Preparation and Evaluation of Berberine-Excipient Complexes in Enhancing the Dissolution Rate of Berberine Incorporated into Pellet Formulations.

Berberine is used in the treatment of metabolic syndrome and its low solubility and very poor oral bioavailability of berberine was one of the primary hurdles for its market approval. This study aimed to improve the solubility and bioavailability of berberine by preparing pellet formulations containing drug-excipient complex (obtained by solid dispersion). Berberine-excipient solid dispersion complexes were obtained with different ratios by the solvent evaporation method. The maximum saturation solubility test was performed as a key factor for choosing the optimal complex for the drug-excipient. The properties of these complexes were investigated by FTIR, DSC, XRD and dissolution tests. The obtained pellets were evaluated and compared in terms of pelletization efficiency, particle size, mechanical strength, sphericity and drug release profile in simulated media of gastric and intestine. Solid-state analysis showed complex formation between the drug and excipients used in solid dispersion. The optimal berberine-phospholipid complex showed a 2-fold increase and the optimal berberine-gelucire and berberine-citric acid complexes showed more than a 3-fold increase in the solubility of berberine compared to pure berberine powder. The evaluation of pellets from each of the optimal complexes showed that the rate and amount of drug released from all pellet formulations in the simulated gastric medium were significantly lower than in the intestine medium. The results of this study showed that the use of berberine-citric acid or berberine-gelucire complex could be considered a promising technique to increase the saturation solubility and improve the release characteristics of berberine from the pellet formulation.

Construction of organ of Corti organoid to study the effects of berberine sulfate on damaged auditory cells.

Sensorineural hearing loss (SNHL) is mainly caused by injury or loss of hair cells (HCs) and associated spiral ganglion neurons (SGNs) in the inner ear. At present, there is still no effective treatment for SNHL in clinic. Recently, advances in organoid bring a promising prospect for research and treatment of SNHL. Meanwhile, three-dimensional (3D) printing provides a tremendous opportunity to construct versatile organoids for tissue engineering and regenerative medicine. In this study, gelatin (Gel), sodium alginate (SA), and polyvinyl alcohol (PVA) were used to fabricate biomimetic scaffold through 3D printing. The organ of Corti derived from neonatal mice inner ear was seeded on the PVA/Gel/SA scaffold to construct organ of Corti organoid. Then, the organ of Corti organoid was used to study the potential protective effects of berberine sulfate on neomycin-juried auditory HCs and SGNs. The results showed that the PVA/Gel/SA biomimetic 3D scaffolds had good cytocompatibilities and mechanical properties. The constructed organoid could maintain organ of Corti activity well in vitro. In addition, the injury intervention results showed that berberine sulfate could significantly inhibit neomycin-induced HC and SGN damage. This study suggests that the fabricated organoid is highly biomimetic to the organ of Corti, which may provide an effective model for drug development, cell and gene therapy for SNHL.

Supersaturated Drug Delivery System of Oxyberberine Based on Cyclodextrin Nanoaggregates: Preparation, Characterization, and in vivo Application.

Propose: Oxyberberine (OBB), one of the main metabolites of berberine derived from intestinal and erythrocyte metabolism, exhibits appreciable anti-hyperuricemic activity. However, the low water solubility and poor plasma concentration-effect relationship of OBB hamper its development and utilization. Therefore, an OBB-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) supersaturated drug delivery system (SDDS) was prepared and characterized in this work. Methods: OBB-HP-ß-CD SDDS was prepared using the ultrasonic-solvent evaporation method and characterized. Additionally, the in vitro and in vivo release experiments were conducted to assess the release kinetics of OBB-HP-ß-CD SDDS. Subsequently, the therapeutic efficacy of OBB-HP-ß-CD SDDS on hyperuricemia (HUA) was investigated by means of histopathological examination and evaluation of relevant biomarkers. Results: The results of FT-IR, DSC, PXRD, NMR and molecular modeling showed that the crystallized form of OBB was transformed into an amorphous OBB-HP-ß-CD complex. Dynamic light scattering indicated that this system was relatively stable and maintained by formation of nanoaggregates with an average diameter of 23 nm. The dissolution rate of OBB-HP-ß-CD SDDS was about 5 times higher than that of OBB raw material. Furthermore, the AUC0-t of OBB-HP-ß-CD SDDS (10.882 µg/mL*h) was significantly higher than that of the raw OBB counterpart (0.701 µg/mL*h). The oral relative bioavailability of OBB-HP-ß-CD SDDS was also enhanced by 16 times compared to that of the raw material. Finally, in vivo pharmacodynamic assay showed the anti-hyperuricemic potency of OBB-HP-ß-CD SDDS was approximately 5-10 times higher than that of OBB raw material. Conclusion: Based on our findings above, OBB-HP-ß-CD SDDS proved to be an excellent drug delivery system for increasing the solubility, dissolution, bioavailability, and anti-hyperuricemic potency of OBB.

Enhancing hepatoprotective action: oxyberberine amorphous solid dispersion system targeting TLR4.

Oxyberberine (OBB) is a significant natural compound, with excellent hepatoprotective properties. However, the poor water solubility of OBB hinders its release and absorption thus resulting in low bioavailability. To overcome these drawbacks of OBB, amorphous spray-dried powders (ASDs) of OBB were formulated. The dissolution, characterizations, and pharmacokinetics of OBB-ASDs formulation were investigated, and its hepatoprotective action was disquisitive in the D-GalN/LPS-induced acute liver injury (ALI) mouse model. The characterizations of OBB-ASDs indicated that the crystalline form of OBB active pharmaceutical ingredients (API) was changed into an amorphous form in OBB-ASDs. More importantly, OBB-ASDs showed a higher bioavailability than OBB API. In addition, OBB-ASDs treatment restored abnormal histopathological changes, improved liver functions, and relieved hepatic inflammatory mediators and oxidative stress in ALI mice. The spray drying techniques produced an amorphous form of OBB, which could significantly enhance the bioavailability and exhibit excellent hepatoprotective effects, indicating that the OBB-ASDs can exhibit further potential in hepatoprotective drug delivery systems. Our results provide guidance for improving the bioavailability and pharmacological activities of other compounds, especially insoluble natural compounds. Meanwhile, the successful development of OBB-ASDs could shed new light on the research process of poorly soluble medicine.

Amphiphilic hydroxyethyl starch-based nanoparticles carrying linoleic acid modified berberine inhibit the expression of krasv12 oncogene in zebrafish.

Cancer is one of the most lethal diseases all over the world. Despite that many drugs have been developed for cancer therapy, they still suffer from various limitations including poor treating efficacy, toxicity to normal human cells, and the emergence of multidrug resistance. In this study, the amphiphilic LHES polymers were prepared using hydroxyethyl starch (HES) and linoleic acid as starting materials. The content and substitution degree of linoleic acid groups in LHES polymers were analyzed. The LHES polymers were used for fabricating LHES-B nanoparticles carrying a linoleic acid modified berberine derivative (L-BBR). The LHES-B nanoparticles showed high drug loading efficiency (29%) and could quickly release L-BBR under acidic pH condition (pH = 4.5). Biological investigations revealed that LHES-B nanoparticles significantly inhibited the proliferation of HepG2 cells and exhibited higher cytotoxicity than L-BBR. In a transgenic Tg(fabp10:rtTA2s-M2; TRE2:EGFP-krasv12) zebrafish model, LHES-B nanoparticles obviously inhibited the expression of krasv12 oncogene. These results indicated that LHES carriers could improve the anticancer activity of L-BBR, and the synthesized LHES-B nanoparticles showed great potential as anticancer drug.

Development of dual-channel starch-based film incorporated with betanin@ß-cyclodextrin inclusion complex and berberine for indicating shrimp freshness.

In this study, the ß-cyclodextrin encapsulated betanin (BET@ß-CD) with improved thermal stability and retention as well as the berberine (BBR) with aggregate induced luminescence effect were incorporated into corn amylose (CA) biomatrix to develop colorimetric/fluorescent dual-channel smart film. Results shown that the added functional components were uniformly distributed in the film matrix. The high tensile strength (78.87%), low water solubility (31.15%) and water vapor permeability (1.24 × 10-10 g Pa-1 s-1 m-1) of the film predicted its acceptable stability. It was worth mentioning that the film displayed excellent responsiveness to volatile ammonia (0.025-25 mg/mL) with at least 4 times recyclability. Application experiment demonstrated that the film can achieve macroscopic dynamic monitoring of the freshness of shrimps stored at 25 °C, 4 °C, -20 °C under daylight (red to yellow) and UV light (yellow-green to blue-green). Thus, the study suggests an attractive and effective strategy for constructing dual-mode smart packaging materials for food freshness detection.

C9-Aryl-substituted berberine derivatives with tunable AIE properties for cell imaging application.

Berberine (BBR), a widely used isoquinoline alkaloid derived from natural sources, exhibits aggregation-induced emission (AIE) characteristics and has biological applications such as in selective lipid droplet imaging and photodynamic therapy. However, natural BBR suffers from low fluorescence quantum yield (ΦF) and monotonous emission wavelength. In this paper, a series of C9-position-aryl-substituted berberine derivatives with a D-A structure were designed and synthesized. The electronic effect of the substitution groups can tune the intramolecular charge transfer (ICT) effect of the berberine derivatives, resulting in bluish green to NIR (508-682 nm) luminescence with AIE characteristics and enhanced ΦF up to 36% in the solid state. Interestingly, berberine derivatives containing an amino or a pyridyl group can exhibit fluorescence response to TFA. Cell imaging of the berberine derivatives was conducted using Caco-2 cancer cells, demonstrating their multi-color and efficient wash-free imaging capabilities. This work presents a new strategy for developing novel berberine derivatives with tunable AIE properties for application in biological imaging.

Exosomes derived from mesenchymal stem cells containing berberine for ulcerative colitis therapy.

Berberine (Ber), an isoquinoline alkaloid, is a potential drug therapy for ulcerative colitis (UC) because of its anti-inflammatory activity, high biological safety, and few side effects. Nevertheless, its clinical application is hindered by its limited water solubility and low bioavailability. Currently, compared to synthetic nanocarriers, exosomes as carriers possess advantages such as low toxicity, high stability, and high specificity. Human placental mesenchymal stem cell-derived exosomes (HplMSC-Exos) have emerged as a promising drug delivery system, offering intrinsic anti-inflammatory and antioxidant activities. Therefore, we engineered MSC-Exos loaded with Ber (Exos-Ber) to enhance the solubility and bioavailability of Ber and for colon targeting, revealing a novel approach for treating UC with natural compounds. Structurally and functionally, Exos-Ber closely resembled unmodified Exos. Both in vitro and in vivo investigations confirmed the antioxidant and anti-inflammatory properties of Exos-Ber. Notably, Exos-Ber exhibited reparative effects on injured epithelial cells and reduced cellular apoptosis. Furthermore, Exos-Ber concurrently demonstrated anti-inflammatory and antioxidant activities, contributing to the mitigation of UC, possibly through its modulation of the MAPK signaling pathway. Overall, our findings demonstrate the potential of Exos-Ber as a promising therapeutic option for alleviating UC, highlighting its capacity to enhance the clinical applicability of Ber.

Bletilla striata Polysaccharide-/Chitosan-Based Self-Healing Hydrogel with Enhanced Photothermal Effect for Rapid Healing of Diabetic Infected Wounds via the Regulation of Microenvironment.

The management of diabetic ulcers poses a significant challenge worldwide, and persistent hyperglycemia makes patients susceptible to bacterial infections. Unfortunately, the overuse of antibiotics may lead to drug resistance and prolonged infections, contributing to chronic inflammation and hindering the healing process. To address these issues, a photothermal therapy technique was incorporated in the preparation of wound dressings. This innovative solution involved the formulation of a self-healing and injectable hydrogel matrix based on the Schiff base structure formed between the oxidized Bletilla striata polysaccharide (BSP) and hydroxypropyltrimethylammonium chloride chitosan. Furthermore, the introduction of CuO nanoparticles encapsulated in polydopamine imparted excellent photothermal properties to the hydrogel, which promoted the release of berberine (BER) loaded on the nanoparticles and boosted the antibacterial performance. In addition to providing a reliable physical protection to the wound, the developed hydrogel, which integrated the herbal components of BSP and BER, effectively accelerated wound closure via microenvironment regulation, including alleviated inflammatory reaction, stimulated re-epithelialization, and reduced oxidative stress based on the promising results from cell and animal experiments. These impressive outcomes highlighted their clinical potential in safeguarding the wound against bacterial intrusion and managing diabetic ulcers.

Berberine and chlorogenic acid-assembled nanoparticles for highly efficient inhibition of multidrug-resistant Staphylococcus aureus.

Due to the bacteria resistant to various first-line antibiotics, it is urgent to develop efficient antibiotic alternatives and formulate multidimensional strategies. Herein, supramolecular Chinese medicine nanoparticles are synthesized by self-assembly of berberine (BBR) and chlorogenic acid (CGA), which exhibit higher inhibitory effect against Staphylococcus aureus and multidrug-resistant Staphylococcus aureus (MRSA) than ampicillin, oxacillin, BBR, CGA, as well as mixture of BBR and CGA (minimum inhibitory concentration, MIC = 1.5 µM). The inhibition by BBR/CGA nanoparticles (2.5 µM) reaches 99.06 % for MRSA, which is significantly higher than ampicillin (29.03 %). The nanoparticles with 1/2 MIC can also synergistically restore the antimicrobial activity of ampicillin against MRSA. Moreover, in vivo therapeutic outcome in the murine skin wound infection model suggests that the nanoparticles are able to promote wound healing. This study provides new insights in the application of Chinese medicines self-assembly for MRSA inhibition, as well as solutions for potential persistent clinical infections and drug deficiencies.

The study on synthesis and vitro hypolipidemic activity of novel berberine derivatives nitric oxide donors.

Berberine was used as the lead compound in the present study to design and synthesize novel berberine derivatives by splicing bromine bridges of different berberine carbon chain lengths coupled nitric oxide donors, and their lipid lowering activities were assessed in a variety of ways. This experiment synthesized 17 new berberine nitric oxide donor derivatives. Compared with berberine hydrochloride, most of the compounds exhibited certain glycerate inhibitory activity, and compounds 6a, 6b, 6d, 12b and 12d showed higher inhibitory activity than berberine, with 6a, 6b and 6d having significant inhibitory activity. In addition, compound 6a linked to furazolidone nitric oxide donor showed better NO release in experiments; In further mechanistic studies, we screened and got two proteins, PCSK9 and ACLY, and docked two proteins with 17 compounds, and found that most of the compounds bound better with ATP citrate lyase (ACLY), among which there may be a strong interaction between compound 6a and ACLY, and the interaction force was better than the target drug Bempedoic Acid, which meaning that 6a may exert hypolipidemic effects by inhibiting ACLY; moreover, we also found that 6a may had the better performance in gastrointestinal absorption, blood-brain barrier permeability, Egan, Muegge class drug principle model calculation and bioavailability.

Bone-Targeted Supramolecular Nanoagonist Assembled by Accurate Ratiometric Herbal-Derived Therapeutics for Osteoporosis Reversal.

Developing novel strategies for defeating osteoporosis has become a world-wide challenge with the aging of the population. In this work, novel supramolecular nanoagonists (NAs), constructed from alkaloids and phenolic acids, emerge as a carrier-free nanotherapy for efficacious osteoporosis treatment. These precision nanoagonists are formed through the self-assembly of berberine (BER) and chlorogenic acid (CGA), utilizing noncovalent electrostatic, π-π, and hydrophobic interactions. This assembly results in a 100% drug loading capacity and stable nanostructure. Furthermore, the resulting weights and proportions of CGA and BER within the NAs are meticulously controlled with strong consistency when the CGA/BER assembly feed ratio is altered from 1:1 to 1:4. As anticipated, our NAs themselves could passively target osteoporotic bone tissues following prolonged blood circulation, modulate Wnt signaling, regulate osteogenic differentiation, and ameliorate bone loss in ovariectomy-induced osteoporotic mice. We hope this work will open a new strategy to design efficient herbal-derived Wnt NAs for dealing with intractable osteoporosis.

Nanodiamond-based berberine aquasomes for enhancing penetration across epidermis to treat psoriasis.

The use of berberine hydrochloride (BCS class III) has limited application in psoriasis, when given as topical drug delivery systems, due to low permeability in the skin layer. Hence, berberine hydrochloride-loaded aquasome nanocarriers were developed for skin targeting, particularly epidermis (primary site of psoriasis pathophysiology) and enhance the skin permeability of berberine hydrochloride. Aquasomes were formulated using the adsorption method and characterized by structural morphology TEM, % drug adsorption, drug release profile (in-vitro and ex-vivo), in-vivo efficacy study and stability study. The reduced particle size and higher surface charge of SKF3 formulation (263.57 ± 27.78 nm and -21.0 ± 0.43 mV) showed improved stability of aquasomes because of the development of higher surface resistance to formation of aggregates. The adsorption of hydrophilic berberine and the non-lipidic nature of aquasomes resulted in % adsorption efficiency (%AE) of 94.46 ± 0.39 %. The controlled first-order release behavior of aquasomes was reported to be 52.647 ± 14.63 and 32.08 ± 12.78 % in in-vitro and ex-vivo studies, respectively. In-vivo studies demonstrated that topical application of berberine hydrochloride loaded aquasomes significantly alleviated psoriasis symptoms like hyperkeratosis, scaling and inflammation, due to the reduction in the inflammatory cytokines (IL-17 and IL-23). Therefore, aquasome formulation exhibits an innovative approach for targeted application of berberine hydrochloride in the management of psoriasis.

Lipids Extracted from Mycobacterial Membrane and Enveloped PLGA Nanoparticles for Encapsulating Antibacterial Drugs Elicit Synergistic Antimicrobial Response against Mycobacteria.

Tuberculosis (TB) is a chronic disease caused byMycobacterium tuberculosis (Mtb), which shows a long treatment cycle often leads to drug resistance, making treatment more difficult. Immunogens present in the pathogen's cell membrane can stimulate endogenous immune responses. Therefore, an effective lipid-based vaccine or drug delivery vehicle formulated from the pathogen's cell membrane can improve treatment outcomes. Herein, we extracted and characterized lipids fromMycobacterium smegmatis, and the extracts contained lipids belonging to numerous lipid classes and compounds typically found associated with mycobacteria. The extracted lipids were used to formulate biomimetic lipid reconstituted nanoparticles (LrNs) and LrNs-coated poly(lactic-co-glycolic acid) nanoparticles (PLGA-LrNs). Physiochemical characterization and results of morphology suggested that PLGA-LrNs exhibited enhanced stability compared with LrNs. And both of these two types of nanoparticles inhibited the growth of M. smegmatis. After loading different drugs, PLGA-LrNs containing berberine or coptisine strongly and synergistically prevented the growth of M. smegmatis. Altogether, the bacterial membrane lipids we extracted with antibacterial activity can be used as nanocarrier coating for synergistic antibacterial treatment of M. smegmatis─an alternative model of Mtb, which is expected as a novel therapeutic system for TB treatment.

Compound-compound interaction analysis of baicalin and berberine derivatives in aqueous solution.

Baicalin and berberine are biologically active constituents of the crude drugs Scutellaria root and Coptis rhizome/Phellodendron bark, respectively. Baicalin and berberine are reported to combine together as a 1:1 complex that forms yellow precipitates by electrostatic interaction in decoctions of Kampo formulae containing these crude drugs. However, the structural basis and mechanism for the precipitate formation of this compound-compound interaction in aqueous solution remains unclarified. Herein, we searched for berberine derivatives in the Coptis rhizome that interact with baicalin and identified the chemical structures involved in the precipitation formation. Precipitation assays showed that baicalin formed precipitates with berberine and coptisine but not with palmatine and epiberberine. Thus, the 2,3-methylenedioxy structure may be crucial to the formation of the precipitates, and electrostatic interaction is necessary but is not sufficient. In this multicomponent system experiment, palmatine formed a dissociable complex with baicalin and may competitively inhibit the formation of berberine and coptisine precipitation with baicalin. Therefore, the precipitation formed by berberine and baicalin was considered to be caused by the aggregation of the berberine-baicalin complex, and the 2,3-methylenedioxy structure is likely crucial to the aggregation of the complex.

Screening of Chelidonium majus isoquinoline alkaloids reveals berberine and chelidonine as selective ligands for the nuclear receptors RORß and HNF4α, respectively.

The nuclear receptors hepatocyte nuclear factor 4α (HNF4α) and retinoic acid receptor-related orphan receptor-ß (RORß) are ligand-regulated transcription factors and potential drug targets for metabolic disorders. However, there is a lack of small molecular, selective ligands to explore the therapeutic potential in further detail. Here, we report the discovery of greater celandine (Chelidonium majus) isoquinoline alkaloids as nuclear receptor modulators: Berberine is a selective RORß inverse agonist and modulated target genes involved in the circadian clock, photoreceptor cell development, and neuronal function. The structurally related chelidonine was identified as a ligand for the constitutively active HNF4α receptor, with nanomolar potency in a cellular reporter gene assay. In human liver cancer cells naturally expressing high levels of HNF4α, chelidonine acted as an inverse agonist and downregulated genes associated with gluconeogenesis and drug metabolism. Both berberine and chelidonine are promising tool compounds to further investigate their target nuclear receptors and for drug discovery.

Inhibition of inflammation by berberine: Molecular mechanism and network pharmacology analysis.

BACKGROUND: Traditional Chinese Medicine (TCM), renowned for its holistic approach with a 2000-year history of utilizing natural remedies, offers unique advantages in disease prevention and treatment. Berberine, found in various Chinese herbs, has been employed for many years, primarily for addressing conditions such as diarrhea and dysentery. Berberine has recently become a research focus owing to its pharmacological activities and benefits to human bodies. However, little is known about the anti-inflammatory mechanism of berberine. PURPOSE: To summarize recent findings regarding the pharmacological effects and mechanisms of berberine anti-inflammation and highlight and predict the potential therapeutic effects and systematic mechanism of berberine. METHODS: Recent studies (2013-2023) on the pharmacological effects and mechanisms of berberine anti-inflammation were retrieved from Web of Science, PubMed, Google Scholar, and Scopus up to July 2023 using relevant keywords. Network pharmacology and bioinformatics analysis were employed to predict the therapeutic effects and mechanisms of berberine against potential diseases. RESULTS: The related pharmacological mechanisms of berberine anti-inflammation include the inhibition of inflammatory cytokine production (e.g., IL-1ß, IL-6, TNF-α), thereby attenuating the inflammatory response; Inhibiting the activation of NF-κB signaling pathway and IκBα degradation; Inhibiting the activation of MAPK signaling pathway; Enhancing the activation of the STAT1 signaling pathway; Berberine interacts directly with cell membranes through a variety of pathways, thereby influencing cellular physiological activities. Berberine enhances human immunity and modulates immune system function, which is integral to addressing certain autoimmune and tumour-related health concerns. CONCLUSION: This study expounds on the correlation between berberine and inflammatory diseases, encapsulating the mechanisms through which berberine treats select typical inflammatory ailments. Furthermore, it delves into a deeper understanding of berberine's effectiveness by integrating network pharmacology and molecular docking techniques in the context of treating inflammatory diseases. It provides guidance and reference for berberine's subsequent revelation of the modern scientific connotation of Chinese medicine.

Berberine: Pharmacological Features in Health, Disease and Aging.

BACKGROUND: Berberine is the main active compound of different herbs and is defined as an isoquinoline quaternary botanical alkaloid found in barks and roots of numerous plants. It exhibits a wide range of pharmacological effects, such as anti-obesity and antidiabetic effects. Berberine has antibacterial activity against a variety of microbiota, including many bacterial species, protozoa, plasmodia, fungi, and trypanosomes. OBJECTIVE: This review describes the role of berberine and its metabolic effects. It also discusses how it plays a role in glucose metabolism, fat metabolism, weight loss, how it modulates the gut microbiota, and what are its antimicrobial properties along with its potential side effects with maximal tolerable dosage. METHODS: Representative studies were considered and analyzed from different scientific databases, including PubMed and Web of Science, for the years 1982-2022. RESULTS: Literature analysis shows that berberine affects many biochemical and pharmacological pathways that theoretically yield a positive effect on health and disease. Berberine exhibits neuroprotective properties in various neurodegenerative and neuropsychological ailments. Despite its low bioavailability after oral administration, berberine is a promising tool for several disorders. A possible hypothesis would be the modulation of the gut microbiome. While the evidence concerning the aging process in humans is more limited, preliminary studies have shown positive effects in several models. CONCLUSION: Berberine could serve as a potential candidate for the treatment of several diseases. Previous literature has provided a basis for scientists to establish clinical trials in humans. However, for obesity, the evidence appears to be sufficient for hands-on use.

Fluorimetric Cell Analysis with 9-Aryl-Substituted Berberine Derivatives as DNA-Targeting Fluorescent Probes.

DNA-sensitive fluorescent light-up probes based on berberine are presented. This biogenic fluorophore was chosen as central unit to use its potential biocompatibility and its DNA-binding properties. To provide predictable fluorescence quenching in aqueous solution and a fluorescence light-up effect upon DNA binding, aryl substituents were attached at the 9-position by Suzuki-Miyaura coupling reactions. The 9-arylberberine derivatives have a very low fluorescence quantum yield (Φfl =<0.02), which is caused by the radiationless deactivation of the excited state by torsional relaxation about the biaryl axis. In addition, these berberine derivatives intercalate into DNA with high affinity (Kb =2.0-22×104  M-1 ). Except for the nitrophenyl- and hydroxyphenyl-substituted derivatives, all tested compounds exhibited a pronounced fluorescence light-up effect upon association with DNA, because the deactivation of the excited-state by torsional relaxation is suppressed in the DNA binding site. Most notably, it was shown exemplarily with the 9-(4-methoxyphenyl)- and the 9-(6-methoxynaphthyl)-substituted derivatives that these properties are suited for fluorimetric cell analysis. In particular, these probes generated distinct staining patterns in eukaryotic cells (NIH 3T3 mouse fibroblasts), which enabled the identification of nuclear substructures, most likely heterochromatin or nucleoli, respectively.

The interaction on HSA and the antibacterial activity from four polyoxometalate hybrids based on berberine.

Four organic-polyoxometalate hybrids BR4[SiW12O40] (BR-SiW), BR3[PMo12O40] (BR-PMo), BR4K[EuSiW11O40]·2H2O (BR-EuSiW) and BR6Na3[EuW10O36] (BR-EuW) were fabricated by the polyoxometalates (POMs) anions and berberine cations (BR) noted for the alkaloids in traditional Chinese herbal medicine. These hybrids have been characterized and confirmed. The interaction between hybrids and human serum albumin (HSA) was investigated in a buffer solution (pH 7.4) using ultraviolet-visible light absorption and fluorescence techniques. The classical Stern-Volmer equation was used to analyze the fluorescence quenching at three temperatures (296, 303 and 310 K), and the static quenching mechanism for interaction was proposed. The Thermodynamic parameters, enthalpy, entropy change, and Gibbs free energy of hybrids interacting on HSA were calculated by Scatchard equation. The results indicated that therewas one binding site on the protein and BR-POMs all showed stronger binding force than that of raw materials. Synchronous fluorescence results showed that the binding sites of BR-POMs and HSA were not effectively affected the surrounding microenvironment. The following antibacterial experiments implied that inhibitory effect of hybrids were synergistic effect from organic active ingredient and POMs but the simple combination. All these data were prepared for further research on biology.