Keywords : Drug delivery


SPIONs and curcumin co-encapsulated mixed micelles based nanoformulation for biomedical applications

Ganeshlenin Kandasamy; Atul Sudame; Dipak Maity

Advanced Materials Letters, 2019, Volume 10, Issue 3, Pages 185-188
DOI: 10.5185/amlett.2019.2169

In this work, we have synthesized oleylamine (OM)-coated hydrophobic monodispersed SPIONs with an average particle size of ~9 nm via thermal decomposition method. The as-prepared hydrophobic SPIONs are co-encapsulated along with a drug (curcumin, Cur) within the mixed micelles based nanoformulations which is made of d-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and Pluronic F127 while keeping the TPGS:F127 ratios at 100:0, 75:25, 50:50, 25:75 and 0:100. Then, the nanoformulations are characterized for hydrodynamic size via dynamic light scattering (DLS) technique, and drug/SPIONs encapsulation efficiencies are determined via UV-vis spectroscopy. Among all the nanoformulation, the mixed micelle with 50:50 TPGS:F127 has exhibited relatively lower hydrodynamic diameter (Dh) (~ 84 nm), better encapsulation efficiencies of Cur and SPIONs (~95% / 56%), and high yield (above 90%). Moreover, morphology and encapsulation of SPIONs/Cur inside the optimized 50:50 TPGS:F127 nanoformulation is confirmed by TEM. In addition, only 10% of Cur is released during 12h time period from optimized nanoformulation indicating the sustained-release property, whereas ~68% of Cur is quickly released in free Cur experiments for the same time period. Hence, the SPIONs/Cur are efficiently co-encapsulated inside the TPGS:F127 mixed micelle based nanoformulation which could be used for further biomedical applications.

Nanoengineered plasma polymer films for biomedical applications

Krasimir Vasilev; Melanie Ramiasa-MacGregor

Advanced Materials Letters, 2018, Volume 9, Issue 1, Pages 42-52
DOI: 10.5185/amlett.2018.1691

This forward looking concise review describes recent advances in the field of nanoengineered plasma polymer films. These types of coatings are relevant in many fields of application and have gained substantial research and technological interest over the last decade. The review starts with an introduction of plasma polymerization as a technique for preparation for nanometer thin polymer-like coatings. This is followed by the examples of the use of nanoengineered plasma polymer coatings in applications relevant to biomedical devices. Applications in antibacterial coatings and drug delivery vehicles are discussed. Significant section of this paper is dedicated to cell guidance surfaces which have an extensive range of applications ranging from coatings for medical devices to research tools that can help unraveling complex biological questions and vehicles for the growing field of cell therapies. The vision of the authors about the future directions of the field have also been presented, including a section on novel oxazoline based coatings that carry great promise for advances in the biomaterial and biomedical fields.

Increasing the metal loading in passion fruit-like nano-architectures

Rosa D

Advanced Materials Letters, 2017, Volume 8, Issue 12, Pages 1156-1160
DOI: 10.5185/amlett.2017.1668

Noble metal nanostructures have demonstrated many intriguing features for both therapy and diagnosis in a number of diseases. However, their clinical translation is prevented by their accumulation in organisms that can result in toxicity and interference with common medical diagnoses. In order to combine the most interesting behaviour of metal nanoparticles with the possibility of their body clearance, we have recently introduced and tested the passion fruit-like nano-architectures. They are versatile 100 nm biodegradable nanostructures composed by a silica shell embedding functional polymeric arrays of ultra-small noble metal nanoparticles. Here, we report a novel simple and robust protocol to increase the loading of ultra small gold nanoparticles in the nano-architectures, promoting their possible application in clinical diagnosis. 

Drug Delivery & Tissue Engineering Conference

Ashutosh Tiwari

Advanced Materials Letters, 2017, Volume 8, Issue 9, Pages 883-883
DOI: 10.5185/amlett.2017/9001

International Association of Advanced Materials (IAAM, www.iaamonline.org) is pleased to announce Drug Delivery & Tissue Engineering Conference 2018, Singapore with collaboration of VBRI Press AB, Sweden (www.vbripress.com). The conference is dedicated on the technology and systems in the drug delivery, different routes and methods of administration, nanomedicine, peptide, gene and protein delivery, pharmaceutical devices and their developments, and major challenges in drug delivery research and markets.

Mixed lipid/polymer nanostructures: From advanced materials to drug delivery systems

Natassa Pippa; Athanasios Skandalis; Costas Demetzos; Marcin Libera; Andrzej Marcinkowski; Barbara Trzebicka

Advanced Materials Letters, 2017, Volume 8, Issue 4, Pages 428-434
DOI: 10.5185/amlett.2017.1414

The aim of this investigation was to study the alterations of the physicochemical characteristics of L-α-phosphatidylcholine, hydrogenated (Soy) (HSPC) and dipalmitoyl phosphatidyl choline (DPPC) liposomes, caused by the incorporation of a poly (oligoethylene glycol acrylate)-b-poly(lauryl acrylate) (POEGA-PLA) block copolymer at different molar ratios. We used Dynamic and Electrophoretic Light Scattering to determine the size and the ζ-potential; imaging techniques for investigate the structure and Static Light Scattering for quantifying the fractal morphology of the prepared nanosystems in situ. The size of mixed nanostructures became smaller with the incorporation of the block copolymer into the lipid membrane.  The size of the prepared nanosystems ranged between 50-80nm. The fractal dimension (df) decreased significantly with the incorporation of block copolymer into liposomal bilayers. The morphology of DPPC:POEGA-PLA mixed nanostructures (with df equal to 1.8) is open (more loose). On the other hand, the morphology of HSPC: POEGA-PLA (with df equal to 2.1) is more compact and dense. The molar ratio of the POEGA-PLA did not alter the morphology of the mixed nanostructures, expect from HSPC:POEGA-PLA system. Finally, we studied the drug loading properties of the mixed nanostructures in order to examine their properties as advanced Drug Delivery nanosystems. 

Flexible cefalexin-immobilized graphene oxide film for antibacterial and drug delivery

Xun Xu; Fangwang Ming; Jinqing Hong; Zhoucheng Wang

Advanced Materials Letters, 2017, Volume 8, Issue 3, Pages 309-314
DOI: 10.5185/amlett.2017.7103

The flexible and freestanding graphene oxide (GO) film was fabricated for drug delivery and antibacterial. The film was synthesized by covalently attaching cefalexin onto graphene oxide sheets and then made by filtration of the colloidal suspension. SEM and optical images show that the Cefalexin-grafted graphene oxide (GO-CE) film possesses the unique 2D layer-by-layer structure and it could form channels for drug release when immersed in water. The drug loading and release tests certify that the GO-CE film is a promising drug delivery membrane with high load capacity (0.621 mg mg -1 ) and long-acting release properties (72 h), and can effectively inhibit the growth of E. coli and S. aureus bacteria while showing minimal cytotoxicity for a long time. The cellular culture results of the HeLa Cells indicate that the GO-CE film exhibits excellent biocompatibility. Based on these advantages, the GO-CE film is expected to be used in the environmental and medical applications.

Tumor-targeting Hederagenin-loaded Magnetic Nanoparticles For Anti-cancer Drug Delivery

Kwon-Jai Lee; Jeung Hee An; Jae-Soo Shin; Dong-Hee Kim; Kang-Hyun Chung

Advanced Materials Letters, 2016, Volume 7, Issue 5, Pages 366-370
DOI: 10.5185/amlett.2016.6134

In this study, the anti-tumor activity of hederagenin-loaded magnetic nanoparticles (HMP) was examined in cancer cells. Composite nanoparticles with an average size of 32.5 nm were prepared using a chemical co-precipitation technique. The characteristics of the particles were determined via X-ray diffraction, field emission scanning electron microscopy, attenuated total reflectance fourier transform-infrared spectroscopy, and energy-dispersive X-ray spectroscopy. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the magnetic nanoparticles were non-toxic against cancer. In particular, HMPs were cytotoxic at 73.12 % breast cancer (MCF-7), at 70.2 % against prostate cancer (DU145 cells), at  72.15 % against neuroblastoma cancer cells (U87), at 579.15 % in human brain cancer cells (SH-SY5Y), and at 74.5 % in human cervical cancer cells (HeLa) at 250 mg/mL. Our results demonstrated the biological applicability of HMPs as anticancer agents and as agents for enhanced drug delivery against human prostate cancer cells. Our results indicate that the magnetic nanoparticles were biostable and that HMPs functioned effectively as drug delivery vehicles. 

A Facile Strategy To Elute Amoxicillin In A Controlled Way From Hydroxyapatite-gelatin Composite

K. Sangeetha; Y. Yokogawa; E.K. Girija

Advanced Materials Letters, 2015, Volume 6, Issue 12, Pages 1031-1036
DOI: 10.5185/amlett.2015.5905

In recent decades bone infection is one of the most challenging issues encountered in biomedical field and local antibiotic delivery is a key strategy to overcome this issue. Hence developing bioactive materials in combination with antibiotics is much focused recently for bone substitutes. Here we report the fabrication of pristine and natural polymer (gelatin) composite matrices of hydroxyapatite (HA) by a facile wet precipitation method and their drug release behavior from directly loaded and in situ loaded matrices using amoxicillin as the model drug. The products thus obtained were analyzed by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetry (TG) and scanning electron microscopy (SEM) which confirmed the formation of HA and nanocomposite of HA with gelatin. It was observed that under physiological conditions, for sustained and prolonged release of the drug in situ loading in composite matrix is a favorable approach.

Green Synthesis Of Gold Nanoparticles For controlled Delivery

S. Malathi; M. D. Balakumaran; P. T. Kalaichelvan; S. Balasubramanian

Advanced Materials Letters, 2013, Volume 4, Issue 12, Pages 933-940
DOI: 10.5185/amlett.2013.5477

Gold nanoparticles (AuNPs) have been synthesized by green method using chitosan as a reducing/capping agent. We designed a biocompatible carrier for controlled release of hydrophobic drugs. The designed carrier was prepared by using single oil-in-water (O/W) emulsion. The resulting AuNPs were characterized by UV–Vis spectroscopy (UV–Vis) and Fourier transform infrared spectroscopy (FTIR). The transmission electron microscopy (TEM) studies indicate the spherical nature of drug loaded nanoparticles with the size of 50nm while the average particle size of AuNPs is found to be 2-3nm. The chitosan capped AuNPs showed a surface plasmon resonance at 526nm. The FTIR spectra suggest that the amine group is mainly responsible for the reduction of tetrachloroauric acid and capping the AuNPs. The controlled release of rifampicin (RIF) was investigated by in vitro studies using phosphate buffer saline (PBS) at pH=7.4. The loading efficiency of drug molecule was found to be 71%. The encapsulated drugs were released at 37 °C temperature. The results have been fit into various mechanistic models and it is found that the Higuchi model fits in to the release behavior of RIF. Further, the antibacterial activity of RIF loaded nanoparticles was examined by Gram +ve (bacillus subtils) and Gram -ve (Pseudomonas aeruginosa) bacteria. The application of similar drug loaded nanocarrier for treating other diseases like cancer can also be investigated.

Preparation And Characterization Of Cellulose Derived From Rice Husk For Drug Delivery

S. K. Shukla; G. C. Dubey;Ashutosh Tiwari; Anand Bharadvaja

Advanced Materials Letters, 2013, Volume 4, Issue 9, Pages 714-719
DOI: 10.5185/amlett.2013.2415

Cellulose has been the extracted from rice husk by chemical treatment with aqueous solution of sodium hydroxide. The physical properties of derived cellulose (water uptake and swelling behavior) has been investigated with view of different applications. The morphology and chemical structure were investigated by Infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Thermogravimetry (TG) techniques. The results revealed the formation of homogeneous porous (micro size) membrane. Further, the UV-vis spectra of cellulose in different pH shows its responsiveness towards hydronium ion, which is suitable for drug delivery. Further, obtained cellulose was used for drug delivery under optimized pH.

Preparation and characterization of novel spin labeled magnetic nanoparticles

Hongli Zhao; Zhigang Zhang; Zijun Zhao; Ronghua Yu; Yuanyuan Wan; Minbo Lan

Advanced Materials Letters, 2011, Volume 2, Issue 3, Pages 172-175
DOI: 10.5185/amlett.2011.1210

Novel spin-labeled magnetic nanoparticles (MNPs) were prepared through the reaction between carboxylic acids modified Fe3O4 particles and 4-amino-2,2,6,6-tetramethylpiperidin-1-oxyl (4-NH2-TEMPO). And X-ray diffractometer (XRD), FT-IR spectra, thermogravimetric analysis (TGA), transmission electronic microscopy (TEM) and room temperature electron paramagnetic resonance (EPR) were employed to characterize the prepared materials. The results of EPR measurements indicated that the spin-labeled MNPs exhibited both the paramagnetism of nitroxide free radicals and superparamagnetism of ferrimagnetic nanoparticles could act as a bio-probe or potential drug delivery vehicles tracking by EPR technique.

Carboxymethyl Chitosan And Its Applications

V.K Mourya; Nazma N. Inamdara;Ashutosh Tiwari

Advanced Materials Letters, 2010, Volume 1, Issue 1, Pages 11-33
DOI: 10.5185/amlett.2010.3108

Deacetylation of chitin affords chitosan, a polymer, widely studied for its pharmaceutical and nonpharmaceutical applications. The hurdle in comprehending these applications is its limited solubility. Carboxymethylation of chitosan helps to surmount this hurdle with its improved solubility in water. Though there is ample of research related to carboxymethyl chitosan (CMC) the focused review of the topic is unavailable. Hence an attempt is made in this review to cover the recent findings pertaining to synthesis, characterization of CMC and its applications especially in pharmaceutical field. CMC has been synthesized by ways as direct alkylation, reductive alkylation, Michael addition and characterized by FTIR, NMR spectroscopy, and DSC, titrimetry, viscometry, gel permeation chromatography, X-ray diffraction and capillary zone electrophoresis. The carboxymethyl group can be present at O or N or both the atoms of chitosan molecule. The CMC possess modulated physical and biological properties as chelating, sorption, moisture retention, cell functioning antioxidant, antibacterial, antiapoptotic etc. CMC is used in sustained or controlled release drug delivery, pH responsive drug delivery, DNA delivery as permeation enhancer etc. CMC can be further modified with alkylation, acylation, and grafting. Carboxyalkylation of chitosan yield carboxyethyl, carboxybutyl chitosans. These analogues of CMC may be helpful in substantiating the applications of chitosan.