Near-infrared-driven upconversion nanoparticles with photocatalysts through water-splitting towards cancer treatment.

Water splitting is promising, especially for energy and environmental applications; however, there are limited studies on the link between water splitting and cancer treatment. Upconversion nanoparticles (UCNPs) can be used to convert near-infrared (NIR) light to ultraviolet (UV) or visible (Vis) light and have great potential for biomedical applications because of their profound penetration ability, theranostic approaches, low self-fluorescence background, reduced damage to biological tissue, and low toxicity. UCNPs with photocatalytic materials can enhance the photocatalytic activities that generate a shorter wavelength to increase the tissue penetration depth in the biological microenvironment under NIR light irradiation. Moreover, UCNPs with a photosensitizer can absorb NIR light and convert it into UV/vis light and emit upconverted photons, which excite the photoinitiator to create H2, O2, and/or OH˙ via water splitting processes when exposed to NIR irradiation. Therefore, combining UCNPs with intensified photocatalytic and photoinitiator materials may be a promising therapeutic approach for cancer treatment. This review provides a novel strategy for explaining the principles and mechanisms of UCNPs and NIR-driven UCNPs with photocatalytic materials through water splitting to achieve therapeutic outcomes for clinical applications. Moreover, the challenges and future perspectives of UCNP-based photocatalytic materials for water splitting for cancer treatment are discussed in this review.

Effect of epichlorohydrin treatment on the coating process and performance of high-barrier paper packaging.

The fabrication of coated papers using hydrophilic and biodegradable polymers is important for developing sustainable packaging materials with high barrier and superior mechanical properties. However, water, which is used as the solvent in the paper coating process using hydrophilic polymers, deforms the shape of the paper and deteriorates performance. Therefore, we propose a new coating process that treats Kraft paper (KP) with epichlorohydrin (ECH) as a binder before the coating process. Crosslinked polyvinyl alcohol is coated on the ECH-treated KP using a solution casting method. ECH maintains the shape of the paper and improves coating uniformity; significantly enhances interfacial interactions, which increases barrier properties and sealing strength; and extends the shelf life of biscuits by reducing oxygen and moisture permeability. An ecotoxicity test using Lolium multiflorum demonstrates an insignificant phytotoxicity level for the as-prepared coated papers. Thus, ECH-treated KP is a potential candidate for high-barrier food packaging.

A Breakthrough in Photocatalytic Wastewater Treatment: The Incredible Potential of g-C3N4/Titanate Perovskite-Based Nanocomposites.

Water pollution has emerged as a major global environmental crisis due to the massive contamination of water resources by the textile dyeing industry, organic waste, and agricultural residue. Since water is fundamental to life, this grave disregard puts lives at risk, making the protection of water resources a serious issue today. Recent research has shown great interest in improving the photocatalytic performance of graphitic carbon nitride (g-C3N4) for wastewater treatment. However, the photocatalytic removal activity of pure g-C3N4 is poor, owing to its minimal surface area, fast recombination of photo-generated electron-hole pairs, and poor light absorption. Recently, titanate perovskites (TNPs) have attracted significant attention in both environmental remediation and energy conversion due to their exceptional structural, optical, physiochemical, electrical, and thermal properties. Accordingly, TNPs can initiate a variety of surface catalytic reactions and are regarded as an emerging category of photocatalysts for sustainability and energy-related industries when exposed to illumination. Therefore, in this review article, we critically discuss the recent developments of extensively developed g-C3N4/TNPs that demonstrate photocatalytic applications for wastewater treatment. The different synthetic approaches and the chemical composition of g-C3N4/TNP composites are presented. Additionally, this review highlights the global research trends related to these materials. Furthermore, this review provides insight into the various photocatalytic mechanisms, including their potential impact and significance. Also, the challenges faced by such materials and their future scope are discussed.

Hydrothermal Synthesis of Functionalized Carbon Nanodots and Their Clusters as Ionic Probe for High Sensitivity and Selectivity for Sulfate Anions with Excellent Detection Level.

Nitrogen-doped carbon nanodots (CNDs) were synthesized and utilized as sensing probes to detect different anions and metallic ions within aqueous solutions. The pristine CNDs were developed through a one-pot hydrothermal synthesis. o-Phenylenediamine was used as the precursor. A similar hydrothermal synthesis technique in the presence of polyethylene glycol (PEG) was adopted to form the PEG-coated CND clusters (CND-100k). Through photoluminescence (PL) quenching, both CND and PEG-coated CND suspensions display ultra-high sensitivity and selectivity towards HSO4- anions (Stern-Volmer quenching constant (KSV) value: 0.021 ppm-1 for CND and 0.062 ppm-1 for CND-100k) with an ultra-low detection limit (LOD value: 0.57 ppm for the CND and 0.19 ppm for CND-100k) in the liquid phase. The quenching mechanism of N-doped CNDs towards HSO4- ions involves forming the bidentate as well as the monodentate hydrogen bonding with the sulfate anionic moieties. The detection mechanism of metallic ions analyzed through the Stern-Volmer formulation reveals that the CND suspension is well suited for the detection of Fe3+ (KSV value: 0.043 ppm-1) and Fe2+ (KSV value: 0.0191 ppm-1) ions, whereas Hg2+ (KSV value: 0.078 ppm-1) sensing can be precisely performed by the PEG-coated CND clusters. Accordingly, the CND suspensions developed in this work can be employed as high-performance PL probes for detecting various anions and metallic ions in the liquid phase.

Regeneration Approach to Enhance the Antimicrobial and Antioxidant Activities of Chitosan for Biomedical Applications.

Owing to its biodegradability, non-toxicity, and biocompatibility, chitosan (Cs) is a ubiquitous biopolymer. However, applications of Cs are limited owing to the existence of strong inter- and intra-molecular hydrogen bonds within its network. To address this issue, we regenerated medium-molecular-weight Cs to enhance the physico-chemical and functional properties using a cationic approach. Accordingly, alkaline modification was employed to introduce an additional positive charge to the amine functional groups of Cs and moderately disintegrate the inter- and intra-hydrogen bonds. The chemical structure of Cs and regenerated chitosan (RCs) was confirmed through Fourier transform infrared and 1H-NMR spectroscopy. RCs showed higher zeta potential value compared to Cs. Additionally, using X-ray diffraction, RCs exhibited low crystallinity, which can be attributed to the repulsive force caused by the positive surface charge and the destruction of hydrogen bonds. The RCs exhibited stronger antioxidant activity than Cs. Furthermore, the minimum inhibition concentrations (MICs) of RCs against Escherichia coli and Staphylococcus aureus were reduced by almost four times compared with those of Cs. The superior functional properties of RCs can be attributed to the formation of a polycationic structure after alkaline modification. Thus, RCs can be introduced as potent agents for various biomedical purposes.

Water-induced shape memory behavior of poly (vinyl alcohol) and p-coumaric acid-modified water-soluble chitosan blended membrane.

Shape memory polymer (SMP), composites and blends need to be prepared to improve the properties or obtain new functions of SMPs. In this work, we successfully prepared p-coumaric acid-modified water-soluble chitosan (M-Cs) and poly (vinyl alcohol) blended membrane (PVA/M-Cs) by a simple solution casting method to enhance its physico-chemical properties, including water-induced shape memory behavior. M-Cs were synthesized from native chitosan (Cs) using carbodiimide chemistry. After the addition of M-Cs into the PVA polymer matrix, it exhibited better water-induced shape memory behavior and shape recovery ratio reach nearly 100 %. Moreover, the water contact angle value declined after the addition of Cs or M-Cs in to the PVA polymer matrix. Based on these findings, the respective blended membranes will be able to broaden the applications of SMPs in many sectors, especially in the biomedical field, which requires water as the main stimulus.

Preparation and characterization of ferulic acid-modified water soluble chitosan and poly (γ-glutamic acid) polyelectrolyte films through layer-by-layer assembly towards protein adsorption.

In this study, ferulic acid-modified water soluble chitosan and poly (γ-glutamic acid) polyelectrolyte multilayers films were constructed through the layer-by-layer (LBL) self-assembly technique. Chitosan (CS) or ferulic acid modified chitosan (MCS) and Poly (γ-glutamic acid) (PGA) was alternately deposited on the surface of glass substrate for the enhancement of surface modification. The obtained films were characterized by Fourier transform spectroscopy (FTIR), X-ray diffractometry (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and water contact angle to study its physico-chemical properties including protein absorption. The (PGA/MCS) films showed intense deposition of multilayers built upon the surface roughness and an increase in the exponential growth of multilayer films by UV-vis spectroscopy. Water contact angle indicated that the (PGA/MCS) films performed well with good wettability due to the increase in the number of layers. The LBL multilayer coatings of (PGA/MCS) films surface possessed a reduced amount of protein adsorption. These results indicated that it can resist the protein adsorption and can enhance the biocompatibility towards the biomedical application through the protein interaction. The (PGA/MCS) films has the potential to utilization as a good biomaterial for biomedical purposes to intensify the bio-active surface.

Isolation, process optimisation and characterisation of the protein from the de-oiled cake flour of Madhuca latifolia.

This work reports the isolation of the protein from the flour of an underutilised agro waste, a de-oiled cake of Madhuca latifolia using the bis (2-ethylehexyl) sodium sulfosuccinate salt reverse micelle and the characterisation of the protein through various techniques. The experimental conditions for the extraction were optimised using Box-Behnken design. The highest yield of the protein was achieved when the extraction parameters, i.e. KCl concentration, KCl amount, and pH of the medium, were 0.5 M, 1.25 ml, and 9.02, respectively. The experimental yield (75.56%) obtained under the optimised conditions matched extremely well with the predicted yield (75.19%). The analysis of the biochemical composition envisaged the occurrence of 2S albumin, 7S globulin, and 11S globulin as the major components in the protein. The X-ray diffraction pattern supported the ß-sheets structure of the protein. The imaging of the protein through a scanning electron microscope revealed the shape and surface of the protein to be spherical and smooth, respectively. Thus, the protein isolate of the de-oiled cake flour of Madhuca latifolia could be utilised towards food product development and relevant fields.

Modification of different molecular weights of chitosan by p-Coumaric acid: Preparation, characterization and effect of molecular weight on its water solubility and antioxidant property.

In this study, we modified three different molecular weights of chitosan by using p-Coumaric acid (p-CA) for enhancing their water solubility and antioxidant property. The chemical and physical properties of all native chitosan and its modified products were determined by Fourier transform spectroscopy (FTIR), ninhydrin assay, Folin-Ciocalteu reagent procedure, thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), high performance of liquid chromatography (HPLC), X-ray diffraction (XRD), water solubility and antioxidant property (both DPPH assay and reducing power assay). Results showed that the water solubility and antioxidant property of modified product decreases, when molecular weight of corresponding native chitosan increases. The obtained modified product had good solubility over a wide range of pH. Thermal analysis (TGA and DSC) showed the lower thermal stability of the modified product than that of corresponding native chitosan. XRD pattern revealed that the crystallinity was less in modified product than that of respective chitosan. The enhanced partially water solubility and antioxidant property of all modified chitosan products might be a great advantage, while applied in a wide range of applications in the form antioxidant property in food, biomedical and cosmetic industry.

What Factors Affect Voluntary Uptake of Community-Based Health Insurance Schemes in Low- and Middle-Income Countries? A Systematic Review and Meta-Analysis.

INTRODUCTION: This research article reports on factors influencing initial voluntary uptake of community-based health insurance (CBHI) schemes in low- and middle-income countries (LMIC), and renewal decisions. METHODS: Following PRISMA protocol, we conducted a comprehensive search of academic and gray literature, including academic databases in social science, economics and medical sciences (e.g., Econlit, Global health, Medline, Proquest) and other electronic resources (e.g., Eldis and Google scholar). Search strategies were developed using the thesaurus or index terms (e.g., MeSH) specific to the databases, combined with free text terms related to CBHI or health insurance. Searches were conducted from May 2013 to November 2013 in English, French, German, and Spanish. From the initial search yield of 15,770 hits, 54 relevant studies were retained for analysis of factors influencing enrolment and renewal decisions. The quantitative synthesis (informed by meta-analysis) and the qualitative analysis (informed by thematic synthesis) were compared to gain insight for an overall synthesis of findings/statements. RESULTS: Meta-analysis suggests that enrolments in CBHI were positively associated with household income, education and age of the household head (HHH), household size, female-headed household, married HHH and chronic illness episodes in the household. The thematic synthesis suggests the following factors as enablers for enrolment: (a) knowledge and understanding of insurance and CBHI, (b) quality of healthcare, (c) trust in scheme management. Factors found to be barriers to enrolment include: (a) inappropriate benefits package, (b) cultural beliefs, (c) affordability, (d) distance to healthcare facility, (e) lack of adequate legal and policy frameworks to support CBHI, and (f) stringent rules of some CBHI schemes. HHH education, household size and trust in the scheme management were positively associated with member renewal decisions. Other motivators were: (a) knowledge and understanding of insurance and CBHI, (b) healthcare quality, (c) trust in scheme management, and (d) receipt of an insurance payout the previous year. The barriers to renewal decisions were: (a) stringent rules of some CBHI schemes, (b) inadequate legal and policy frameworks to support CBHI and (c) inappropriate benefits package. CONCLUSION AND POLICY IMPLICATIONS: The demand-side factors positively affecting enrolment in CBHI include education, age, female household heads, and the socioeconomic status of households. Moreover, when individuals understand how their CBHI functions they are more likely to enroll and when people have a positive claims experience, they are more likely to renew. A higher prevalence of chronic conditions or the perception that healthcare is of good quality and nearby act as factors enhancing enrolment. The perception that services are distant or deficient leads to lower enrolments. The second insight is that trust in the scheme enables enrolment. Thirdly, clarity about the legal or policy framework acts as a factor influencing enrolments. This is significant, as it points to hitherto unpublished evidence that governments can effectively broaden their outreach to grassroots groups that are excluded from social protection by formulating supportive regulatory and policy provisions even if they cannot fund such schemes in full, by leveraging people's willingness to exercise voluntary and contributory enrolment in a community-based health insurance.