Injectable hydrogels based on biopolymers for the treatment of ocular diseases.

Injectable hydrogels based on biopolymers, fabricated utilizing diverse chemical and physical methodologies, exhibit exceptional physical, chemical, and biological properties. They have multifaceted applications encompassing wound healing, tissue regeneration, and across diverse scientific realms. This review critically evaluates their largely uncharted potential in ophthalmology, elucidating their diverse applications across an array of ocular diseases. These conditions include glaucoma, cataracts, corneal disorders (spanning from age-related degeneration to trauma, infections, and underlying chronic illnesses), retina-associated ailments (such as diabetic retinopathy, retinitis pigmentosa, and age-related macular degeneration (AMD)), eyelid abnormalities, and uveal melanoma (UM). This study provides a thorough analysis of applications of injectable hydrogels based on biopolymers across these ocular disorders. Injectable hydrogels based on biopolymers can be customized to have specific physical, chemical, and biological properties that make them suitable as drug delivery vehicles, tissue scaffolds, and sealants in the eye. For example, they can be engineered to have optimum viscosity to be injected intravitreally and sustain drug release to treat retinal diseases. Their porous structure and biocompatibility promote cellular infiltration to regenerate diseased corneal tissue. By accentuating their indispensable role in ocular disease treatment, this review strives to present innovative and targeted approaches in this domain, thereby advancing ocular therapeutics.

Prognostic role of the controlling nutritional status (CONUT) score in patients with biliary tract cancer: a meta-analysis.

BACKGROUND: Previous reports have not reached consistent results regarding the prognostic significance of the controlling nutritional status (CONUT) score in biliary tract cancer (BTC). Therefore, the present meta-analysis was conducted to investigate the precise role of the CONUT score in predicting the prognosis of BTC. METHODS: Electronic platforms including Web of Science, PubMed, Cochrane Library, and Embase were comprehensively searched up to May 2, 2023. We also determined combined hazard ratios (HRs) and 95% confidence intervals (CIs) to estimate the role of the CONUT score in predicting the prognosis of patients with BTC. RESULTS: Ten studies involving 1,441 patients were included in the present study. Nine studies treated patients with surgical resection, and one study used percutaneous transhepatic biliary stenting (PTBS) plus 125I seed intracavitary irradiation. Based on the combined data, a higher CONUT score significantly predicted dismal overall survival (OS) (HR = 1.94, 95%CI = 1.41-2.66, p < 0.001), inferior recurrence-free survival (RFS) (HR = 1.79, 95%CI = 1.48-2.17, p < 0.001) in BTC, and low differentiation (OR = 1.57, 95%CI = 1.15-2.14, p = 0.004). Nonetheless, the CONUT score was not related to sex, lymph node metastasis, microvascular invasion, perineural invasion, distant metastasis, TNM stage, or tumor number in patients with BTC. CONCLUSION: Higher CONUT scores significantly predicted worse OS and RFS in patients with BTC. Moreover, BTC patients with high CONUT scores tended to have poor tumor differentiation. The CONUT score could help clinicians stratify high-risk patients with BTC and devise individualized treatment plans.

As far as we know, this study is the first to analyze whether pretreatment CONUT is significant for predicting the prognosis of BTC.A high CONUT significantly predicted worse OS and RFS in BTC patients.CONUT could help clinicians stratify high-risk BTC patients and devise individualized treatment plans.

Modulating the local coordination environment of cobalt single-atomic nanozymes for enhanced catalytic therapy against bacteria.

Single-atomic nanozymes (SANZs) characterized by atomically dispersed single metal atoms have recently contributed to breakthroughs in biomedicine due to their satisfactory catalytic activity and superior selectivity compared to their nanoscale counterparts. The catalytic performance of SANZs can be improved by modulating their coordination structure. Therefore, adjusting the coordination number of the metal atoms in the active center is a potential method for enhancing the catalytic therapy effect. In this study, we synthesized various atomically dispersed Co nanozymes with different nitrogen coordination numbers for peroxidase (POD)-mimicking single-atomic catalytic antibacterial therapy. Among the polyvinylpyrrolidone modified single-atomic Co nanozymes with nitrogen coordination numbers of 3 (PSACNZs-N3-C) and 4 (PSACNZs-N4-C), single-atomic Co nanozymes with a coordination number of 2 (PSACNZs-N2-C) had the highest POD-like catalytic activity. Kinetic assays and Density functional theory (DFT) calculations indicated that reducing the coordination number can lower the reaction energy barrier of single-atomic Co nanozymes (PSACNZs-Nx-C), thereby increasing their catalytic performance. In vitro and in vivo antibacterial assays demonstrated that PSACNZs-N2-C had the best antibacterial effect. This study provides proof of concept for enhancing single-atomic catalytic therapy by regulating the coordination number for various biomedical applications, such as tumor therapy and wound disinfection. STATEMENT OF SIGNIFICANCE: The use of nanozymes that contain single-atomic catalytic sites has been shown to effectively promote the healing of bacteria-infected wounds by exhibiting peroxidase-like activity. The homogeneous coordination environment of the catalytic site has been associated with high antimicrobial activity, which provides insight into designing new active structures and understanding their mechanisms of action. In this study, we designed a series of cobalt single-atomic nanozymes (PSACNZs-Nx-C) with different coordination environments by shearing the Co-N bond and modifying polyvinylpyrrolidone (PVP). The synthesized PSACNZs-Nx-C demonstrated enhanced antibacterial activity against both Gram-positive and Gram-negative bacterial strains, and showed good biocompatibility in both in vivo and in vitro experiments.

Research on the influence of physical exercise on insomnia and suicide of college students.

OBJECTIVE: To investigate the influence of physical exercise on insomnia and suicide among college students. METHODS: A total of 8095 college students in Changsha were selected by cluster sampling and investigated with self-made general condition scale, physical activity scale and Athens insomnia scale. The multivariate Logistic regression analysis was used to explore the risk factors of insomnia and suicide among college students. RESULTS: A total of 1859 college students (22.9%) were found to have insomnia behaviors. Of these, 763 (41%) and 1096 (59%) undergraduates had suicidal thoughts. The results of multivariate Logistic regression analysis showed that physical disease history, smoking, alcohol consumption, suicidal ideation, suicidal attempt and physical activity (P < 0.05) were all the independent influencing factors for insomnia among college students. Gender, physical disease history, suicide plan, suicide attempt, and physical activity (P < 0.05) were the independent influencing factors of suicidal ideation in insomnia college students. CONCLUSION: The detection rate of suicidal ideation is high in insomnia college students. Physical disease history, suicide attempt and physical activity may be the related factors of suicidal ideation. Physical activity was the influencing factor of college students' insomnia behavior, and heavy exercise was the independent protection factor of college students' insomnia behavior. At the same time, heavy exercise was a protective factor for insomnia college students with suicidal ideation.

The effect of a brief, unplanned treatment delay on neovascular age-related macular degeneration patients: a retrospective cohort study.

Non-compliance to intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapy can result in increased disease activity in neovascular age-related macular degeneration (nAMD). Our study aims to determine effects of unplanned delay in anti-VEGF injection treatment for nAMD. This retrospective observational study included patients with delays in receiving intravitreal injections for nAMD treatment from March to May 2020 by at least 21 days. Baseline demographic and clinical characteristics, visual acuity (VA), central macular thickness (CMT) measured on optical coherence tomography (OCT), and duration of delayed treatment were analyzed for 3 time points, the pre-delay visit (v1) and post-delay visits (v2 and v3). Data were compared to age-matched controls treated for nAMD in 2019 without delay. Demographic characteristics were compared using two-sample t-tests for continuous variables and Pearson's chi-square tests for categorical variables. For the two primary outcomes of interest, VA and CMT, means and standard deviations were reported for each combination of group and time. Each outcome was modeled using a linear mixed model with the group, time and group-time interaction as fixed effects. A total of 69 patients (99 eyes) in the treatment delay group and 44 patients (69 eyes) in the control group were identified. Statistically significant differences between control and delayed groups were detected for VA (difference in mean logMAR = 0.16; 95% CI 0.06, 0.27; p = 0.002) and CMT (difference in mean CMT = 29; 95% CI 12, 47; p = 0.001) at v2. No differences were detected for v1 and v3 time points for both outcomes. An unplanned delay in intravitreal injection treatment for nAMD resulted in an increase in CMT and worsening of VA compared to controls observed at v2. At v3, CMT and VA recovered to near v1 levels. This study demonstrates that a one-time, brief interruption in treatment for nAMD results in reversible, temporary worsening.

Drug-loaded oleic-acid grafted mesoporous silica nanoparticles conjugated with α-lactalbumin resembling BAMLET-like anticancer agent with improved biocompatibility and therapeutic efficacy.

Despite its prominent therapeutic efficacy, chemotherapy has raised serious concerns due to the severe adverse effects and multidrug resistance evoked, which propels the search for safe and green therapeutic agents. BAMLET (bovine α-lactalbumin made lethal against tumor cell) is a well-known protein-based anticancer agent of selective tumoricidal activity. Here, we prepared oleic acid-modified mesoporous silica nanoparticles (OA-MSNs) conjugated with bovine α-lactalbumin, a lipoprotein complex resembling BAMLET formed on the surface of MSNs (MSN-BAMLET) to load the anticancer drug of docetaxel (DTX). Compared to that of OA-MSNs/DTX, the obtained MSN-BAMLET/DTX with a sustained and pH-responsive drug release behaviors exhibited good biocompatibility and enhanced cytotoxic effect against cancer cells. Moreover, the presence of lipoprotein complex in MSN-BAMLET contributed to the improved dispersion of the composite in solution and the inhibitory effect on the migration of cancer cells. Furthermore, the adsorption profiles of protein corona on the obtained nanoparticles were analyzed. It was found that the marked low amount and abundance of plasma proteins were adsorbed on the α-lactalbumin coated siliceous composite demonstrated its long circulation property. Finally, in vivo study showed that MSN-BAMLET/DTX contributed to the effective cancer ablation and the prolonged survival. Therefore, the constructed MSN-BAMLET of the mesoregular structure and peculiar tumoricidal effect provides a manipulable nanoplatform as drug nanocarrier for therapeutic applications.

Complications With Surgical Treatment of Pediatric Supracondylar Humerus Fractures: Does Surgeon Training Matter?

INTRODUCTION: National trends reveal increased transfers to referral hospitals for surgical management of pediatric supracondylar humerus (SCH) fractures. This is partly because of the belief that pediatric orthopaedic surgeons (POs) deliver improved outcomes compared with nonpediatric orthopaedic surgeons (NPOs). We compared early outcomes of surgically treated SCH fractures between POs and NPOs at a single center where both groups manage these fractures. METHODS: Patients ages 3 to 10 undergoing surgery for SCH fractures from 2014 to 2020 were included. Patient demographics and perioperative details were recorded. Radiographs at surgery and short-term follow-up assessed reduction. Primary outcomes were major loss of reduction (MLOR) and iatrogenic nerve injury (INI). Complications were compared between PO-treated and NPO-treated cohorts. RESULTS: Three hundred and eleven fractures were reviewed. POs managed 132 cases, and NPOs managed 179 cases. Rate of MLOR was 1.5% among POs and 2.2% among NPOs (P=1). Rate of INI was 0% among POs and 3.4% among NPOs (P=0.041). All nerve palsies resolved postoperatively by mean 13.1 weeks. Rates of reoperation, infection, readmission, and open reduction were not significantly different. Operative times were decreased among POs (38.1 vs. 44.6 min; P=0.030). Pin constructs were graded as higher quality in the PO group, with a higher mean pin spread ratio (P=0.029), lower rate of "C" constructs (only 1 "column" engaged; P=0.010) and less frequent crossed-pin technique (P<0.001). Multivariate analysis revealed minimal positive associations only for operative time with MLOR (odds ratio=1.021; P=0.005) and INI (odds ratio=1.048; P=0.009). CONCLUSIONS: Postsurgical outcomes between POs and NPOs were similar. Rates of MLOR were not different between groups, despite differences in pin constructs. The NPO group experienced a marginally higher rate of INI, though all injuries resolved. Pediatric subspecialty training is not a prerequisite for successfully treating SCH fractures, and overall value of orthopaedic care may be improved by decreasing transfers for these common injuries. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

Nanobody-based immunosensing methods for safeguarding public health.

Immunosensing methods are biosensing techniques based on specific recognition of an antigen-antibody immunocomplex, which have become commonly used in safeguarding public health. Taking advantage of antibody-related biotechnological advances, the utilization of an antigen-binding fragment of a heavy-chain-only antibody termed as 'nanobody' holds significant biomedical potential. Compared with the conventional full-length antibody, a single-domain nanobody retaining cognate antigen specificity possesses remarkable physicochemical stability and structural adaptability, which enables a flexible and efficient molecular design of the immunosensing strategy. This minireview aims to summarize the recent progress in immunosensing methods using nanobody targeting tumor markers, environmental pollutants, and foodborne microbes.

Toxicity-attenuated mesoporous silica Schiff-base bonded anticancer drug complexes for chemotherapy of drug resistant cancer.

Multidrug resistance (MDR), evoked by improper chemotherapeutic practices, poses a serious threat to public health, which leads to increased medical burdens and weakened curative effects. Taking advantage of the enhanced pharmaceutical effect of Schiff base compounds, an aldehyde-modified mesoporous silica SBA-15 (CHO-SBA-15)-bonded anticancer drug combined with doxorubicin hydrochloride (DOX) was synthesized via a Schiff base reaction. Due to the acid-sensitive imine bonds formed between CHO-SBA-15 and DOX, the as-prepared nanocomposites exhibited pH-responsive drug releasing behaviours, resulting in a more enhanced cytotoxic effect on DOX-resistant tumour cells than that of free drugs. Notably, the in vivo studies indicated that mice treated with CHO-SBA-15/DOX composites evidently showed more attenuated systemic toxicity than the free drug molecules. The siliceous mesopore Schiff base-bonded anticancer drug nanocomposite, with minimal chemical modifications, provides a simplified yet efficient therapeutic nanoplatform to deal with drug-resistant cancer.

Comparison of Cytotoxicity Evaluation of Anticancer Drugs between Real-Time Cell Analysis and CCK-8 Method.

Critical cytotoxicity evaluation of pharmaceuticals is necessary for the clinical practice of chemotherapy. To quantitatively evaluate cell viability, currently there are two main types of sensitive methods including real-time cell analysis (RTCA) and CCK-8 assay, in which RTCA records electrochemical signal changes around an incubated cell, whereas CCK-8 is based on the colorimetric method. Despite the different detection principles adopted for the cytotoxicity assessment, the comparison of the two methods in terms of the application scope is lacking. In this study, comparison studies were conducted between the RTCA and CCK-8 assays using anticancer drugs including doxorubicin hydrochloride, curcumin, irinotecan (CPT-11), taxol, and oxaliplatin, which are classified into two groups of drug molecules in the absence and presence of additives. The cytotoxicity evaluation of these drugs on cancer cells revealed that the physicochemical properties of drug formulations such as optical and electrochemical properties are closely linked with the readout of cytotoxic methods. The experimental results suggested that the preselection of cytotoxic assay is critical for the quantitative measurement of cytotoxicity of anticancer drugs, which is of clinical importance for their therapeutic usage.

Real-time cell analysis of the cytotoxicity of a pH-responsive drug-delivery matrix based on mesoporous silica materials functionalized with ferrocenecarboxylic acid.

During the past decade, accumulating studies have been conducted on the mesoporous silica materials as the matrix of controlled drug-delivery, in which the complicated post-synthesis procedures are often involved with the molecular design to achieve the efficacy. In this study, a simplified drug delivery system of anti-cancer drug of doxorubicin (DOX) based on mesoporous SBA-15 functionalized with ferrocenecarboxylic acid (FCA) was constructed. Through a combination of physicochemical characterizations, the presence of FCA that was anchored inside the pore wall of amine groups grafted SBA-15 exhibits electron-accessible behavior without affecting the intactness of composite material. The pH-responsive release of drug molecules was achieved through the conjugation of DOX with FCA in the interior channels of mesoporous composites, which also favors the more coverage of DOX. Furthermore, the real-time cell analysis was performed to monitor the release of DOX from the mesopores and resulting cytotoxicity of cancer cell of A549 was evaluated, which results in a calculated IC50 of 43.8 µg/ml (24 h). The constructed mesoporous FCA-SBA-15 composite material provides an integrated nanoplatform to exert controlled-delivery of anti-cancer drug molecules.

Regeneration of Arrayed Gold Microelectrodes Equipped for a Real-Time Cell Analyzer.

The label-free cell-based assay is advantageous for biochemical study because of it does not require the use of experimental animals. Due to its ability to provide more dynamic information about cells under physiological conditions than classical biochemical assays, this label-free real-time cell assay based on the electric impedance principle is attracting more attention during the past decade. However, its practical utilization may be limited due to the relatively expensive cost of measurement, in which costly consumable disposable gold microchips are used for the cell analyzer. In this protocol, we have developed a general strategy to regenerate arrayed gold microelectrodes equipped for a commercial label-free cell analyzer. The regeneration process includes trypsin digestion, rinsing with ethanol and water, and a spinning step. The proposed method has been tested and shown to be effective for the regeneration and repeated usage of commercial electronic plates at least three times, which will help researchers save on the high running cost of real-time cell assays.

Raspberry-Like Bismuth Oxychloride on Mesoporous Siliceous Support for Sensitive Electrochemical Stripping Analysis of Cadmium.

BiOCl-SiO2 KIT-6 composite materials with raspberry-like structures are facilely prepared under hydrothermal conditions. The mesoporous siliceous support of SiO2 KIT-6-incorporated BiOCl with enlarged yet refined surface morphology characterized by physiochemical methods exhibits an improved electrochemical performance. A sensitive electrochemical detection method of cadmium concentration using square wave anodic stripping voltammetry was developed based on BiOCl-SiO2 KIT-6 composite-modified glassy carbon electrodes, which displayed wide linear ranges of 0.5 to 10 µg/L and 10 to 300 µg/L and a detection limit of 65 ng/L. The sensitive, versatile and eco-friendly sensor was successfully applied for the determination of cadmium-spiked human blood samples.

A general method to regenerate arrayed gold microelectrodes for label-free cell assay.

We developed a method to regenerate arrayed gold microelectrodes equipped for a commercial label-free cell analyzer. The regeneration process includes efficient treatment of the gold surface with trypsin (0.25%, v/v) digestion, rinsing with ethanol and deionized water and spinning steps. The proposed method ensured complete regeneration and repeated usage of gold microchips up to 4 times for the real-time electric impedance measurement of anti-cancer drug cytotoxicity.

Magnetic sensing film based on Fe3O4@Au-GSH molecularly imprinted polymers for the electrochemical detection of estradiol.

A novel magnetic molecularly imprinted sensing film (MMISF) was fabricated for the determination of estradiol (E2) based on magnetic glassy carbon electrode (MGCE) and magnetic molecularly imprinted polymers (MMIPs). The MMIPs were synthesized by in situ polymerization of glutathione (GSH)-functionalized gold (Au)-coated Fe3O4 (Fe3O4@Au-GSH) nanocomposites and aniline. The MMISF was constructed with MMIPs via a kind of "soft modification" where MMIPs were assembled and immobilized on the surface of MGCE or removed from it by freely installing a magnet into MGCE or not. The E2-MMIPs were obtained by MMIPs recognizing E2 from sample, and the electrochemical detection was carried out after forming the "soft modification" sensing film by putting MGCE into the E2-MMIPs suspension liquid. Afterwards, the "soft modification" MMISF was peeled off from the electrode by removing the magnet from MGCE. The interface of the electrode could be quickly refreshed through simple treatment for the next detection. The structures and morphologies of Fe3O4@Au-GSH, MMIPs and MMISF were investigated by Fourier transform infrared spectrometer, ultraviolet and visible spectrophotometer, scanning electron microscope and atomic force microscope. In addition, the MMISF was successfully used for detecting E2 in milk powder with good sensitivity, selectivity, reproducibility and efficiency. The linear range of the MMISF for E2 was 0.025-10.0µmolL(-1) with the limit of detection of 2.76nmolL(-1) (S/N= 3).

Facile and controllable one-step fabrication of molecularly imprinted polymer membrane by magnetic field directed self-assembly for electrochemical sensing of glutathione.

Based on magnetic field directed self-assembly (MDSA) of the ternary Fe3O4@PANI/rGO nanocomposites, a facile and controllable molecularly imprinted electrochemical sensor (MIES) was fabricated through a one-step approach for detection of glutathione (GSH). The ternary Fe3O4@PANI/rGO nanocomposites were obtained by chemical oxidative polymerization and intercalation of Fe3O4@PANI into the graphene oxide layers via π-π stacking interaction, followed by reduction of graphene oxide in the presence of hydrazine hydrate. In molecular imprinting process, the pre-polymers, including GSH as template molecule, Fe3O4@PANI/rGO nanocomposites as functional monomers and pyrrole as both cross-linker and co-monomer, was assembled through N-H hydrogen bonds and the electrostatic interaction, and then was rapidly oriented onto the surface of MGCE under the magnetic field induction. Subsequently, the electrochemical GSH sensor was formed by electropolymerization. In this work, the ternary Fe3O4@PANI/rGO nanocomposites could not only provide available functionalized sites in the matrix to form hydrogen bond and electrostatic interaction with GSH, but also afford a promoting network for electron transfer. Moreover, the biomimetic sensing membrane could be controlled more conveniently and effectively by adjusting the magnetic field strength. The as-prepared controllable sensor showed good stability and reproducibility for the determination of GSH with the detection limit reaching 3 nmol L(-1) (S/N = 3). In addition, the highly sensitive and selective biomimetic sensor has been successfully used for the clinical determination of GSH in biological samples.

Combination of chemotherapy and photodynamic therapy using graphene oxide as drug delivery system.

Previous research indicated that graphene oxide (GO) can be used to deliver photosensitive anticancer drug, Hypocrellin A (HA), in photodynamic therapy (PDT). However, the anticancer activity of HA was obviously decreased after been loaded on GO. To solve this problem, a chemotherapy drug, 7-ethyl-10-hydroxycamptothecin (SN-38), was co-loaded on the HA loaded GO (HA/SN-38/GO) as a multimodal carrier for the synergistic combination of PDT and chemotherapy for cancer. In vitro results showed that the combination therapy exhibited a synergistic antiproliferative effect compared with PDT and chemotherapy alone. Therefore, HA/SN-38/GO delivery system has the potential to offer dual therapies for the synergistic combination of PDT and chemotherapy for the treatment of cancer.

Loss of heterozygosity (LOH) profiles--validated risk predictors for progression to oral cancer.

A major barrier to oral cancer prevention has been the lack of validated risk predictors for oral premalignant lesions (OPL). In 2000, we proposed a loss of heterozygosity (LOH) risk model in a retrospective study. This paper validated the previously reported LOH profiles as risk predictors and developed refined models via the largest longitudinal study to date of low-grade OPLs from a population-based patient group. Analysis involved a prospective cohort of 296 patients with primary mild/moderate oral dysplasia enrolled in the Oral Cancer Prediction Longitudinal Study. LOH status was determined in these OPLs. Patients were classified into high-risk or low-risk profiles to validate the 2000 model. Risk models were refined using recursive partitioning and Cox regression analyses. The prospective cohort validated that the high-risk lesions (3p and/or 9p LOH) had a 22.6-fold increase in risk (P = 0.002) compared with low-risk lesions (3p and 9p retention). Addition of another 2 markers (loci on 4q/17p) further improved the risk prediction, with five-year progression rates of 3.1%, 16.3%, and 63.1% for the low-, intermediate-, and high-risk lesions, respectively. Compared with the low-risk group, intermediate- and high-risk groups had 11.6-fold and 52.1-fold increase in risk (P < 0.001). LOH profiles as risk predictors in the refined model were validated in the retrospective cohort. Multicovariate analysis with clinical features showed LOH models to be the most significant predictors of progression. LOH profiles can reliably differentiate progression risk for OPLs. Potential uses include increasing surveillance for patients with elevated risk, improving target intervention for high-risk patients while sparing a large number of low-risk patients from needless screening and treatment.

Graphene oxide noncovalent photosensitizer and its anticancer activity in vitro.

Graphene oxide (GO) was investigated as a potential drug-delivery system due to its special properties and biocompatibility. Thus far, little has been done to use GO as a photosensitive drug-delivery system and to explore its anticancer activity in vitro in photodynamic therapy applications. Here, a novel GO-hypocrellin A (GO-HA) hybrid was prepared by a simple noncovalent method and its photodynamic activity was studied for the first time. The results showed that an efficient loading amount of HA on GO was as high as 1.0 mg mg(-1) and the stability of the hybrid was superior to that of the free hypocrellin A in aqueous solution. Furthermore, GO-HA can be excited by irradiation with light of appropriate wavelength to generate singlet oxygen, and in vitro experiments illustrated that GO-HA was efficiently taken up by tumor cells, and that light irradiation of such impregnated cells resulted in significant cell death. Thus, these properties of GO-HA could possibly make it especially promising for use in clinical photodynamic therapy.

Electrochemical sensor based on molecularly imprinted membranes at platinum nanoparticles-modified electrode for determination of 17ß-estradiol.

In this paper, an electrochemical sensor for 17ß-estradiol (E2) based on the molecular imprinting polymer (MIP) membranes had been constructed. 6-mercaptonicotinic acid (MNA) and E2 were first assembled on the surface of platinum nanoparticles-modified glassy carbon electrode (PtNPs/GCE) by the formation of Pt-S bonds and hydrogen-bonding interactions, and subsequently the polymer membranes were formed by electropolymerization. Finally, a novel molecularly imprinted sensor (MIS) was obtained after removal of E2. Experimental parameters such as deposition time, scan cycles, pH value and accumulation condition were optimized. Under optimal conditions, the MIS exhibited a large adsorption capacity and high selectivity. A good linearity was obtained in the range of 3.0×10(-8)-5.0×10(-5)molL(-1) (r=0.996) with an estimated detection limit of 1.6×10(-8)molL(-1). MIS had been successfully used to analyze E2 in water samples without complex pretreatment. Meanwhile, the average recoveries were higher than 93.9% with RSD<3.7%. All results above reveal that MIS is an effective electrochemical technique to determine E2 real-time in complicated matrix.