Prohibitin 2 deficiency in photoreceptors leads to progressive retinal degeneration and facilitated Müller glia engulfing microglia debris.

Müller glia and microglia are capable of phagocytosing fragments of retinal cells in response to retinal injury or degeneration. However, the direct evidence for their mutual interactions between Müller glia and microglia in the progression of retinal degeneration (RD) remains largely unclear. This study aims to construct a progressive RD mouse model and investigate the activated pattern of Müller glia and the interplay between Müller glia and microglia in the early stage or progression of RD. A Prohibitin 2 (Phb2) photoreceptor-specific knockout (RKO) mouse model was generated by crossing Phb2flox/flox mice with Rhodopsin-Cre mice. Optical Coherence Tomography (OCT), histological staining, and Electroretinography (ERG) assessed retinal structure and function, and RKO mice exhibited progressive RD from six weeks of age. In detail, six-week-old RKO mice showed no significant retinal impairment, but severe vision dysfunction and retina thinning were shown in ten-week-old RKO mice. Furthermore, RKO mice were sensitive to Light Damage (LD) and showed severe RD at an early age after light exposure. Bulk retina RNA-seq analysis from six-week-old control (Ctrl) and RKO mice showed reactive retinal glia in RKO mice. The activated pattern of Müller glia and the interplay between Müller glia and microglia was visualized by immunohistology and 3D reconstruction. In six-week-old RKO mice or light-exposed Ctrl mice, Müller glia were initially activated at the edge of the retina. Moreover, in ten-week-old RKO mice or light-exposed six-week-old RKO mice with severe photoreceptor degeneration, abundant Müller glia were activated across the whole retinas. With the progression of RD, phagocytosis of microglia debris by activated Müller glia were remarkably increased. Altogether, our study establishes a Phb2 photoreceptor-specific knockout mouse model, which is a novel mouse model of RD and can well demonstrate the phenotype of progressive RD. We also report that Müller glia in the peripheral retina is more sensitive to the early damage of photoreceptors. Our study provides more direct evidence for Müller glia engulfing microglia debris in the progression of RD due to photoreceptor Phb2 deficiency.

Random Silica-Glass Microlens Arrays Based on the Molding Technology of Photocurable Nanocomposites.

Random microlens arrays (rMLAs) have been widely applied as a beam-shaping component within an optical system. Silica glass is undoubtedly the best choice for rMLAs because of its wide range of spectra with high transmission and high damage threshold. Yet, machining silica glass with user-defined shapes is still challenging. In this work, novel design and fabrication methods of random silica-glass microlens arrays (rSMLAs) are proposed and a detailed investigation of this technology is presented. Based on the molding technology, the fabricated rSMLAs with tunable divergent angles demonstrate superior physical properties with 1.81 nm roughness, 1074.33 HV hardness, and excellent thermal stability at 1250 °C for 3 h. Meanwhile, their characterized optical performance shows a high transmission of over 90% in the ultraviolet spectrum. The fabricated two types of rSMLAs exhibit excellent effects of beam homogenization with surprising energy utilization (more than 90%) and light spot uniformity (more than 80%). This innovative process paves a new route for fabricating rMLAs on solid silica glass and breaking down the barrier of rMLAs to broader applications.

Macular buckling alone versus combined inverted ILM flap on macular hole-associated macular detachment in patients with high myopia.

PURPOSE: To compare the efficacy of macular buckling (MB) alone against a combined internal limiting membrane (ILM) inversion flap for full-thickness macular hole (FTMH)-associated macular detachment (MD) in patients with high myopia. METHODS: This was a prospective interventional case series of patients with high myopia surgically treated with MB alone or combined with an inverted ILM flap for FTMH- associated MD. Best-corrected visual acuity (BCVA) at the 24-month postoperative follow-up, rate of initial retinal reattachment and macular hole closure were measured. RESULTS: A total of 62 eyes from 62 participants (33 in the MB group, 29 in the combination group) were studied. Postoperative BCVA improved significantly in both the combination group (P < 0.001) and the MB group (P = 0.027). The postoperative BCVA at 12 months (P = 0.021) and 24 months (P = 0.041) was significantly better in the combination group than in the MB group. The postoperative BCVA was not significantly different between the eyes with closed and unclosed MH at each follow-up time point (P > 0.05). In the combination group, we observed earlier retinal reattachment and closure of the MH as well as a higher rate of MH closure (82.8% vs. 66.7%) than in the MB group, although this difference was insignificant (P = 0.248). CONCLUSION: MB combined with the ILM flap inversion technique achieved better postoperative BCVA and a higher success rate of MH closure than MB alone. We believe that combination surgery should be preferentially recommended.

Metabolic characterization of human intraocular fluid in patients with pathological myopia.

Pathological myopia (PM) and its associated complications can lead to permanent vision loss. However, the cellular mechanisms underlying PM development remain unclear. To identify the metabolic alterations that may contribute to the pathophysiology of PM, we performed non-targeted metabolomics analysis using ultra-high-performance liquid chromatography with tandem mass spectrometry in age- and sex-matched patients with PM (n = 30) and individuals without myopia as controls (n = 30). Targeted metabolomics and insulin microarray were used to validate the results. We identified 508 metabolites in the aqueous humour (AH) and 601 in the vitreous humour (VH). Statistical evaluation revealed that 104 metabolites in AH and 114 metabolites in VH were significantly different between the two groups (variable important for the projection >1, fold change >1.5, or < 0.667, and P < 0.05). The four metabolic pathways enriched in both AH and VH identified to be associated with PM were: bile secretion, insulin secretion, thyroid hormone synthesis, and cGMP-PKG signaling pathway. The concentration of 10 amino acids was significantly higher in the PM than in the controls. Insulin microarray analysis showed that insulin, insulin-like growth factor 2 (IGF-2), IGF-2R, insulin-like growth factor binding protein 1 (IGFBP-1), IGFBP-2, IGFBP-3, IGFBP-4, and IGFBP-6 levels were significantly higher in PM patients compared to that in the controls. Thus, this study identified potential metabolite biomarkers for PM and provided novel insights into the mechanisms underlying this disorder.

Detailed numerical analysis of the effect of radial column heterogeneities on peak parking experiments with slowly diffusing analytes.

The origin of the peak skewness that can be observed when applying the deconvolution method to isolate the diffusion process from the flow processes for peak parking experiments conducted under conditions of slow radial equilibration and strong trans-column velocity gradients was investigated. Numerical simulations were carried out for a variety of trans-column velocity profiles and a broad range of experimental conditions and system parameters were investigated. Results show that, under the aforementioned conditions, the traditionally employed variance subtraction method displays a consistent error which follows the dynamics of the diffusive relaxation during both the peak parking and the flow steps. It is also found that, under the same conditions, the peak deconvolution method is bound to produce deconvoluted "parking-only" peaks that are strongly asymmetric, despite the perfectly symmetric nature of the pure diffusion process marking this parking step. It is shown that this asymmetry is acquired during the flow step following the parking stop. During this step, parked and non-parked peaks are deformed in different ways, despite being subjected to the same trans-column velocity profile. This different deformation cannot be filtered away with the deconvolution or the variance subtraction method, hence introducing an error. Solutions to alleviate the peak skewness and the variance error consist of parking the peak close to the inlet or the outlet or exiting the parked peak through the column inlet (flow reversal method). Under the considered conditions, these approaches could reduce the error on the measured effective diffusion coefficient up to 87%. Carrying out the variance subtraction or the deconvolution process with a peak that has also been parked for a substantially long parking time instead of using a "no-parking" peak as is customary done, is another option to counter the effect.

Measurement and modelling of the intra-particle diffusion and b-term in reversed-phase liquid chromatography.

In an ongoing effort to better understand the underlying mechanisms of band broadening in particle-packed reversed-phase liquid chromatography columns, new models for intra-particle diffusion, representing an adsorption- and partition-type retention behavior, are proposed. These models assume the mesoporous zone inside the particles is subdivided in four distinct regions: a fraction f1 filled with bulk mobile phase, a fraction f2 enriched in pure organic modifier extending outside the stationary phase layer, a fraction f3 comprising the liquid surrounding the alkyl chains and a fraction f4 consisting of the stationary phase alkyl chains. Intra-particle diffusion is calculated as a residence time weighted average of the diffusion in these different regions. Experimental procedures and models are proposed to determine the volumes of these four regions and applied to three reversed-phase liquid chromatography columns with different pore sizes (80 Å versus 300 Å) and different stationary phase types (C18 versus C8). The newly proposed models are then applied to predict the intra-particle diffusion of butyrophenone across a wide range of retention factors (1 ≤ k" ≤ 40) in each of these columns. These predictions are compared to experimental data that are extracted from the effective diffusion coefficients of butyrophenone obtained via peak parking experiments. It is demonstrated that both adsorption- and partition-type models for intra-particle diffusion model the actual behavior of the test compound well, and require the determination of only one (partition) or two (adsorption) fitting factors: the obstruction to free movement the analytes experience from the alkyl chains in the retained state (partition and adsorption) and in the unretained state (adsorption). Finally, it is demonstrated that the major contributor to the intra-particle diffusion of retained compounds (k" > 2) is the diffusion these analytes undergo when retained in the organic-modifier enriched zone surrounding the alkyl chains (partition model) or when adsorbed onto the alkyl chains (adsorption model), confirming that surface diffusion plays an important role in the mass transfer of retained compounds in reversed-phase liquid chromatography columns.

Experimental investigation of the retention factor dependency of eddy dispersion in packed bed columns and relation to knox's empirical model parameters.

We report on a systematic and comprehensive (0.7 ≤ k'' ≤ 122) experimental study of the effect of the zone retention factor k'' on eddy dispersion (heddy) in packed bed columns for liquid chromatography. The values for heddy are obtained by subtracting rigorously estimated contributions to the total plate height from longitudinal diffusion (hB) and the mobile (hCm) and stationary zone (hCs) mass transfer resistances. For the first time, hCm-values are calculated using an expression for the Sherwood number (Sh) that has been established and validated in the relevant velocity range. Experiments were carried out on both a fully-porous and a core-shell particle column. In both cases, the eddy dispersion systematically decreased with increasing retention factor k'', dropping 0.5 to 0.8 reduced plate height units when going from the lowest to the highest k''. To establish a simple empirical fitting equation that can represent the observed effects, the widely used power law-based Knox model has been extended to express the dependence of its A- and n-parameters on the retention factor.

A Methodology for the Estimation and Modelling of the Obstruction Factor in the Expression for Mesopore Diffusion in Reversed-Phase Liquid Chromatography Particles.

An experimental methodology for the determination of the obstruction factor in the expression for mesopore diffusion in Zorbax Eclipse Plus C18 reversed-phase particles is proposed. The method uses peak parking experiments conducted on particles that were previously stripped of their stationary phase by flushing the column with trifluoroacetic acid at a temperature of 60°C. Further using pure organic solvents as the mobile phase, any potential retention or surface diffusion effect is omitted. To avoid interference between the parked peaks and baseline disturbances typically occurring when switching on and off the flow, peak parking experiments were carried out in a set-up wherein two identical columns were used in parallel. This set-up allowed to maintain the flow through the detector at all times, by redirecting the flow from one column to the other during the peak parking experiments. Several tracer molecules (ionic and deuterated tracers) were compared and it was found that the use of deuterated molecules provides the best possible coverage of the accessible space of the mesopore volume. Interpreting the peak parking responses obtained with these tracers with a model based on the effective medium theory (EMT) subsequently provided an estimate of the value of the mesopore diffusion obstruction factor γmp. Taking the well-established pore hindrance factor F(λ) correction into account, the obtained experimental γmp-values are more in agreement with the tortuous and constricted diffusion paths one can expect in the void space within a structure resembling a monolithic skeleton with tetrahedral connectivity rather than in the void space formed by a packing of nanospheres. This is also more in line with the measured internal porosity values lying around εpz=0.5, whereas a packing of nanospheres would rather correspond to an Îµpz of 0.4. As such, the presented protocol provides a means to infer the internal mesopore structure of reversed-phase particles.

Seasonal Variations in Microtia of Chinese Population.

BACKGROUND: Seasonality of congenital birth defect could help to identify environmental risk factors. Data concerning the seasonality of the prevalence of microtia are little. This article aims to determine whether births of microtia follow a certain pattern. METHODS: Data were obtained from 2669 patients with microtia who were admitted to Second Ear Reconstruction Center of Plastic Surgery Hospital, Chinese Academy of Medical Science from January 2007 to December 2013. The controls consist of all living births from the Obstetric Department of the Haidian Maternal & Child Health Hospital during the same time. Seasonal variations in months of births were analyzed by using χ test. RESULTS: A total of 2669 patients with microtia and 89,273 healthy living newborns were included in this study. Birth time peak of the patients occurred in autumn, especially in November, compared with the nadir in the spring, especially in April (P G 0.05). The birth time peak of male patients occurred in autumn, too, especially in October and November, While the valley occurred in spring (April, too). However, the seasonality in female patients is not so apparent with the peak occurred in the tail of summer and autumn, especially in August, November, and September orderly, while the valley occurred in March. CONCLUSIONS: There is a possible seasonality in birth months and a difference between sexes of patients with microtia in this native Chinese population. This approach could be useful to study the etiology of microtia.

Methodologies to determine b-term coefficients revisited.

The accuracy of the longitudinal diffusion term (b-term) plays a vital role in the study of mass transfer mechanisms in high performance liquid chromatography (HPLC). In this study, three commonly used methodologies (peak parking; fitting of an experimental van Deemter curve; and the so-called dynamic method) for the determination of the b-term constant were investigated in detail. The three methods were compared based on their mutual agreement, the intra- and inter-day variation of the obtained values and the time required to measure them. Whereas the dynamic method was found to be plagued by impractically long waiting times and concomitant baseline variations compromising accurate measurements of the band broadening, the two other methods lead to very similar b-values, i.e., well within the 1% RSD inter-day variation typically marking both methods in the present study. The best way to study the agreement of the peak parking and plate height fitting method is in a plot of h.ν versus ν, providing a much better zoom on the b-term region of the van Deemter curve than the customarily employed h versus ν-curve and hence allowing to identify any anomalous measurement values (usually related to measurements with a long experimentation time). Verifying the mutual agreement between both methods is proposed here as an additional accuracy check of the obtained data.

Assessment of intra-particle diffusion in hydrophilic interaction liquid chromatography and reversed-phase liquid chromatography under conditions of identical packing structure.

A recently developed stripping protocol to completely remove the stationary phase of reversed-phase liquid chromatography (RPLC) columns and turn them into hydrophilic interaction liquid chromatography (HILIC) columns with identical packing characteristics is used to study the underlying mechanisms of intra-particle diffusion in RPLC and HILIC. The protocol is applied to a column with a large geometrical volume (250×4.6mm, 5µm) to avoid extra-column effects and for compounds with a broad range in retention factors (k" from ∼0.6 to 8). Three types of behavior for the intra-particle diffusion (Dpart/Dm) in RPLC versus HILIC can be distinguished: for nearly unretained compounds (k"<0.6), intra-particle diffusion in HILIC is larger than in RPLC; for compounds with intermediate retention behavior (k"∼0.9-1.2), intra-particle diffusion in HILIC and RPLC are similar; and for well retained compounds (k">1.8), intra-particle diffusion in RPLC is larger than in HILIC. To explain these observations, diffusion in the stationary phase (γsDs) and in the stagnant mobile phase in the mesopore zone (γmpDm) are deduced from experimentally determined values of the intra-particle diffusion, using models derived from the Effective Medium Theory. It is demonstrated that the larger intra-particle diffusion obtained for slightly retained compounds under HILIC conditions is caused by the higher mesopore diffusion in HILIC (γmp=0.474 for HILIC versus 0.435 for RPLC), while the larger intra-particle diffusion obtained for strongly retained compounds under RPLC conditions can be related to the much higher stationary phase diffusion in RPLC (γsDs/Dm=0.200 for RPLC versus 0.113 for HILIC).

Allelopathic Effects, Physiological Responses and Phenolic Compounds in Litter Extracts of Juniperus rigidaSieb. et Zucc.

The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter.

Indigenous Uses and Pharmacological Activity of Traditional Medicinal Plants in Mount Taibai, China.

This study was carried out to investigate the indigenous use and pharmacological activity of traditional medicinal plants of Mount Taibai, China. Pharmacological data were collected by conducting informal interviews with local experienced doctors practicing traditional Chinese medicine and via open-ended questionnaires on villagers. We conclude that the residents of Mt. Taibai possess rich pharmacological knowledge. This study may help identify high-value traditional medicinal plant species, promote economic development associated with local medicinal plants, and increase awareness from government departments.

Extensive database of liquid phase diffusion coefficients of some frequently used test molecules in reversed-phase liquid chromatography and hydrophilic interaction liquid chromatography.

Diffusion plays an important role in all aspects of band broadening in chromatography. An accurate knowledge of molecular diffusion coefficients in different mobile phases is therefore crucial in fundamental column performance studies. Correlations available in literature, such as the Wilke-Chang equation, can provide good approximations of molecular diffusion under reversed-phase conditions. However, these correlations have been demonstrated to be less accurate for mobile phases containing a large percentage of acetonitrile, as is the case in hydrophilic interaction liquid chromatography. A database of experimentally measured molecular diffusion coefficients of some 45 polar and apolar compounds that are frequently used as test molecules under hydrophilic interaction liquid chromatography and reversed-phase conditions is therefore presented. Special attention is given to diffusion coefficients of polar compounds obtained in large percentages of acetonitrile (>90%). The effect of the buffer concentration (5-10mM ammonium acetate) on the obtained diffusion coefficients is investigated and is demonstrated to mainly influence the molecular diffusion of charged molecules. Diffusion coefficients are measured using the Taylor-Aris method and hence deduced from the peak broadening of a solute when flowing through a long open tube. The validity of the set-up employed for the measurement of the diffusion coefficients is demonstrated by ruling out the occurrence of longitudinal diffusion, secondary flow interactions and extra-column effects, while it is also shown that radial equilibration in the 15m long capillary is effective.

Evaluation of the Kinetic Performance Differences between Hydrophilic-Interaction Liquid Chromatography and Reversed-Phase Liquid Chromatography under Conditions of Identical Packing Structure.

A protocol using trifluoroacetic acid at a temperature of 60 °C is developed for the adequate removal of the stationary phase of reversed-phase liquid chromatography (RPLC) columns. This procedure allows for studying the same column first under RPLC and subsequently under hydrophilic-interaction liquid chromatography (HILIC) conditions to isolate intrinsic differences between mass transfer properties in HILIC and RPLC from differences in packing quality. The established procedure allows for a complete removal of the stationary phase (confirmed by retention studies and thermogravimetry analyses) while leaving the structure of the packing unaffected (witnessed by an unchanged external porosity and pressure drop). Accurate plate height analysis comparing compounds at the same zone retention factor indicates a significant difference in reduced c-term (typically 40-80% larger under HILIC conditions), despite the columns otherwise being identical. Correcting for the known contributions of longitudinal diffusion (b-term) and mass transfer (cm- and cs-term) to focus on band broadening originating from eddy dispersion, similar strong differences are observed (differences of some h = 0.3 up to 1.2). These findings show that the interior structure and retention mechanism of the particles have a very strong effect on the observed eddy dispersion, a factor typically ascribed to phenomena occurring outside the particles. This also implies that comparing the quality of packings of different particle types is virtually impossible without the availability of a sound model to correct for the intraparticle effect on the observed eddy dispersion.

Development and validation of LC methods for the separation of misoprostol related substances and diastereoisomers.

Misoprostol is a synthetic prostaglandin E1 analogue which is mainly used for prevention and treatment of gastric ulcers, but also for abortion due to its labour inducing effect. Misoprostol exists as a mixture of diastereoisomers (1:1) and has several related impurities owing to its instability at higher temperatures and moisture. A simple and robust reversed phase liquid chromatographic (RPLC) method is described for the separation of the related substances and a normal phase (NP) LC method for the separation of misoprostol diastereoisomers. The RPLC method was performed using an Ascentis Express C18 (150 mm × 4.6 mm, 5 µm) column kept at 35 °C. The mobile phase was a gradient mixture of mobile phase A (ACN-H2O-MeOH, 28:69:3 v/v/v) and mobile phase B (ACN-H2O-MeOH, 47:50:3 v/v/v) eluted at a flow rate of 1.5 mL/min. UV detection was performed at 200 nm. The NPLC method was undertaken by using an XBridge bare silica (150 mm × 2.1 mm, 3.5 µm) column at 35 °C. The mobile phase contained 1-propanol-heptane-TFA (4:96:0.1%, v/v/v), pumped at a flow rate of 0.5 mL/min. UV detection was performed at 205 nm. This LC method can properly separate the two diastereoisomers (Rs > 2) within an analysis time of less than 20 min. Both methods were validated according to the ICH guidelines. Furthermore, these new LC methods have been successfully applied for purity control and diastereoisomers ratio determination of misoprostol bulk drug, tablets and dispersion.

Evaluation and comparison of the kinetic performance of ultra-high performance liquid chromatography and high-performance liquid chromatography columns in hydrophilic interaction and reversed-phase liquid chromatography conditions.

An intrinsic performance comparison is made of the reduction in analysis time that can be obtained when switching from HPLC to UHPLC column formats in HILIC and reversed-phase conditions. A detailed overview of the packing characteristics of both stationary phase types is given first. It is demonstrated that HILIC columns demonstrate higher external porosity values than their reversed-phase counterparts resulting in lower flow resistance values. Column total porosity values determined from the elution time of a small marker molecule are shown to depend strongly on the composition of the mobile phase. To omit errors that might arise from an over- or underestimation of the column void time, all plate height and kinetic plot data are therefore expressed as a function of the interstitial velocity. Although only a limited number of columns are evaluated in this study, it is shown that the column efficiency of the HILIC columns is lower than that of their reversed-phase counterparts, at least for the compounds evaluated here. Despite this lower efficiency, the kinetic performance of both stationary phase types is similar, due to the much lower viscosity of the mobile phases typically used in HILIC conditions. Finally, it is demonstrated that a similar, yet slightly larger reduction in analysis time can be obtained when switching from HPLC column formats to UHPLC formats in HILIC compared to reversed-phase conditions.

Hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics.

This paper presents a general overview of the application of hydrophilic interaction chromatography (HILIC) in the analysis of antibiotics in different sample matrices including pharmaceutical, plasma, serum, fermentation broths, environmental water, animal origin, plant origin, etc. Specific applications of HILIC for analysis of aminoglycosides, ß-lactams, tetracyclines and other antibiotics are reviewed. HILIC can be used as a valuable alternative LC mode for separating small polar compounds. Polar samples usually show good solubility in the mobile phase containing some water used in HILIC, which overcomes the drawbacks of the poor solubility often encountered in normal phase LC. HILIC is suitable for analyzing compounds in complex systems that elute near the void in reversed-phase chromatography. Ion-pair reagents are not required in HILIC which makes it convenient to couple with MS hence its increased popularity in recent years. In this review, the retention mechanism in HILIC is briefly discussed and a list of important applications is provided including main experimental conditions and a brief summary of the results. The references provide a comprehensive overview and insight into the application of HILIC in antibiotics analysis.

Bis[tetra-aqua-(1,10-phenanthroline-κN,N')cobalt(II)] hexa-aqua-cobalt(II) bis-[3,5-bis-(carboxyl-atometh-oxy)benzoate] tetra-hydrate.

The title compound, [Co(C(12)H(8)N(2))(H(2)O)(4)](2)[Co(H(2)O)(6)](C(11)H(7)O(8))(2)·4H(2)O, was obtanied by the reaction of cobalt acetate with 3,5-bis-(carb-oxy-meth-oxy)benzoic acid and 1,10-phenanthroline. The asymmetric unit contains one tetra-aqua-(1,10-phenanthroline)cobalt(II) cation, one half of a hexa-aqua-cobalt(II) cation that is completed by inversion symmetry, one 3,5-bis-(carboxyl-atometh-oxy)benzoate trianion and two lattice water mol-ecules. The two Co(II) atoms each show a slightly distorted octa-hedral coordination (CoO(6) and CoO(4)N(2)). The cations, anions and lattice water mol-ecules are linked by an intricate network of O-H⋯O hydrogen bonds into a three-dimensional structure.