Fabricating hierarchical ZSM-5 to induct long chain antioxidant coenzyme Q10 for biomedical application

The study investigates the hydrophobic antioxidant Coenzyme Q10 (CoQ10) adsorption over industrially relevant hierarchical ZSM-5 for potential therapeutic applications. The designing of hierarchical nanocomposites was optimized with two different NaOH/CTAB ratios (0.18 and 0.62) over ZSM-5 (SiO₂/Al₂O₃ = 22–27) of different crystal sizes (0.5 µm, 2.0 µm and 3.0 µm) and different SiO₂/Al₂O₃ ratios (23, 80, 280 and 1500) through top-down approach. Hydrothermal stability of samples was studied using 100% water steam at 700 °C and 750 °C for 2 h, respectively. Reassembling nano ZSM-5 into hierarchical composite was found to exhibit ordered/disordered hexagonal mesophase depending on alkaline treated ZSM-5 crystal sizes and silica to alumina ratios. The phase changes were analyzed using different textural characterizations such as X-ray diffraction, BET surface area, ammonia desorption technique, ²⁷Al MAS NMR, thermogravimetric analysis and transmission electron microscope. 21 different nanoformulations were screened for CoQ10 adsorption and subsequently selected samples were applied for curcumin and ascorbic acid adsorption. Hierarchical ZSM-5 with SiO₂/Al₂O₃ ratio 80 (ZSM-5-80 (0.62)) was found to be steam stable and optimum with highest Q10 adsorption (55%). The adsorption influence over different crystal size and silica to alumina ratios, clearly showed the dependency over synergistic action of textural characteristics such as external surface area, pore volume, and weak acidity. The structured nanosupports with pore sizes between 3 and 4.0 nm were found to exhibit highest CoQ10 adsorption.     

Micromechanical Photonics

Micromechanical photonics is evolving in interdisciplinary research and engineering fields to merge independently developed technologies based on optics, mechanics, electronics and physical/chemical sciences. Manufacturing technologies such as semiconductor lasers, surface-micromachining, and bulk-micromachining are promoting technology fusion. New conceptual frameworks such as very short external cavity tunable laser diodes, tunable filters, optical scanners, free-space micro-optical elements, integrated optical heads, a photothermal microresonator, optical tweezers, and optical rotators are now appearing.     

Nonlinear optical absorption of zinc-phthalocyanines in polymeric matrix

We realized and investigated films of zinc-phtalocyanines into poly(methylmethacrylate) (PMMA) for optical limiting applications. The ratio by weight of the compound to the host polymer was 0.083% and 0.15%. Linear optical characterization of films, performed by spectrophotometry, show a low degree of molecular aggregation of zinc-phtalocyanines in the polymeric matrix.Two different type of nonlinear optical investigation were performed separately on the obtained films. Measurements of nonlinear transmission were carried out using a ns Nd:Yag laser followed by OPO (532 nm) and a nonlinear response was observed. From the experimental data, the nonlinear absorption coefficient β was retrieved and found to be 29 and 43 cm/GW, respectively. The measurements of β was also performed via the z-scan technique on the same films, using 100 fs pulses at 800 nm. At this wavelength, the nonlinear absorption coefficient was evaluated to be 0.40 and 0.23 cm/GW.     

Studies on hydrolytic degradation of poly(ester-anhydride)s based on oligosuccinate and aliphatic diacids

This paper describes synthesis, characteristics and hydrolytic degradation of functional poly(ester-anhydride)s based on oligo(3-allyloxy-1,2-propylene succinate) (OSAGE) and aliphatic diacids (DA). The polymers were obtained by polycondensation of OSAGE with adipic (ADP), sebacic (SBA) or dodecanedicarboxylic acid (DDC). The carboxyl groups in OSAGE and in diacids were converted to mixed anhydride groups by acetylation with acetic anhydride. After that, prepolymers thus obtained were condensed in vacuum to yield poly(ester-anhydride)s. The structure of copolymers was confirmed by NMR spectroscopy. Influence of the kind of diacid and the OSAGE to diacid ratio on selected properties of poly(ester-anhydride)s were examined. Poly(ester-anhydride)s were subjected to hydrolytic degradation at 37 °C, in aqueous phosphate buffer solution of pH 7.41 (PBS). The course of degradation was monitored by determination of weight loss of samples, ¹H NMR and DSC. Fracture surfaces of samples during degradation were examined by scanning electron microscopy.     

Infrared spectroscopy provides a green analytical chemistry tool for direct diagnosis of cancer

Diagnosis of cancer is one of the most important aspects of medical research and has become the main aim of biomedical investigations. Misdiagnosis is the main drawback in most of the diagnostic routes introduced, while some of these methods are invasive and expensive.Recently, infrared spectroscopy (IR) was proposed as a rapid, accurate and sensitive technique in biomedical research, especially for detection of patterns of illness. We discuss research into cancer detection by IR, the role of data processing in quality assurance of the results obtained and novel proposals, such as bio-fluid analysis for diagnosis. We conclude that IR provides a novel green analytical chemistry approach to clinical oncology and cancer research.     

Interactions of amphiphilic block copolymers with lipid model membranes

Studies on interactions between amphiphilic block copolymers and lipid membranes have been focused traditionally on ABA triblock copolymers of poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), widely due to their commercial availability. However, new architectures of amphiphilic block copolymer have been synthesized in recent years partially taking advantage of new polymerization techniques. This review focuses on amphiphilic block copolymers with potential biological activity and on model membrane systems used for studying interactions with such block copolymers. Experimental methods to study block copolymer–phospholipid interactions in Langmuir monolayers, liposomes, and planar bilayers are summarized. This work is intended to convey a better understanding of amphiphilic block copolymers used for in vitro and in vivo experiments in medicine and pharmacy. Recent developments and open questions are addressed.     

Numerical analysis of amplification characteristics of ErxY2 − xSiO5

The gain characteristics of Er_xY_2 − xSiO₅ waveguide amplifiers have been investigated by solving rate equations and propagation equations. The gain at 1.53 μm as a function of waveguide length, Er³⁺ concentration and pump power is studied pumping at three different wavelengths of 654 nm, 980 nm and 1480 nm, respectively. The optimum Er³⁺ concentrations of 1 × 10²¹ cm^− 3-2 × 10²¹ cm^− 3 with the high gain are obtained for all three pump wavelengths. Pumping at 654 nm wavelength is shown to be the most efficient one due to weak cooperative upconversion. A maximum 16 dB gain at 1 mm waveguide length under a 30 mW pump with Er³⁺ concentration of 1 × 10²¹ cm^− 3 is demonstrated pumping at 654 nm wavelength.     

Compact optical delay line for long-range scanning

We proposed and demonstrated an optical delay line composed of all reflective components for long-range scanning without walk-off problem. The optical delay line consists of a retro-reflector, an inclined reflection mirror and a scanning mirror. The size of the optical delay line is within 2 cm × 2 cm and the scanning range can reach 2.9 mm when the beam is incident at the pivot of the scanning mirror and the vibration angle of the scanning mirror is 9.6°. The scanning range can be further increased when the pivot of the scanning mirror is laterally deviated from the incident beam. The optical delay line possesses the advantages that it is compact, easy to fabricate and can perform rapid scanning in large scanning range without walk-off problem. The optical delay line was demonstrated with a low-coherence reflectometer where the scanning rate was 400 Hz. A higher scanning rate can be achieved when a scanning component with higher scanning rate is applied.