Low Molecular Weight Products Research Articles

Understanding sulfonated kraft lignin re-polymerization by ultrafast reactions in supercritical water

Re-polymerization reactions are a commonly reported issue on the way to the higher recovery of monomers from lignin. The reactivity of monomers obtained from lignin depolymerization and their contribution to the re-polymerization in supercritical water (SCW) was investigated. Sulfonated Kraft lignin (SKL) was used along with four monomers: vanillin, vanillic acid, vanillyl alcohol and acetovanillone. Indulin Kraft lignin was also employed as the reference to understand the re-polymerization of SKL in SCW. The formation of diarylmethane structures was detected in HSQC spectra of solid residue after the SCW process. Lignin released fragments with free phenolic β-O-4 structures, as well as the monomeric product vanillyl alcohol are involved with the formation of o-o´ and o-p ´ diarylmethane structures. Chemical structure of Kraft lignin and its polymeric product after the SCW process was remarkably similar, as shown by HSQC, indicating that re-polymerization reactions occur through cross-linking polymerization, mainly in their fractions of low molecular weight products.

Mechanism of Hydroquinone Oxidation by Hot Plasma Pulsed Radiation

The degradation of hydroquinone in interactions with OH• , HO2 • radicals, nitrous and peroxynitrous acids has been studied. Active species were generated using a corona electric discharge and pulsed radiation from hot plasma of a spark electric discharge. When interacting with hydroxyl radicals, hydroquinone breaks down into low molecular weight products. When interacting with species formed under the action of hot plasma radiation, chain oxidation of hydroquinone to benzoquinone occurs. This process is environmentally friendly and does not require the use of additional catalysts. Products formed under the action of radiation decompose over time.

Pilot study evaluating the therapeutic effects of a new pre-mixed injectable product of low molecular weight (LMW) hyaluronic acid added to six amino acids (HY6AA +Formula) in facial skin aging

Introduction: Skin aging is a complex biological phenomenon, it is the result of an intrinsic decline in cellular functions due to age and genetically programmed, added to a continuous exposure of various harmful external factors that influence its trend. Both mechanisms modify the structure of the extracellular matrix (ECM) by acting on the quantity and composition of its proteins: type III collagen constitutes 50% of the collagen in the dermis of the neonatal skin but only 5% of the collagen in the aging adult skin, type IV collagen, an important component of the basement membrane, forms anchor plates between types of structural collagen, it decreases with age after 35 years affecting the thickness of the epithelial basement membrane significantly. Aims of the study: The Aim of the study was to evaluate the therapeutic effects of a new pre-mixed injectable product of not cross-linked LMW Hyaluronic Acid (50-250 KDaltons) added to a specific mixture of six amino acids ( HY6AA + Formula) to improve the signs of chrono and photo-aging of the skin of the facial area, through a simple and minimally invasive injectable procedure with fast obtaining results. Materials and methods: The open clinical pilot trial was conducted by two centres under medical control. 3,5 ml HY6AA+Formula was performed by injecting 3 times at intervals of 2 weeks each. The Visia device as well as the GAIS (Global Aesthetic Improvement Scale) and VAS scale, the skin elasticity scale and the wrinkle correction scale were used for the assessment. Efficacy evaluations were performed previously to each injection treatment, performed every two week for three times, and 4 weeks after the third injection. Skin elasticity was evaluated by Pinching Test immediately after each treatment and at 4 weeks after the third injection. Conclusions: The photo analysis by Visia device proves the significant effectiveness of HY6AA + Formula. The data recorded on the skin texture improvement, dyschromia and skin elasticity are very encouraging, especially considering the minimal invasiveness of the procedure and the limited number of sessions required. The improvement of skin quality in most cases occur after the first treatment, and as the treatment protocol progresses, patients' feelings and their individual assessment of skin quality also gradually improve.

Microdroplet-Mediated Radical Polymerization.

Micrometer-sized aqueous droplets serve as a unique reactor that drives various chemical reactions not seen in bulk solutions. However, their utilization has been limited to the synthesis of low molecular weight products at low reactant concentrations (nM to μM). Moreover, the nature of chemical reactions occurring outside the droplet remains unknown. This study demonstrated that oil-confined aqueous microdroplets continuously generated hydroxyl radicals near the interface and enabled the synthesis of polymers at high reactant concentrations (mM to M), thus successfully converting the interfacial energy into the synthesis of polymeric materials. The polymerized products maintained the properties of controlled radical polymerization, and a triblock copolymer with tapered interfaces was prepared by the sequential addition of different monomers into the aqueous microdroplets. Furthermore, a polymerization reaction in the continuous oil phase was effectively achieved by the transport of the hydroxyl radicals through the oil/water interface. This interfacial phenomenon is also successfully applied to the chain extension of a hydrophilic polymer with an oil-soluble monomer across the microdroplet interface. Our comprehensive study of radical polymerization using compartmentalization in microdroplets is expected to have important implications for the emerging field of microdroplet chemistry and polymerization in cellular biochemistry without any invasive chemical initiators.

Chitosan Oligosaccharide Inhibits the Synthesis of Milk Fat in Bovine Mammary Epithelial Cells through AMPK-Mediated Downstream Signaling Pathway.

Simple SummaryIn order to study the effect of chitosan oligosaccharides on milk fat synthesis of bovine mammary epithelial cells (BMECs), we did a series of related experiments. The results showed that chitosan oligosaccharide (COS) could inhibit the fatty acid synthesis and promote milk fat decomposition and oxidation through AMPK/SREBP1/SCD1, AMPK/HSL and AMPK/PPARα signaling pathways to reduce the milk fat content in bovine mammary epithelial cells. We elucidated the important role of COS in BMECs lipid metabolism. COS may be the potential small-molecule component in milk cow molecular breeding to regulate milk fat synthesis and metabolism. These findings will help us to further understand the mechanism of COS on milk fat metabolism.Chitosan oligosaccharide (COS) is a variety of oligosaccharides, and it is also the only abundant basic amino oligosaccharide in natural polysaccharides. Chitosan oligosaccharide is a low molecular weight product of chitosan after enzymatic degradation. It has many biological effects, such as lipid-lowering, antioxidant and immune regulation. Previous studies have shown that chitosan oligosaccharide has a certain effect on fat synthesis, but the effect of chitosan oligosaccharide on milk fat synthesis of bovine mammary epithelial cells (BMECs) has not been studied. Therefore, this study aimed to investigate chitosan oligosaccharide’s effect on milk fat synthesis in bovine mammary epithelial cells and explore the underlying mechanism. We treated bovine mammary epithelial cells with different concentrations of chitosan oligosaccharide (0, 100, 150, 200, 400 and 800 μg/mL) for 24 h, 36 h and 48 h respectively. To assess the effect of chitosan oligosaccharide on bovine mammary epithelial cells and determine the concentration and time for chitosan oligosaccharide treatment on cells, several in vitro cellular experiments, including on cell viability, cycle and proliferation were carried out. The results highlighted that chitosan oligosaccharide (100, 150 μg/mL) significantly promoted cell viability, cycle and proliferation, increased intracellular cholesterol content, and reduced intracellular triglyceride and non-esterified fatty acids content. Under the stimulation of chitosan oligosaccharide, the expression of genes downstream of Phosphorylated AMP-activated protein kinase (P-AMPK) and AMP-activated protein kinase (AMPK) signaling pathway changed, increasing the expression of peroxisome proliferator-activated receptor alpha (PPARα) and hormone-sensitive lipase (HSL), but the expression of sterol regulatory element-binding protein 1c (SREBP1) and its downstream target gene stearoyl-CoA desaturase (SCD1) decreased. In conclusion, these results suggest that chitosan oligosaccharide may inhibit milk fat synthesis in bovine mammary epithelial cells by activating the AMP-activated protein kinase signaling pathway, promoting the oxidative decomposition of fatty acids and inhibiting fatty acid synthesis.

New Perspectives into Cellulose Fast Pyrolysis Kinetics Using a Py-GC × GC-FID/MS System.

Cellulose pyrolysis is reportedly influenced by factors such as sample size, crystallinity, or different morphologies. However, there seems to be a lack of understanding of the mechanistic details that explain the observed differences in the pyrolysis yields. This study aims to investigate the influence of particle size and crystallinity of cellulose by performing pyrolysis reactions at temperatures of 673–873 K using a micropyrolyzer apparatus coupled to a GC × GC-FID/TOF-MS and a customized GC-TCD. Over 60 product species have been identified and quantified for the first time, including water. Crystalline cellulose with an average particle size of 30–50 × 10–6 m produced 50–60 wt % levoglucosan. Predominantly amorphous cellulose with an average particle size of 10–20 × 10–6 m resulted in remarkably low yields (10–15 wt %) of levoglucosan complemented by higher yields of water and glycolaldehyde. A detailed kinetic model for cellulose pyrolysis was used to obtain mechanistic insights into the different pyrolysis product compositions. The kinetics of the mid-chain dehydration and fragmentation reactions strongly influence the total yields of low-molecular weight products (LMWPs) and are affected by cellulose chain arrangement. Levoglucosan yields are very sensitive to the activation of parallel cellulose decomposition reactions. This can be attributed to the mid-chain reactions forming smaller chains with the levoglucosan ends, which remain in the solid phase and react further to form LMWPs. Direct quantification of water helped to improve the description of the dehydration, giving further indications of the dominant role of mid-chain reaction pathways in amorphous cellulose pyrolysis.

Polycondensation in a spray of aqueous-alcoholic solution of lactic acid

The removal of low molecular weight products of the reaction and heat withdrawal is one of the problems of bulk polycondensation. Polycondensation under spray conditions is an effective way to solve these problems. Based on the example of the reversible reaction of lactic acid polycondensation, it was shown that size effects can significantly affect the conversion rate, the degree of polymerization, and the rate of processes. Chemical thermodynamics suggests that chemical equilibrium in a spray shifts towards the formation of polylactide. In addition, the recondensation of volatile components (water, lactic acid, solvent) stabilizes the concentration of reagents and the temperature in the spray drops throughout the entire process. Model experiments confirming the obtained regularities are presented. Microscopic observation of sessile drops of aqueous and aqueous-alcoholic lactic acid solutions demonstrated the formation of polylactide under normal conditions (without heating, catalyst, evacuation).

Hydrolytic Depolymerization of Polyethylene Terephthalate by Reactive Extrusion

Abstract Continuous hydrolytic depolymerization of polyethylene terephthalate (PET) resin at high temperature and pressure was carried out in a co-rotating twin screw extruder. In this novel process, hydrolysis is achieved by injection of saturated steam at high pressure. Optimum conditions occur at relatively low screw speeds and water/PET ratios. Hydrolysis extent was measured using carboxyl end group titration, and by determination of molecular weights using NMR and GPC analysis. Low molecular weight products are obtained at low residence times in the extruder, suggesting high depolymerization rates. This is supported by the results of a simple kinetic model.

Эффективный метод полного контроля процессов производства поли--олефиновых масел — лазерная спектроскопия комбинационного рассеяния

The developed approaches to increasing the selectivity of analysis by laser Raman spectroscopy, the use of chemometrics and a proprietary algorithm for self-tuning calibration models with the efficiency and speed of the method have shown a rare andexcellent opportunity for information equivalent on-line control of all technological stages of the production of poly- -olefin oils and other products through a network of fiber-optic probes. The oligomers of -olefins C6, C8 and C10 obtained by the technology of heterogeneous chromium-oxide catalysis developed at RN-RDC, as shown by the Raman spectra, differ from analogues obtained by homogeneous synthesis by a variety of structures of unsaturated groups, as well as by a greater width and variability of molecular mass distribution, which makes it possible to regulate a wide range assortment of low and high molecular weight products. A specialcase - the atypically high sensitivity of Raman spectra to the length of the chain - make it possible in the synthesis process to predict and adjust in real time the molecular weight of oligomers and other target properties, and replacing a fleet of traditional analytical equipment with one method.

Pentamethylcyclopentadienyl Molybdenum(V) Complexes Derived from Iodoanilines: Synthesis, Structure, and ROP of ε-Caprolactone

The reaction of [Mo(η-C5Me5)Cl4] with the ortho-, meta-, or para-iodo-functionalized anilines 2-IC6H4NH2, 3-IC6H4NH2, 4-IC6H4NH2 yields imido or amine products of the type [Mo(η-C5Me5)Cl2(IC6H4N)] (2-I, 1, 3-I, 3, 4-I, 5) or [Mo(η-C5Me5)Cl4(IC6H4NH2)] (3-I, 2, 4-I, 4), respectively, depending on the reaction stoichiometry/conditions; we were unable to isolate an amine complex of the 2-I derivative. The reaction of [Mo(η-C5Me5)Cl4] with one equivalent of 2-I,4-FC6H3NH2 in the presence of Et3N afforded [Mo(η-C5Me5)Cl2(2-I,4-FC6H3N)]·MeCN (6·MeCN), which, upon exposure to air, afforded the Mo(VI) imido complex [Mo(η-C5Me5)Cl3(2-I,4-FC6H3N)] (7). For comparative studies, the structure of the aniline (C6H5NH2)-derived complex [Mo(η-C5Me5)Cl2(2-C6H3N)] (8) has also been prepared. The molecular structures of 1–8 have been determined and reveal packing in the form of zig-zag chains or ladders. The complexes catalyze, in the presence of benzyl alcohol under N2, the ring-opening polymerization (ROP) of ε-caprolactone affording relatively low molecular weight products. The MALDI-ToF spectra indicate that a number of polymer series bearing a variety of end groups are formed. Conducting the ROPs as melts or under air results in the isolation of higher molecular weight products, again bearing a variety of end groups. Kinetic studies reveal the aniline-derived imido complex 8 performs best, whilst a meta-iodo substituent and a Mo(V) centre are also found to be beneficial. The structures of the side products 2-IC6H4NH3Cl and 3-IC6H4NH3Cl are also reported.

Reaction characteristics and mechanisms of sorbitol fast pyrolysis

In the present study, the fast pyrolysis characteristics of sorbitol were deeply explored and the formation mechanism of the main products was revealed using fast pyrolysis experiments and density functional theory (DFT) calculations. The results show that the fast pyrolysis of sorbitol mainly produces low molecular weight products such as hydroxyacetaldehyde (HAA) and hydroxyacetone (HA), furan-based products such as furfural (FF) and 1-(2-furanyl)-ethanone (2-FE), and anhydrosugar product (isosorbitol (IS)). The yield of HA and HAA products is the highest, due to their lower overall energy barriers. Notably, the generation of HA and HAA are simultaneous. The formation of furan-based products 2-FE and FF needs to overcome relatively higher overall energy barriers, despite that some intermediates also appear in the formation of HA and HAA. Hence, the yields of furan-based products are lower than those of low molecular weight products. The reaction intermediates for formation of anhydrosugar IS are different from those of HA/HAA and 2-FE/FF. The overall energy barrier is high that leads to a very low yield of IS. This study provides a theoretical insight into the mechanism research and technique development for selective pyrolysis of sorbitol.

Redox mediator as cathode modifier for enhanced degradation of azo dye in a sequential dual chamber microbial fuel cell-aerobic treatment process

The electron transfer from cathode to azo dye Acid Blue 29 (AB29) using thionine (TH) and anthraquinone-2-sulfonate (AQS) redox mediators were investigated in dual chamber microbial fuel cells (DCMFCs). More than 90% of color was removed using electropolymerized TH (192 h) and AQS (264 h) cathodes. Chemical oxygen demand (COD) removal after anaerobic treatment in cathode chamber of TH-MFC, AQS-MFC and unmodified-MFC were 76.6 ± 1.7, 70.8 ± 2.5 and 18.3 ± 2.9%, respectively, which increased to 85.4 ± 1.5, 79.8 ± 3 and 20.6 ± 2.1%, respectively, after aerobic post treatment. Gas chromatography–mass spectrometry (GC–MS) investigations revealed the formation of aromatic amines in DCMFCs which were further degraded into low molecular-weight products in the aerobic post treatment. Electrochemical impedance spectroscopic (EIS) analysis showed lowest charge transfer resistance of TH-cathode which increased the electrochemical reactions and electron transfer rates. These results indicated that AB29 can be efficiently degraded by utilizing modified cathode based DCMFC-aerobic post treatment process along with bioelectricity generation.

Study of the Nature of the Influence of some Oligophosphonates on the Rheological Properties of High-Density Polyethylene

High molecular weight compounds with organophosphorus backbones are usually obtained by polycondensation of phosphorus-containing monomers, leading, most often, to products of low molecular weight at low yields. This fact is explained [1] by several reasons: a decrease in the reactivity of the second functional group of the monomer after the first one has reacted; the possibility of the formation of cyclic compounds; hydrolytic instability of the phosphorus-heteroatom bond (usually P-O, P-N), etc.

Carrageenan oligosaccharides and associated carrageenan-degrading bacteria induce intestinal inflammation in germ-free mice

Carrageenans (CGNs) are widely used in foods and pharmaceuticals although their safety remains controversial. To investigate the effects of CGNs and CGN-degrading bacteria in the human colon, we screened for CGN degradation by human fecal microbiota, and for inflammatory response to CGNs and/or CGN-degrading bacteria in germ free mice. Thin-layer chromatography indicated that high molecular weight (MW) CGNs (≥100 kDa) remained undegraded in the presence of human fecal microbiota, whereas low MW CGNs, i.e., κ-carrageenan oligosaccharides (KCO, ~4.5 kDa) were degraded when exposed to seven of eight human fecal samples, although sulfate groups were not removed during degradation. Bacteroides xylanisolvens and Escherichia coli isolates from fecal samples apparently degraded KCO synergistically, with B. xylanisolvens serving as the primary degrader. Combined treatment of KCO with KCO-degrading bacteria led to greater pro-inflammatory effects in the colon and rectum of germ-free mice than either KCO or bacteria alone. Similarly, p-p38-, CD3-, and CD79a-positive immune cells were more abundant in combined treatment group mice than in either single treatment group. Our study shows that KCO-degrading bacteria and the low MW products of KCO can promote proinflammatory effects in mice, and represent two key markers for evaluating CGN safety in foods or medicines.

Photochemical (UV–vis/H2O2) degradation of carotenoids: Kinetics and molecular end products

Constraining the formation mechanisms of organic matter that persists in aquatic reservoirs is important for determining the reactivity and fate of carbon and nutrients in these environments. Recent studies have linked dissolved organic matter (DOM) accumulating in the ocean to linear terpenoid structures, and carotenoid degradation products have been proposed as potential precursors. The prevalence of reactive oxygen species in aquatic environments and their potential to be quenched by carotenoids led us to examine radical-assisted photochemical degradation of carotenoids as a potential mechanism for DOM formation and transformation. Experiments were conducted with aggregates of β-carotene, astaxanthin, fucoxanthin and meso-zeaxanthin in THF:H2O under solar light irradiation assisted by hydrogen peroxide (UV–Vis/H2O2). Based on the fine structure of UV–Vis spectra, it was determined that β-carotene and meso-zeaxanthin formed J-type aggregates in experimental solutions, while astaxanthin and fucoxanthin formed H2-type aggregates, consistent with their structural characteristics. All carotenoids degraded under the combined influence of photolysis and OH scavenging, with fucoxanthin exhibiting the fastest degradation kinetics (kPO = 3.69 10−3 s−1) and meso-zeaxanthin the slowest (kPO = 4.37 10−4 s−1). The major degradation products detected by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) were apo-aldehydes and apo-ketones, with the latter tending to accumulate, but epoxidation of the carotenoids also took place, and longer irradiation times resulted in lower molecular weight products. Reaction kinetics and accumulating carotenoid oxidation products identified in this study provide potential formation mechanisms and biomarkers for examining DOM cycling.

Simultaneous anaerobic decolorization/degradation of Reactive Black-5 azo dye and chromium(VI) removal by Bacillus cereus strain MS038EH followed by UV-C/H2O2 post-treatment for detoxification of biotransformed products.

The existence of synthetic dyes and heavy metals in textile wastewater is a serious problem. These compounds should be removed before discharge into the environment by an appropriate method. The present study was conducted for the characterization of efficient multi-functional strain Bacillus cereus MS038EH for the simultaneous removal of Reactive Black-5 and Chromium(VI). Maximum decolorization efficiency of 94.74% was achieved at pH 7, 35°C, and 4% inoculum size for 900mg/L of Reactive Black-5. Also, 94.10% efficiency was observed in the presence of 8g/L of yeast extract as an optimum nitrogen source, while carbon sources had no significant effect on decolorization. It should be pointed out that the decolorization efficiency was decreased from 94 to 64% by increasing NaCl concentrations from 0 to 50g/L, respectively. Bacillus cereus strain MS038EH could decolorize 94.31% of Reactive Black-5 (900mg/L) and remove 87.31% of chromium(VI) (30mg/L) within 36h. Results of Gas chromatography-mass spectrometry and Fourier transform-infrared spectroscopy proved that Reactive Black-5 was cleaved into the lower molecular weight products without any azo bonds. However, the phyto-toxicity analysis showed that Reactive Black-5 was not toxic for Triticum aestivum and Maize, while biologically treated Reactive Black-5 was toxic for seeds. Therefore, ultraviolet-C/H2O2 was applied for the detoxification of biotransformed products. When ultraviolet-C/H2O2 was applied as post-treatment, the seeds were germinated completely. It is demonstrated that the application of ultraviolet-C/H2O2 after anaerobic treatment is effective for toxicity reduction of textile wastewater.

Exploring lignin depolymerization by a bi-enzyme system containing aryl alcohol oxidase and lignin peroxidase in aqueous biocompatible ionic liquids

Enzymatic depolymerization of lignin to produce low molecular weight products requires mild reaction conditions and exhibits higher selectivity compared to thermochemical lignin depolymerization. However, it remains challenging to depolymerize lignin enzymatically, partially due to the low solubility of lignin in aqueous phase. This study aimed to develop a novel approach to combine aqueous lignin extraction with enzymatic lignin depolymerization in biocompatible ionic liquids. A bi-enzyme system containing aryl alcohol oxidase (AAO) and lignin peroxidase (LiP) was developed to depolymerize lignin. Temperature and pH profiles for LiP and AAO were determined. Biocompatibilities of LiP and AAO in different deep eutectic solvents and ionic liquids were investigated. Aqueous cholinium glycinate was found to be an efficient and suitable solvent to solubilize lignin and serve as a biocompatible medium for enzymes to work. LiP and AAO together reduced lignin molecular weight in both solid and liquid phase after enzymatic lignin depolymerization.

Toward an Efficient Process for the Cu(0)‐Mediated Synthesis and Chain Extension of Poly(methyl acrylate) Macroinitiator Using PMDETA as Ligand

AbstractMe6TREN (tris[2‐(dimethylamino)ethyl]amine) is commonly used in Cu(0)‐mediated polymerization of acrylates due to its ability to promote high reaction rates while maintaining excellent control of chain growth. However, its cost presents a significant barrier to commercialization. Thus, the use of PMDETA (N,N,Nʹ,Nʹʹ,Nʹʹ‐pentamethyldiethylenetriamine), a ligand that is significantly less expensive than Me6TREN but is known to reduce the polymerization rate as well as control, is explored. The continuous production of low molecular weight (MW) poly(methyl acrylate) using PMDETA ligand in a copper tubular reactor is demonstrated, with conversions >70% achieved with a residence time of 32 min at 70 °C. The resulting macroinitiator solution can be stored and chain extended with methyl acrylate (MA) to high conversion in a semibatch reactor using either PMDETA or Me6TREN as additional ligand, increasing the versatility of a newly developed process to efficiently produce block copolymers using either ligand, or a combination of the two. First results suggest that the two‐step process can also be used to chain extend the macroinitiator with methacrylates, thus extending the range of materials that can be produced.

Method for the Production of Fat from Raw Materials and Animal Waste

The aim of this article was to study degreasing of raw materials raw fish bone waste and animal waste. A new method was developed, aimed at intensive extraction of fat with an additional absorber- de-limonene, placed in water during high-temperature cooking of raw materials of animal origin. De-limonene is a widespread terpene hydrocarbon, and a primary component of orange peel oil (constitutes up to 80–90%). Degreasing with the inclusion of de-limonene increases the degree of hydrolysis of collagen from animal raw materials, which intensifies the extraction of fat from the processed raw materials. High-temperature cooking promotes the breakdown of triglycerides into free fatty acids, which further break down into low molecular weight products. At the end of the heat the temperature of the heating plates is 70-90 ° C, the pressure inside the boiler is 1.6,-2.4 kPa, the duration is 60-100 minutes treatment of the raw material, a two-phase system was obtained: dry fat greaves and fat. Fat was sucked off by pumps connected to digesters, and greasy greaves were sent for degreasing by pressing. The method produced broth, fat, and feed.

Recent Perspectives for Targeted Therapies

It is well known that targeted therapies have led to a paradigm shift in the treatment of autoimmune/inflammatory diseases such as rheumatoid arthritis. Biologics use intravenous or subcutaneous injection because of their size (90-150 kDa) and target multiple cytokines such as TNF and IL-6, as well as cell surface functioning molecules such as CD28 and CD20. Orally available low-molecular weight products target intracellular signaling molecules, including JAK, BTK, and S1P1. Biologics and JAK inhibitors are novel and have new modes of action that effectively close the unmet medical needs of multiple autoimmune/inflammatory diseases. Furthermore, such targeted therapies have the potential to bring about a paradigm shift in the treatment of immune/inflammatory diseases of the central nervous system.