Riboflavin Sodium Phosphate Research Articles

Aqueous Polysulfide-Based Redox Flow Battery with Soluble Molecular Catalysts

Aqueous polysulfide-based redox flow batteries (RFBs) are promising for large-scale energy storage applications due to their low cost and high safety1. However, polysulfide negolyte suffers from poor kinetics, resulting in low operating current density and low energy efficiency2-5. Herein, we proposed a molecular catalyst strategy to transfer the sluggish electrochemical polysulfide reduction reaction to a fast chemical reaction via homogeneous catalysis. Inspired by the electron transport chain in the respiratory process, we selected riboflavin sodium phosphate (FMN-Na) as the molecular catalyst to transfer electrons from electrode to polysulfide with the disulfide bond cleavage6. The reaction rate (or turnover frequency) kobs is determined to be 33 s–1 at 1 M K2S4 solution, and this spontaneous chemical electron transfer process is verified by ultraviolet-visible light spectroscopy. In the polysulfide-ferrocyanide (S-Fe) RFB, the overpotential is dramatically decreased from over 800 mV to 241 mV at 30 mA cm–2 with the assistance of FMN-Na as the molecular catalysts. The catalyzed S-Fe RFB and polysulfide-iodide RFB showed stable operation for over 1,000 cycles at 40 mA cm–2. This work offers a simple but effective method to resolve the bottleneck for aqueous polysulfide-based RFBs, and such a homogeneous catalysis strategy may shed light on other flow battery systems with poor kinetics. We will combine operando spectroscopic techniques and theoretical calculation to discuss the possible reaction mechanism and intermediate.AcknowledgmentThis work is supported by two grants from the Research Grants Council (RGC) T23-713/22-R and RFS2223-4S03. Reference Y. Yao, J. Lei, Y. Shi, F. Ai and Y.-C. Lu, Nat. Energy, 2021, 6, 582-588. Z. Li and Y.-C. Lu, Nat. Energy, 2021, 6, 517-528. X. Wei, G.-G. Xia, B. Kirby, E. Thomsen, B. Li, Z. Nie, G. G. Graff, J. Liu, V. Sprenkle and W. Wang, J. Electrochem. Soc., 2015, 163, A5150. Z. Li, M. S. Pan, L. Su, P.-C. Tsai, A. F. Badel, J. M. Valle, S. L. Eiler, K. Xiang, F. R. Brushett and Y.-M. Chiang, Joule, 2017, 1, 306-327. J. Lei, Y. Yao, Y. Huang and Y.-C. Lu, ACS Energy Lett., 2023, 8, 429-435. J. Lei, Y. Zhang, Y. Yao, Y. Shi, K. L. Leung, J. Fan and Y.-C. Lu, Nat. Energy, 2023, DOI: 10.1038/s41560-023-01370-0.

Fluoride induces immunotoxicity by regulating riboflavin transport and metabolism partly through IL-17A in the spleen

The impairment of the immune system by fluoride is a public health concern worldwide, yet the underlying mechanism is unclear. Both riboflavin and IL-17A are closely related to immune function and regulate the testicular toxicity of fluoride. However, whether riboflavin or IL-17A is involved in fluoride-induced immunotoxicity is unknown. Here, we first established a male ICR mouse model by treating mice with sodium fluoride (NaF) (100 mg/L) via the drinking water for 91 days. The results showed that fluoride increased the expression of the proinflammatory factors IL-1β and IL-17A, which led to splenic inflammation and morphological injury. Moreover, the expression levels of the riboflavin transporters SLC52A2 and SLC52A3; the transformation-related enzymes RFK and FLAD1; and the key mitochondrial functional determinants SDH, COX, and ATP in the spleen were measured via real-time PCR, Western blotting, and ELISA. The results revealed that fluoride disrupted riboflavin transport, transformation, metabolism, and mitochondrial function. Furthermore, wild-type (WT) and IL-17A knockout (IL-17A-/-) C57BL/6 J male mice of the same age were treated with NaF (24 mg/kg·bw, equivalent to 100 mg/L) and/or riboflavin sodium phosphate (5 mg/kg·bw) via gavage for 91 days. Similar parameters were evaluated as above. The results confirmed that fluoride increased riboflavin metabolism through RFK but not through FLAD1. Fluoride also affected mitochondrial function and activated neutrophils (marked with Ly6g) and macrophages (marked with CD68) in the spleen. Interestingly, IL-17A partly mediated fluoride-induced riboflavin metabolism disorder and immunotoxicity in the spleen. This work not only reveals a novel toxic mechanism for fluoride but also provides new clues for exploring the physiological function of riboflavin and for diagnosing and treating the toxic effects of fluoride in the environment.

HPLC/MS Analysis of Riboflavin Sodium Phosphate Consisting of Several Structural Isomers Together with Thiamine HCL, Pyridoxine HCL, Dexpanthenol, and Nicotinamide in A Multi-Vitamin Injection Solution

We were tasked with testing a multicomponent aqueous solution for injection used in medicine. The composition of the solution included the following components: Riboflavin sodium phosphate (vitamin B2), Thiamine HCl (vitamin B1), Pyridoxine HCl (vitamin B), Dexpanthenol (vitamin B5), and Nicotinamide (vitamin B3), also benzyl alcohol. The complexity of the simultaneous determination of these components was that they differ in their acid-base properties, physical-chemical properties, concentration in solution, and solubility in the mobile phase. The key to solving this task is the correct choice of method for analyzing riboflavin sodium phosphate in each vitamin mixture. Riboflavin is taking particular attention because this component has a few isomers that are separated by HPLC.

Nonconductive layered hexagonal boron nitride preparation via a co-exfoliation strategy and nanohybrid coating construction for corrosion protection

Hexagonal boron nitride (h-BN), an analogue of graphene with similar layered structure, is considered as the promising material in place of graphene for application as nanofiller into polymeric matrices to develop the smart coatings for corrosion protection of metallic substrates, owing to its mechanical robustness and thermal stability together with unique electrically insulating nature. In this work, on the basis of a co-exfoliation strategy, h-BN were exfoliated by riboflavin sodium phosphate (FMN) intercalator, assisted with ball-milling to obtain few-layered nanosheets with improved water-dispersibility as well as improve their compatibility with waterborne epoxy matrix. The results from electrochemical measurement and corrosion product analysis indicate that the incorporation of only 1.0 wt% FMN-exfoliated h-BN (h-BN@FMN nanohybrids) content into waterborne epoxy matrix can realize the optimized long-term corrosion resistance of composite coatings in 3.5 wt% NaCl solution. The two-dimensional morphology and impenetrability of h-BN, together with the compatibility of waterborne epoxy system from the bridge role of FMN molecules to act as a physical barrier against corrosive species (i.e., H2O, Cl− and O2), are the main reasons behind the prominent anticorrosion performance of our composite coating.

Towards the Enhanced Lithium‐Ion Batteries by Designing (N, Co, Zr, P) Tetra‐Doped Porous Carbon Anode

AbstractHeteroatom‐doped porous carbons have stable structures, high electron/ion transport efficiencies, and rich electroactive sites, which are of great significance to energy storage devices. The potential synergistic effects arising from the multi‐element doping benefit to improve the electrochemical behavior of porous carbon. In this paper, a facile doping strategy has been proposed to prepare the (N, Co, Zr, P) tetra‐doped porous carbon spheres (PCS) for enhanced lithium‐ion batteries (LIBs). The metal‐organophosphine framework (MOPF) as precursor is synthesized by utilizing riboflavin sodium phosphate as organic ligand coordinating with cobalt and zirconium ions. Through carbonizing MOPF, the (N, Co, Zr, P) tetra‐doped PCS can be obtained. As the anode for LIBs, the (N, Co, Zr, P) tetra‐doped PCS exhibits highly reversible capacity of 761 mAh g−1 at 0.1 A g−1 after 100 cycles, excellent rate performance of 126 mAh g−1 even at a high current density of 2 A g−1. The results feature that the unique 3D structure and superior local electron transport properties of (N, Co, Zr, P) tetra‐doped PCS promote the Li+ diffusion and adsorption, which improve the electrochemical properties. Moreover, the mechanism analysis realizes that the Li+ storage of (N, Co, Zr, P) tetra‐doped PCS is determined by the capacitive behavior at high scan rate, highlighting the significance of the heteroatom doping. Therefore, the (N, Co, Zr, P) tetra‐doped PCS should be considered as prominent candidate for high‐performance LIBs anodes.

Fabrication of multifunctional bio-macromolecule organic-inorganic hybrid system for protein silk: Photochromic, UV protection, fire-proof and super durability

Nowadays, high value-added and multifunctional textiles have attracted widespread attention due to the changing demands of modern life. This study focused on the fabrication of silk with photochromism, flame retardancy, UV resistance and durability using riboflavin sodium phosphate (RSP) and various metal ions (Fe2+, Fe3+, Al3+, and Ti4+). Attractively, the photochromic performance was one of the most distinctive features of the modified silk, and the yellow silk fabric turned into fluorescent green under UV lamp. After a detailed comparison, it was determined that RSP/Fe3+ hybrid system was most effective in improving anti-UV performance of the silk with a high UPF of 25.8, achieving a “Good” level of UV protection. Specifically, it achieved a B1 fire protection with a low damaged-length of 9.4 cm and a high LOI of 28.3 %. Additionally, the modified silk showed the lowest smoke density, reducing by approximately 84.1 % versus that of pristine silk. Moreover, the modified silk was able to meet the B1 classification and the “Good” UV protection requirements even after 75 washing cycles, making it more durable than most functional textiles reported. The further analysis indicated that RSP and metal ions can synergistically enhance the condensed-phase action, thereby improving the fire resistance of silk.

Construction of sustainable, colored and multifunctional protein silk fabric using biomass riboflavin sodium phosphate

Construction of sustainable, colored and multifunctional protein silk fabric using biomass riboflavin sodium phosphate

Rapid preparation of hyperbranched β-CD functionalized hydroxyapatite based on host-guest reaction for cell imaging and drug delivery

Improving the biocompatibility and water dispersibility of hydroxyapatite (HAP) is an effective way to expand its application in biomedicine. Here, we present a nanosystem (HAP-β-CD-HPG) that is constructed by riboflavin sodium phosphate (HE) functionalized hydroxyapatite (HAP) and hyperbranched β-cyclodextrin (β-CD-HPG) through a simple, mild and rapid approach. Firstly, the successful construction of HAP-β-CD-HPG nanosystem is confirmed by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and so on. Next, Doxorubicin (DOX) is loaded onto HAP-β-CD-HPG with a high encapsulation potency (60.3%) and further use for the simultaneously cell-imaging and controlled release of the cytotoxic drug DOX. Furthermore, the pH-triggered DOX release process in A549 cancer cells can be visualized dynamically by tracking the fluorescence of HAP-β-CD-HPG and DOX. This work both provides a new protocol for the construction of dual-function nanosystem for imaging of cell cytoplasm and drug delivery via a simple approach and promotes a potential application of this diagnosis-therapy integrated system for cancer treatment in the future.

Surface-Fabrication of Fluorescent Hydroxyapatite for Cancer Cell Imaging and Bio-Printing Applications.

Hydroxyapatite (HAP) materials are widely applied as biomedical materials due to their stable performance, low cost, good biocompatibility and biodegradability. Here, a green, fast and efficient strategy was designed to construct a fluorescent nanosystem for cell imaging and drug delivery based on polyethyleneimine (PEI) and functionalized HAP via simple physical adsorption. First, HAP nanorods were functionalized with riboflavin sodium phosphate (HE) to provide them with fluorescence properties based on ligand-exchange process. Next, PEI was attached on the surface of HE-functionalized HAP (HAP-HE@PEI) via electrostatic attraction. The fluorescent HAP-HE@PEI nanosystem could be rapidly taken up by NIH-3T3 fibroblast cells and successfully applied to for cell imaging. Additionally, doxorubicin hydrochloride (DOX) containing HAP-HE@PEI with high loading capacity was prepared, and in-vitro release results show that the maximum release of DOX at pH 5.4 (31.83%) was significantly higher than that at pH 7.2 (9.90%), which can be used as a drug delivery tool for cancer therapy. Finally, HAP-HE@PEI as the 3D inkjet printing ink were printed with GelMA hydrogel, showing a great biocompatible property for 3D cell culture of RAW 264.7 macrophage cells. Altogether, because of the enhanced affinity with the cell membrane of HAP-HE@PEI, this green, fast and efficient strategy may provide a prospective candidate for bio-imaging, drug delivery and bio-printing.

Temperature and pH dual-responsive supramolecular hydrogels based on riboflavin sodium phosphate and 2,6-Diaminopurine with thixotropic and fluorescent properties

A novel temperature and pH dual-responsive supramolecular (TPS) hydrogels based on riboflavin sodium phosphate (RP) and 2,6-Diaminopurine (DAP) were fabricated and investigated. In this study, the TPS hydrogels were fabricated under different molar ratios of RP to DAP and analyzed with theoretical chemical calculations. These TPS hydrogels can form gels at room temperature and acidic conditions, and convert to sols at higher temperature and alkaline conditions. Thermal studies indicated that TPS hydrogels have thermally reversible properties. Rheological experiments related to frequency sweep experiment proved the formation of the TPS hydrogel. Time sweep experiments show the thixotropic properties of the gel. XRD pattern and SEM confirm that these complexes formed a new crystal structure. FTIR spectra show that the DAP and RP self-assemble through the H-bonding interaction. The UV–vis spectra show that in the visible region, the peaks of TPS hydrogel are red shift compared with TPS sol and RP solution. The fluorescence lifetime of TPS hydrogel increased to 4.1 ns longer than that of RP solution 2.6 ns.

Expanded validation of the effect and quality of a pathogen inactivation system based on riboflavin photochemistry on platelet bacterial contamination

BackgroundBacterial contamination still poses serious challenges to blood safety. Platelets have the highest bacterial contamination risk of all blood components.MethodsTwenty units of manual platelets were prepared from blood donated by our hospital, which were inoculated with Staphylococcus aureus and Escherichia coli suspensions. The riboflavin sodium phosphate solution was added into platelets, adjusted to a final concentration of 160 μmol/L. Platelets added into an illumination bag and placed in the inactivation system for riboflavin photochemistry at various doses. The inactivation effect of bacteria was evaluated on a Columbia blood agar plate by the plate counting method. Meanwhile, the blood routine, blood gas analysis, platelet aggregation test, and thromboelastogram of platelets before and after treatment were detected to evaluate the changes of platelet quality after treatment.Resultsthe inactivation effect of S. aureus and E. coli at the inactivation dose (16.9 J/cm2) could reach more than 4 logs. After treatment at 16.9 J/cm2, the blood routine results showed that the platelet count was significantly different (P<0.05), and the blood gas analysis showed that the oxygen partial pressure (pO2) and lactic acid concentration (cLac) were also significantly different (P<0.05). After 16.9 J/cm2 treatment, there was a significant difference between Arachidonic acid (AA) and Collagen (Cog) activator groups in the platelet aggregation experiment (P<0.05), but there was no significant difference in the main thrombelastogram (TEG) parameters (R value, K value, angle value, MA value) after treatment (P>0.05).ConclusionsThe inactivation effect of this set of blood component pathogen inactivation system on platelet bacterial contamination could be considered to meet actual clinical needs, with the inactivation treatment having little impact on platelet function.

ATP-triggered drug release system based on ZIF-90 loaded porous poly(lactic-co-glycolic acid) microspheres

Poly(lactic-co-glycolic acid) (PLGA) based microparticles have been widely applied in drug delivery system, but pristine PLGA particles suffers from low efficiency in release and non-targeted effect for drug delivery system. Inspired by cancer cells environment, we have fabricated an ATP-triggered delivery system based on porous PLGA microspheres covering drug-loaded ZIF-90. The system contains controlled doxorubicin releasing because ZIF-90 nanocrystals are easily collapsed under exposing to high-concentration ATP environment. In addition, ZIF-90@PLGA microparticles also perform low toxicity and 2.37 % hemolysis, and improved fluorescence intensity of doxorubicin by loading riboflavin sodium phosphate benefited from their partial Förster resonance energy transfer. This novel ATP-triggered drug delivery system based on porous PLGA particles could be widely utilized to design effective drug release biomaterials for gastric and lung cancer.

The lithium ions storage behavior of heteroatom-mediated echinus-like porous carbon spheres: From co-doping to multi-atom doping

This study proposed a facile method to prepare echinus-like porous carbon spheres (PCS) with different heteroatom doping for lithium ions battery (LIBs). A metal-organophosphine framework (MOPF) was synthesized by employing riboflavin sodium phosphate as an organic ligand to conjugate with metal ions and then carbonized at mild temperature, leading to the formation of heteroatom doped PCS (H-PCS). As a result, (N, P) co-, (N, P, Ni) tri-, (N, P, Co) tri- and (N, Ni, Co, P) tetra-doped PCS were obtained to examine the insight into lithium-ion storage behavior of H-PCS. It was found that the specific surface area, pore texture and structural defects of H-PCS were dependent on doping of heteroatoms as well as the charge transfer resistance and Li-ion diffusion coefficient. Significantly, the redox reaction potential during the charge/discharge could be mediated upon the doping. Thus, when evaluated as anode for LIBs, the (N, Ni, Co, P) tetra-doped PCS exhibited highly reversible capacity of 680 mAh g−1 at 0.1 A g−1, excellent rate capability (115.9 mAh g−1 at 1.0 A g−1) and superior cycling performance (399.6 mAh g−1 at 0.1 A g−1). Moreover, the cyclic voltammogram measurements demonstrated that the doping of metal atoms was favorable for improving the capacitive contribution of surface limited diffusion. Thus, this work highlighted the importance of HCP with defined doping which could be considered as one of the prominent candidates for high-performance LIBs’ anode.

MWCNT-riboflavin nanocomposite for collagen crosslinking: A green approach

Carbon nanotubes exhibit remarkable thermal and mechanical properties, so they may offer a structural reinforcement in hydrogels, e.g. cartilage, which could be used in regenerative medicine. The aim of the present work is to follow the principles of green chemistry to accomplish a one-step and solvent-free derivatization of oxidized multi-walled carbon nanotubes (MWNT) with riboflavin sodium phosphate (FMN). The viability of the MWNT-riboflavin (MWFMN) nanocomposite as a photosensitizer was tested for collagen crosslinking under sunlight. Results were compared with those obtained for free FMN under the same conditions. In addition, some samples were held in darkness as a control group. MWNT derivatization was demonstrated by ATR-FTIR spectroscopy, thermogravimetric analysis (TGA), and electron microscopy (SEM and TEM). The collagen crosslinking was characterized by DLS, ATR-FTIR, TGA and SEM. The results suggested that the use of the nanocomposite (MWFMN) improves the structural and thermal properties of collagen matrices.

A facile strategy to prepare (N, Ni, P) tri-doped echinus-like porous carbon spheres as advanced anode for lithium ion batteries

Heteroatom doped carbon nanomaterials are often employed as advanced anodes for lithium ion batteries (LIBs) because of their stable structure, high capacity and low cost. In this work, we proposed a novel strategy to synthesize high density (N, Ni, P) tri-doped echinus-like porous carbon spheres (PCS) by carbonizing a metal-organophosphine framework (MOPF) directly. The MOPF employs riboflavin sodium phosphate (C17H20N4NaO9P) as an organic ligand as well as a nitrogen and phosphorus source to conjugate with Ni(NO3)2 · 6H2O. As an anode for LIBs, PCS was demonstrated with discharge capacities that were able to reach 386.5 mAh · g−1 after 100 cycles at a current density of 0.05 A · g−1. Besides, the stable reversible capacities were obtained from ∼459 mAh · g−1 to ∼91.8 mAh · g−1 when the current density was varied from 0.05 to 1 A · g−1. The good anode performance is attributed to the unique structure of PCS and (N, Ni, P) tri-doping which introduces the additional capacities due to the presence of the ‘reservoir effect’. Moreover, the electrochemical analysis implied that the surface-limited capacitive behavior dominantly contributes to the lithium ion storage capacity of the PCS anode.

Evaluation of combined corneal cross-linking with LASIK in risky patients

Objective The aim of this study was to evaluate the efficacy and safety of ultraviolet A irradiation cross-linking on completion of laser-assisted in-situ keratomileusis (LASIK) in risky patients to avoid post-LASIK ectasia. Background Patients with thinner-than-normal corneas, irregular corneal astigmatism, asymmetry on corneal topography, against-the-rule astigmatism, or steeper-than-normal corneas have higher risk of development of post-LASIK ectasia which need improvement in surgical interference. Materials and methods Forty-eight eyes of 30 myopic patients presented for LASIK at Al-Fardous Eye and Dental Hospital, Zagazig, Egypt, between September 2013 and August 2014. The study group comprised risky patients with corneal thickness of at least 480 μm and postoperative residual stromal thickness of at least 300 μm. After reflecting the flap, 0.1% riboflavin sodium phosphate solution was applied on the bare stromal bed and left to be soaked in for 60 s, and then the patient was positioned with the ultraviolet light (typically 365-370 μm). Results The study proved that there was an improvement in mean spherical error from −4.05 ± 1.19 preoperatively to −0.98 ± 0.12 on the second day postoperatively, and it improved to −0.59 ± 0.49, −0.49 ± 0.39, and −0.39 ± 0.36 at 1, 3, and 6 months postoperatively, respectively. These results showed a statistically highly significant difference (P 0.05) because we compared the results with the preoperative best-corrected visual acuity. Conclusion Application of riboflavin with ultraviolet after LASIK in risky patients improves refractive errors (spherical and cylindrical errors) and prevents post-LASIK corneal ectasia.

Abstract 13194: The Effects of Methotrexate Therapy on Myocardial Infarction With ST-Segment Elevation (TETHYS Trial)

Introduction: Acute myocardial infarction provokes inflammatory activation. Methotrexate is one drug that has been shown to have anti-ischemic effects in experimental studies. Hypothesis: Methotrexate could reduce inflammation and the ischemia area in acute myocardial infarction Methods: We randomly assigned patients with myocardial infarction with ST-segment elevation to receive either methotrexate (0.05 mg/kg bolus followed by 0.05 mg/kg/h for 6 h) or matching placebo (riboflavin sodium phosphate 0.1%, in order to preserve double-blinding) at a ratio of 1:1. Patients in both groups were given a 5mg single dose of folic acid. The primary endpoint was infarct size, determined by the area under the curve (AUC) for creatine kinase (CK) release. Secondary endpoints were AUC of CK-MB and AUC of troponin I; peak CK, peak CK-MB and troponin I; B-type natriuretic peptide (BNP) level, high-sensitivity C-reactive protein (hsCRP) result and erythrocyte sedimentation rate (ESR); left ventricular ejection fraction (LVEF); TIMI frame count; Killip score; mortality and reinfarction incidence. The safety endpoint was the incidence of adverse reactions. Results: We included 84 patients. The AUC of CK was 78,861.00 in the methotrexate group and 68,088.00 in the placebo group (P=0.10). Patients given methotrexate and placebo exhibited, respectively, AUC for CK-MB of 9,803.40 and 8,037.00 (P=0.42); AUC for troponin I of 3,691.11 and 2,132.63 (P=0.09); peak CK of 2,806.00 and 2,147.00 (P=0.05), peak CK-MB of 516.00 and 462.25 (P=0.25) and peak troponin I of 121.00 and 85.05 (P=0,06). At 3 months, LVEF was lower in patients who received methotrexate (48.97±14.09%) than in patients given placebo (56.37±9.97%) (P=0.01). There were no differences in hsCRP, ESR, BNP, Killip scores or TIMI frame count. There were also no differences in reinfarction or mortality rates or in incidence of side effects, with the exception of higher median serum glutamic-pyruvic transaminase (SGPT) levels in the methotrexate group. Conclusions: Methotrexate did not reduce infarction size and worsened LVEF at 3 months.

Efficiency optimization of a microwave-assisted Fenton-like process for the pretreatment of chemical synthetic pharmaceutical wastewater

Chemical synthetic pharmaceutical wastewater was treated using a microwave-assisted Fenton-like (MW-Fenton-like) process with satisfactory efficiency. Firstly, based on the MW power chosen, three factors, namely ferric sulfate dose, hydrogen peroxide dose, and total organic carbon (TOC) concentration were used to investigate the improvement in the efficiency of the MW-Fenton-like process for pharmaceutical wastewater pretreatment. Ferric sulfate and hydrogen peroxide doses (ferric sulfate 1.5 mg/L and hydrogen peroxide 10 mL/L) were low, after mixing well, oxidation decomposition was explored without acidification, this time was short (6 min). Under optimal conditions, the removal rate of TOC was with satisfactory effects (57.5%). Furthermore, the initial pH value was selected without adjustment when the MW radiation started. It was unnecessary to extend the radiation time because no hydrogen peroxide existed in system with the radiation time of 8 min. The influent was unnecessary to be diluted. Biodegradation of the wastewater could be elevated well (BOD5/COD arose from 0.23 to 0.40). Moreover, all of coloration from Riboflavin sodium phosphate dissolved (<15 mg/1 L wastewater) was completely removed in the sample. Finally, according to the TOC removal, the second step (flocculation precipitation) was as equally important as the first step (oxidation decomposition), though ferric sulfate dose was low. The effect of biological treatment was unsatisfactory compared with MW-Fenton-like process.

Clinical investigation in effect of riboflavin sodium phosphate on prevention and treatment for patients with radiotherapy related esophagitis.

To investigate the clinical effect of riboflavin sodium phosphate on prevention of radiotherapy related esophagitis (RRE). This retrospective study involved 55 patients with middle and advanced esophageal cancer who were divided into an experimental group of 28 and a control group of 27 patients. Those in the experimental group were treated with riboflavin sodium phosphate combined with conventional symptomatic treatment during radiotherapy; while patients in control group received the latter alone. The incidence and degree of RRE were compared after radiotherapy. The incidences of RRE in experimental and control group were 53.5% and 81.4%, respectively (p<0.05); the incidence of stages III and IV RRE in the experimental group was 17.8%, while in the control group it was 44.4% (p<0.05). Riboflavin sodium phosphate could significantly prevent RRE and reduce the incidence of stage III and IV disease. These results were worthy of further confirmation by randomized controlled trials.

Tailoring controlled-release oral dosage forms by combining inkjet and flexographic printing techniques

We combined conventional inkjet printing technology with flexographic printing to fabricate drug delivery systems with accurate doses and tailored drug release. Riboflavin sodium phosphate (RSP) and propranolol hydrochloride (PH) were used as water-soluble model drugs. Three different paper substrates: A (uncoated woodfree paper), B (triple-coated inkjet paper) and C (double-coated sheet fed offset paper) were used as porous model carriers for drug delivery. Active pharmaceutical ingredient (API) containing solutions were printed onto 1cm×1cm substrate areas using an inkjet printer. The printed APIs were coated with water insoluble polymeric films of different thickness using flexographic printing. All substrates were characterized with respect to wettability, surface roughness, air permeability, and cell toxicity. In addition, content uniformity and release profiles of the produced solid dosage forms before and after coating were studied. The substrates were nontoxic for the human cell line assayed. Substrate B was smoothest and least porous. The properties of substrates B and C were similar, whereas those of substrate A differed significantly from those of B, C. The release kinetics of both printed APIs was slowest from substrate B before and after coating with the water insoluble polymer film, following by substrate C, whereas substrate A showed the fastest release. The release rate decreased with increasing polymer coating film thickness. The printed solid dosage forms showed excellent content uniformity. So, combining the two printing technologies allowed fabricating controlled-release oral dosage forms that are challenging to produce using a single technique. The approach opens up new perspectives in the manufacture of flexible doses and tailored drug-delivery systems.