China
Africa
Explore chapters and articles related to this topic
Application of Bioresponsive Polymers in Drug Delivery
Published in Deepa H. Patel, Bioresponsive Polymers, 2020
Manisha Lalan, Deepti Jani, Pratiksha Trivedi, Deepa H. Patel
Electro-responsive drug release from electro-conductive hydrogels was explored from semi-interpenetrating networks containing a blend of poly[ethyleneimine) and 1-vinylimidazole polymer as the novel electro-active species. The semi-interpenetrating networks are systems comprised of poly(acrylic acid) (PAA) and poly(vinyl alcohol). It was observed in the study that the relative ratios of the two polymers in the blend markedly influenced the degree of electro-responsive drug release and the matrix resilience of the hydrogels. The absence of an electric field resulted in low fluctuation flexibility and thus a highly stable molecular architecture. The use of an electric-stimulus offers versatility in usage of stimulus in terms of the duration of electric pulses, intervals between pulses, magnitude of current, etc. This gives an opportunity for precise control over the changes in physical structure. A number of polymers may be used as electroactive polymers like polypyrrole, polythiophene, polydimethylsiloxane, poly(methyl methacrylate), poly(3,4-ethylene dioxythiophene) and polyvinyl alcohol. These polymers have characteristic redox properties which render them semiconducting in nature and allow controlled ionic transport through the polymeric membrane. They allow for drug transport in the presence of an electric field only where they become resilient in nature and the drug release ceases in its absence. They may be used for continuous, pulsed, triggered drug delivery applications [9].
Stimulus-Receptive Conductive Polymers for Tissue Engineering
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Poly (3,4-ethylenedioxythiophene) (PEDOT), the most effective polythiophene derivative, is a biocompatible conducting polymer which is recently being employed in biomedical applications, especially in nerve tissue engineering. PEDOT has shown its biocompatible properties which exhibit very low intrinsic cytotoxicity and inflammatory response upon implantation with wide range of cell types, including epithelial cells, NIH3T3 and L929 fibroblasts (Zhang et al. 2007), and neural (Castano et al. 2004) and neuroblastoma cells (Olayo et al. 2008). PEDOT-coated PET nanofibers fabricated by Bolin et al. showed excellent human neuroblastoma SH-SY5Y cellular adhesion and proliferation (Mattioli-Belmonte et al. 2003), while PEDOT-coated platinum electrodes exhibited non-cytotoxic effects and no significant differences in immunological response in cortical tissue in comparison to pure platinum controls.
Saliva diagnostics: emerging techniques and biomarkers for salivaomics in cancer detection
Published in Expert Review of Molecular Diagnostics, 2022
Jieren Liu, Dongna Huang, Yuanzhe Cai, Zhihua Cao, Zhiyu Liu, Shuo Zhang, Lin Zhao, Xin Wang, Yuchuan Wang, Feijuan Huang, Zhengzhi Wu
A novel optical microfluidic biosensor with polythiophene (Figure 6A) was developed by Tao et al. It showed good analytical performance for salivary IL-8, IL-1β and MMP-8 with low detection limit, high detection specificity and reproducibility [159]. For the detection of oral cancer biomarker (CYFRA-21-1) in human saliva, Kumar et al. synthesized hafnium oxide nanoparticles by a low-temperature hydrothermal method, developed a non-invasive, label-free immunosensor (Figure 6B) based on nanostructured hafnium oxide (hafnia) and validated the sensor with high sensitivity [160]. Elif et al. fabricated a sensitive and label-free impedance immunosensor (Figure 6C) based on a 6-phosphonohexanoic acid (PHA) modified ITO electrode for the detection of IL-8 in human serum and saliva, achieving a low detection limit of 6 fg/mL [161]. Rong-NaMa and colleagues designed a unique and versatile ratiometric electrochemical DNA biosensor (Figure 6D) for the detection of overexpressed DNA species associated with oral cancer in saliva, achieving a detection limit of 12.8 fM over a linear range of 0.02 pM to 2 nM [162]. In Table 4 below we summarized the latest biosensor devices for detecting specific biomarkers associated with cancers.
Development and characterization of a novel conductive polyaniline-g-polystyrene/Fe3O4 nanocomposite for the treatment of cancer
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Lida Ahmadkhani, Ebrahim Mostafavi, Samaneh Ghasemali, Roghayeh Baghban, Hamidreza Pazoki-Toroudi, Soodabeh Davaran, Javad Malakootikhah, Nahideh Asadi, Lala Mammadova, Siamak Saghfi, Thomas J. Webster, Abolfazl Akbarzadeh
Conducting polymers (CPs) are significant because of their relatively easy processability, thermal and environmental stabilities and tunable electrical conductivities, for example, polyaniline (PANI) [11], polypyrrole (PPy) [12] and polythiophene (PTP) [13,14]. Conducting polymers may have potential applications in areas such as composite materials, tissue engineering, separation membranes, surface-activation materials, supercapacitor, electronic and electro-optic devices, as well as molecular motors [15–17]. Novel advances in polymer engineering have certainly increased the investigation of nanostructured CPs [18,19]. A new challenge in this area of nanotechnology is the capability to synthesize relatively small monodispersed CPs nanostructures, and their composites with metal oxide nanoparticles that have multifunctional properties [11,20–23].
Recent approaches to ameliorate selectivity and sensitivity of enzyme based cholesterol biosensors: a review
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Anjum Gahlaut, Vinita Hooda, Vikas Dhull, Vikas Hooda
Polymers have gained great deal of scientific attention to be used as support for enzyme immobilization. More specifically the conducting polymers have gathered considerable interest due to their high-electrical conductivity, optical properties and mechanical strength. Conducting polymers like polypyrrole (PPy), polyaniline (PANI), polythiophene (PT) can be synthesized chemically by electrochemical polymerization [27]. These properties of polymers are exploited by using polymer matrix in transducer for enhancing the signal response and stability of biosensor. Cholesterol hydrolysing enzymes ChO and ChE has been immobilized on conducting polypyrrole films [28], PB/Polypyrrole (PPy) composite film [29], electropolymerized PPy films [30], poly(3-thiopheneacetic acid film/Pt electrode [31] and PANI–pTSA-Ag/ITO [32]. Chitosan (CS) is a green polymer due to its biodegradability and biocompatibility. It also shows high affinity for proteins and availability of reactive functional groups for chemical modifications which make it a perfect enzyme immobilization support [33]. Transducers have been fabricated using nano ZnO film on chitosan [34], Pt-Pd NPs-CS-GS nanocomposite [35], CNT-CS/GCE [36]. Along with conducting polymers non conducting matrices are suitable for enzyme immobilization. PVC is chemically inert insulating matrix. It has also been used to immobilize cholesterol hydrolysing enzymes. ChO and ChE were covalently immobilized on surface of PVC beaker which act as reaction cell and HRP was incorporated in carbon electrode [37].