Drug Release Test Research Articles

Crosslinked palygorskite-chitosan beads as diclofenac carriers

Beads are versatile spherical drug delivery units that can be coated, filled into capsules or compressed as tablets to be orally administered. Crosslinking of chitosan (CS) and polyanions such as tripolyphosphate (TPP) results in beads with mechanical properties that could be improved by the addition of clay mineral particles to the bead network. Hybrid systems of palygorskite and chitosan have been shown to have advanced properties in biomedical applications as a result of the synergic effects of their combination. In this paper chitosan was intercalated with palygorskite (Pal) and the resultant hybrid was loaded with diclofenac, an anti-inflammatory drug. Chitosan (CS) beads crosslinked with sodium tripolyphosphate (TPP) were prepared and their properties compared to palygorskite/Chitosan (Pal/CS) beads. The synergic effects resulting from the clay/polymer hybrids were evaluated by means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (SEM) and thermal analysis (thermogravimetric analysis, TGA, and differential scanning calorimetry, DSC). The results showed that chitosan and palygorskite interaction took place. Diclofenac sodium (DFNa) was used as model drug to reveal the effects of Pal within the bead structure. DFNa was successfully loaded into beads and FTIR analyses confirmed its presence. A drug release test was carried out in phosphate buffer medium (pH. 6.8). The results indicated that only 33% (w/w) of total drug was released from DFNa-Pal/CS compared to 66% (w/w) from DFNa-CS. The total amount of drug released fell significantly with the addition of palygorskite to the chitosan matrix. Pal/CS beads crosslinked with TPP were shown to be able of carrying diclofenac sodium, meaning they could possibly be used as drug carriers.

Mucoadhesive In Situ Gelling Liquid Crystalline Precursor System to Improve the Vaginal Administration of Drugs.

The vaginal mucosa is a very promising route for drug administration due to its high permeability and the possibility to bypass first pass metabolism; however, current vaginal dosage forms present low retention times due to their dilution in vaginal fluids, which hampers the efficacy of many pharmacological treatments. In order to overcome these problems, this study proposes to develop a mucoadhesive in situ gelling liquid crystalline precursor system composed of 30% of oleic acid and cholesterol (7:1), 40% of ethoxylated and propoxylated cetyl alcohol, and 30% of a dispersion of 16% Poloxamer 407. The effect of the dilution with simulated vaginal fluid (SVF) on this system was evaluated by polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), rheological studies, texture profile analysis (TPA), mucoadhesion study, in vitro drug release test using hypericin (HYP) as drug model, and cytotoxicity assay. PLM and SAXS confirmed the formation of an isotropic system. After the addition of three different concentrations of SVF (30, 50, and 100%), the resultant formulations presented anisotropy and characteristics of viscous lamellar phases. Rheology shows that formulations with SVF behaved as a non-Newtonian fluid with suitable shear thinning for vaginal application. TPA and mucoadhesion assays indicated the formation of long-range ordered systems as the amount of SVF increases which may assist in the fixation of the formulation on the vaginal mucosa. The formulations were able to control about 75% of the released HYP demonstrating a sustained release profile. Finally, all formulations acted as safe vaginal drug delivery systems.

Icariin-Functionalized Coating on TiO2 Nanotubes Surface to Improve Osteoblast Activity In Vitro and Osteogenesis Ability In Vivo

Surface modification of titanium is encouraged to facilitate early osseointegration in dental and orthopedic fields. Icariin is the main active constituents of Herba Epimedii, which has good bone-promoting ability. We established an icariin-functionalized coating composed of icariin and poly (lactic-co-glycolic acid) (PLGA) on TiO2 nanotubes surface (NT-ICA-PLGA) to promote osteoblast cell activity and early osseointegration. Surface topography, wettability and drug release pattern of the established NT-ICA-PLGA surface were characterized by scanning electron microscopy (SEM), contact angle test and drug release test. MC3T3-E1 osteoblast cell activity tests were performed using SEM, immunofluorescent staining, cell counting kit-8 and alkaline phosphatase assays. The osteogenic effects of different surfaces were observed using a rat model. Surface characterization proved the successful fabrication of the icariin-functionalized coating on the TiO2 nanotube structure, with increased wettability. The NT-ICA-PLGA substrate showed sustained release of icariin until two weeks. Osteoblast cells grown on the NT-ICA-PLGA substrate displayed improved cell adhesion, proliferation and differentiation ability than the control Ti surface. The in vivo experiment also revealed superior bone forming ability on the NT-ICA-PLGA surface, compared to the pure Ti control. These results imply that the developed NT-ICA-PLGA substrate has a promising future use as functionalized coating for implant surface modification.

Smart Freeze-Dried Bigels for the Prevention of the Sexual Transmission of HIV by Accelerating the Vaginal Release of Tenofovir during Intercourse.

Sub-Saharan African women are still at risk from the human immunodeficiency virus (HIV), and sex with men is the main route of transmission. Vaginal formulations containing antiretroviral drugs are promising tools to give women the power to protect themselves. The aim of this work was to obtain freeze-dried bigels containing pectin, chitosan, or hypromellose for the vaginal controlled release of Tenofovir, which is accelerated in the presence of semen. Nine batches of bigels were formulated using different proportions of these polymers in the hydrogel (1, 2, and 3% w/w). The bigels obtained were freeze-dried and then underwent hardness and deformability, mucoadhesion, swelling, and drug release tests, the last two in simulated vaginal fluid (SVF) and SVF/simulated seminal fluid (SSF) mixture. The formulation containing 3% pectin (fd3P) has the highest values for hardness, resistance to deformation, and good mucoadhesivity. Its swelling is conditioned by the pH of the medium, which is responsive to the controlled release of Tenofovir in SVF, with the fastest release in the SVF/SSF mixture. fd3P would be an interesting smart microbicidal system to allow faster release of Tenofovir in the presence of semen, and thus increase women’s ability to protect themselves from the sexual transmission of HIV.

Preparation and properties of poly (lactic acid) (PLA) suture loaded with PLA microspheres enclosed drugs (PM-Ds)

Drug loaded PLA suture has been one most potential surgery material to help wounds healing. The loaded drug amounts and sustained drug release effect were a vital part for PLA suture. In this research drug-loaded microspheres and finishing bath were prepared to ensure more drug particles loaded on PLA suture. Moreover, sustained drug release effect and mechanical properties of PLA suture were also observed. The results suggested that PLA concentration and emulsifier amounts had more effect on the size of PLA drug-loaded microspheres and the optimal technology was: 0.03 g/mL of PLA concentration, 0.3 g of amount of emulsifier and the total amount of drug and emulsifier was 3 g. Moreover, drug release test showed a significant sustained release effect of the drug-loaded PLA suture. Mechanical measurements indicated the flexibility and strength were not impaired by such drug-loaded method. This research is expected to benefit the surgery fields further.

Loading zedoary oil into pH-sensitive chitosan grafted mesoporous silica nanoparticles via gate-penetration by supercritical CO2 (GPS)

Nanocarriers of the stimuli-responsive mesoporous silica nanoparticles (MSNs) have exhibited great potential on target-specific and controlled-release drug delivery. However, it is still a challenge to load drugs into this promising nanocarriers because of its gated structure. In this study, we developed a method named gate-penetration by supercritical CO2 (GPS) to successfully prepared zedoary oil loaded chitosan grafted MSNs (ZO@CS-MSNs). Quantitative analysis by high performance liquid chromatography demonstrated the composition ratio of six primary ingredients in zedoary oil remained constant after the drug loading process. Several process parameters of GPS were optimized, and the drug load of ZO reached 41.4 ± 1.2%. Morphology characterization by scanning electron microscope showed that ZO@CS-MSNs were spheres with diameter about 80 nm and a ‘gate’ structure was formed by chitosan on the surface of MSNs. Infrared and thermogravimetric analysis were performed to further confirm the structure of ZO@CS-MSNs. in vitro drug release test under different pH conditions indicated that ZO had a well pH-response release behavior, proving that ZO was transported into the inner channels of MSNs. The results state GPS is a promising way of high-efficacy and non-destructive to overcome the drug loading problems for stimuli-responsive MSN and further extend its application.

Microfluidic Synthesis of Vinblastine-Loaded Multifunctional Particles for Magnetically Responsive Controlled Drug Release.

Vinblastine (VBL) is a major chemotherapeutic drug; however, in some cases, it may cause severe side effects in patients with cancer. Designing a novel VBL pharmaceutical formulation is a crucial and emerging concern among researchers for reducing the use of VBL. This study developed a stimuli-responsive controlled VBL drug release system from magnetically sensitive chitosan capsules. A magnetically responsive controlled drug release system was designed by embedding superparamagnetic iron oxide (SPIO) nanoparticles (NPs) in a chitosan matrix and an external magnet. In addition, droplet microfluidics, which is a novel technique for producing polymer spheres, was used for manufacturing monodispersed chitosan microparticles. The prepared VBL and SPIO NPs-loaded chitosan microparticles were characterized and analyzed using Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, a superconducting quantum interference device, and a biocompatibility test. The drug encapsulation efficiency was 67%–69%. The in vitro drug release test indicated that the VBL could be 100% released from chitosan composite particles in 80–130 min under magnetic stimulation. The pulsatile magnetically triggered tests showed individual and distinctive controlled release patterns. Thus, the timing and dose of VBL release was controllable by an external magnet. The results presume that using a magnetically responsive controlled drug release system offers a valuable opportunity for VBL drug delivery, where the delivery system is an active participant, rather than a passive vehicle, in the optimization of cancer treatment. The proposed actively targeted magnetic drug delivery system offers many advantages over conventional drug delivery systems by improving the precision and timing of drug release, easy operation, and higher compliance for pharmaceutical applications.

Bioinspired Surface Functionalization of Titanium for Enhanced Lubrication and Sustained Drug Release.

Titanium and its alloys have long been used as implantable biomaterials in orthopedics; however, to the best of our knowledge, few studies were reported to investigate surface functionalization of titanium for enhanced lubrication and sustained drug release. In the present study, titania nanotube arrays (TNTs) were prepared by anodization as effective drug nanocarriers, using titanium as the substrate. Meanwhile, motivated by articular cartilage-inspired superlubricity and mussel-inspired adhesion, a copolymer containing both dopamine methacrylamide and 2-methacryloyloxyethyl phosphorylcholine was synthesized (DMA-MPC) and spontaneously grafted onto the TNT surface, which was validated by characterization techniques such as scanning electron microscopy, water contact angle measurements, and X-ray photoelectron spectroscopy. Additionally, the lubrication test showed that copolymer-grafted TNTs have remarkably reduced friction coefficients compared with bare TNTs. Furthermore, the drug release test demonstrated that copolymer-grafted TNTs inhibited burst drug release and achieved sustained drug release in comparison with bare TNTs. In conclusion, the bioinspired surface functionalization strategy developed here, namely DMA-MPC copolymer-grafted TNTs, can be applied to modify orthopedic biomaterials (such as titanium) for enhanced lubrication and sustained drug release.

5‑Fluorouracil loaded chitosan/polyacrylic acid/Fe3O4 magnetic nanocomposite hydrogel as a potential anticancer drug delivery system

In most cancer treatments, chemotherapy is currently necessary; hence, more attention was devoted to developing new methods for designing drug delivery systems (DDS) with controlled drug release. For this aim, anticancer 5‑fluorouracil (5-FU) drug was loaded into chitosan/polyacrylic acid/Fe3O4 magnetic nanocomposite hydrogel (CS/PAA/Fe3O4) through immersing in the drug solution. The prepared CS/PAA/Fe3O4 was characterized using FT-IR, XRD, VSM, TGA and SEM analysis. For demonstrating the efficiency of the prepared novel nanocomposite carrier as a controlled DDS, in-vitro the drug delivery tests were carried out in mimicking the colon and rectal conditions. The drug release tests showed that the CS/PAA/Fe3O4 enhanced the stability of drug dosing for a long time with controlled releases in the colon and rectal conditions. According to the obtained results, the prepared nanocomposite hydrogel could potentially to be used in DDS as a colon and rectal administration of 5-FU.

Self-microemulsifying Drug Delivery System for Improved Oral Delivery of Limonene: Preparation, Characterization, in vitro and in vivo Evaluation.

The current investigation aimed at formulating self-microemulsifying drug delivery system (SMEDDS) to ameliorate oral bioavailability of a hydrophobic functional ingredient, limonene. Solubility test, compatibility test, and pseudo-ternary phase diagrams (PTPD) were adopted to screen the optimal compositions of limonene-SMEDDS (L-SMEDDS). The characteristics of this system assessed in vitro, mainly included determination of particle size distribution, observation of morphology via transmission electron microscopy (TEM), testing of drug release in different dissolution media, and evaluation of stability. The oral bioavailability study in vivo of the formulated limonene was performed in rats with the free limonene as the reference. Compared with the free limonene, the distribution study of L-SMEDDS was conducted in Kunming mice after oral administration. The optimized SMEDDS (ethyl oleate, 14.2%; Cremophor EL, 28.6%; isopropanol, 28.6%; and loaded limonene, 28.6%) under the TEM (about 100nm) was spherical with no significant variations in size/appearance for 30days at 4, 25, and 60°C. In comparison with free limonene, higher than 89.0% of limonene was released from SMEDDS within 10min in different dissolution media. An in vivo study showed a 3.71-fold improved oral bioavailability of the formulated limonene compared to the free limonene. The tissue distribution results showed that limonene predominantly accumulated in the various tissues for the L-SMEDDS compared with the free limonene. Hence, L-SMEDDS could remarkably improve the concentration of limonene in the various organs. These findings hinted that the oral bioavailability of limonene could be improved via an effectual delivery system like SMEDDS.

Molecularly imprinted composite bacterial cellulose nanofibers for antibiotic release

The aim of this work is to develop drug carrier system with high loading capacity and controlled drug release profile for antibiotic release. For this purpose, composite molecularly imprinted nanofibers were prepared via in-situ graft polymerization of methacrylic acid as a monomer, N,N’-methylene bisacrylamide as a crosslinker and gentamicin sulfate as a template molecule onto surface-modified bacterial cellulose nanofibers. Gentamicin imprinted microparticles were fabricated onto bacterial cellulose nanofibers resulting in the formation of composite BC nanofibers. Thus, the composite nanofibers incorporated with gentamicin imprinted microparticles were achieved to fabricated. The in-vitro drug release tests were performed to evaluate the release performance of the resultant composite nanofibers at 37 °C. Also, kinetic models were applied to the drug release data. It was determined that the drug release from the composite molecularly imprinted nanofibers fit well in the Korsmeyer-Peppas model.

Functionalisation of Silicone by Drug-Embedded Chitosan Nanoparticles for Potential Applications in Otorhinolaryngology.

Silicones are widely used medical materials that are also applied for tympanostomy tubes with a trending goal to functionalise the surface of the latter to enhance the healing of ear inflammations and other ear diseases, where such medical care is required. This study focuses on silicone surface treatment with various antimicrobial coatings. Polysaccharide coatings in the form of chitosan nanoparticles alone, or with an embedded drug mixture composed of amoxicillin/clavulanic acid (co-amoxiclav) were prepared and applied onto silicone material. Plasma activation was also used as a pre-treatment for activation of the material’s surface for better adhesion of the coatings. The size of the nanoparticles was measured using the DLS method (Dynamic Light Scattering), stability of the dispersion was determined with zeta potential measurements, whilst the physicochemical properties of functionalised silicone materials were examined using the UV-Vis method (Ultraviolet-Visible Spectroscopy), SEM (Scanning Electron Microscopy), XPS (X-Ray Photoelectron Spectroscopy). Moreover, in vitro drug release testing was used to follow the desorption kinetics and antimicrobial properties were tested by a bacterial cell count reduction assay using the standard gram-positive bacteria Staphylococcus aureus. The results show silicone materials as suitable materials for tympanostomy tubes, with the coating developed in this study showing excellent antimicrobial and biofilm inhibition properties. This implies a potential for better healing of ear inflammation, making the newly developed approach for the preparation of functionalised tympanostomy tubes promising for further testing towards clinical applications.

Nanostructured ZnO as Multifunctional Carrier for a Green Antibacterial Drug Delivery System-A Feasibility Study.

The physico–chemical and biological properties of nanostructured ZnO are combined with the non-toxic and eco-friendly features of the scCO2-mediated drug loading technique to develop a multifunctional antimicrobial drug delivery system for potential applications in wound healing. Two nanostructured ZnO (NsZnO) with different morphologies were prepared through wet organic-solvent-free processes and characterized by means of powder X-ray diffraction, field emission scanning electron microscopy (FESEM), and nitrogen adsorption analysis. The antimicrobial activity of the two samples against different microbial strains was investigated together with the in vitro Zn2+ release. The results indicated that the two ZnO nanostructures exhibited the following activity: S. aureus > C. albicans > K. pneumoniae. A correlation between the antimicrobial activity, the physico–chemical properties (specific surface area and crystal size) and the Zn2+ ion release was found. Ibuprofen was, for the first time, loaded on the NsZnO carriers with a supercritical CO2-mediated drug impregnation process and in vitro dissolution studies of the loaded drug were performed. A successful loading up to 14% w/w of ibuprofen in its amorphous form was obtained. A preliminary drug release test showed that up to 68% of the loaded ibuprofen could be delivered to a biological medium, confirming the feasibility of using NsZnO as a multifunctional antimicrobial drug carrier.

Synthesis and biological evaluation of paclitaxel and vorinostat co-prodrugs for overcoming drug resistance in cancer therapy in vitro.

Paclitaxel (PTX) is the first-line treatment drug for breast cancer. However, drug resistance after a course of treatment and low selectivity restricted its clinical utility sometimes. In this study, we successfully bound PTX and vorinostat (SAHA) to form co-prodrugs based on the synergistic anticancer effects. The PTX-SAHA co-prodrugs were conjugated by glycine (1a) and succinic acid (1b) respectively and the former has shown better activity in cytotoxicity, cell cycle arrest and western-blot experiments. Therefore, 1a was further prepared to nanomicelles with mPEG2000-PLA1750 as the carrier by using thin film method. PTX-SAHA co-prodrug nanomicelles were spherical with a particle size of 20-100 nm. In vitro drug release test showed 1a nanomicelles had sustained release effect, which could reduce the resistance of PTX. In vitro cytotoxicity was evaluated by SRB assay in HCT-116 cells, MCF-7 cells and drug-resistant MCF-7/ADR cells. The results showed 1a nanomicelles had comparable or even better cytotoxicity than PTX especially in the MCF-7/ADR cells. All the results suggested that PTX-SAHA co-prodrug nanomicelles were promising treatment for PTX resistance cancer.

Drug delivery systems using pullulan, a biocompatible polysaccharide produced by fungal fermentation of starch

Advanced drug delivery systems are now designed with biodegradable, biocompatible and non-toxic materials such as polysaccharides. Pullulan is a polysaccharide consisting of maltotriose units. Pullulan is produced from starch by the fungus Aureobasidium pullulans. Pullulan and derivatives are able to conjugate or complex with hydrophobic drugs. Scientists are optimizing the physical interactions and hydrophilic–hydrophobic balance to create systems with controlled loading and targeted delivery of the drugs to cancer cells or liver cell receptors. This article reviews pullulan-based systems of various therapeutic properties. Pullulan structure can be easily modified to transfer various drugs. Pullulan can form microparticles, nanoparticles, micelles, films and hydrogels. Therapeutic properties include antibacterial, antifungal, antitumor, anti-inflammatory, immunomodulatory, antioxidant, antiglycemic, antilipidemic, bone regenerator and systemic protective role. The medical suitability of pullulan-based drug carriers is confirmed by profiles of drug release and cytotoxicity tests carried out in vivo or in vitro.

Uniform carboxymethyl chitosan-enveloped Pluronic F68/poly(lactic-co-glycolic acid) nano-vehicles for facilitated oral delivery of gefitinib, a poorly soluble antitumor compound.

In this study, a new type of biodegradable and stable carboxymethyl chitosan (CCS)-enveloped Pluronic® F68/poly(lactic-co-glycolic acid) (PF/PLGA) nanoparticle (CCS/PF/PLGA NP) was developed, and its potential as an oral delivery vehicle to achieve pH-triggered prolonged release, enhance cellular uptake, and promote oral absorption of poorly soluble antitumor compounds was systemically studied. In this nanocarrier, a PF/PLGA NP serves as the core for effective loading, transport, and prolonged release of a chemotherapeutic agent, while a CCS surface layer acts as the shell and provides pH-responsive and mucoadhesive features. Gefitinib (GEF), an oral poorly soluble chemotherapeutic agent, was selected as the model compound. The prepared GEF-loaded CCS/PF/PLGA (GEF/CCS/PF/PLGA) NPs possessed a monodispersed spherical shape with a uniform size (242 ± 6 nm). Thermal analysis confirmed that GEF/CCS/PF/PLGA NPs were present in an amorphous form. Drug release tests showed that GEF/CCS/PF/PLGA NPs have a pH-responsive prolonged release manner with limited drug release at low gastric pH. Furthermore, the mucoadhesive property, intestinal distribution, cellular uptake, and cytotoxicity of CCS/PF/PLGA NPs were also tested. After oral administration in rats, pharmacokinetic analysis revealed that GEF/CCS/PF/PLGA NPs produced approximately 1.6-fold increased bioavailability of GEF when compared to the commercial trademarked product (Iressa®). In addition, under accelerated stability conditions, the prepared GEF/CCS/PF/PLGA NPs exhibited excellent physicochemical stability. Our results suggest that CCS/PF/PLGA NPs exhibit great potential as an effective and stable oral delivery system for achieving pH-triggered sustained release, enhanced cellular uptake, and improved oral absorption of poorly soluble chemotherapeutic agents, such as GEF.

In Situ Formation of Homogeneous Tellurium Nanodots in Paclitaxel-Loaded MgAl Layered Double Hydroxide Gated Mesoporous Silica Nanoparticles for Synergistic Chemo/PDT/PTT Trimode Combinatorial Therapy.

A folic acid (FA) functional drug delivery system (MT@L-PTX@FA) based on in situ formation of tellurium nanodots (Te NDs) in paclitaxel (PTX)-loaded MgAl layered double hydroxide (LDHs) gated mesoporous silica nanoparticles (MSNs) has been designed and fabricated for targeted chemo/PDT/PTT trimode combinatorial therapy. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), N2 adsorption-desorption, Fourier transform infrared (FT-IR) spectra, and UV-vis spectra were used to demonstrate the successful fabrication of MT@L-PTX@FA. In particular, the in situ generated Te NDs showed a homogeneous ultrasmall size. Reactive oxygen species (ROS) generation, photothermal effects, and photostability evaluations indicated that the in situ generated homogeneous Te NDs could serve as the phototherapeutic agent, converting the photon energy to ROS and heat under near-infrared (NIR) irradiation efficiently. The drug-release test revealed that MT@L-PTX@FA showed an apparent sustained release character in a pH-sensitive manner. In addition, cell imaging experiments demonstrated that MT@L-PTX@FA could selectively enter into cancer cells owing to the function of FA and release of PTX efficiently for chemotherapy for the reason that the low intracellular pH would dissolve MgAl LDHs to Mg2+ and Al3+. Cytotoxicity tests also indicated that MT@L-PTX@FA exhibited enhanced therapeutic effect in cancer cells under NIR irradiation, benefiting from the synergy based on targeted chemo/PDT/PTT trimode combinatorial therapy. The preliminary results reported here will shed new light on the future design and applications of nanosystems for synergistic combinatorial therapy.

Anticancer Nano Formulation of Imatinib with Chitosan Polymer

Objective: Drug targeting is the capacity of the dosage form. In which the therapeutic agent acts specifically to desired site of action in the non-targeted tissue with the help of Nano particles is called as the drug targeting. IMATINIB is a used to treat cancer by chemo therapy. Cancers like chronic myeloid leukemia cancer (CML) and acute lymphoblastic leukemia cancer (ALL) and other specific types of gastrointestinal stromal cell tumor (GIST) systemic mast cell disease and Bone marrow failure disorder. It is administered by oral root. For ATP, Tyrosine kinase is act as a binding site. Methodology: The drug IMATINIB is loaded in the polymer chitosan, poly-(D) glucosamine is a bio compactible, bio degradable, nontoxic, antimicrobial and soluble in solvents. This preparation is done by emulsion-droplet coalescence method. Content of the Drug, Size of the particle and Zeta potential, Encapsulation efficiency and Drug release testing are described for this formulation in this study. Results: The Imatinib Nano particles were formulated and evaluated for its invitro drug release profile. Based on the invitro drug release profile of Imatinib nano particles formulation (INP1 – INP5) formulation INP3 was selected as the best formulation in which the particle size was 285.9nm. The invitro % drug release of INP3 formulation was 99.76 ± 0.82 and it was found to be the suitable formulation to manage the cancer. Conclusion: Hence it is concluded that the newly formulated controlled release nanoparticle drug delivery system of Imatinib may be idol and effective by allowing the drug to release continuously for 24 hrs.

Bi-layered electrospun nanofibrous membrane with osteogenic and antibacterial properties for guided bone regeneration.

Guided bone regeneration (GBR) membranes have the potential to prevent the invasion of epithelial and connective tissues as well as to maintain a stable space for facilitating the ingrowth of regenerative bone tissue. However, the bioactivity and regeneration potential of currently available membranes still need to be improved. In this study, a novel bi-layered membrane with both osteogenic and antibacterial functions was developed for GBR applications. The loose layer (LL) of the membrane was composed of conjugated electrospun poly (lactic-co-glycolic acid) (PLGA)/gelatin nanofibers incorporating dexamethasone-loaded mesoporous silica nanoparticles (DEX@MSNs), while the dense layer (DL) of the membrane consisted of traditionally electrospun PLGA nanofibers loaded with the broad-spectrum antibiotic doxycycline hyclate (DCH). Morphological results showed that the LL (DEX@MSNs/PLGA/Gel) membrane exhibited a porous and loosely packed structure, which was beneficial for cell adhesion and infiltration, while the DL (DCH/PLGA) membrane remained dense enough to act as a barrier. In vitro drug release tests indicated that both DEX and DCH followed a favorable sustained release profile. The cell viability evaluation suggested that the electrospun membranes possessed good cytocompatibility. Furthermore, in vitro osteogenesis analyses demonstrated that the DEX@MSNs/PLGA/Gel composite membrane possessed an enhanced osteoinductive capacity for rat bone marrow stem cells (BMSCs), which was verified by the increased alkaline phosphatase (ALP) activity, the enhanced calcium deposition, and the upregulated osteocalcin (OCN) expression. In vitro antimicrobial experiments revealed the effective antibacterial potency of the DCH/PLGA membrane. In conclusion, the prepared nanocarrier-incorporated bi-layered composite membrane with combined osteogenic and antibacterial properties may be a promising candidate for GBR application.

Hybrid mesoporous silica with controlled drug release

The mesoporous silica particles were prepared by the sol?gel method in one-step synthesis, in acidic conditions, from tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES), varying the mole ratio of the silica precursors. Nitric acid was used as catalyst at room temperature and hexadecyltrimethyl ammonium bromide (CTAB) as structure directing agent. Optical properties, porosity and microstructure of the materials in function of the MTES/TEOS ratio were evaluated using infrared spectroscopy, nitrogen adsorption and small angle X-ray scattering. All materials showed the ordered pore structure and the high specific surfaces, making them suitable as the drug delivery systems. Drug loading and release tests using ketoprofen were performed to assess their performance for drug delivery applications. The amount of the methylated precursor used in the synthesis had little effect on the drug loading capacity, but had a strong influence on the initial rate of the drug release.