scholarly journals Effect of Crystallinity on the Properties of Polycaprolactone Nanoparticles Containing the Dual FLAP/mPEGS-1 Inhibitor BRP-187

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2557
Author(s):  
Antje Vollrath ◽  
Christian Kretzer ◽  
Bärbel Beringer-Siemers ◽  
Blerina Shkodra ◽  
Justyna A. Czaplewska ◽  
...  
Keyword(s):  
Enzymatic Degradation ◽  
Drug Loading ◽  
Degree Of Crystallinity ◽  
Copolymer Composition ◽  
Vis Spectroscopy ◽  
Bulk Polymers ◽  
Formulation Parameters ◽  
Human Polymorphonuclear Leukocytes ◽  
In Vitro Performance

Seven polycaprolactones (PCL) with constant hydrophobicity but a varying degree of crystallinity prepared from the constitutional isomers ε-caprolactone (εCL) and δ-caprolactone (δCL) were utilized to formulate nanoparticles. The aim was to investigate the effect of the crystallinity of the bulk polymers on the enzymatic degradation of the particles. Furthermore, their efficiency to encapsulate the hydrophobic anti-inflammatory drug BRP-187 and the final in vitro performance of the resulting NPs were evaluated. Initially, high-throughput nanoprecipitation was employed for the εCL and δCL homopolymers to screen and establish important formulation parameters (organic solvent, polymer and surfactant concentration). Next, BRP-187-loaded PCL nanoparticles were prepared by batch nanoprecipitation and characterized using dynamic light scattering, scanning electron microscopy and UV-Vis spectroscopy to determine and to compare particle size, polydispersity, zeta potential, drug loading as well as the apparent enzymatic degradation as a function of the copolymer composition. Ultimately, NPs were examined for their potency in vitro in human polymorphonuclear leukocytes to inhibit the BRP-187 target 5-lipoxygenase-activating protein (FLAP). It was evident by Tukey’s multi-comparison test that the degree of crystallinity of copolymers directly influenced their apparent enzymatic degradation and consequently their efficiency to inhibit the drug target.

scholarly journals Chitosan/poly(lactic-co-glycolic)acid Nanoparticle Formulations with Finely-Tuned Size Distributions for Enhanced Mucoadhesion

Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 95
Author(s):  
Feipeng Yang ◽  
Maleen Cabe ◽  
Hope A. Nowak ◽  
Kelly A. Langert
Keyword(s):  
Drug Delivery ◽  
Aqueous Phase ◽  
Glycolic Acid ◽  
Drug Loading ◽  
Delivery Systems ◽  
Intranasal Delivery ◽  
Brain Drug Delivery ◽  
Size Groups ◽  
Formulation Parameters

Non-parenteral drug delivery systems using biomaterials have advantages over traditional parenteral strategies. For ocular and intranasal delivery, nanoparticulate systems must bind to and permeate through mucosal epithelium and other biological barriers. The incorporation of mucoadhesive and permeation-enhancing biomaterials such as chitosan facilitate this, but tend to increase the size and polydispersity of the nanoparticles, making practical optimization and implementation of mucoadhesive nanoparticle formulations a challenge. In this study, we adjusted key poly(lactic-co-glycolic) acid (PLGA) nanoparticle formulation parameters including the organic solvent and co-solvent, the concentration of polymer in the organic phase, the composition of the aqueous phase, the sonication amplitude, and the inclusion of chitosan in the aqueous phase. By doing so, we prepared four statistically unique size groups of PLGA NPs and equally-sized chitosan-PLGA NP counterparts. We loaded simvastatin, a candidate for novel ocular and intranasal delivery systems, into the nanoparticles to investigate the effects of size and surface modification on drug loading and release, and we quantified size- and surface-dependent changes in mucoadhesion in vitro. These methods and findings will contribute to the advancement of mucoadhesive nanoformulations for ocular and nose-to-brain drug delivery.

Proteome Mediated Synthesis of Biocompatible Green Fluorescence Cerium Oxide Quantum Dots with Enhanced Antioxidant Activity

2020 ◽  
Vol 12 (6) ◽  
pp. 831-839
Author(s):  
Amita A. Bhagit ◽  
Sveeta V. Mhatre ◽  
R. P. Yadav
Keyword(s):  
Quantum Dots ◽  
Antioxidant Activity ◽  
Band Gap ◽  
Cerium Oxide ◽  
Bulk Material ◽  
Degree Of Crystallinity ◽  
Light Quantum ◽  
Vis Spectroscopy

Biocompatibility of quantum dots make good candidature for in vivo and in vitro diagnostic applications. In this study biocompatible cerium oxide quantum dots (CeO2 QDs) were synthesized from proteome of Justicia adhatoda leaf using simple aqueous protocol. Synthesized cerium oxide nanoparticle possessed green colored fluorescence under UV light. Quantum yield of CeO2 QDs was found to be 31.13% and were stable for 3 month at 4 °C. The band gap was found to be 3.26 eV which was higher than the band gap of bulk material i.e., 3.19 eV. The concentration of synthesized CeO2 QDs was determined as 165.96 ppm. These quantum dots were also characterized using an UV-Vis spectroscopy, Fourier Transform Infra-red Spectroscopy (FT-IR) and Transmission Electron Microscopy (TEM) respectively. It displayed distinct absorbance peak at 380 nm under UV-Visible spectrum. TEM images showed monodispersity of 2–5 nm spherical shaped CeO2 QDs and higher degree of crystallinity was observed by the pattern of selected area electron diffraction. In FTIR, the stretching observed at 621.65 cm–1 is assigned to Ce-O which confirmed the CeO2QDs formation. In view of biocompability, synthesized CeO2QDs were also characterised in reference to cell toxicity. Generated CeO2QDs has not showed any toxicity to J774A.1, Raw 264.7 and 3T3 cell lines in vitro cell viability assay. Significant enhancement in antioxidant activity of synthesized cerium oxide nanoparticles was observed from bulk material. This process offers plenty of advantages such as simple protocol, mild environment operation, potential for large scale commercial production of biocompatible CeO2QD. These QDs might find potential applications in both in vitro and in vivo diagnostics.

Influence of drug loading and type of ointment base on the in vitro performance of acyclovir ophthalmic ointment

2015 ◽  
Vol 495 (2) ◽  
pp. 783-791 ◽  
Author(s):  
Manar Al-Ghabeish ◽  
Xiaoming Xu ◽  
Yellela S.R. Krishnaiah ◽  
Ziyaur Rahman ◽  
Yang Yang ◽  
...  
Keyword(s):  
Drug Loading ◽  
Ophthalmic Ointment ◽  
Ointment Base ◽  
In Vitro Performance

scholarly journals Microbial and Enzymatic Degradation of Synthetic Plastics

2020 ◽  
Vol 11 ◽  
Author(s):  
Nisha Mohanan ◽  
Zahra Montazer ◽  
Parveen K. Sharma ◽  
David B. Levin
Keyword(s):  
Microbial Degradation ◽  
Enzymatic Degradation ◽  
Polymer Surface ◽  
Amorphous Region ◽  
Degree Of Crystallinity ◽  
Crystalline Region ◽  
Molecular Weights ◽  
Chemical Structures ◽  
Lower Temperature

Synthetic plastics are pivotal in our current lifestyle and therefore, its accumulation is a major concern for environment and human health. Petroleum-derived (petro-)polymers such as polyethylene (PE), polyethylene terephthalate (PET), polyurethane (PU), polystyrene (PS), polypropylene (PP), and polyvinyl chloride (PVC) are extremely recalcitrant to natural biodegradation pathways. Some microorganisms with the ability to degrade petro-polymers under in vitro conditions have been isolated and characterized. In some cases, the enzymes expressed by these microbes have been cloned and sequenced. The rate of polymer biodegradation depends on several factors including chemical structures, molecular weights, and degrees of crystallinity. Polymers are large molecules having both regular crystals (crystalline region) and irregular groups (amorphous region), where the latter provides polymers with flexibility. Highly crystalline polymers like polyethylene (95%), are rigid with a low capacity to resist impacts. PET-based plastics possess a high degree of crystallinity (30–50%), which is one of the principal reasons for their low rate of microbial degradation, which is projected to take more than 50 years for complete degraded in the natural environment, and hundreds of years if discarded into the oceans, due to their lower temperature and oxygen availability. The enzymatic degradation occurs in two stages: adsorption of enzymes on the polymer surface, followed by hydro-peroxidation/hydrolysis of the bonds. The sources of plastic-degrading enzymes can be found in microorganisms from various environments as well as digestive intestine of some invertebrates. Microbial and enzymatic degradation of waste petro-plastics is a promising strategy for depolymerization of waste petro-plastics into polymer monomers for recycling, or to covert waste plastics into higher value bioproducts, such as biodegradable polymers via mineralization. The objective of this review is to outline the advances made in the microbial degradation of synthetic plastics and, overview the enzymes involved in biodegradation.

scholarly journals Comparative Structure-Property Characterization of Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate)s Films under Hydrolytic and Enzymatic Degradation: Finding a Transition Point in 3-Hydroxyvalerate Content

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 728 ◽  
Author(s):  
Vsevolod A. Zhuikov ◽  
Yuliya V. Zhuikova ◽  
Tatiana K. Makhina ◽  
Vera L. Myshkina ◽  
Alexey Rusakov ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Enzymatic Degradation ◽  
Food Packaging ◽  
Hydrolytic Degradation ◽  
Analytical Techniques ◽  
Degree Of Crystallinity ◽  
Structure Property ◽  
Crystallinity Degree ◽  
Average Value

The hydrolytic and enzymatic degradation of polymer films of poly(3-hydroxybutyrate) (PHB) of different molecular mass and its copolymers with 3-hydroxyvalerate (PHBV) of different 3-hydroxyvalerate (3-HV) content and molecular mass, 3-hydroxy-4-methylvalerate (PHB4MV), and polyethylene glycol (PHBV-PEG) produced by the Azotobacter chroococcum 7B by controlled biosynthesis technique were studied under in vitro model conditions. The changes in the physicochemical properties of the polymers during their in vitro degradation in the pancreatic lipase solution and in phosphate-buffered saline for a long time (183 days) were investigated using different analytical techniques. A mathematical model was used to analyze the kinetics of hydrolytic degradation of poly(3-hydroxyaklannoate)s by not autocatalytic and autocatalytic hydrolysis mechanisms. It was also shown that the degree of crystallinity of some polymers changes differently during degradation in vitro. The total mass of the films decreased slightly up to 8–9% (for the high-molecular weight PHBV with the 3-HV content 17.6% and 9%), in contrast to the copolymer molecular mass, the decrease of which reached 80%. The contact angle for all copolymers after the enzymatic degradation decreased by an average value of 23% compared to 17% after the hydrolytic degradation. Young’s modulus increased up to 2-fold. It was shown that the effect of autocatalysis was observed during enzymatic degradation, while autocatalysis was not available during hydrolytic degradation. During hydrolytic and enzymatic degradation in vitro, it was found that PHBV, containing 5.7–5.9 mol.% 3-HV and having about 50% crystallinity degree, presents critical content, beyond which the structural and mechanical properties of the copolymer have essentially changed. The obtained results could be applicable to biomedical polymer systems and food packaging materials.

Papain mediated synthesized gold nanoparticles encore the potency of bioconjugated Flutamide

2020 ◽  
Vol 21 ◽  
Author(s):  
Xiao Xu ◽  
Libo Man
Keyword(s):  
Prostate Cancer ◽  
Gold Nanoparticles ◽  
Cancer Cells ◽  
Drug Loading ◽  
Inhibitory Effect ◽  
Therapeutic Drug ◽  
Ros Generation ◽  
High Concentration ◽  
Vis Spectroscopy

Background: Prostate cancer is the second most common cause of male cancer death after lung cancer in the US. Therefore, there is an urgent need for a highly effective therapeutic drug at substantially low doses. Objective: Anti-androgen drug flutamide was delivered to the prostate cancer cells using papain mediated synthesized gold nanoparticles (PGNPs) as the drug delivery system. PGNPs and flutamide worked synergistically against cancer cells. Method: Flutamide was used to bioconjugate with PGNPs to improve its efficacy against prostate cancer. The synthesis and bioconjugation of flutamide with PGNPs (F-PGNPs) were characterized by various characterization techniques such as UV–vis spectroscopy, Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), and zeta potential to ensure the synthesis, size, shape, size distribution, and stability. The drug loading efficiency of flutamide in F-PGNPs was confirmed and validated by UV–vis spectroscopy. Eventually, in vitro studies were performed to determine the potency of F-PGNPs, changes in nuclear morphology, and generation of Reactive Oxygen Species (ROS). Results: The efficacy of F-PGNPs (IC50 is 46.54 µg/mL) was found to be improved significantly over pure flutamide (IC50 is 64.63 µg/mL) against human prostate cancer PC–3 cell line whereas F-PGNPs did not show any significant toxicity up to a fairly high concentration toward normal mouse macrophage J774A.1 cells. The apoptotic effects and ROS generation of F-PGNPs were analyzed by increased permeability of the cell membrane and condensed chromatin with deep blue and green fluorescent nucleus, respectively. The results clearly showed that F-PGNPs significantly improved the potency of flutamide by delivering it directly into the nucleus of cancer cells through caveolae-dependent endocytosis. Conclusion: Thus, the greater inhibitory effect of F-PGNPs over the pure drug would be of great advantage during prostate cancer treatment.

Preparation and in vitro Evaluation of Bioadhesive Microparticulate System

1970 ◽  
Vol 1 (3) ◽  
pp. 257-266
Author(s):  
Nagda C. D. ◽  
Chotai N. P. ◽  
Patel S. B. ◽  
Soni T. J ◽  
Patel U. L
Keyword(s):  
Drug Loading ◽  
In Vitro Release ◽  
Phenyl Acetic Acid ◽  
Solvent Evaporation Method ◽  
Elimination Half ◽  
Release Studies ◽  
Differential Scanning Colorimetry ◽  
Polymer Interactions ◽  
Vitro Release

Aceclofenac (ACE) is NSAIDs of a phenyl acetic acid class. It is indicated in arthritis and osteoarthritis, rheumatoid arthritis, ankylosing spondylitis. It has short elimination half life of 4 hours. The objective of the study is to design, characterize and evaluate bioadhesive microspheres of ACE employing carbopol (CP) as bioadhesive polymer. Bioadhesive microspheres of ACE were prepared by solvent evaporation method. The prepared microspheres were free flowing and spherical in shape and characterized for drug loading, mucoadhesion test, infrared spectroscopy (IR), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The in-vitro release studies were performed using pH 6.8 phosphate buffer. The drug loaded microspheres in a ratio of 1:5 showed 47% of drug entrapment; percentage mucoadhesion was 81% and 89% release in 10 h. The infrared spectra and DSC showed stable character of aceclofenac in the drug loaded microspheres and revealed the absence of drug-polymer interactions. SEM studies showed that the microspheres are spherical and porous in nature. The in vitro release profiles from microspheres of different polymer-drug ratios followed Higuchi model.

Solid Lipid Nanoparticles for Topical Delivery of Acitretin for the Treatment of Psoriasis by Design of Experiment

2020 ◽  
Vol 12 (2) ◽  
pp. 4474-4491
Author(s):  
Rajkumar Aland ◽  
Ganesan M ◽  
P. Rajeswara Rao ◽  
Bhikshapathi D. V. R. N.
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Solid Lipid Nanoparticles ◽  
Drug Loading ◽  
Entrapment Efficiency ◽  
Lipid Nanoparticles ◽  
Tem Analysis ◽  
In Vitro Drug Release ◽  
Solid Lipid

The main objective for this investigation is to develop and optimize the solid lipid nanoparticles formulation of acitretin for the effective drug delivery. Acitretin loaded SLNs were prepared by hot homogenization followed by the ultrasonication using Taguchi’s orthogonal array with eight parameters that could affect the particle size and entrapment efficiency. Based on the results from the analyses of the responses obtained from Taguchi design, three different independent variables including surfactant concentration (%), lipid to drug ratio (w/w) and sonication time (s) were selected for further investigation using central composite design. The  lipid Dynasan-116, surfactant poloxomer-188 and co surfactant egg lecithin resulted in better percent drug loading and evaluated for particle size, zeta potential, drug entrapment efficiency, in vitro drug release and stability. All parameters were found to be in an acceptable range. TEM analysis has demonstrated the presence of individual nanoparticles in spherical shape and the results were compatible with particle size measurements.  In vitro drug release of optimized SLN formulation (F2) was found to be 95.63 ± 1.52%, whereas pure drug release was 30.12 after 60 min and the major mechanism of drug release follows first order kinetics release data for optimized formulation (F2) with non-Fickian (anomalous) with a strong correlation coefficient (R2 = 0.94572) of Korsemeyer-Peppas model. The total drug content of acitretin gel formulation was found to 99.86 ± 0.012% and the diameter of gel formulation was 6.9 ± 0.021 cm and that of marketed gel was found to be 5.7 ± 0.06 cm, indicating better spreadability of SLN based gel formulation. The viscosity of gel formulation at 5 rpm was found to be 6.1 x 103 ± 0.4 x 103 cp. The release rate (flux) of acitretin across the membrane and excised skin differs significantly, which indicates about the barrier properties of skin. The flux value for SLN based gel formulation (182.754 ± 3.126 μg cm−2 h−1) was found to be higher than that for marketed gel (122.345 ± 4.786 μg cm−2 h−1). The higher flux and Kp values of SLN based gel suggest that it might be able to enter the skin easily as compared with marketed gel with an advantage of low interfacial tension of the emulsifier film that ensures an excellent contact to the skin. This topically oriented SLN based gel formulation could be useful in providing site-specific dermal treatment of psoriasis

New Platinum (II) Ternary Complexes of Formamidine and Pyrophosphate: Synthesis, Characterization and DFT Calculations and In vitro Cytotoxicity

2020 ◽  
Vol 23 (7) ◽  
pp. 611-623
Author(s):  
Ahmed A. Soliman ◽  
Fawzy A. Attaby ◽  
Othman I. Alajrawy ◽  
Azza A.A. Abou-hussein ◽  
Wolfgang Linert
Keyword(s):  
Cell Line ◽  
Cancer Cell ◽  
Theoretical Calculations ◽  
Thermal Analyses ◽  
Cancer Cell Line ◽  
Cellular Growth ◽  
Planar Geometry ◽  
Square Planar ◽  
Vis Spectroscopy

Aim and Objective: Platinum (II) and platinum (IV) of pyrophosphate complexes have been prepared and characterized to discover their potential as antitumor drugs. This study was conducted to prepare and characterize new ternary platinum (II) complexes with formamidine and pyrophosphate as an antitumor candidate. Materials and Methods: The complexes have been characterized by mass, infrared, UV-Vis. spectroscopy, elemental analysis, magnetic susceptibility, thermal analyses, and theoretical calculations. They have been tested for their cytotoxicity, which was carried out using the fastcolorimetric assay for cellular growth and survival against MCF-7 (breast cancer cell line), HCT- 116 (colon carcinoma cell line), and HepG-2 (hepatocellular cancer cell line). Results: All complexes are diamagnetic, and the electronic spectral data displayed the bands due to square planar Pt(II) complexes. The optimized complexes structures (1-4) indicated a distorted square planar geometry where O-Pt-O and N-Pt-N bond angles were 82.04°-96.44°, respectively. Conclusion: The complexes showed noticeable cytotoxicity and are considered as promising antitumor candidates for further applications.

Sign in / Sign up

Export Citation Format

Share Document