We are introducing a versatile computerized approach to model and simulate polymer tacticities using seven single-stage statistical models. The theory behind the models, e.g., Bovey's versus Price's, Bernoullian, 1st or 2nd order Markovian, enantiomeric types, and combinations thereof is explained. One of the models, "E-B gen", which can be used to produce four types of enantiomorphically controlled tacticities, and the pentad distribution for the model "E-M1" are reported here for the first time. The relations of chain-end controlled models to binary copolymerizations are discussed in detail, and equations for the conversion of tacticity based probabilities to reactivity ratios to obtain related n-ad distributions are presented. The models were applied to 20 polymers with exemplary tacticities found in the literature. A related software program ("Polytact") based on Microsoft's Excel has been designed to calculate all relevant characteristics of the polymer tacticity and to present them in graphical form in a user-friendly manner. The program can be used to produce graphs of the triad, pentad and sequence length distributions and a simulation of 50 monomer repeat units in the polymer for each of the seven models. One of the main intended uses of the program is to compare the computed n-ad distributions to those of experimental polymers obtained from NMR spectroscopy and to gain insight into the polymerization mechanisms.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/s00894-010-0880-8 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Disturbed bone marrow adiposity in patients with Cushing's syndrome and glucocorticoid- and postmenopausal- induced osteoporosis.
Front Endocrinol (Lausanne)
October 2023
Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
Background: Skeletal stem/progenitor cells (SSPCs) in the bone marrow can differentiate into osteoblasts or adipocytes in response to microenvironmental signalling input, including hormonal signalling. Glucocorticoids (GC) are corticosteroid hormones that promote adipogenic differentiation and are endogenously increased in patients with Cushing´s syndrome (CS). Here, we investigate bone marrow adiposity changes in response to endogenous or exogenous GC increases.
View Article and Find Full Text PDFChangeable net charge on nanoparticles facilitates intratumor accumulation and penetration.
J Control Release
June 2022
Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259, Nagatsuta, Midori-Ku, Yokohama, Kanagawa 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259, Nagatsuta, Midori-Ku, Yokohama, Kanagawa 226-83, Japan; Innovation Center of NanoMedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-ku, Kawasaki 212-0821, Japan. Electronic address:
The Enhanced Permeability and Retention (EPR) effect is a golden strategy for the nanoparticle (NP)-based targeting of solid tumors, and the surface property of NPs might be a determinant on their targeting efficiency. Poly(ethylene glycol) (PEG) is commonly used as a shell material; however, it has been pointed out that PEG-coated NPs may exhibit accumulation near tumor vasculature rather than having homogenous intratumor distribution. The PEG shell plays a pivotal role on prolonged blood circulation of NPs but potentially impairs the intratumor retention of NPs.
View Article and Find Full Text PDFPhotodynamic therapy using LCST polymers exerting pH-responsive isothermal phase transition.
J Control Release
December 2020
Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan; Department of Life Science and Technology, School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsutacho, Midori-ku, Yokohama, Kanagawa 226-8503, Japan; Innovation Center of Nanomedicine (iCONM), Kawasaki Institute of Industrial Promotion, 3-25-14 Tonomachi, Kawasaki-ku, Kawasaki, Kanagawa 210-0821, Japan. Electronic address:
In photodynamic therapy (PDT), the inherent physicochemical properties of a photosensitizer (PS) critically affect its biodistribution and therapeutic outcome as well as side effect. Here, we developed a PS-polymer conjugate displaying isothermal hydrophilic-to-hydrophobic phase transition in response to tumorous acidic pH. The polymer backbone was poly(N-isopropylacrylamide (NIPAAm)/2-aminoisoprpylacrylamide (AIPAAm)) (P(NIPAAm/AIPAAm)), which shows lower critical solution temperature (LCST) of 30 °C.
View Article and Find Full Text PDFPolymeric modification of gemcitabine via cyclic acetal linkage for enhanced anticancer potency with negligible side effects.
Biomaterials
March 2020
Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, R1-11, 4259, Nagatsuta, Midori-Ku, Yokohama, Kanagawa, 226-8503, Japan. Electronic address:
Gemcitabine (GEM) is a powerful anticancer drug for various cancers. However, the anticancer efficacy and the side effects should be addressed for effective therapeutics. To this end, we created a GEM-conjugated polymer (P-GEM) based on cyclic acetal linkage as a delivery carrier of GEM.
View Article and Find Full Text PDFEpirubicin-loaded polymeric micelles effectively treat axillary lymph nodes metastasis of breast cancer through selective accumulation and pH-triggered drug release.
J Control Release
December 2018
Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa 226-8503, Japan; Innovation Center of NanoMedicine, Kawasaki Institute of Industrial Promotion, 3-25-14, Tonomachi, Kawasaki-ku, Kawasaki 210-0821, Japan. Electronic address:
Suppression of axillary lymph node metastasis (ALNM) is an important goal in the treatment of breast cancer. While several therapies directed to ALNM have been evaluated, effective and safe treatments for ALNM in triple negative breast cancer (TNBC) have not been established yet, especially against initial/small metastases. Here, we demonstrated the therapeutic effect of an anthracycline drug, epirubicin (EPI)-loaded polymeric micelles equipped with pH-triggered drug release property (EPI/m) against ALNM of TNBC.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!