Preparation and Characterization of Camptothecin Grafted Chitosan Oligosaccharide Nanomicelles (original) (raw)

Anticancer activity of starch/poly[N-(2-hydroxypropyl)methacrylamide]: biomaterial film to treat skin cancer

International journal of biological macromolecules, 2014

In the present work, films of pHPMA, pHPMAS hybrid, pHPMA-CPT and pHPMAS-CPT hybrid were prepared by solvent casting method and characterized by FT-IR, FT-Raman, XRD and DSC, respectively. The biocompatibility of the prepared pHPMA film and pHPMAS hybrid film were assessed using VERO cell lines and the percentage cell viability was found to be 97.4 and 98.3% for 7.8 μg/ml of the film extracts after 72 h of incubation. The cancer cell viability of the pHPMA-CPT film and pHPMAS-CPT film using MCF7 cell lines at pH 5.5 and 7.4 were found to be 4.9 and 8.6% and 7.7 and 12.3%, respectively. In vitro release of camptothecin from pHPMA-CPT and pHPMAS-CPT films in phosphate-buffered saline solution at pH 5.5 and 7.4 were monitored and analyzed using UV-vis spectrophotometer at λmax of 360 nm.

Temperature-sensitive polymers for drug delivery

Expert Review of Medical Devices, 2012

International Standard Book Number-13: 978-0-8247-2532-7 (Hardcover) This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use.

Synthesis, Morphology, and Rheological Evaluation of HPMA (N-2-Hydroxypropyl Methacrylamide)-PCL (Polycaprolactone) Conjugates

ACS Omega, 2021

The design, synthesis, and physicochemical characterization of conjugates are arduous and tedious processes. Several synthetic pathways for polymeric conjugation have been reported; however, conjugation through monomers with suitable reaction conditions can be a simple and robust approach. In the present study, three different conjugates of hydrophilic N-2-hydroxypropyl methacrylamide (HPMA) and hydrophobic polycaprolactone (PCL) were synthesized. The followed synthetic pathway not only was simple and robust but also reduced the overall synthetic steps as well as harsh reaction conditions significantly. In a nutshell, three conjugates, i.e., N-2-hydroxypropyl methacrylamide and polycaprolactone (HP-PCL), nbutanol-polycaprolactone-N-2-hydroxypropyl methacrylamide (nBu-PCL-HP), and isoamyl alcohol-polycaprolactone-N-2-hydroxypropyl methacrylamide (ISAL-PCL-HP), were synthesized through this simple synthetic strategy following the monomer conjugation approach along with exhaustive spectroscopic and rheological characterization. The conjugates HP-PCL, nBu-PCL-HP, and ISAL-PCL-HP were characterized by Fourier transform infrared (FT-IR) and NMR (13 C and 1 H) spectroscopies. The size and ζ potential of conjugates were determined through the dynamic light scattering (DLS) method. The nBu-PCL-HP conjugate displayed a hexagonal-like shape, as evidenced by scanning electron microscopy (SEM) with an obtained size of 237.9 ± 0.21 nm. X-ray diffraction (XRD) analysis proved the crystalline nature of nBu-PCL-HP conjugates. The results of smartly synthesized conjugates intrigued us to study their flow properties in detail. Rheological evaluation resulted in their non-Newtonian type of flow with the best-fit behavior for all of the conjugates followed as per the Herschel−Bulkley and power-law models applied herein. Conclusively, the synthesized HPMA and PCL conjugates may have applications in the preparation of blends, fibers, etc. in the future. The study portrayed that the explored synthetic scheme using monomers and initiators could be a suitable approach for the synthesis of HPMA and PCL conjugates.

Polymer-Based Prodrugs: Improving Tumor Targeting and the Solubility of Small Molecule Drugs in Cancer Therapy

2015

The majority of anticancer drugs have poor aqueous solubility, produce adverse effects in healthy tissue, and thus impose major limitations on both clinical efficacy and therapeutic safety of cancer chemotherapy. To help circumvent problems associated with solubility, most cancer drugs are now formulated with co-solubilizers. However, these agents often also introduce severe side effects, thereby restricting effective treatment and patient quality of life. A promising approach to addressing problems in anticancer drug solubility and selectivity is their conjugation with polymeric carriers to form polymer-based prodrugs. These polymer-based prodrugs are macromolecular carriers, designed to increase the aqueous solubility of antitumor drugs, can enhance bioavailability. Additionally, polymer-based prodrugs approach exploits unique features of tumor physiology to passively facilitate intratumoral accumulation, and so improve chemodrug pharmacokinetics and pharmacological properties. Th...

Do HPMA copolymer conjugates have a future as clinically useful nanomedicines? A critical overview of current status and future opportunities☆

Advanced Drug Delivery Reviews, 2010

N-(2-Hydroxypropyl)methacrylamide (HPMA) copolymer conjugates containing doxorubicin designed in the late 1970s/early 1980s as anticancer polymer therapeutics were the first synthetic polymer-based anticancer conjugates to enter clinical trial beginning in 1994. Early clinical results were promising, confirming activity in chemotherapy refractory patients and the safety of HPMA copolymers as a new polymer platform in this setting. Subsequent Phase I/II trials have investigated conjugates containing paclitaxel (PNU 166945), camptothecin (PNU 166148) (both failed in clinical trials underlining the importance of rational design), and most recently HPMA-copolymer platinates (AP5280 and then AP5346-ProLindac TM) entered Phase II clinical development. There are a growing array of second generation HPMA copolymer-based systems involving combination therapy, incorporating putative targeting ligands, having an ever more complex architecture, and both drug and protein conjugates are being proposed as novel treatments for diseases other than cancer. Despite their promise, and the success of polymeric drugs and polymer-protein conjugates, no polymer-drug conjugate (HPMA copolymer-based or otherwise) has yet entered routine clinical use. It is timely to reflect on the progress made over the last 30 years, the relative merits of HPMA copolymers as a platform compared to other polymeric carriers, and comment on their future potential as polymer-based nanomedicines into the 21st century in comparison with the many alternative strategies now emerging for creation of nanopharmaceuticals.

Polymeric anticancer drugs with pH-controlled activation

Advanced Drug Delivery Reviews, 2004

Use of macromolecular water-soluble carriers of anti-cancer drugs represents a promising approach to cancer therapy. Release of drugs from the carrier system is a prerequisite for therapeutic activity of most macromolecular anti-cancer conjugates. Incorporation of acid-sensitive spacers between the drug and carrier enables release of an active drug from the carrier in a tumor tissue, either in slightly acidic extracellular fluids or, after endocytosis, in endosomes or lysosomes of cancer cells. This paper reviews advances in development and study of properties of various acid-sensitive macromolecular drug delivery systems, starting from simple polymer -drug conjugates to ending with site-specific antibody-targeted polymer -drug conjugates. D

Polymeric nanohybrids and functionalized carbon nanotubes as drug delivery carriers for cancer therapy

Advanced Drug Delivery Reviews, 2011

The scope of nanotechnology to develop target specific carriers to achieve higher therapeutic efficacy is gaining importance in the pharmaceutical and other industries. Specifically, the emergence of nanohybrid materials is posed to edge over chemotherapy and radiation therapy as cancer therapeutics. This is primarily because nanohybrid materials engage controlled production parameters in the making of engineered particles with specific size, shape, and other essential properties. It is widely expressed that these materials will significantly contribute to the next generation of medical care technology and pharmaceuticals in areas of disease diagnosis, disease prevention and many other treatment procedures. This review focuses on the currently used nanohybrid materials, polymeric nanoparticles and nanotubes, which show great potential as effective drug delivery systems for cancer therapy, as they can be grafted with cell-specific receptors and intracellular targeting molecules for the targeted delivery of therapeutics. Specifically, this article focuses on the current status, recent advancements, potentials and limitations of polymeric nanohybrids and functionalized carbon nanotubes as drug delivery carriers.

Synthesis of Polymer-Drug Conjugates Using Natural Polymer: What, Why and How?

Pharmaceutical Sciences and Research, 2018

For years, natural polymers have played a significant role in pharmaceutical field due to their biocompatibility and biodegradability. In Indonesia, most research in natural polymers focus on application of the polymers as inert pharmaceutical excipients or as drug matrix in micro- and nano- particle. Meanwhile, research about polymers in the world (mostly synthetic polymers) have been progressed to advanced drug delivery system. In this system, the polymer can act as either pharmacologically active molecules, or sophisticated carrier in targeted prodrug delivery system. The latter is called polymer-drug conjugates, a system where the drugs are covalently attached to a polymeric carrier, rather than simply entrapped in polymer matrix. Natural polymers have been one of the materials to use for the carrier due to their biocompatibility and biodegradability. This review article emphasizes the opportunity, challenges and strategies to use natural polymers as carrier in polymer-drug conj...

Camptothecin poly[n-(2-hydroxypropyl) methacrylamide] copolymers in antitopoisomerase-I tumor therapy: intratumor release and antitumor efficacy

Molecular cancer therapeutics, 2003

Soluble copolymers of camptothecin (CPT), based on poly[N-(2-hydroxypropyl) methacrylamide] (pHPMA), were obtained by conjugation through the degradable spacers -Gly-Phe-Leu-Gly- or -Gly-6-aminohexanoyl-Gly-. We investigated to what extent passive accumulation and retention of hydroxypropyl methacrylamide copolymer of CPT (pHPMA-CPT) in tumors and modulation of the drug release influence efficacy. Release of CPT in vivo was detected by time-resolved phase-shift fluorescence imaging on tumor specimens, based on the evidence that free and bound drug had different fluorescence lifetimes in solution. HT-29 murine specimens, obtained at several times after treatment with (3)H-labeled free CPT, pHPMA-Gly-Phe-Leu-Gly-CPT, or pHPMA-Gly-6-aminohexanoyl-Gly-CPT, were either imaged for time-resolved phase-shift fluorescence or subjected to autoradiography. Phase shifts of CPT conjugates were equal or longer than those of free CPT, indicating the presence of both free and polymer-bound drug in ...