scholarly journals Plasmonic photothermal release of docetaxel by gold nanoparticles incorporated onto halloysite nanotubes with conjugated 2D8-E3 antibodies for selective cancer therapy

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Reza Taheri-Ledari ◽  
Wenjie Zhang ◽  
Maral Radmanesh ◽  
Nicole Cathcart ◽  
Ali Maleki ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Hydrogen Bonding ◽  
Controlled Release ◽  
Halloysite Nanotubes ◽  
The Body ◽  
Biologically Active ◽  
Strong Hydrogen Bond ◽  
Photothermal Effect ◽  
Scanning Calorimetry

Abstract Background Applied nanomaterials in targeted drug delivery have received increased attention due to tangible advantages, including enhanced cell adhesion and internalization, controlled targeted release, convenient detection in the body, enhanced biodegradation, etc. Furthermore, conjugation of the biologically active ingredients with the drug-containing nanocarriers (nanobioconjugates) has realized impressive opportunities in targeted therapy. Among diverse nanostructures, halloysite nanotubes (NHTs) with a rolled multilayer structure offer great possibilities for drug encapsulation and controlled release. The presence of a strong hydrogen bond network between the rolled HNT layers enables the controlled release of the encapsulated drug molecules through the modulation of hydrogen bonding either in acidic conditions or at higher temperatures. The latter can be conveniently achieved through the photothermal effect via the incorporation of plasmonic nanoparticles. Results The developed nanotherapeutic integrated natural halloysite nanotubes (HNTs) as a carrier; gold nanoparticles (AuNPs) for selective release; docetaxel (DTX) as a cytotoxic anticancer agent; human IgG1 sortilin 2D8-E3 monoclonal antibody (SORT) for selective targeting; and 3-chloropropyltrimethoxysilane as a linker for antibody attachment that also enhances the hydrophobicity of DTX@HNT/Au-SORT and minimizes DTX leaching in body’s internal environment. HNTs efficiently store DTX at room temperature and release it at higher temperatures via disruption of interlayer hydrogen bonding. The role of the physical expansion and disruption of the interlayer hydrogen bonding in HNTs for the controlled DTX release has been studied by dynamic light scattering (DLS), electron microscopy (EM), and differential scanning calorimetry (DSC) at different pH conditions. HNT interlayer bond disruption has been confirmed to take place at a much lower temperature (44 °C) at low pH vs. 88 °C, at neutral pH thus enabling the effective drug release by DTX@HNT/Au-SORT through plasmonic photothermal therapy (PPTT) by light interaction with localized plasmon resonance (LSPR) of AuNPs incorporated into the HNT pores. Conclusions Selective ovarian tumor targeting was accomplished, demonstrating practical efficiency of the designed nanocomposite therapeutic, DTX@HNT/Au-SORT. The antitumor activity of DTX@HNT/Au-SORT (apoptosis of 90 ± 0.3%) was confirmed by in vitro experiments using a caov-4 (ATCC HTB76) cell line (sortilin expression > 70%) that was successfully targeted by the sortilin 2D8-E3 mAb, tagged on the DTX@HNT/Au. Graphic abstract

scholarly journals Thiol-Responsive Gold Nanodot Swarm with Glycol Chitosan for Photothermal Cancer Therapy

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5980
Author(s):  
SeongHoon Jo ◽  
In-Cheol Sun ◽  
Wan Su Yun ◽  
Jinseong Kim ◽  
Dong-Kwon Lim ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Cell Death ◽  
Near Infrared ◽  
The Body ◽  
Photothermal Effect ◽  
Immunogenic Cell Death ◽  
Particle Structure ◽  
Glycol Chitosan ◽  
Nir Light

Photothermal therapy (PTT) is one of the most promising cancer treatment methods because hyperthermal effects and immunogenic cell death via PTT are destructive to cancer. However, PTT requires photoabsorbers that absorb near-infrared (NIR) light with deeper penetration depth in the body and effectively convert light into heat. Gold nanoparticles have various unique properties which are suitable for photoabsorbers, e.g., controllable optical properties and easy surface modification. We developed gold nanodot swarms (AuNSw) by creating small gold nanoparticles (sGNPs) in the presence of hydrophobically-modified glycol chitosan. The sGNPs assembled with each other through their interaction with amine groups of glycol chitosan. AuNSw absorbed 808-nm laser and increased temperature to 55 °C. In contrast, AuNSw lost its particle structure upon exposure to thiolated molecules and did not convert NIR light into heat. In vitro studies demonstrated the photothermal effect and immunogenic cell death after PTT with AuNSW. After intratumoral injection of AuNSw with laser irradiation, tumor growth of xenograft mouse models was depressed. We found hyperthermal damage and immunogenic cell death in tumor tissues through histological and biochemical analyses. Thiol-responsive AuNSw showed feasibility for PTT, with advanced functionality in the tumor microenvironment.

scholarly journals Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Chukwuebuka H. Ozoude ◽  
Chukwuemeka P. Azubuike ◽  
Modupe O. Ologunagba ◽  
Sejoro S. Tonuewa ◽  
Cecilia I. Igwilo
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Metformin Hydrochloride ◽  
Scanning Calorimetry ◽  
Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

scholarly journals Fabrication and In Vitro Evaluation of pH-Sensitive Polymeric Hydrogels as Controlled Release Carriers

Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 110
Author(s):  
Muhammad Suhail ◽  
Chih-Wun Fang ◽  
Arshad Khan ◽  
Muhammad Usman Minhas ◽  
Pao-Chu Wu
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Acrylic Acid ◽  
Chondroitin Sulfate ◽  
Diclofenac Sodium ◽  
Research Work ◽  
Controlled Delivery ◽  
Scanning Calorimetry ◽  
Release Studies

The purpose of the current investigation was to develop chondroitin sulfate/carbopol-co-poly(acrylic acid) (CS/CBP-co-PAA) hydrogels for controlled delivery of diclofenac sodium (DS). Different concentrations of polymers chondroitin sulfate (CS), carbopol 934 (CBP), and monomer acrylic acid (AA) were cross-linked by ethylene glycol dimethylacrylate (EGDMA) in the presence of ammonium peroxodisulfate (APS) (initiator). The fabricated hydrogels were characterized for further experiments. Characterizations such as Scanning electron microscopy (SEM), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Powder X-ray diffractometry (PXRD), and Fourier transform infrared spectroscopy (FTIR) were conducted to understand the surface morphology, thermodynamic stability, crystallinity of the drug, ingredients, and developed hydrogels. The swelling and drug release studies were conducted at two different pH mediums (pH 1.2 and 7.4), and pH-dependent swelling and drug release was shown due to the presence of functional groups of both polymers and monomers; hence, greater swelling and drug release was observed at the higher pH (pH 7.4). The percent drug release of the developed system and commercially available product cataflam was compared and high controlled release of the drug from the developed system was observed at both low and high pH. The mechanism of drug release from the hydrogels followed Korsmeyer–Peppas model. Conclusively, the current research work demonstrated that the prepared hydrogel could be considered as a suitable candidate for controlled delivery of diclofenac sodium.

DESIGN AND EVALUATION OF EUDRAGIT COATED LOSARTAN POTASSIUM CONTROLLED RELEASE PELLETS BY PAN COATING TECHNIQUE

INDIAN DRUGS ◽  
2013 ◽  
Vol 50 (10) ◽  
pp. 30-38
Author(s):  
S Vidyadhara ◽  
◽  
R. L. C. Sasidhar ◽  
P Thrilochani ◽  
L. K. Lavanya
Keyword(s):  
Controlled Release ◽  
Drug Release ◽  
Methyl Cellulose ◽  
Losartan Potassium ◽  
Scanning Calorimetry ◽  
Coating Agent ◽  
Coating Technique ◽  
S 100 ◽  
Eudragit S 100

The present investigation was focused on the development and evaluation of controlled release pellets of losartan potassium with Eudragit S 100 and hydroxypropyl methyl cellulose phthalate (HPMCP) by employing pan coating technique. Eudragit S 100, a high viscosity grade controlled release polymer, was mainly used as coating agent for regulating the drug release from pellets. HPMCP, an enteric coating polymer was used in the present study to regulate the drug release at varied G.I. pH conditions. The prepared pellets were evaluated for particle size, drug content, friability and for in vitro drug release. The formulations were further characterized to identify any possible interactions by FTIR spectroscopy and differential scanning calorimetry. The surface morphology of the pellets was studied by scanning electron microscopy. From the results it was observed that due to increase in the concentration of Eudragit the drug release was extended up to 12 hours. The increase in the HPMCP polymeric concentration in formulations showed initial delay in drug release.

The Permeability of Dialytic Membranes to Endotoxins: Clinical and Experimental Findings

1989 ◽  
Vol 12 (8) ◽  
pp. 505-508 ◽  
Author(s):  
G. Passavanti ◽  
E. Buongiorno ◽  
G. De Fino ◽  
D. Fumarola ◽  
P. Coratelli
Keyword(s):  
Active Component ◽  
Lipid A ◽  
In Vitro Study ◽  
The Body ◽  
Biologically Active ◽  
Limulus Amebocyte Lysate ◽  
Membrane Interaction ◽  
Experimental Findings

This study of 20 endotoxemic patients submitted to 70 hemodialyses (HD) found a reduction of the pre-HD limulus amebocyte lysate (LAL) positivity in 50 HD (71%), without appreciable differences in terms of effectiveness between cuprophan and AN 69 membranes. To define the mechanisms responsible for the reduction in LAL positivity during HD, the membranes were used in two in vitro studies, the first of which showed that the LAL positivity of blood containing lipopolysaccharide (LPS), submitted to hemofiltration (HF) for 300 min, remained unchanged and the ultrafiltrate remained constantly LAL negative. These results suggest that the reduction in LAL positivity observed in HD in vivo, an expression of reduced endotoxemia, cannot be attributed either to the filtration of the LPS as such or to its fragmentation following blood-membrane interaction into theoretically less filtrable molecules or to mechanisms of LPS adsorption on the membrane. The in vivo reduction of LAL positivity is more likely due to removal of the filtrable endotoxin fragments already released in the body, like lipid A, the biologically active component of LPS, known to react to LAL. This hypothesis was borne out by the second in vitro study, where the LAL positivity of blood containing lipid A, treated by HF for 80 min, gradually decreased, and dialytic permeability to lipid A was confirmed by the appearance of LAL positivity in the ultrafiltrate.

The preparation, characterization, structure and dissolution analysis of apremilast solvatomorphs

2017 ◽  
Vol 73 (4) ◽  
pp. 305-313 ◽  
Author(s):  
Yun-Deng Wu ◽  
Xiao-Lei Zhang ◽  
Xiao-Hong Liu ◽  
Jian Xu ◽  
Mei Zhang ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Hydrogen Bonding ◽  
Psoriatic Arthritis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Dissolution Rates ◽  
X Ray ◽  
Similarity Factor ◽  
Hydrogen Bonding Interactions

Apremilast (AP) {systematic name: (S)-2-[1-(3-ethoxy-4-methoxyphenyl)-2-(methylsulfonyl)ethyl]-4-acetamidoisoindoline-1,3-dione} is an inhibitor of phosphodieasterase-4 (PDE4) and is indicated for the treatment of adult patients with active psoriatic arthritis. The ability of AP to form solvates has been investigated and three solvatomorphs of AP, namely, the AP ethyl acetate hemisolvate, C22H24N2O7S·0.5C4H8O2, the AP toluene hemisolvate, C22H24N2O7S·0.5C7H8, and the AP dichloromethane monosolvate, C22H24N2O7S·CH2Cl2, were obtained. The three AP solvatomorphs were characterized by X-ray powder diffraction, thermogravimetric analysis and differential scanning calorimetry. Single-crystal X-ray diffraction was used to analyze the structures, crystal symmetry, packing modes, stoichiometry and hydrogen-bonding interactions of the solvatomorphs. In addition, dissolution analyses were performed to study the dissolution rates of different AP solvatomorph tablets in vitro and to make comparisons with commercial apremilast tablets (produced by Celgene); all three solvatomorphs showed similar dissolution rates and similar values of the similarity factor f2 in a comparison of their dissolution profiles.

scholarly journals A Cyclodextrin-Based Controlled Release System in the Simulation of In Vitro Small Intestine

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1212
Author(s):  
Danni Zheng ◽  
Liuxi Xia ◽  
Hangyan Ji ◽  
Zhengyu Jin ◽  
Yuxiang Bai
Keyword(s):  
Complex System ◽  
Small Intestine ◽  
Controlled Release ◽  
Glucose Production ◽  
Scanning Calorimetry ◽  
Release System ◽  
In Vitro Simulation ◽  
Controlled Release System ◽  
Enteric Coated

A novel cyclodextrin (CD)-based controlled release system was developed in the small intestine to control the rate of drug release, on the premise of enteric-coated tablets. The system was designed based on the enzymes exogenous β-cyclodextrin glycosyltransferase (β-CGTase) and endogenous maltase-glucoamylase (MG), wherein MG is secreted in the small intestine and substituted by a congenerous amyloglucosidase (AG). The vanillin-/curcumin-β-CD complexes were prepared and detected by Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC), and host CD degradation was measured based on the glucose yield. The combination of β-CGTase and AG was also functional in the CD complex system. The variations in the concentrations of added β-CGTase, with AG constantly in excess, could effectively alter the rate of host CD degradation and guest release by monitoring glucose production and color disappearance, thus, demonstrating that guest release in the CD complex system could be precisely controlled by changing the amount of β-CGTase used. Thus, the in vitro simulation of the system indicated that a novel controlled release system, based on endogenous MG, could be established in the small intestine. The CD-based controlled release system can be potentially applied in drug delivery and absorption in the small intestine.

Effect of the sulfur-containing compounds on the quinoid process of adrenaline autoxidation; potential neuroprotectors

2019 ◽  
Vol 65 (4) ◽  
pp. 316-323
Author(s):  
T.V. Sirota
Keyword(s):  
Antioxidant Properties ◽  
Enzymatic Reaction ◽  
The Body ◽  
Biologically Active ◽  
Treatment And Prevention ◽  
Multistep Process ◽  
Ic50 Values ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

The superoxide-generating reaction of adrenaline autoxidation in an alkaline medium, used in vitro to identify the antioxidant properties of various compounds, simulates the complex multistep process of quinoid oxidation of catecholamines (CA) in the body. Sulfur-containing cysteine (Cys) and reduced glutathione (GSH), as well as oxidized glutathione (GSSG), have been shown to inhibit this process. The studied substances were considered as inhibitors of quinoid oxidation and are evaluated as antioxidants. The IC50 values for Cys and GSH were close to 7.5 mM. Inhibition by GSSG was weaker; represented approximately 50-70% of Cys and GSH. Other sulfur-containing compounds that differ in chemical structure, the amino acids taurine and methionine were ineffective. The interest in this model and the search for effective compounds acting on this reaction is associated with one of the mechanisms of the etiopathogenesis of Parkinson's disease (PD) discussed in the literature, which occurs when the biochemical transformations of dopamine CA and its quinoid oxidation process are violated. Cys, GSH and GSSG in the model system inhibit quinoid oxidation of adrenaline, as a result of which the formation of superoxide (O2 ·-) is also inhibited. Experiments with the superoxide-generating enzymatic reaction xanthine xanthioxidase, the chemistry of which is different and not related to formation of quinoid metabolites, showed that the studied substances did not inhibit O2 ·- formation in this model. Thus, it was established that the biologically active sulfur-containing compounds Cys, GSH and GSSG are specific inhibitors of quinoid oxidation of CA, and are likely to be able to play the role of a neuroprotector. It is proposed to use these compounds in the treatment and prevention of PD by activating their biosynthesis in the body.

Preparation and in vitro evaluation of doxorubicin loaded alendronate modified hollow gold nanoparticles for bone-targeted chemo-photothermal therapy

2020 ◽  
Vol 10 (11) ◽  
pp. 1950-1959
Author(s):  
Lei Yang ◽  
Yumin Hu ◽  
Yuanfen Liu ◽  
Yanyan Liu ◽  
Si Miao ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Laser Irradiation ◽  
Photothermal Therapy ◽  
Bone Tumors ◽  
Drug Loading ◽  
Photothermal Effect ◽  
Osteosarcoma Cells ◽  
Hollow Gold Nanoparticles ◽  
Human Osteosarcoma Cells

The treatment of malignant bone tumors (including primary bone tumors and metastatic bone tumors) has always been a clinical challenge. The purpose of this study is to design a bone-targeted nano-carrier with photothermal effect to achieve chemo-photothermal therapy (CPT), which allows the minimal use of photothermal agents and chemical drugs to target bone tumors. Alendronate modified hollow gold nanoparticles (HGNPs- ALN) were synthesized using mercapto polyethylene glycol carboxyl (SH-PEG2000-COOH) as the connecting arm, fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) data show that HGNPs-ALN with a particle size of about 80 nm has been successfully synthesized. The hydroxyapatite affinity experiment in vitro indicated that HGNPs-ALN exhibited a high affinity to bone. In addition, the temperature of HGNPs-ALN under near-infrared laser irradiation can rise to 53 °C, which can achieve effective photothermal therapy for bone tumors. Bone-targeted hollow gold nanoparticles (DOX@HGNPs-ALN) loaded with doxorubicin hydrochloride (DOX) were synthesized by one-pot method. By comparing the stability and drug loading of HGNPs-ALN, it was concluded that the optimal mass ratio of HGNPs-ALN (calculated by the amount of gold) to DOX was about 1:2. HGNPs-ALN and DOX@HGNPs-ALN both have good photothermal stability and photothermal transformation properties, and confirmed the safety of HGNPs on human osteosarcoma cells. MTT experiments showed that DOX@HGNPs-ALN had the strongest killing effect on MG-63 osteosarcoma cells under laser irradiation (the killing rate is about 65%). According to these results, it can be considered that DOX@HGNPs-ALN has the potential of CPT synergistic targeting therapy for bone tumors.

Synthesis and Kinetic Studies on Controlled Release of 6-Thioguanine Entrapped Polyethylene Glycol-Co-Polylactic Acid Polymer Nanoparticles

2011 ◽  
Vol 9 (1) ◽  
Author(s):  
Sathishkumar Kannaiyan ◽  
T.G.Ashwin Narayanan ◽  
P.Karthick Sarathy ◽  
Nagarjun Sudhakar ◽  
Rama Krishnan
Keyword(s):  
Gold Nanoparticles ◽  
Lactic Acid ◽  
Polyethylene Glycol ◽  
Controlled Release ◽  
Drug Release ◽  
Kinetic Equations ◽  
Kinetic Studies ◽  
Poly Lactic Acid ◽  
Average Size

Poly lactic acid-polyethylene glycol (PLA-co-PEG) copolyester was synthesized from oligomer of L-lactic acid and poly ethylene glycol (PEG) using stannous octoate as catalyst. 6-Thioguanine containing Poly lactic acid-polyethylene glycol (PLA-co-PEG) nanocapsules were prepared in the presence and absence of gold nanoparticles via the W/O/W emulsification solvent-evaporation method. The morphologies of prepared nanocapsules changed substantially because of the presence of gold nanoparticles. From SEM and TEM measurements, the average size of the polymer nanocapsules and gold nanoparticles were found to be in range of 230-260 nm and 18-20 nm, respectively. In general the drug release was quicker in Phosphate buffer saline (pH 7.4) compared to 0.1M hydrochloric acid and this may be due to higher solubility, higher swelling and penetration properties of PLA-co-PEG in PBS compared to HCl. Polymer nanocapsules with gold show a prolonged controlled release with higher encapsulation efficiency (75%) compared to that of polymer nanocapsules (45%) in the absence of gold nanoparticles. It may be due to the more entrapping efficiency of gold and less diffusivity of drugs from the nanocapsules. Application of in vitro drug release data to various kinetic equations indicated Higuchi model, indicating a uniform distribution of thioguanine in the nanocapsules.

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