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We investigated d-amino acids as potential inhibitors targeting l-peptide toxins. Among the l- and d-amino acids tested, we found that d-tryptophan (d-Trp) acted as an inhibitor of melittin-induced hemolysis. We then evaluated various Trp derivatives and found that 5-chlorotryptamine (5CT) had the largest inhibitory effect on melittin. The indole ring, amino group, and steric hindrance of an inhibitor played important roles in the inhibition of melittin activity. Despite the small size and simple molecular structure of 5CT, its IC

Since castration-resistant prostate cancer (CRPC) acquires resistance to molecularly targeted drugs, discovering a class of drugs with different mechanisms of action is needed for more efficient treatment. In this study, we investigated the anti-tumor effects of nanaomycin K, derived from “Streptomyces rosa subsp. notoensis” OS-3966. The cell lines used were LNCaP (non-CRPC), PC-3 (CRPC), and TRAMP-C2 (CRPC). Experiments included cell proliferation analysis, wound healing analysis, and Western blotting. In addition, nanaomycin K was administered intratumorally to TRAMP-C2 carcinoma-bearing mice to assess effects on tumor growth. Furthermore, immuno-histochemistry staining was performed on excised tissues. Nanaomycin K suppressed cell proliferation in all cell lines (p < 0.001) and suppressed wound healing in TRAMP-C2 (p = 0.008). Nanaomycin K suppressed or showed a tendency to suppress the expression of N-cadherin, Vimentin, Slug, and Ras in all cell lines, and suppressed the phosphorylation of p38, SAPK/JNK, and Erk1/2 in LNCaP and TRAMP-C2. In vivo, nanaomycin K safely inhibited tumor growth (p = 0.001). In addition, suppression of phospho-Erk1/2 and increased expression of E-cadherin and cleaved-Caspase3 were observed in excised tumors. Nanaomycin K inhibits tumor growth and suppresses migration by inhibiting epithelial-mesenchymal transition in prostate cancer. Its mechanism of action is related to the inhibition of phosphorylation of the MAPK signaling pathway.

The high incidence and mortality of cancer make it a global health issue. However, conventional cancer therapies have several disadvantages, especially serious side effects due to low selective toxicity to cancer cells. Gold nanoparticles (AuNPs) are an excellent drug carrier, enhance drug delivery efficiency, and hold promise for photothermal and radiation therapies. (-)-Epigallocatechin-3-gallate (EGCG) is the major polyphenolic antioxidant constituent of green tea, has a potent antitumor effect, and binds specifically to the 67 kDa laminin receptor, which is overexpressed on the surface of several cancer cell lines such as HeLa and MDA-MB-231 cells. We synthesized EGCG-modified AuNPs (EGCG-AuNPs) using ratios (

Polyglycerol dendrimers (PGD) exhibit unique properties such as drug delivery, drug solubilization, bioimaging, and diagnostics. In this study, PGD hydrogels were prepared and evaluated as devices for controlled drug release with good solubilization properties. The PGD hydrogels were prepared by crosslinking using ethylene glycol diglycidylether (EGDGE). The concentrations of EGDGE and PGDs were varied. The hydrogels were swellable in ethanol for loading paclitaxel (PTX). The amount of PTX in the hydrogels increased with the swelling ratio, which is proportional to EGDGE/OH ratio, meaning that heterogeneous crosslinking of PGD made high dense region of PGD molecules in the matrix. The hydrogels remained transparent after loading PTX and standing in water for one day, indicating that PTX was dispersed in the hydrogels without any crystallization in water. The results of FTIR imaging of the PTX-loaded PGD hydrogels revealed good dispersion of PTX in the hydrogel matrix. Sixty percent of the loaded PTX was released in a sink condition within 90 min, suggesting that the solubilized PTX would be useful for controlled release without any precipitation. Polyglycerol dendrimer hydrogels are expected to be applicable for rapid release of poorly water-soluble drugs, e.g., for oral administration.

Objective The objective of this study is to prepare new dental resins with a long-lasting antimicrobial activity. Specifically, this study evaluates an approach for controlling infection in root canals using sealers containing polyhydroxyethyl methacrylate trimethylolpropane trimethacrylate (polyHEMA/TMPT) particles loaded with cetylpyridinium chloride (CPC). In addition, the physical properties of sealers containing CPC-loaded polyHEMA/TMPT particles (CLP) are determined. Methods PolyHEMA/TMPT particles with 10 (10%-CLP) and 25 wt.% CPC (25%-CLP) with different particle sizes were fabricated and incorporated in HEMA-based sealers. CPC-release profiles were evaluated over 14 days of immersion in water, followed by 14 days of storage and 14 days of water immersion. The antibacterial activity of these sealers against Enterococcus faecalis in dentinal tubules was assessed using a root-canal-infection model. Their sealing abilities were evaluated by fluid filtration and physical properties were tested according to the ISO 6876 standard. The long-term antibacterial activity of the cured sealer containing 25%-CLP (∼21 μm particle diameter) was re-assessed after 1 year of storage. Results After 28 days of immersion, 25%-CLP exhibited a higher and sustained CPC release unlike 10%-CLP. Residual bacteria in root dentinal tubules were eradicated by obturation with 25%-CLP-containing sealers. The incorporation of 25%-CLP (∼21 μm) had no adverse effects on the sealing ability and physical properties of the sealer and resulted in long-term antibacterial activity. Significance The incorporation of CPC-loaded particles in HEMA resins yielded endodontic sealers with long-term bactericidal activity against E. faecalis in root canals. These sealers can potentially be used to prevent recurrent apical periodontitis.

This study focuses on dendritic glycerols and investigates the construction of biocompatible surfaces by understanding how differences in the branching of these molecules change the interactions with the biological components. The two molecules, polyglycerol dendrimer (PGD), which has a completely branched structure, and hyperbranched polyglycerol (HPG), which has an incompletely branched structure, are compared and the differences in branching are evaluated. It is shown that PGD has a little bit more intermediate water than HPG, which reflects the differences in the branching. The effect of surface state on the adsorption of the plasma proteins, human serum albumin (HSA), fibrinogen (Fib), and fibronectin (FN), is discussed by modifying a glass surface using these molecules with different hydration states. The adsorption of HSA decreases to several percent for HPG and 10% for PGD compared to unmodified substrate. Although the adsorption of Fib decreases to 5% for HPG, an increase to 150% is observed for PGD. Since this specific Fib adsorption observed only onto PGD is suppressed in the cases of a mixed solution of HSA and Fib or sequentially using HSA solution and then Fib solution, it is thought that the Vroman effect is suppressed on the PGD-modified surface. Furthermore, when AFM measurements are performed in PBS to understand the surface roughness, PGD is found to be more highly non-uniform. Because of this, the nanometer scale roughness that is significantly observed only on the PGD-modified surface is thought to have an effect on the characteristic adsorption properties of Fib. Thus, although both PGD and HPG with different branching have intermediate water, the proportion differs between PGD and HPG. Therefore, it is found that differences occur in the plasma protein adsorption mechanisms depending on the coordinates and density of hydroxyl groups within the molecules.

PEGylated liposomes have been used as carriers for delivery of anticancer drugs like doxorubicin (DOX) because of their bioinert nature. However, repeated administration of the PEGylated liposomes ...

Slide‐ring hydrogels using polyrotaxanes have been developed as highly tough soft materials. However, they have never been used as biomaterials because of the lack of biocompatibility. Meanwhile, self‐healing hydrogels are expected to improve fatigue resistance and extend the period of use. However, owing to the lack of high mechanical strength, they are limited in their use as biomaterials. Here we first developed a biocompatible self‐healing/slide‐ring hydrogel using glycol chitosan and a water‐soluble polyrotaxane. We obtained excellent mechanical toughness and biocompatibility to promote the proliferation of human umbilical vein endothelial cells (HUVECs) encapsulated in the hydrogel. Owing to the rapid self‐healing property, the cell‐encapsulating gels adjusted arbitrarily, maintaining good cell proliferation function. Therefore, slide‐ring hydrogels enable the use of biomaterials for soft‐tissue engineering.

We focused on introducing inclusion capability of β-cyclodextrin (β-CD) in an aqueous two-phase system (ATPS). A phase separation between two aqueous solutions of poly(ethylene glycol) (PEG) and de...

Amphiphilic copolymers consisting of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and hydrophobic monomers are known as biomaterials for the administration of poorly water-soluble drugs such as paclitaxel (PTX). However, the hydrophobic monomers to be copolymerized with MPC have not been optimized for PTX solubilization and its dosage forms. Here, we show the enhanced PTX solubility by only an MPC-based amphiphilic copolymer using a polyhedral oligomeric silsesquioxane (POSS) methacrylate (MA) bearing an ethyl (C2H5) group as a vertex group. MPC was copolymerized with POSS methacrylates bearing different vertex groups of ethyl (C2H5), hexyl (C6H13), and octyl (C8H17) via radical polymerization. We found that the strong interaction between C2H5-POSS and PTX contributed to the slow release of PTX without any burst release. The C2H5-POSS-MA MPC copolymer was internalized into the cultured HeLa cells, which was confirmed by using a fluorescein-4-isothiocyanate (FITC)-labeled PTX, and the PTX-dissolved copolymer induced cell death. We anticipate that the C2H5-POSS-MA MPC copolymer is a good solubilizer bearing a controlled release function for PTX.

Background: Ultrasound (US) is mostly used for diagnostic purpose but could be used for cancer treatments with a US intensity or frequency fitted to such a purpose. Prostate cancer (PC) has the highest prevalence in the urological field, but indications for immune checkpoint inhibitors (ICIs) for PC are limited to very few cases. In this study, we compared the antitumor effect of US irradiation alone with the combined use of US and ICIs in vitro and in vivo. Methods: PC cell line TRAMP-C2 cells were used in our experiments. TRAMP-C2 cells were irradiated with US with pulse repeated frequencies (PRF) of 1, 10, and 100 Hz. Cell proliferation was evaluated by MTS assay and apoptotic cells were analyzed using flow cytometry. To verify the antitumor effect of US irradiation on PC in vivo, we conducted animal experiments using mice. TRAMP-C2-bearing mice were irradiated with US with PRF of 10 and 100 Hz. Three weeks after the start of US irradiation, anti-PD-1 antibody was administered to the mice. Finally, mice were sacrificed and tumors were collected. Immunohistochemical (IHC) analyses were assessed for cleaved caspase-3 and CD3 in tumor cell extracts. Results: Cell proliferation assays showed that 1 and 10 Hz US significantly inhibited cell survival (p < 0.0001). In addition, US irradiation induced apoptosis at 1, 10, and 100 Hz (p = 0.0129, p = 0.0150, and p = 0.0017, respectively). In animal experiments, a significant tumor growth inhibitory effect was observed at 10 and 100 Hz, and 100 Hz + ICIs (p < 0.05, respectively). Hematoxylin–eosin (H–E) staining showed a significant increase in the necrotic area of the tumor at 100 Hz and 100 Hz + ICIs (p < 0.05, respectively). In addition, under IHC staining the expression level of cleaved caspase-3 and the number of CD3-positive cells increased at 100 Hz (p < 0.05, respectively). Conclusion: US irradiation induced apoptosis in cells and reduced cell viability. In vivo tumor growth was suppressed by combined treatment with US irradiation and ICIs. Further research on immune system activation will lead to less invasive and more efficient treatments for PC.

Dendrimer‐based supramolecular hydrogels have gained attention in biomedical fields. While biocompatible dendrimers were used to prepare hydrogels via physical and/or chemical crosslinking, smart functions such as pH and molecular control remain undeveloped. Here, we present polyglycerol dendrimer‐based supramolecular hydrogel formation induced by a specific interaction between the polyglycerol dendrimer and an amino group of glycol chitosan. Gelation was achieved by mixing the two aqueous solutions. Hydrogel formation was controlled by varying the polyglycerol dendrimer generation. The hydrogel showed pH‐dependent swelling; strongly acidic conditions induced degradation via dissociation of the specific interaction. It also showed unique l ‐arginine‐responsive degradation capability due to competitive exchange of the amino groups of glycol chitosan and l ‐arginine. These polyglycerol dendrimer‐based supramolecular characteristics allow multimodal application in smart biomaterials.

Synthetic receptors selective for target peptides or proteins have received attention because of their potential applications in the separation of biomolecules and biomedical diagnostics. Herein, a [2]rotaxane-based functional monomer containing monocarboxylated α-cyclodextrin (α-CD) was synthesized, and its crosslinked polymers were evaluated to determine their binding ability to a model peptide, angiotensin III (Arg-Val-Tyr-Ile-His-Pro-Phe), containing an arginine (Arg) residue. The binding ability of the resulting polymers toward angiotensin III, angiotensin IV (Val-Tyr-Ile-His-Pro-Phe), and FMRF-amide (Phe-Met-Arg-Phe) was examined by the batch-binding assay and compared with that of control polymers, in which maleic acid-introduced α-CD was chemically crosslinked. The results suggest that the [2]rotaxane-based functional monomer in the crosslinked polymer contributes to the high affinity toward angiotensin III. The α-CD motion and rotation within the [2]rotaxane-based crosslinked polymer may be applicable for designing molecular recognition materials.

High concentrations of &gamma, tocopherol (&gamma, TCP) tend to show antioxidant, anti-inflammatory, and anticancer effects. In this study, we prepared polymer micelles under acidic conditions with a controlled release of &gamma, TCP due to the decomposition of pendant acetal bonds. First, a precursor diblock copolymer composed of poly(ethylene glycol) (PEG) and acrylic acid (AA) was prepared. This was followed by the synthesis of an amphiphilic diblock copolymer (PEG54-P(AA/VE6/&gamma, TCP29)140), incorporated into hydrophobic &gamma, TCP pendant groups attached to the main chain through an acetal bond. The prepared PEG54-P(AA/VE6/&gamma, TCP29)140 was further dispersed in water to form polymer micelles composed of hydrophobic cores that were generated from a hydrophobic block containing &gamma, TCPs and hydrophilic shells on the surface. Under acidic conditions, &gamma, TCP was then released from the core of the polymer micelles due to the decomposition of the pendant acetal bonds. In addition, polymer micelles swelled under acidic conditions due to hydration of the core.

A hyperbranched polyglycerol-modified β-cyclodextrin (HPG-βCD) was examined as a solubilization agent of α-tocopherol (vitamin E). The HPG-βCD was prepared by anion polymerization of glycidol in the presence of β-CD. The HPG-βCD increased the solubility of α-tocopherol as compared with hydroxypropyl (HP)-βCD and HPG. Complexation efficacy (i.e., [complex]/[free host]) for HPG-βCD was 84 and 7 times higher than for HP-βCD and HPG, respectively. A 2D ROESY NMR data clearly indicate that α-tocopherol was encapsulated to βCD cavity of HPG-βCD with the intermolecular interaction with outer HPG moiety. These results suggest the solubilization enhancement was due to both inclusion complexation between βCD and α-tocopherol and hydrotropic solubilization by branched molecules of HPG. Therefore, the HPG-βCD is a good candidate as a solubilization agent of aliphatic compounds like vitamin E.

We investigated the nonspecific adsorption of proteins towards three hydrophilic crosslinked-polymeric thin layers prepared by surface-initiated atom transfer radical polymerization using N,N′-methylenebisacrylamide, 2-(methacryloyloxy)ethyl-[N-(2-methacryloyloxy)ethyl]phosphorylcholine (MMPC), or 6,6′-diacryloyl-trehalose crosslinkers. Protein binding experiments were performed by surface plasmon resonance with six proteins of different pI values including α-lactalbumin, bovine serum albumin (BSA), myoglobin, ribonuclease A, cytochrome C, and lysozyme in buffer solution at pH 7.4. All of the obtained crosslinked-polymeric thin layers showed low nonspecific adsorption of negatively charged proteins at pH 7.4 such as α-lactalbumin, BSA, and myoglobin. Nonspecific adsorption of positively charged proteins including ribonuclease A, cytochrome C, and lysozyme was the lowest for poly(MMPC). These results suggest poly(MMPC) can effectively reduce nonspecific adsorption of a wide range of proteins that are negatively or positively charged at pH 7.4. MMPC is a promising crosslinker for a wide range of polymeric materials requiring low nonspecific protein binding.

Enzymatic degradation of poly(e-caprolactone) (PCL) thin films was analyzed by reflectometric interference spectroscopy (RIfS)-based sensing system, and validated by attenuated total reflection infrared spectroscopy (ATR-IR) imaging. The degradation of the PCL thin film spin-coated on the silicon substrate on which 65-nm silicon nitride layer was deposited as an interference layer was easily monitored by shifting the peak bottom of reflectance spectra (Δλ) that is known to be proportional to the thickness of thin films. The Δλ values decreased with increasing the concentration of lipase from Pseudomonas cepacia, and the obtained sensorgrams were applied for kinetic analysis using a curve fitting software. ATR-IR spectra and imaging analysis on the surface of the PCL film revealed that carbonyl groups on the surface decreased with time, resulting from proceeding with the enzymatic hydrolysis, and importantly, extinction of the carbonyl group was declined with proportional to the decrease in the film thickness measured by the RIfS system. Consequently, the present RIfS-based label-free monitoring system can provide a simple and reliable way for evaluating biodegradability on synthetic materials. Statement of Significance A RIfS-based sensing system in combination with ATR-IR measurements can be an analytical method for evaluation of biodegradability of polymeric thin films. This study demonstrates the utility of the RIfS-based sensing approach for analyzing the lipase-catalyzed degradation of PCL. Despite the RIfS is known as an inexpensive label-free detection method for biological interaction, the RIfS applications as monitoring methods for enzymatic degradation of biodegradable polymers had not been systematically explored. This study additionally demonstrated the capability of combined analysis of the biodegradation with ATR-IR spectra/imaging and RIfS measurements, which could be broadly applied towards evaluating biodegradability of various biodegradable polymers in environmental protection research.

Herein we present a tuned cell attachment on self-healable double network hydrogel bearing dynamic covalent bonds and hydrogen bonds. Agar formed first network, while glycol chitosan and oxidized carboxylmethyl cellulose formed second network in the resultant double network hydrogel. Because of the simple one-pot preparation, the hydrogel can be injected by using syringes. The moduli of the hydrogel were improved compared to that of the parent single-network. The hydrogel exhibited self-healing ability without need for heating or cut surface treatment. The incorporation of agar in the double network induced the enhanced protein adsorption, and the following cell attachments were governed by the adsorbed protein states. Therefore, the double network hydrogel holds great potential for applications in various biomedical applications.

Enzyme application has gained importance over the past decade in bioprocess, biomedical, and pharmaceutical fields. We found that polyglycerol dendrimers (PGDs), which are biocompatible molecules, can recover alcohol dehydrogenase (ADH) from aqueous solution under elevated temperature. A low concentration of PGD (5 wt.%) is sufficient for the recovery of high enzymatic activity, although a high concentration (25–75 wt.%) of glycerol is generally required to stabilize ADH. The enzymatic activity of ADH in suspension with PGDs is over 60% but it is only 10% in that with glycerol. The results of osmolarity and spin-lattice relaxation time (T1) of water measurements in the presence of PGDs suggest that increased amounts of bound water to PGD molecules trigger aggregation along with the direct interaction with ADH. PGDs therefore represent good potential additives for direct recovery of enzymes from aqueous solutions.

An amphiphilic polyglycerol dendron (PGD) conjugated porphyrin (PGP) bearing a polymerizable group was successfully synthesized. The PGP was used as an effective surfactant in emulsion and microsuspension polymerization systems to prepare styrene and methacrylate polymer particles, and the use of PGP provided the simple polymer particles with fluorescence derived from the metalloporphyrin and high colloidal stability due to the PGD. Furthermore, based on confocal laser scanning microscopy, we observed that the particles spontaneously formed a core-shell morphology with the PGP localized in the shell region during the polymerization and demonstrated drug loading in the shell region using rhodamine B as a model drug. The results indicate that the use of the functional surfactant PGP led to the preparation of multifunctional polymer particles from simple monomer species, and the resulting particles possessed high colloidal stability, fluorescence, and drug loading capability.

A polyglycerol dendrimer (PGD), which is known as a biocompatible compound, was demonstrated as a host molecule for amino acids. PGD of generation 3 (PGD-G3) was found to interact with basic α-amino acids such as l-arginine (Arg) and l-lysine (Lys) in water. The results of isothermal titration calorimetry, 1H NMR, and 1H-1H NOESY NMR measurements revealed that two basic groups in α-amino acids were essential for encapsulation by PGD-G3. An increase in the pKa value of the amino acid side chains (Arg>Lys>His>Glu) increased the binding constant, thus suggesting that the basicity of α-amino acids is an important factor to interact with ether oxygen of PGD-G3. The results demonstrate the utility of PGD-G3 toward incorporation of α-amino acids, peptides, and basic proteins in water.

We demonstrated the synthesis of molecularly imprinted polymers (MIPs) with binding affinity toward a target protein, ribonuclease A (RNase) by atom transfer radical polymerization (ATRP) of acrylic acid, acrylamide, and N,N'-methylenebisacrylamide in the presence of RNase. The binding activity of the MIPs was evaluated by surface plasmon resonance (SPR) of the MIP thin layers prepared on the gold-coated sensor chips. The MIPs prepared by ATRP (MIP-ATRP) had a binding affinity toward RNase with larger binding amount compared to MIPs prepared by conventional free radical polymerization methods (MIP-RP). Moreover, protein selectivity was evaluated using reference proteins (cytochrome c, myoglobin, and α-lactalbumin) and was confirmed in MIP-ATRP of optimum film thickness determined experimentally to be 15-30 nm; however, protein selectivity was not achieved in all MIP-RP. We have shown that ATRP is powerful technique for preparing protein recognition materials by molecular imprinting.

A dynamic hydrogel formulated by mixing a glycol chitosan (GC) and an oxidized dextran (Odex) were studied for protein-controlled release in conjunction with the hydrogel fragmentation. A series of injectable dynamic hydrogels were derived from GC and Odex upon simple mixing without the addition of chemical crosslinking agents. The gelation readily took place at physiological pH and temperature. The influence of the concentration of GC and Odex on the gelation time, mechanical properties, water content, in vitro degradation were investigated. The Odex/GC hydrogels showed good self-healing ability under physiological conditions and kept the dynamic Schiff-base linkage at over 2 wt %. The release kinetics of a model protein (bovine serum albumin) was found to be controlled by changing the needle size upon injection, attributed to modulation of apparent size and shape of the fragmented hydrogels even in the self-healed state. Therefore, the GC-based injectable and dynamic hydrogels are expected to be a promising platform for protein delivery system and various biomedical applications.

We demonstrate a novel synthetic route for molecularly imprinted polymer (MIP) thin films using a bottom-up approach utilizing protein–ligand specific interactions. The ligand was anchored on a gold substrate and served to (i) orient the immobilized target protein for precise formation of homogeneous binding cavities and (ii) act as a binding site with high affinity and selectivity on the MIP thin films after release of the immobilized protein. The MIP thin films were synthesized by controlled/living radical polymerization (CLRP), which allowed for precise control of the film thickness to optimize binding performance. A mixed self-assembled monolayer comprising anchored maleimide groups and bromoisobutyryl groups was constructed on a gold substrate: the former oriented the immobilization of the target protein and the latter initiated CLRP. The chosen model target protein and ligand were glutathione-s-transferase-π (GST-π) and glutathione (GSH), a protein-specific ligand to GST-π. The obtained MIP thin films of precisely controlled film thickness exhibited high affinity toward the target protein compared to non-imprinted polymer (NIP) thin films. Protein binding selectivity was investigated using a selectivity parameter (α) calculated by surface plasmon resonance response with reference proteins, human serum albumin (HSA) and fibrinogen (FIB). The results indicated that the MIP film thickness affects the protein binding selectivity: a polymer thickness of approximately 15 nm gave more selective protein binding (selectivity parameter for α(HSA) = 0.09 and for α(FIB) = 0.30). Furthermore, we clarified that a more hydrophilic polymer matrix in the presence of NaCl gave more selective binding of GST-π. Our findings show that this bottom-up synthetic route has potential for facilitating the fabrication of highly specific MIPs as artificial protein recognition materials.

Design of polymeric micelles, formed by self-assembly of amphiphilic block copolymers, is crucial for encapsulation of poorly soluble drugs, leading to the development of promising carrier systems. Herein, we synthesized amphiphilic diblock copolymers of 2-(methacryloyloxy)ethyl phosphorylcholine (MPC) and methacrylate R-polyhedral oligomeric silsesquioxanes (POSS) (vertex R-groups of POSS cage modified with ethyl (C2H5), hexayl (C6H13), octayl (C8H17) alkyl chain) via RAFT polymerization technique. Polymeric micelle was formed in aqueous environment, and the absolute size was calculated to be around 26–43 nm. The increased alkyl chain length of the R-groups of POSS led to loosely packed association of the micelles. The polymeric micelles encapsulated the hydrophobic model drugs (paclitaxel and α-tocopherol), and the encapsulation efficiency was strongly dependent on the structure of drug molecules. The drug-loaded micelles were stable for 5 days at 25 °C. The release % of both the drugs from the micelles was at a negligible level or below 20%, suggesting the strong interaction between the R-POSS moieties and the drug molecules. Cellular uptake of the micelles by HeLa cells was quantitatively analyzed using a FITC-labeled paclitaxel (FITC-PTX). All the micelles were internalized by the cell after 2 h, and cellular uptake of PTX-loaded micelle composed of the C6H13–POSS copolymer reached the highest level, suggesting that the alkyl chain length is one of the tunable factors for the cellular uptake. These diblock copolymers have great potential as a hydrophobic drug carrier molecule and its delivery to specific sites.

Protein-imprinted polymers, capable of specific transduction of protein binding events into fluorescent signal change, were designed and synthesized by using dansyl ethylenediamine-conjugated O-acryloyl L-hydroxyproline (Hyp-En-Dans). Human serum albumin (HSA) was used as a model target protein and HSA-imprinted polymers (HSA-IP) were prepared on glass substrates. Specific fluorescence change was observed for HSA binding on the imprinted polymer thin film, whereas a weaker response was observed for other proteins, including bovine serum albumin, chymotrypsin, lysozyme, and avidin. The binding specificity was found to derive from the rigid structure of the hydrogen-bondable pyrrolidine moiety. Compared with SPR measurements, the non-specific binding caused by the polymer matrix and/or randomly located fluorescent monomer residues that did not compose specific binding sites did not contribute to the observed fluorescence change. These results revealed that the proposed protein-imprinting technique using Hyp-En-Dans could provide a highly selective protein-sensing platform, in which only specific binding events would be detected by fluorescent measurements.

Simple method to immobilize antibody in organic/inorganic hybrid thin films, prepared easily by using liquid phase deposition (LPD), was proposed to enhance the sensitivity, reproducibility and stability of immunosensing chips. The LPD method could embed a monoclonal antibody of C-reactive protein (Anti-CRP), which is mixed with poly(l-lysine) (PL) as an organic binder, on/in titanium oxide thin layer deposited onto a surface plasmon resonance (SPR) sensing chip (F(Anti-CRP-PL)), allowing simple immobilization of anti-CRP capable of CRP detection. As a control, anti-CRP was non-covalently immobilized after preparing the titanium oxide layer containing PL (SIF(Anti-CRP-PL)). Binding experiments of CRP on the prepared sensor chips were performed by SPR measurements. The CRP binding capacity of anti-CRP on F(Anti-CRP-PL) was 54% greater than that of anti-CRP on SIF (Anti-CRP-PL), suggesting that the immobilization method could retain good antigen-binding activity of anti-CRP. Reproducibility of the antigen-antibody interaction was estimated by SPR using 10mM HCl as the regeneration regent. CRP was repeatedly detected, and the detection limit was calculated to be 19.9ngmL(-1) (CV: 8.9%). By using this method, antibodies could be simply immobilized to various kinds of sensing chips for the development of immunosensing systems.

We have prepared a hydrophilic molecularly imprinted polymer (MIP) for the hydrophobic compound bisphenol A (BPA) in aqueous solution using 3-acrylamido-N,N,N-trimethylpropan-1-aminium chloride (AMTC) as the functional monomer. Under redox-polymerization conditions, BPA forms an ion-pair with AMTC, which was confirmed by 1H-NMR titration. The imprinting effect in aqueous solution was evaluated by comparison of this material with the corresponding non-imprinted polymer (NIP) and with a control polymer (CP) bearing no AMTC. The MIP showed the highest activity among the three polymers, and the imprinting factors as calculated from the amount of BPA bound to the MIP divided by the amounts bound to NIP and CP, respectively, are 1.8 and 6.0. The MIP was selective for BPA in aqueous solution, while structurally related compounds are not recognized. Such a selectivity for a hydrophobic compound is rarely observed in aqueous medium because non-specific binding of BPA inevitably leads to hydrophobic interaction.