Investigation of Hydration States of Ionic Liquids by Fourier Transform Infrared Absorption Spectroscopy: Relevance to Stabilization of Protein Molecules.

Among many kinds of ionic liquids, some hydrated ionic liquids (Hy ILs) have shown an exceptional capability to stabilize protein molecules and maintain their structure and functions over a long period. However, the complex IL-water interaction among these protein-stabilizing Hy ILs has yet to be elucidated clearly. In this work, we investigate the origin of the compatibility of ionic liquid with proteins from the viewpoint of hydration structure. We systematically analyzed the hydrogen-bonding state of water molecules around ionic liquid using Fourier transform infrared absorption (FT-IR) spectroscopy. We found that the native hydrogen-bonding network of water remained relatively unperturbed in the protein-stabilizing ILs. We also observed that the protein-stabilizing ILs have a strong electric field interaction with the surrounding water molecules and this water-IL interaction did not disrupt the water-water hydrogen-bonding interaction. On the other hand, protein-denaturing ILs perturb the hydrogen-bonding network of the water molecules to a greater extent. Furthermore, the protein-denaturing ILs were found to have a weak electric field effect on the water molecules. We speculate that the direct hydrogen bonding of the ILs with water molecules and the strong electric field of the ions lasting several hydration shells while maintaining the relatively unperturbed hydrogen-bonding network of the water molecules play an essential role in protein stabilization.

Hydrated Ionic Liquids: Perspective for Bioscience.

Hydrated ionic liquid (IL) is a simple mixture of IL and water. Unique aqueous electrolyte solution can be designed by mixing IL with limited amount of water. In most hydrated ILs, there are no free water and all are strongly interacted with ions. The properties of hydrated ILs, such as polarity, viscosity, ion mobility, and hydrogen bonding ability, can therefore be controlled simply by water content. This mixture is expected to provide similar environment to that of living cell, and is desired to be effective solvents for biomolecules. In this account, we would like to survey the basic properties, recent results, and future aspects of the hydrated ILs.

Nonconvulsive Seizure Detection by Reduced-Lead Electroencephalography in Children with Altered Mental Status in the Emergency Department.

OBJECTIVES: To evaluate the proportion of children presenting to the emergency department (ED) with altered mental status who demonstrate nonconvulsive seizures on reduced-lead electroencephalography (EEG), and to further investigate the characteristics, treatment, and outcomes in these patients compared with patients without nonconvulsive seizures. STUDY DESIGN: In this retrospective cohort study, we reviewed the database and medical records of pediatric patients (aged <18 years) in a single ED between May 1, 2016, and April 30, 2018. We first determined the proportion of nonconvulsive seizures among patients with altered mental status (Glasgow Coma Scale <15). We then compared the clinical presentation, demographic data, clinical diagnosis, EEG results, treatment, and outcomes of patients with altered mental status with nonconvulsive seizures and those without nonconvulsive seizures. RESULTS: In total, 16.9% of the patients with altered mental status (41 of 242; 95% CI, 12.2%-21.6%) evaluated by EEG had detectable nonconvulsive seizure, equivalent to 4.4% (41 of 932) of all patients with altered mental status presenting at our hospital. More than 80% of patients monitored for nonconvulsive seizures had a previous history of seizures, often febrile. Patients with nonconvulsive seizures were older (median, 68.5 vs 36.1 months) and had a higher Pediatric Cerebral Performance Category score at presentation (median, 2.0 vs 1.0). In addition, the proportion of patients admitted to the intensive care unit was significantly higher in the patients with nonconvulsive seizures (30.3% vs 15.0%). However, total duration of hospitalization, neurologic sequelae, and 30-day mortality rate did not differ between the 2 groups. CONCLUSIONS: A relatively high percentage of pediatric patients with altered mental status in the ED experience nonconvulsive seizures. The use of reduced-lead EEG monitoring in the ED might facilitate the recognition and treatment of nonconvulsive seizures, especially among patients with a history of seizures.

Effects of charge balance and hydrophobicity of the surface of cytochrome c on the distribution behaviour in an ionic liquid/buffer biphasic system.

Factors contributing to the different distribution behaviour of cytochrome c were investigated in a biphasic tetrabutylphosphonium 2,4,6-trimethylbenzenesulfonate and potassium phosphate buffer system, which shows a lower critical solution temperature. To change charge balance and hydrophobicity of cytochrome c, surface modification with a few modifier molecules was applied. Surface charge and hydrophobicity affected the distribution behavior of chemically modified cytochrome c in the tetrabutylphosphonium 2,4,6-trimethylbenzenesulfonate and potassium phosphate buffer biphasic system. The distribution ratio into tetrabutylphosphonium 2,4,6-trimethylbenzenesulfonate decreased with decreasing isoelectric point of cytochrome c. Furthermore, cytochrome c possessing a low isoelectric point showed different distribution ratio depending on surface hydrophobicity. Taken together, these findings indicate that isoelectric point and surface hydrophobicity of cytochrome c are important factors controlling the distribution behavior in temperature sensitive biphasic systems.

Diurnal occurrence of complex febrile seizure and their severity in pediatric patients needing hospitalization.

Several studies describing the diurnal occurrence of febrile seizures have reported greater seizure frequency early or late in the evening relative to midnight or early morning. However, no articles have reported on the diurnal occurrence of complex febrile seizure. Moreover, no studies have addressed the relationship between seizure severity and diurnal occurrence. We retrospectively evaluated complex febrile seizures in 462 children needing hospitalization, and investigated the relationship between severity and diurnal occurrence according to four categorized time periods (morning, afternoon, evening, and night). Our study showed that complex febrile seizures occurred most often in the evening, peaking around 18:00 (18:00-18:59), and least often at night (02:00-02:59). In addition, the frequency with which patients developed status epilepticus or needed anticonvulsant treatments was also lower during the night. However, the seizure duration and the proportion of the patients who needed anticonvulsant treatment were the same among the four time periods. Furthermore, we compared three subclasses (repeated episodes of convulsions, focal seizures, and prolonged seizures (≧15min)), two of the complex features (focal seizures and prolonged seizures), and all complex features among the four time periods. However, they were the same among the four time periods. Taken together, our data indicate that although the severity of seizures was stable over a 24-hour period, the occurrence of seizures in our cohort of pediatric patients with complex febrile seizures requiring hospitalization was highest in the evening and lowest at night.

Quantitative assessment of kosmotropicity of hydrated ionic liquids by nuclear magnetic resonance.

Nuclear magnetic resonance studies revealed that the chemical shift of H2O in hydrated ionic liquids varied with their component ions. The variation reflected the formation of hydrogen bonding networks between ions and water molecules. The chemical shift relative to bulk water was used to quantitatively assess the kosmotropicity.

Findings of Optical Coherence Tomographic Angiography at the Choriocapillaris Level in Central Serous Chorioretinopathy.

PURPOSE: To reveal vascular signals at the choriocapillaris level in central serous chorioretinopathy (CSC) using optical coherence tomographic angiography (OCTA). PROCEDURES: We analyzed vascular signals at the choriocapillaris level in 58 CSC and 51 contralateral eyes by OCTA (RTVue XR Avanti with AngioVue; Optovue Inc., Fremont, Calif., USA). Data analysis included age, best corrected visual acuity (BCVA), disease duration and serous retinal detachment (SRD) height. RESULTS: Morphologically, abnormal signals at the choriocapillaris level were detected in all CSC eyes (100%), and then classified into three patterns. Age, BCVA, disease duration and SRD height showed no significant correlation with signal patterns. Thirty-one contralateral eyes (61%) showed abnormal signals at the choriocapillaris level on OCTA, while 20 (39%) had a normal pattern. CONCLUSIONS: OCTA revealed three types of abnormal signals not only in CSC eyes but also in fellow eyes without SRD. OCTA may provide information for elucidating the underlying pathogenesis of CSC.

Investigation of the Etiology of Central Serous Chorioretinopathy Using En-Face Optical Coherence Tomography and Indocyanine Green Angiography.

PURPOSE: To identify locations of hypofluorescent lesions on late-phase indocyanine green angiography (ICGA) in patients with central serous chorioretinopathy (CSC) using en-face optical coherence tomography (OCT). PROCEDURES: We retrospectively studied 25 consecutive untreated CSC patients, using swept-source OCT and ICGA. En-face swept-source OCT images were automatically segmented and flattened with Bruch's membrane (BrM). We compared the sizes of hyperreflective areas in the 25 CSC and 25 contralateral eyes on en-face images and hypofluorescent areas on ICGA after 30 min. RESULTS: All 25 CSC eyes and 13 contralateral eyes showed abnormal hypofluorescent areas on late-phase ICGA and hyperreflective areas on en-face OCT from BrM to the choriocapillaris, and these findings correlated with the abnormal areas (r = 0.9988; p < 0.001). CONCLUSIONS: In CSC patients, we detected abnormal hypofluorescence on ICGA in the late phase, which corresponded to abnormal hyperreflective areas from BrM to the choriocapillaris level in en-face images.

Characteristics of Hyperautofluorescent Choroidal Vessels within the Macular Atrophic Area Using Spectral-Domain Optical Coherence Tomography.

PURPOSE: The aim of this study was to clarify the characteristic findings in patients with geographic atrophy with or without hyperautofluorescent choroidal vessels within macular atrophic areas on short-wavelength fundus autofluorescence imaging. PROCEDURES: Sixty-seven eyes of 43 consecutive patients with macular atrophic areas were divided into groups with (group 1) and without (group 2) hyperautofluorescent choroidal vessels on fundus autofluorescence imaging and then retrospectively studied using spectral-domain optical coherence tomography. RESULTS: In group 1 (n = 21), the average subfoveal choroidal thickness was 61.5 ± 20.1 µm, and the average foveal retinal thickness was 93.0 ± 51.3 µm. On the other hand, in group 2 (n = 46), the average subfoveal choroidal thickness was 200.7 ± 83.1 µm, and the average foveal retinal thickness was 109.2 ± 58.5 µm. Although retinal thickness did not differ significantly between the two groups (p = 0.28), the difference in choroidal thickness was statistically significant (p < 0.001). CONCLUSIONS: Choroidal thinning might contribute to the hyperautofluorescence of choroidal vessels.

One-year outcomes with half-dose verteporfin photodynamic therapy for chronic central serous chorioretinopathy.

PURPOSE: To assess the 1-year outcome of half-dose verteporfin photodynamic therapy (PDT) for patients with chronic central serous chorioretinopathy (CSC). DESIGN: Retrospective, interventional case series with no controls. PARTICIPANTS: A total of 204 eyes of 204 patients with chronic CSC were studied. METHODS: Fluorescein angiography (FA) and indocyanine green angiography (ICGA) were performed before PDT. The best-corrected visual acuities (BCVAs) were measured and optical coherence tomography was performed before and 1, 3, 6, 9, and 12 months after PDT. MAIN OUTCOME MEASURES: The main outcome measures were the resolution of the serous retinal detachment (SRD), changes in BCVA, and ocular and systemic complications at 12 months. RESULTS: A total of 182 of 204 eyes (89.2%) had complete resolution of the SRD at 12 months after the PDT. Eleven eyes (5.4%) had a persistent SRD throughout the follow-up period, and 12 eyes (5.9%) had a recurrence of the SRD after an earlier resolution. One of the 12 eyes had a spontaneous resolution of the SRD 6 months after PDT. The mean±standard deviation BCVA in logarithm of the minimum angle of resolution (logMAR) units significantly improved from 0.11±0.25 before to 0.07±0.23 at 1 month, 0.02±0.23 at 3 months, 0.01±0.23 at 6 months, 0.00±0.24 at 9 months, and -0.01±0.22 at 12 months (P<0.0001). The eyes with an SRD at 12 months were more likely to have an intermediate hyperfluorescence on ICGA (chi-square test, P<0.001) and poorer BCVA before the half-dose PDT (Student t test, P=0.04) than those without SRD at 12 months. None of the patients developed any systemic complications or experienced any severe visual reduction after the half-dose PDT. However, polypoidal lesion appeared in 1 eye 8 months after the PDT. CONCLUSIONS: Half-dose PDT is an effective and safe method to treat eyes with chronic CSC with an SRD. The CSC resolved and the BCVA improved significantly after PDT. Half-dose PDT was less effective for cases without intense hyperpermeability on ICGA and those with lower BCVA before the PDT.

Improvement in vision-related function with intravitreal aflibercept: data from phase 3 studies in wet age-related macular degeneration.

PURPOSE: To evaluate the effect of intravitreal aflibercept injection on visual function in wet age-related macular degeneration (AMD). DESIGN: Prospective, multicenter, double-masked, active-controlled, parallel-group, randomized phase 3 clinical studies (VEGF Trap-Eye: Investigation of Efficacy and Safety in Wet AMD [VIEW] 1 and 2 [clinicaltrials.gov identifiers, NCT00509795 and NCT00637377, respectively]). PARTICIPANTS: Patients (n=2419) with active, treatment-naïve, exudative AMD. This analysis included patients who received intravitreal aflibercept 2.0 mg every 8 weeks (2q8; n=607) or ranibizumab 0.5 mg every 4 weeks (0.5q4; n=595). INTERVENTION: Patients were randomized 1:1:1:1 to receive intravitreal aflibercept 2q8 (after 3 initial monthly doses), intravitreal aflibercept 2q4, intravitreal aflibercept 0.5q4, or ranibizumab 0.5q4 in the study eye. Patients in the intravitreal aflibercept 2q8 group received a sham injection alternating with active treatment. MAIN OUTCOME MEASURES: The 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) was administered at baseline and at weeks 12, 24, 36, and 52. The NEI VFQ-25 subscale scores were compared between intravitreal aflibercept 2q8 and ranibizumab 0.5q4 treatment arms, the approved dosing for each agent worldwide. Change in composite NEI VFQ-25 score was evaluated based on categorical change in visual acuity (worsened, unchanged, improved). RESULTS: Baseline NEI VFQ-25 scores were similar for both treatments in both studies. Mean change from baseline to 52 weeks was similar for ranibizumab 0.5q4 and intravitreal aflibercept 2q8 across all 12 subscales, with the greatest improvements noted for mental health and general vision (9.0-11.6 points, both treatments, both studies). Improvement of 4 points or more (both treatments, both studies) also was observed for subscales near vision, distance vision, role difficulties, and dependency. Mean change from baseline to 52 weeks in NEI VFQ-25 composite score (pooled data) stratified by clinical response showed meaningful improvement only in patients who gained 5 Early Treatment Diabetic Retinopathy letters or more (7.3 and 7.8 points for intravitreal aflibercept 2q8 and ranibizumab 0.5q4, respectively). CONCLUSIONS: Visual function outcomes were similar across all NEI VFQ-25 subscales over 52 weeks for intravitreal aflibercept 2q8 and ranibizumab 0.5q4, with clinically meaningful improvement recorded in 6 of 12 subscales.

Is seven the minimum number of water molecules per ion pair for assured biological activity in ionic liquid-water mixtures?

Ionic liquids (ILs) containing small amounts of water are called hydrated ILs and they show diverse physico-chemical properties that are strongly dependent on their water content. Some properties of hydrated ILs, such as biological activity and phase transition behaviour, were found to change non-linearly, with an inflection at a water molecule to ion pair ratio of around 7:1. This critical hydration number of ILs has been discussed in this paper with respect to the state of solvated water molecules.

A simple recovery process for biodegradable plastics accumulated in cyanobacteria treated with ionic liquids.

Here, we proposed a simple recovery process for poly(3-hydroxybutyrate) (PHB) accumulated in cyanobacteria by using ionic liquids (ILs), which dissolve cyanobacteria but not PHB. First, we investigated the effects of IL polarity on hydrogen-bonding receipt ability (ß value) and hydrogen-bonding donating ability (α value) and evaluated the subsequent dissolution of cyanobacteria. We found that ILs having α values higher than approximately 0.4 and ß values of approximately 0.9 were suitable for dissolution of cyanobacteria. In particular, 1-ethyl-3-methylimidazolium methylphosphonate ([C2mim][MeO(H)PO2]) was found to dissolve cyanobacteria components, but not PHB. Thus, we verified that PHB produced in cyanobacteria could be separated and recovered by simple filtering after dissolution of cyanobacteria in [C2mim][MeO(H)PO2]. Using this technique, more than 98 % of PHB was obtained on the filter as residues separated from cyanobacteria. Furthermore, [C2mim][MeO(H)PO2] maintained the ability to dissolve cyanobacteria after a simple recycling procedure.

Non-convulsive seizures in children with infection-related altered mental status.

BACKGROUND: In the intensive care unit, the use of continuous electroencephalography (cEEG) in children with altered mental status often results in the detection of non-convulsive seizures (NCS). Children with influenza can occasionally display altered mental status, but the prevalence of NCS in children with influenza with altered mental status is yet to be determined. This study determined the prevalence of NCS in pediatric patients with altered mental status associated with influenza A(H1N1)pdm09 infection. METHODS: We retrospectively reviewed admissions to the pediatric intensive care unit between September 2009 and February 2010 and confirmed the presence of NCS on cEEG in children with influenza A(H1N1)pdm09 and with altered mental status. RESULTS: Of the 15 patients (aged 41-159 months old), NCS was identified on cEEG in five children (33%). CONCLUSIONS: Approximately one-third of the children infected with influenza A(H1N1)pdm09 with altered mental status had NCS. Further research is needed to determine if the detection and management of NCS improve outcome in these children.

Quantification of metamorphopsia in chronic central serous chorioretinopathy after half-dose verteporfin photodynamic therapy.

PURPOSE: To determine the degree of metamorphopsia before and 1 year after half-dose verteporfin photodynamic therapy in eyes with chronic central serous chorioretinopathy. METHODS: This was a retrospective, noncomparative, interventional case series. Forty-five eyes of 45 consecutive patients with chronic central serous chorioretinopathy were evaluated. The degree of metamorphopsia was measured with M-CHARTS before and at 1, 3, 6, 9, and 12 months after half-dose verteporfin photodynamic therapy. The best-corrected visual acuity was also measured. RESULTS: Forty of the 45 eyes had a complete resolution of the serous retinal detachment at 1 month, 1 eye at 3 months, and 3 eyes at 6 months. The serous retinal detachment in one eye persisted throughout the follow-up period. The mean horizontal metamorphopsia score improved significantly from 0.61 ± 0.52° at baseline to 0.49 ± 0.56° at 12 months (P = 0.04). The vertical metamorphopsia score improved significantly from 0.52 ± 0.53° at baseline to 0.33 ± 0.46° at 12 months (P = 0.005). CONCLUSION: Half-dose verteporfin photodynamic therapy for chronic central serous chorioretinopathy results in significant improvements of metamorphopsia at 1 year, especially in eyes with good best-corrected visual acuity at the baseline. Half-dose verteporfin photodynamic therapy can be a therapeutic option for patients with good visual acuity who complain of metamorphopsia.

2-(Tri-methyl-aza-nium-yl)ethyl hydrogen phosphate (phospho-choline) mono-hydrate.

In the crystal structure of the title compound, C5H14NO4P·H2O, the zwitterionic phospho-choline mol-ecules are connected by an O-H⋯O hydrogen bond between the phosphate groups, forming a zigzag chain along the b-axis direction. The chains are further connected through O-H⋯O hydrogen bonds involving water mol-ecules, forming a layer parallel to (101). Three and one C-H⋯O inter-actions are also observed in the layer and between the layers, respectively. The conformation of the N-C-C-O backbone is gauche with a torsion angle of -75.8 (2)°

Low-Frequency Spectra of Hydrated Ionic Liquids with Kosmotropic and Chaotropic Anions.

In this study, we investigated the water concentration dependence of the intermolecular vibrations of two hydrated ionic liquids (ILs), cholinium dihydrogen phosphate ([ch][dhp]) and cholinium bromide ([ch]Br), using femtosecond Raman-induced Kerr effect spectroscopy (fs-RIKES). The anions of the former and latter hydrated ILs are kosmotropic and chaotropic, respectively. We found that the spectral peak of ∼50 cm-1 shifted to the low-frequency side in hydrated [ch][dhp], indicating the weakening of its intermolecular interactions. In contrast, no change in the peak frequency of the low-frequency band at ∼50 cm-1 was observed with increasing water concentration in hydrated [ch]Br. The vibrational density of states (VDOS) spectra generated from molecular dynamics (MD) simulations were in qualitative agreement with the experimental results. Decomposition analysis of the VDOS spectra for each component revealed that the red shift of the low-frequency band in the hydrated [ch][dhp] upon water addition was essentially due to the contributions of anions and water rather than that of the cholinium cation. We also found from the low-frequency spectra of the two hydrated ILs that they differed in the concentration dependence of the 180 cm-1 band, which is assigned as a hindered translational motion of water molecules combined to form O···O stretching motions. From the relationship between the peak frequency of the low-frequency band and the bulk parameter, which is the square root of the surface tension divided by the density, we found that the peak frequency in the hydrated IL with kosmotropic [dhp]- depends on the bulk parameter, similar to the case for an aqueous solution of the typical deep eutectic solvent reline. However, the peak frequency of the hydrated IL with chaotropic Br- is constant with the bulk parameter.

Minimizing the endophthalmitis rate following intravitreal injections using 0.25% povidone-iodine irrigation and surgical mask.

BACKGROUND: To examine the efficacy of complying with an infection control manual for intravitreal injection of anti-vascular endothelial growth factor (VEGF) preparations in reducing the rate of endophthalmitis. METHODS: We retrospectively reviewed intravitreal anti-VEGF injections conducted by vitreoretinal specialists at the outpatient injection room of a single university hospital between July 2009 and July 2012. The injections were conducted following an infection control manual established by our department. Doctors and nurses wore surgical masks, and disinfected the patient's eyelid skin with 10% povidone-iodine and then the conjunctiva with 0.25% povidone-iodine. After putting a drape on the patient's face, a lid speculum was placed. The conjunctival surface was again washed with 5 ml of 0.25% povidone-iodine. After waiting at least 30 seconds, intravitreal injection was performed through povidone-iodine. Following injection, the injection site was again washed with 5 ml of 0.25% povidone-iodine. Patients were treated with topical levofloxacin 4 times a day for 3 days before and after the injection. RESULTS: A total of 15,144 injections comprising 548 injections of pegaptanib sodium, 846 injections of bevacizumab, and 13,750 injections of ranibizumab were performed. During this period, no case of suspected or proven infectious endophthalmitis occurred. The endophthalmitis rate was 0 per 15,144 injections, (95% confidence interval, 0.0-0.0%). CONCLUSION: The results suggest that endophthalmitis can be reduced to a minimum by preventing normal flora of the conjunctiva and bacteria in the oral cavity from entering the vitreous. For this purpose, an infection control manual that requires nurses and doctors to wear surgical mask and drape the patient's face, irrigate the conjunctiva with 0.25% povidone-iodine and wait at least 30 seconds before performing intravitreal injection is useful.

Therapeutic indicators of acute encephalopathy in patients with complex febrile seizures.

BACKGROUND: The aim of this study was to identify predictors of neurologic damage in children with febrile seizures or altered consciousness within 6 h of seizure onset. METHODS: The present study included 86 children (age range, 4-159 months old), who fulfilled the diagnostic criteria for complex febrile seizures on admission between October 2002 and November 2008. Using the Pediatric Cerebral Performance Category Scale (PCPC), the children were classified into two groups: poor outcome (PCPC = 2-6) and good outcome (PCPC = 1). Clinical profiles and laboratory findings were compared between the groups. RESULTS: Of the 86 children, 17 fell into the poor outcome and 69 into the good outcome group. Using univariate analysis, three early risk factors for poor outcome were identified: (i) consciousness disturbance or hemiplegia at 6 h from onset; (ii) refractory status epilepticus; and (iii) elevation of aspartate aminotransferase to >90 IU/L within 6 h of onset. Using these criteria, children in the poor outcome group were identified with a 94% sensitivity and 67% specificity rate (odds ratio, 36.6; 95% confidence interval: 4.87-1560). During the study period, the inpatients who met the criteria for acute encephalopathy also fell into the poor outcome group. CONCLUSIONS: The development of neurologic damage in children with complex febrile seizures can be predicted within 6 h of onset, using the identified risk factors. The authors propose an assumption of severe febrile seizures (SFS) in children who fulfill these risk factors. Using SFS as an inclusion criterion, an interventional study for acute encephalopathy can be designed.

Contracting cardiomyocytes in hydrophobic room-temperature ionic liquid.

Room-temperature ionic liquids (RTILs) are drawing attention as a new class of nonaqueous solvents to replace organic and aqueous solvents for chemical processes in the liquid phase at room temperature. The RTILs are notable for their characteristics of nonvolatility, extremely low vapor pressure, electric conductivity, and incombustibility. These distinguished properties of RTILs have brought attention to them in applications with biological cells and tissue in vacuum environment for scanning electron microscopy, and in microfluidic devices for micro-total analysis system (micro-TAS). Habitable RTILs could increase capability of nonaqueous micro-TAS for living cells. Some RTILs seemed to have the capability to replace water in biological applications. However, these RTILs had been applied to just supplemental additives for biocompatible test, to fixed cells as a substitute for an aqueous solution, and to simple molecules. None of RTILs in which directly soaks a living cell culture. Therefore, we demonstrated the design of RTILs for a living cell culture and a liquid electrolyte to stimulate contracting cardiomyocytes using the RTILs. We assessed the effect of RTILs on the cardiomyocytes using the beating lifetime to compare the applicability of RTILs for biological applications. Frequent spontaneous contractions of cardiomyocytes were confirmed in amino acid anion RTILs [P(8,8,8,8)][Leu] and [P(8,8,8,8)][Ala], phosphoric acid derivatives [P(8,8,8,8)][MeO(H)PO(2)], and [P(8,8,8,8)][C(7)CO(2)]. The anion type of RTILs had influence on applicable characteristics for the contracting cardiomyocyte. This result suggested the possibility for biocompatible design of hydrophobic group RTILs to achieve biological applications with living cells.