Cellulose-based polymeric systems in drug delivery.

2017 ◽  
pp. 10-21
Author(s):  
M Bhanu ◽  
K Harsha ◽  
M. P. Yadav
Keyword(s):  
Drug Delivery ◽  
Polymeric Systems

Biopolymers with Medical Applications Optimized method for obtaining chitosan-based delivery systems

2018 ◽  
Vol 69 (7) ◽  
pp. 1756-1759 ◽  
Author(s):  
Luminita Confederat ◽  
Iuliana Motrescu ◽  
Sandra Constantin ◽  
Florentina Lupascu ◽  
Lenuta Profire
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Average Diameter ◽  
Delivery Systems ◽  
Cross Linking ◽  
Low Molecular Weight ◽  
Polymeric Systems ◽  
Chitosan Microparticles ◽  
Degree Of Swelling

The aim of this study was to optimize the method used for obtaining microparticles based on chitosan � a biocompatible, biodegradable, and nontoxic polymer, and to characterize the developed systems. Chitosan microparticles, as drug delivery systems were obtained by inotropic gelation method using pentasodiumtripolyphosphate (TPP) as cross-linking agent. Chitosan with low molecular weight (CSLMW) in concentration which ranged between 0.5 and 5 %, was used while the concentration of cross-linking agent ranged between 1 and 5%. The characterization of the microparticles in terms of shape, uniformity and adhesion was performed in solution and dried state. The size of the microparticles and the degree of swelling were also determined. The structure and the morphology of the developed polymeric systems were analyzed by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM).The average diameter of the chitosan microparticles was around 522 �m. The most stable microparticles were obtained using CSLMW 1% and TPP 2% or CSLMW 0.75%and TPP 1%. The micropaticles were spherical, uniform and without flattening. Using CSLMW in concentration of 0.5 % poorly cross-linked and crushed microparticles have been obtained at all TPP concentrations. By optimization of the method, stable chitosan-based micropaticles were obtained which will be used to develop controlled release systems for drug delivery.

scholarly journals Development of Photoinitiated Nitric Oxide Releasing Polymer Films for Controlled Drug Delivery

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
D. M. Smeenge ◽  
M. J. Barron ◽  
M. T. Nielsen ◽  
J. Goldman ◽  
M. C. Frost
Keyword(s):  
Nitric Oxide ◽  
Drug Delivery ◽  
Smooth Muscle ◽  
Cell Cultures ◽  
Polymer Films ◽  
Surface Flux ◽  
Surface Fluxes ◽  
No Donors ◽  
Polymeric Systems ◽  
Smooth Muscle Cell Cultures

Nitric Oxide (NO) is small, free radical gas that has been shown to have a wide variety of physiological functions, including the ability to hinder tumor angiogenesis at high, but non lethal, concentrations [1]. Previous work suggests that if NO could be effectively delivered in vivo to tumors of patients currently undergoing chemotherapy treatments at the appropriate levels, less damaging chemotherapy treatments could be used against cancer [2]. This could increase the overall survivability of cancer patients, especially in those prone to the harmful effects of chemotherapy: children, elderly, and those of weak immune systems. If NO is especially successful at preventing and eliminating tumor growth, angiogenesis, and carcinogenesis the need for stressful chemotherapy treatments could be eliminated altogether. This project is focused on developing novel photosensitive NO donors that can be incorporated into polymeric systems and used in a fiber optic drug delivery system. Development of these NO-releasing polymers will allow continued investigation of NO's role in tumor death by precisely controlling the surface flux of NO that cells are exposed to. Generating specific surface fluxes of NO from polymer films has been demonstrated by using polymer films that contain photoinitiated NO donors [3], prepared by synthesizing S-nitrosothiol (RSNO) derivitized polymer fillers that are blended into hydrophobic polymers and cast into a film. These films generate and sustain a surface flux of NO based on the wavelength and intensity of light used [3]. Polymers releasing NO are more promising as an NO donor than simply injecting NO into samples because they allow for spatial and temporal control of NO delivery. The specific concentration of NO needed to produce desirable effects on tumor cells (i.e., apoptosis) is not known. Data will be presented that show the synthesis and NO-release properties of novel RSNOs based on the nitrosation of benzyl mercaptan thiols. Specifically, UV-Vis spectrum of benzyl mercaptan in toluene and S-nitrosobenzyl mercaptan after the addition of t-butyl nitrite will be presented. We are currently investigating the effects of varying NO-surface fluxes generated from photolytic NO donating polymer films on aortic smooth muscle cell cultures obtained from mice. Once we have established that we can quantitatively determine the effects of different levels of NO on the proliferation of smooth muscle cell cultures, work will begin to apply this methodology and these novel NO-releasing polymeric systems to begin investigating what durations and surface fluxes of NO are necessary to have tumorcidal effects on specific cancer cells.

scholarly journals Development of Photoinitiated Nitric Oxide Releasing Polymer Films for Controlled Drug Delivery

2009 ◽  
Vol 3 (2) ◽  
Author(s):  
D. M. Smeenge ◽  
M. C. Frost
Keyword(s):  
Nitric Oxide ◽  
Drug Delivery ◽  
Smooth Muscle ◽  
Cell Cultures ◽  
Polymer Films ◽  
Surface Flux ◽  
Surface Fluxes ◽  
No Donors ◽  
Polymeric Systems ◽  
Smooth Muscle Cell Cultures

Nitric Oxide (NO) is small, free radical gas that has been shown to have a wide variety of physiological functions, including the ability to hinder tumor angiogenesis at high, but non lethal, concentrations. Previous work suggests that if NO could be effectively delivered in vivo to tumors of patients currently undergoing chemotherapy treatments at the appropriate levels, less damaging chemotherapy treatments could be used against cancer. This could increase the overall survivability of cancer patients, especially in those prone to the harmful effects of chemotherapy: children, elderly, and those of weak immune systems. If NO is especially successful at preventing and eliminating tumor growth, angiogenesis, and carcinogenesis the need for stressful chemotherapy treatments could be eliminated altogether. This project is focused on developing novel photosensitive NO donors that can be incorporated into polymeric systems and used in a fiber optic drug delivery system. Development of these NO-releasing polymers will allow continued investigation of NO's role in tumor death by precisely controlling the surface flux of NO that cells are exposed to. Generating specific surface fluxes of NO from polymer films has been demonstrated by using polymer films that contain photoinitiated NO donors, prepared by synthesizing S-nitrosothiol (RSNO) derivitized polymer fillers that are blended into hydrophobic polymers and cast into a film. These films generate and sustain a surface flux of NO based on the wavelength and intensity of light used. Polymers releasing NO are more promising as an NO donor than simply injecting NO into samples because they allow for spatial and temporal control of NO delivery. The specific concentration of NO needed to produce desirable effects on tumor cells (i.e. apoptosis) is not known. Data will be presented that show the synthesis and NO-release properties of novel RSNOs based on the nitrosation of benzyl mercaptan thiols. Specifically, UV-Vis spectrum of benzyl mercaptan in toluene and S-nitrosobenzyl mercaptan after the addition of t-butyl nitrite will be presented. We are currently investigating the effects of varying NO-surface fluxes generated from photolytic NO donating polymer films on aortic smooth muscle cell cultures obtained from mice. Once we have established that we can quantitatively determine the effects of different levels of NO on the proliferation of smooth muscle cell cultures, work will begin to apply this methodology and these novel NO-releasing polymeric systems to begin investigating what durations and surface fluxes of NO are necessary to have tumorcidal effects on specific cancer cells.

scholarly journals The Synthesis of Peptide-Conjugated Poly(2-Ethyl-2-Oxazoline)-bpoly(L-Lactide) (PEtOx-B-PLA) Polymeric Systems Through the Combination of Controlled Polymerization Techniques and Click Reactions

2020 ◽  
Author(s):  
Umut Ugur Ozkose ◽  
Sevgi Gulyuz ◽  
Melek Parlak Khalily ◽  
Salih Ozcubukcu ◽  
Asuman Bozkır ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Drug Targeting ◽  
Drug Delivery Systems ◽  
Delivery Systems ◽  
Controlled Polymerization ◽  
Terminal Position ◽  
Click Reactions ◽  
Polymeric Systems ◽  
Pharmaceutical Agents ◽  
Tumour Homing

To optimize the therapeutic effect of pharmaceutical agents, drug delivery systems tailored from FDA-approved polymers like poly(L-lactide) (PLA) is an effective strategy. Because of their hydrophobic character, these systems greatly suffer from reduced circulation time thus, amphiphilic block copolymers became favourable to overcome this limitation. Of them, poly(oxazoline)-b-poly(L-lactide) are of choice as poly(oxazoline) (PEtOx) is compatibile, biodegradable, while exhibiting minimum cytotoxicity. To tailor selective drug targeting drug delivery systems, whereby their selectivity for tumour tissues is maximised, these polymers should be decorated with so-called tumour-homing agents, such as antibodies, peptides and so forth. To this respect, we designed a new block copolymer, allyl-poly(2-ethyl-2-oxazoline)-b-poly(L-lactide) allyl-(PEtOx-b-PLA) and its subsequent conjugation to tumour-homing peptides, peptide-18 and peptide-563 at the terminal position. In this manuscript, we report our synthetic route to obtain this building block and its conjugation to tumour-homing agents.

scholarly journals A Recent Overview: In Situ Gel Smart Carriers for Ocular Drug Delivery

2021 ◽  
Vol 11 (6-S) ◽  
pp. 195-205
Author(s):  
Mandeep Singh ◽  
Dhruv Dev ◽  
D.N. Prasad
Keyword(s):  
Drug Delivery ◽  
Delivery Systems ◽  
Eye Drops ◽  
Adhesive Properties ◽  
In Situ Gel ◽  
Temperature Changes ◽  
Polymeric Systems ◽  
Protective Layers ◽  
In Situ Gelling

Delivery of the drug to the ocular area is blocked by the protective layers covering the eyes; it has always been a major problem to find effective bioavailability of the active drug in the ocular area due to the short duration of precorneal majority ocular stay. Direct delivery systems combine as well as oil, solution, and suspension, as a result, many delivery systems are not able to effectively treat eye diseases. Many works have been done and are being done to overcome this problem one of which is to use in-situ to build polymeric systems. Ocular In-situ gelling systems are a new class of eye drug delivery systems that are initially in solution but are quickly transformed into a viscous gel when introduced or inserted into an ocular cavity where active drugs are released continuously. This sol-to-gel phase conversion depends on a variety of factors such as changes in pH, ion presence, and temperature changes. Post-transplanting gel selects viscosity and bio-adhesive properties, which prolongs the gel's stay in the ocular area and also releases the drug in a long and continuous way unlike conventional eye drops and ointments. This review is a brief overview of situ gels, the various methods of in situ gelling systems, the different types of polymers used in situ gels, their gel-based methods, and the polymeric testing of situ gel. Keywords: In-situ gel, Polymers, and ion triggered in-situ gel, Mechanism, Evaluation parameters

scholarly journals Biodegradable Polymeric Nanoparticles for Drug Delivery to Solid Tumors

2021 ◽  
Vol 12 ◽  
Author(s):  
Agnese Gagliardi ◽  
Elena Giuliano ◽  
Eeda Venkateswararao ◽  
Massimo Fresta ◽  
Stefania Bulotta ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Polymeric Nanoparticles ◽  
Chemical Properties ◽  
Anticancer Compounds ◽  
Polymeric Systems ◽  
Physico Chemical ◽  
Specific Tumor ◽  
Tumor Tissues ◽  
Therapeutic Molecules ◽  
Biopharmaceutical Properties

Advances in nanotechnology have favored the development of novel colloidal formulations able to modulate the pharmacological and biopharmaceutical properties of drugs. The peculiar physico-chemical and technological properties of nanomaterial-based therapeutics have allowed for several successful applications in the treatment of cancer. The size, shape, charge and patterning of nanoscale therapeutic molecules are parameters that need to be investigated and modulated in order to promote and optimize cell and tissue interaction. In this review, the use of polymeric nanoparticles as drug delivery systems of anticancer compounds, their physico-chemical properties and their ability to be efficiently localized in specific tumor tissues have been described. The nanoencapsulation of antitumor active compounds in polymeric systems is a promising approach to improve the efficacy of various tumor treatments.

Stimuli-Responsive Polymeric Systems for Smart Drug Delivery

2020 ◽  
pp. 115-134
Author(s):  
Dariana Aristizabal Bedoya ◽  
Francisco N. Figueroa ◽  
Micaela A. Macchione ◽  
Miriam C. Strumia
Keyword(s):  
Drug Delivery ◽  
Stimuli Responsive ◽  
Polymeric Systems ◽  
Smart Drug ◽  
Smart Drug Delivery
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