė ◽  
Jurgita Švedienė ◽  
Vita Raudonienė ◽  
Algimantas Paškevičius
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Poa Pratensis ◽  
Antimicrobial Effect ◽  
Forage Legume ◽  
Economic Productivity ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Phytotoxic Effect ◽  
Lower Effect

The aim of this study was to evaluate occurrence of T. pulegioides α-terpinyl acetate chemotype, as source of natural origin α-terpinyl acetate, to determine its phytotoxic and antimicrobial features. Were investigated 131 T. pulegioides habitats. Essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. Phytotoxic effect of essential oil of this chemotype on monocotyledons and dicotyledons through water and air was carried out in laboratory conditions; the broth microdilution method was used to screen essential oil effect against human pathogenic microorganisms. Results showed that α-terpinyl acetate was very rare compound in essential oil of T. pulegioides: it was found only in 35% of investigated T. pulegioides habitats. α-Terpinyl acetate (in essential oil and pure) demonstrated different behavior on investigated plants. Phytotoxic effect of α-terpinyl acetate was stronger on investigated monocotyledons than on dicotyledons. α-Terpinyl acetate essential oil inhibited seeds germination and radicles growth for high economic productivity forage grass monocotyledon Poa pratensis, but stimulated seed germination for high economic productive forage legume dicotyledon Trifolium pretense. α-Terpinyl acetate essential oil showed high antimicrobial effect against fungi and dermatophytes but lower effect against bacteria and Candida yeasts. Therefore, T. pulegioides α-terpinyl acetate chemotype could be a potential compound for developing preventive measures or/and drugs for mycosis.

scholarly journals FORMULATION AND CHARACTERIZATION OF TIMOLOL MALEATE-LOADED NANOPARTICLES GEL BY IONIC GELATION METHOD USING CHITOSAN AND SODIUM ALGINATE

2019 ◽  
pp. 48-54 ◽  
Author(s):  
RISA AHDYANI ◽  
LARAS NOVITASARI ◽  
RONNY MARTIEN
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Polydispersity Index ◽  
Ionic Gelation ◽  
Timolol Maleate ◽  
Optimum Formula

Objective: The objectives of this study were to formulate and characterize nanoparticles gel of timolol maleate (TM) by ionic gelation method using chitosan (CS) and sodium alginate (SA). Methods: Optimization was carried out by factorial design using Design Expert®10.0.1 software to obtain the concentration of CS, SA, and calcium chloride (CaCl2) to produce the optimum formula of TM nanoparticles. The optimum formula was characterized for particle size, polydispersity index, entrapment efficiency, Zeta potential, and molecular structure. Hydroxy Propyl Methyl Cellulose (HPMC) K15 was incorporated into optimum formula to form nanoparticles gel of TM and carried out in vivo release study using the Franz Diffusion Cell. Results: TM nanoparticles was successfully prepared with concentration of CS, SA, and CaCl2 of 0.01 % (w/v), 0.1 % (w/v), and 0.25 % (w/v), respectively. The particle size, polydispersity index, entrapment efficiency, and Zeta potential were found to be 200.47±4.20 nm, 0.27±0.0154, 35.23±4.55 %, and-5.68±1.80 mV, respectively. The result of FTIR spectra indicated TM-loaded in the nanoparticles system. In vitro release profile of TM-loaded nanoparticles gel showed controlled release and the Korsmeyer-Peppas model was found to be the best fit for drug release kinetics. Conclusion: TM-loaded CS/SA nanoparticles gel was successfully prepared and could be considered as a promising candidate for controlled TM delivery of infantile hemangioma treatment.

scholarly journals Structure-Based Virtual Screening and Biological Evaluation of Peptide Inhibitors for Polo-Box Domain

Molecules ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 107 ◽  
Author(s):  
Fang Yan ◽  
Guangmei Liu ◽  
Tingting Chen ◽  
Xiaochen Fu ◽  
Miao-Miao Niu
Keyword(s):  
Cell Cycle ◽  
Virtual Screening ◽  
Fold Increase ◽  
Pharmacophore Modeling ◽  
Biological Evaluation ◽  
Peptide Inhibitors ◽  
Regulatory Proteins ◽  
Competitive Binding Assay ◽  
M Phase ◽  
Cell Cycle Regulatory Proteins

The polo-box domain of polo-like kinase 1 (PLK1-PBD) is proved to have crucial roles in cell proliferation. Designing PLK1-PBD inhibitors is challenging due to their poor cellular penetration. In this study, we applied a virtual screening workflow based on a combination of structure-based pharmacophore modeling with molecular docking screening techniques, so as to discover potent PLK1-PBD peptide inhibitors. The resulting 9 virtual screening peptides showed affinities for PLK1-PBD in a competitive binding assay. In particular, peptide 5 exhibited an approximately 100-fold increase in inhibitory activity (IC50 = 70 nM), as compared with the control poloboxtide. Moreover, cell cycle experiments indicated that peptide 5 effectively inhibited the expression of p-Cdc25C and cell cycle regulatory proteins by affecting the function of PLK1-PBD, thereby inducing mitotic arrest at the G2/M phase. Overall, peptide 5 can serve as a potent lead for further investigation as PLK1-PBD inhibitors.

Design, Synthesis, and Biological Evaluation of 4-Alkyliden-beta Lactams:  New Products with Promising Antibiotic Activity Against Resistant Bacteria

2006 ◽  
Vol 49 (9) ◽  
pp. 2804-2811 ◽  
Author(s):  
Francesco Broccolo ◽  
Gianfranco Cainelli ◽  
Gianluigi Caltabiano ◽  
Clementina E. A. Cocuzza ◽  
Cosimo G. Fortuna ◽  
...  
Keyword(s):  
New Products ◽  
Biological Evaluation ◽  
Antibiotic Activity ◽  
Resistant Bacteria ◽  
Beta Lactams ◽  
Design Synthesis ◽  
Synthesis And Biological Evaluation

scholarly journals Physicochemical and Biological Evaluation of Endodontic Filling Materials for Primary Teeth

2017 ◽  
Vol 28 (5) ◽  
pp. 578-586 ◽  
Author(s):  
Katerine Jahnecke Pilownic ◽  
Ana Paula Neutzling Gomes ◽  
Zhe Jun Wang ◽  
Luiza Helena Silva Almeida ◽  
Ana Regina Romano ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Cell Viability ◽  
Primary Teeth ◽  
Antimicrobial Effect ◽  
Biological Evaluation ◽  
In Vivo Studies ◽  
Filling Materials ◽  
Histological Data ◽  
Biocompatibility Test

Abstract This study assessed the pH, radiopacity, antimicrobial effect, cytotoxicity and biocompatibility of endodontic filling materials for primary teeth. Zinc oxide eugenol (ZOE), Vitapex and Calen paste thickened with zinc oxide (ZO) were evaluated in comparison to an experimental MTA-based material. Radiopacity was tested using a graduated aluminum stepwedge with a digital sensor (n=5). The materials pH was recorded at 1, 4, 12 h; 1, 3, 7, 15 and 30 days (n=5). Direct contact test was used to assess the antimicrobial efficacy against Enterococcus faecalis after 1, 4, 12, 24 h (n=5). Cytotoxicity assay used MTT test for cell viability after incubation for 1, 3 and 7 days (n=5). For biocompatibility test, Wistar rats had received implants containing each material (n=5). The biopsied tissues were histologically analyzed after 15, 30 and 60 days. The results of radiopacity, pH, antimicrobial capacity and cytotoxicity were analyzed using ANOVA and Tukey tests. The histological data were submitted to Kruskal-Wallis test. The experimental material presented the lowest radiopacity (3.28 mm Al) and had a pH>12.0 throughout the test period. The experimental material showed the highest antibacterial effect, killing over 99.97% bacteria in 4 h. Vitapex presented the highest cell viability. Initially, biocompatibility test showed moderate to severe inflammation in all groups. After 60 days, Calen+ZO group showed moderate inflammation, while the others showed predominantly mild inflammatory reaction. The present results demonstrated that the experimental MTA-based material exhibited satisfactory behavior regarding the studied properties. Additional in vivo studies are necessary for a better evaluation of the material.

scholarly journals SYNTHESIS OF ENCAPSULATED CHROMOLAENA ODORATA LEAF EXTRACT IN CHITOSAN NANOPARTICLE BY USING IONIC GELATION METHOD AND ITS ANTIOXIDANT ACTIVITY

2021 ◽  
pp. 112-115
Author(s):  
KENI IDACAHYATI ◽  
WINDA TRISNA WULANDARI ◽  
FIRMAN GUSTAMAN AND INDRA INDRA
Keyword(s):  
Antioxidant Activity ◽  
Zeta Potential ◽  
Leaf Extract ◽  
Crosslinking Agent ◽  
Average Diameter ◽  
Ionic Gelation ◽  
Chromolaena Odorata ◽  
Dpph Method ◽  
Chitosan Nanoparticle

Objective: The aim of this study was to determine the antioxidant activity of Chromolaena odorata. Methods: Encapsulation of Chromolaena odorata leaf extract by nano chitosan was synthesized by using chitosan and NaTPP as the crosslinking agent. The antioxidant activity was conducted by using the DPPH method. Results: Nanoparticles of Chromolaena odorata leaf extract has an average diameter of 675±218 nm and+23.4±7.14 mV of zeta potential. The antioxidant activity of its extract was 0.86 ppm, while its nanoparticle has the better antioxidant activity of 0.21 ppm. Conclusion: Nanoparticles of Chromolaena odorata have very strong antioxidant activity and the potential to be external antioxidants.

Synthesis and Antibacterial Activities of Amidine Substituted Monocyclic β-Lactams

2021 ◽  
Vol 17 ◽  
Author(s):  
Lijuan Zhai ◽  
Lili He ◽  
Yuanbai Liu ◽  
Ko Ko Myo ◽  
Zafar Iqbal ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Bacterial Species ◽  
Antimicrobial Effect ◽  
Antibacterial Activities ◽  
Lead Target ◽  
Bacterial Strains ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Clinical Interest

Background: Mononcyclic β-lactams are regarded as the most resistant class of β-lactams against a series of β-lactamases though possess limited antibacterial activity. Aztreonam being the first clinically approved monobactam needs broad-spectrum efficacy through structural modification. Objective: We strive to synthesize a number of monocyclic β-lactams by varying the substituents at N1, C3 and C4 positions of azetidinone ring and study the antimicrobial effect on variable bacterial strains. Methods: Seven new monobactam derivatives 23a-g, containing substituted-amidine moieties linked to the azetidinone ring via thiazole linker, were synthesized through multistep synthesis. The final compounds were investigated for their in vitro antibacterial activities using broth microdilution method, against ten bacterial strains of clinical interest. The minimum inhibitory concentrations (MICs) of newly synthesized derivatives were compared with aztreonam, ceftazidime and meropenem, existing clinical antibiotics. Results: All compounds 23a-g showed higher antibacterial activities (MIC 0.25 µg/mL to 64 µg/mL) against tested strains as compared to aztreonam (MIC 16 µg/mL to >64 µg/mL) and ceftazidime (MIC >64 µg/mL). However all compounds, except 23d, exhibited lower antibacterial activity against all tested bacterial strains as compared to meropenem. Conclusion: Compound 23d showed comparable or improved antibacterial activity (MIC 0.25 µg/mL to 2 µg/mL) to meropenem (MIC 1 µg/mL to 2 µg/mL) in case of seven bacterial species. Therefore, compound 23d may be valuable lead target for further investigations against multi-drug resistant Gram-negative bacteria.

Ampicillin-augmented silver nanoparticles for synergistic antimicrobial response: A promising therapeutic approach

2021 ◽  
Vol 22 ◽  
Author(s):  
Kashan Khan ◽  
Mohd Aamir Qureshi ◽  
Ameer Azam ◽  
Moinuddin ◽  
Javed Musarrat ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Silver Nanoparticles ◽  
Zeta Potential ◽  
Bacterial Infections ◽  
Colloidal Stability ◽  
Resistant Bacteria ◽  
Antimicrobial Drugs ◽  
Vis Spectroscopy ◽  
Microbial Infections ◽  
Ft Ir

Aims: Globally Scientists are working to find more efficient antimicrobial drugs to treat microbial infections and kill drug-resistant bacteria. Background: Despite the availability of numerous antimicrobial drugs bacterial infections still poses a serious threat to global health. Due to a constant decline in the effectiveness of antibiotics owing to their repeated exposure as well as shortlasting antimicrobial activity, led to the demand for developing novel therapeutic agents capable of controlling microbial infections. Objective: In this study, we report antimicrobial activity of chemically synthesized silver nanoparticles (cAgNPs) augmented with ampicillin (amp) in order to increase antimicrobial response against Escherichia coli (gram –ve), Staphylococcus aureus (gram +ve) and Streptococcus mutans (gram +ve). Methods: Nanostructure, colloidal stability, morphology and size of cAgNPs before and after functionalization were explored by UV-vis spectroscopy, FT-IR, zeta potential and TEM. The formation and functionalization of cAgNPs was confirmed from UV-vis spectroscopy and FT-IR patterns. From TEM the average sizes of cAgNPs and cAgNP-amp were found to be 13 and 7.8 nm respectively, and change in colloidal stability after augmentation was confirmed from zeta potential values. The antimicrobial efficacies of cAgNP-amp and cAgNPs against E. coli S. aureus and S. mutans were studied by determining minimum inhibitory concentrations (MICs), zone of inhibition, assessment of viable and non-viable bacterial cells and quantitative assessment of biofilm. Results & Discussion: Our results revealed cAgNP-amp to be highly bactericidal compared to cAgNPs or amp alone. The nano-toxicity studies indicated cAgNP-amp to be less toxic compared to cAgNPs alone. Results: This study manifested that cAgNPs show synergistic antimicrobial effect when they get functionalized with amp suggesting their application in curing long-term bacterial infections.

Sign in / Sign up

Export Citation Format

Share Document