Selective therapy (cryo or scalpel) combined with multimodal therapy for treating keloids.

Background: Keloids are less responsive to any single treatment modality; hence, there is a need for combination therapy that can yield satisfactory outcomes. Objective: The present study assessed efficacy and safety of combination therapy-surgical excision or cryotherapy and intralesional corticosteroids along with 5-fluorouracil [IL (S + 5-FU)] injection, followed by silicone gel sheet (SGS) under compression therapy in the treatment of keloids. Materials and Methods: This was a retrospective, observational study comprising 21 clinically diagnosed keloid patients. All patients were treated with the stated combination therapy. Data about demographic, lesions, procedural characteristics, and treatment outcomes were reported. Results: Of 21, 11 (52.4%) patients were treated with liquid nitrogen (LN2) cryotherapy, and 10 (47.6%) patients were treated with surgical excision. Mean age was 30.8 ± 7.6 (range: 14-44) years with slight male (52.4%) predominance. A mean surface area of keloid lesion was 96.8 ± 170.5 cm3. The most frequently involved site was auricle (8 [38.1%] patients). Patients received the following types of treatments: intralesional LN2 cryotherapy (6 [28.6%]), intralesional excisional surgery (6 [28.6%]), surface LN2 cryotherapy (5 [23.8%]), and extralesional excisional surgery (4 [19.0%]). Complications of recurrence (2 [9.5%]), secondary infections (2 [9.5%]), persistent postinflammatory hypopigmentation (1 [4.8%]), and atrophic scarring with postinflammatory hyperpigmentation (1 [4.8%]) were reported. After a study period of 2.5 years, 100% cure rate was achieved. Conclusion: Combination therapy of surgical excision or cryotherapy and IL (S + 5-FU), followed by SGS under compression, was safe and effective in treating keloids.

Efficacy and Safety of Carbon Dioxide Laser Ablation Combined with Manual Dermabrasion and Intralesional 5-Fluorouracil Injection in Bowen's Disease.

Background: Bowen's disease (BD) is a precancerous in-situ squamous cell carcinoma and has a high recurrence rate with any single treatment modality, necessitating combination therapy for a successful outcome. Aim: This study aimed to the efficacy and safety of carbon dioxide (CO2) laser ablation followed by manual dermabrasion and intralesional 5-fluorouracil (IL 5-FU) injection as combination therapy for BD. Materials and Methods: This was a retrospective, observational study comprising 29 clinically and histopathologically diagnosed BD patients with no history of prior treatment. Demographic characteristics and clinical examination of the lesions and regional lymph nodes were retrieved. All patients were subjected to CO2 laser ablation followed by manual dermabrasion and IL 5-FU injection. Results: Mean age was 61.93 ± 9.31 years with male preponderance (62.1%). Trunk (48.3%) was the most frequently involved site. Mean tumor size was 40.8 ± 16.4 mm (range: 15-86 mm). All lesions healed with a cure rate of 96.6%. Complications seen in patients included atrophic scarring with persistent post-inflammatory hyperpigmentation in three patients (10.3%), secondary infection in two cases (6.9%), and hypertrophic scar with early keloid in one patient (3.4%). Recurrence was reported in one patient (3.4%). Limitation: The study was limited by retrospective study design, small sample size, and no comparison with standard therapy. Conclusion: Combination approach using carbon dioxide laser ablation followed by manual dermabrasion and IL 5-FU injection has been proved to be effective, efficient and safe with good functional, oncological and aesthetic outcomes in treating BD.

Nanoparticle-mediated dsRNA delivery for precision insect pest control: a comprehensive review.

Nanoparticle-based delivery systems have emerged as powerful tools in the field of pest management, offering precise and effective means of delivering double-stranded RNA (dsRNA), a potent agent for pest control through RNA interference (RNAi). This comprehensive review aims to evaluate and compare various types of nanoparticles for their suitability in dsRNA delivery for pest management applications. The review begins by examining the unique properties and advantages of different nanoparticle materials, including clay, chitosan, liposomes, carbon, gold and silica. Each material's ability to protect dsRNA from degradation and its potential for targeted delivery to pests are assessed. Furthermore, this review delves into the surface modification strategies employed to enhance dsRNA delivery efficiency. Functionalization with oligonucleotides, lipids, polymers, proteins and peptides is discussed in detail, highlighting their role in improving stability, cellular uptake, and specificity of dsRNA delivery.This review also provides valuable guidance on choosing the most suitable nanoparticle-based system for delivering dsRNA effectively and sustainably in pest management. Moreover, it identifies existing knowledge gaps and proposes potential research directions aimed at enhancing pest control strategies through the utilization of nanoparticles and dsRNA.

Review of the subtribe Spinariina van Achterberg (Hymenoptera: Braconidae: Rogadinae) from India with description of one new species.

The Indian members of the subtribe Spinariina van Achterberg, 1988 are reviewed and a key to Indian species is provided. Spinaria westwoodi Cameron, 1906 is reported from Great Nicobar island and a new species, Spinaria indica Gupta & van Achterberg, sp. nov. from Nagaland, is described and illustrated. In addition, Batotheca nigriceps (Cameron, 1897) is reported from caterpillars feeding on Psidium guajava L. and S. spinator (Gurin-Mneville, 1830) from slug caterpillar (Limacodidae) on Elaeodendron glaucum (Rottb.) Pers. in southern India.

A new species of the genus Scirtothrips (Thysanoptera, Thripidae) from India.

A new species of Scirtothrips is described from India, S. donumdei, collected on leaves of Senegalia pennata (Fabaceae). Partial mitochondrial cytochrome c oxidase subunit 1 (mtCOI) gene sequence of the species was sequenced and the annotated sequence was submitted to NCBI GenBank.

Expression pattern of candidate genes and their correlation with various metabolites of abscisic acid biosynthetic pathway under drought stress in rice.

Drought hampers global rice production. Abscisic acid (ABA) plays versatile roles under different environmental stresses. While the link between drought and ABA is known, its effect on ABA biosynthesis genes and metabolites is unclear. This study explored the impact of drought on various metabolites, namely beta-carotene, zeaxanthin, antheraxanthin, violaxanthin, neoxanthin, and candidate genes viz. zeaxanthin epoxidase (ZEP) and 9-cis epoxycarotenoid dioxygenase (NCED) of ABA biosynthesis pathway in rice cultivars (N22 and IR64) at anthesis {65 DAT (Days after transplanting)} with different stress levels. In stressed plants, zeaxanthin significantly increased (92%), while the concentration of beta-carotene, antheraxanthin, violaxanthin and neoxanthin decreased as drought stress progressed. The concentration of metabolites in roots was notably lower than in leaves in both genotypes. The ZEP expression was upregulated in roots (8.24-fold) under drought stress. Among five NCED isoforms, NCED3 showed significant upregulation (7.29-fold) in leaf and root tissue. NCED1 was significantly downregulated as stress progressed and was negatively correlated with ABA accumulation. NCED2, NCED4 and NCED5 showed no significant change in their expression. Drying and rolling of rice leaves was observed after imparting drought stress. The findings revealed that drought stress significantly influenced the expression of candidate genes and the concentration of metabolites of the ABA biosynthesis pathway. There was a significantly higher accumulation of ABA in N22 leaves (47%) and roots (30%) compared to IR64. The N22, a drought-tolerant genotype, exhibited significantly higher concentrations of intermediates and demonstrated increased expression of ZEP and NCED3, potentially contributing to its resilience against drought.

Nature to Nurture: Chitosan nanopowder a natural carbohydrate polymer choice of egg parasitoid, Trichogramma Japonicum Ashmead.

Chitosan is a naturally occurring linear biopolymer made of partially deacetylated acetyl and N-acetyl glucosamine. Its biocompatible physiochemical and biochemical properties are unmatched. Chitosan is transformed to nanopowder for use in agriculture and associated industries as nanocarriers for existing agrochemicals, ensuring the delayed release of chemicals with better solubility. Chitosan nanopowder applied to leaves or soil can activate a plant's natural defences against insects and pathogens. These studies were carried out because there is a potential for toxicological risk linked with products created utilizing nanotechnology, such as chitosan nanopowder, and therefore researchers felt the need to investigate this. The egg parasitoides Trichogramma Japonicum Ashmead was used as a low-cost biomarker to determine the potential toxicity of chitosan nanopowder. This study looked into the possibility that the adult stage of the egg parasitoids, Trichogramma Japonicum Ashmead might be negatively impacted by chitosan nanopowder (80-100 nm). Unpaired t-test statistical analysis has been carried out. According to the statistical analysis, host eggs exposed to chitosan nanopowder showed noticeably greater parasitization than the control group. As a natural supply of carbohydrate polymers chitosan nanopowder promotes the parasitization of T. Japonicum. The findings showed that T. Japonicum favoured chitosan nanopowder. Through Y dual choice, eight-arm multiple choice, and no-choice olfactometer experiments, as well as images from a stereozoom microscope and a scanning electron microscope (SEM), the data was thoroughly supported. Future agricultural applications of chitosan nanopowder will benefit from a deeper understanding of our findings.

Elevated translationally controlled tumour protein promotes oral cancer progression and poor outcome.

BACKGROUND: Translationally controlled tumour protein (TCTP) is a multifunctional protein elevated in multiple cancers. However, studies on its role in oral carcinogenesis and prognosis are rare. We recently reported the role of its interacting partner, MCL1, in oral cancer progression and outcome. Hence, the present study aimed to assess TCTP expression in oral tumorigenesis and its association with patient outcomes alone and in combination with MCL1. METHODS: TCTP expression was assessed by immunohistochemistry and immunoblotting in oral tissues and cells, respectively. Cell viability post siRNA/dihydroartemisinin treatment was analysed by tetrazolium salt assay. Cell survival, invasion and tumorigenic potential post TCTP knockdown were assessed by clonogenic, Matrigel and soft-agar assays, respectively. The association of TCTP with patient outcome was analysed by Kaplan-Meier and Cox regression. RESULTS: TCTP was significantly overexpressed in oral premalignant lesions (p < 0.0001), oral tumours (p < 0.0001) and oral dysplastic and cancer cells versus normal oral mucosa and also in recurrent (p < 0.05) versus non-recurrent oral tumours. Further, elevated TCTP was significantly (p < 0.05) associated with poor recurrence free survival (RFS) and poor overall survival (OS; hazard ratio = 2.29; p < 0.05). Intriguingly, the high co-expression of TCTP and MCL1 further reduced the RFS (p < 0.05) and OS (p < 0.05; hazard-ratio = 3.49; p < 0.05). Additionally, TCTP knockdown decreased survival (p < 0.05), invasion (p < 0.01) and in vitro tumorigenic potential (p < 0.0001). Dihydroartemisinin treatment reduced TCTP levels and viability of oral cancer cells. CONCLUSION: Our studies demonstrate an oncogenic role of TCTP in oral cancer progression and poor outcome. Thus, TCTP may be a potential prognostic marker and therapeutic target in oral cancers.

Chemical Bridge-Mediated Heterojunction Electron Transport Layers Enable Efficient and Stable Perovskite Solar Cells.

Perovskite solar cells (PSCs) emerged as potential photovoltaic energy-generating devices developing in recent years because of their excellent photovoltaic properties and ease of processing. However, PSCs are still reporting efficiencies much lower than their theoretical limits owing to various losses caused by the charge transport layer and the perovskite. In this regard, herein, an interface engineering strategy using functional molecules and chemical bridges was applied to reduce the loss of the heterojunction electron transport layer. As a functional interface layer, ethylenediaminetetraacetic acid (EDTA) was introduced between PCBM and the ZnO layer, and as a result, EDTA simultaneously formed chemical bonds with PCBM and ZnO to serve as a chemical bridge connecting the two. DFT and chemical analyses revealed that EDTA can act as a chemical bridge between PCBM and ZnO, passivate defect sites, and improve charge transfer. Optoelectrical analysis proved that EDTA chemical bridge-mediated charge transfer (CBM-CT) provides more efficient interfacial charge transport by reducing trap-assisted recombination losses at ETL interfaces, thereby improving device performance. The PSC with EDTA chemical bridge-mediated heterojunction ETL exhibited a high PCE of 21.21%, almost no hysteresis, and excellent stability to both air and light.

Retrospective analysis of ultrathin skin grafting over carbon dioxide ablated lesions supplemented with excimer lamp (308 nm) therapy in stable vitiligo.

Background Of all the tissue or cellular grafting techniques used in the treatment of vitiligo, melanocyte transplant/transfer through ultrathin skin grafting (UTSG) provides rapid onset of regimentation. The regimentation process is further accelerated with a combination of psoralen and ultraviolet A radiation, or psoralen and ultraviolet A obtained by sunlight or narrowband ultraviolet light B, or excimer laser/lamp (308 nm). Aims We assessed the efficacy of carbon dioxide laser ablation followed by melanocyte transplant/transfer through ultrathin skin graft sheet/sheets and further treated by excimer lamp therapy in patients with stable vitiligo. Methods One hundred ninety-two patients with stable vitiligo were treated with UTSG following carbon dioxide laser ablation and patients were then put on excimer lamp therapy. Primary efficacy was determined in terms of grades of regimentation and colour match at the end of 1-year. Results A total of 192 stable vitiligo patients with a mean age of 32.71 ± 8.55 years were recruited. Of the total 410 lesions, 394 showed excellent regimentation indicating a success rate of 96.1% at 1-year follow-up, whereas 16 (3.9%) lesions present on fingertips and toe tips showed poor or no regimentation at 3-month and 1-year follow-up. With regards to colour match, 394 (96.1%) lesions had achieved excellent colour match, and 16 lesions (3.9%) had poor or no colour match at 1-year follow-up. Limitations This was a single-center study with a small sample size. Conclusion The effectiveness of carbon dioxide laser ablation followed by melanocyte transfer/transplant through ultra-thin skin graft sheet/sheets when combined with excimer lamp therapy provides favourable cosmetic outcomes with rapid onset of regimentation in stable vitiligo.

Use of preoperative and perioperative ex vivo dermoscopy for precise mapping of margins for standard surgical excision of primary basal cell carcinoma.

Background The utility of preoperative and perioperative dermoscopy in standard surgical excision for radical excision of primary basal cell carcinoma remain unexplored. Aims To evaluate the use of preoperative and perioperative dermoscopy for precise mapping of margins during standard surgical excision of primary basal cell carcinoma. Methods In this retrospective, observational study, 17 patients clinically diagnosed with various morphological subtypes of basal cell carcinoma were included. Data about previous history, clinical examination of lesions and regional lymph nodes and preoperative dermoscopy were retrieved. After standard surgical excision had been carried out as per mapping of lateral margins, all the excised surgical specimens were subjected to perioperative dermoscopy and later reconfirmed with histopathology. Results Seventeen patients with mean age of 60.82 ± 9.99 years and median disease duration of 14 months were analysed. Clinically, basal cell carcinomas were of pigmented superficial subtype [6 (35.3%)], followed by pigmented nodular [5 (29.4%)], nodulo-ulcerative [4 (23.5%)] and micro nodular [2 (11.8%)]. Mean extension of clinical margin after dermoscopy was 0.59 ± 0.52 mm. Mean pre-assessed depth of tumour and mean depth of tumour were 3.46 ± 0.89 mm and 3.49 ± 0.92 mm, respectively. No recurrence was reported. Frequently found pre-operative dermoscopic features were maple leaf like structures [6 (35%)], blue grey dots and globules [6 (35%)] and short fine telangiectasias [6 (35%)]. Commonly observed perioperative dermoscopic features were: (1) irregular band with brown-grey pigmentation of dots, globules, streaks and pseudopodia like extensions [3 (50%)]; (2) irregular band of pseudo granulomatous structureless vascular areas in psoriasiform pattern with diffuse white streaks in pseudopodia like manner [1 (50%)]; (3) irregular band of pseudo granulomatous structureless vascular areas in psoriasiform pattern with streaks of white pseudopodia like structureless areas [1 (50%)]. Limitation This was a single-centre study with a small sample size. Conclusion This study highlights significance of preoperative and perioperative dermoscopy for precise planning and radical excision of primary basal cell carcinoma by standard surgical excision.

Health-Promoting compounds in Potatoes: Tuber exhibiting great potential for human health.

Potatoes are consumed worldwide because of their high accessibility, low cost, taste, and diversity of cooking methods. The high carbohydrate content of potatoes masks the presence of -vitamins, polyphenols, minerals, amino acids, lectins and protein inhibitors in the minds of consumers. The consumption of potatoes faces challenges among health-conscious people. This review paper attempted to provide up-to-date information on new metabolites reported in potatoes that play role in disease prevention and overall human well-being. We tried to compile information on antidiabetic, antihypertensive, anticancer, antiobesity, antihyperlipidemic, and anti-inflammatory potential of potato along with role in improving gut health and satiety. In-vitro studies, human cell culture, and experimental animal and human clinical studies showed potatoes to exhibit a variety of health-enhancing properties. This article will not only popularize potato as a healthy food, but will also improve its use as a staple for the foreseeable future.

Innovative Approaches to Semi-Transparent Perovskite Solar Cells.

Perovskite solar cells (PSCs) are advancing rapidly and have reached a performance comparable to that of silicon solar cells. Recently, they have been expanding into a variety of applications based on the excellent photoelectric properties of perovskite. Semi-transparent PSCs (ST-PSCs) are one promising application that utilizes the tunable transmittance of perovskite photoactive layers, which can be used in tandem solar cells (TSC) and building-integrated photovoltaics (BIPV). However, the inverse relationship between light transmittance and efficiency is a challenge in the development of ST-PSCs. To overcome these challenges, numerous studies are underway, including those on band-gap tuning, high-performance charge transport layers and electrodes, and creating island-shaped microstructures. This review provides a general and concise summary of the innovative approaches in ST-PSCs, including advances in the perovskite photoactive layer, transparent electrodes, device structures and their applications in TSC and BIPV. Furthermore, the essential requirements and challenges to be addressed to realize ST-PSCs are discussed, and the prospects of ST-PSCs are presented.

Elucidation of pH-Induced Protein Structural Changes: A Combined 2D IR and Computational Approach.

The acid-base behavior of amino acids plays critical roles in several biochemical processes. Depending on the interactions with the protein environment, the pKa values of these amino acids shift from their respective solution values. As the side chains interact with the polypeptide backbone, a pH-induced change in the protonation state of aspartic and glutamic acids might significantly influence the structure and stability of a protein. In this work, we have combined two-dimensional infrared spectroscopy and molecular dynamics simulations to elucidate the pH-induced structural changes in an antimicrobial enzyme, lysozyme, over a wide range of pH. Simultaneous measurements of the carbonyl signals arising from the backbone and the acidic side chains provide detailed information about the pH dependence of the local and global structural features. An excellent agreement between the experimental and the computational results allowed us to obtain a residue-specific molecular understanding. Although lysozyme retains the helical structure for the entire pH range, one distinct loop region (residues 65-75) undergoes local structural deformation at low pH. Interestingly, combining our experiments and simulations, we have identified the aspartic acid residues in lysozyme, which are influenced the most/least by pH modulation.

Isolation and characterization of drought and ABA responsive promoter of a transcription factor encoding gene from rice.

Water deficit is a significant impediment to enhancing rice yield. Genetic engineering tools have enabled agriculture researchers to develop drought-tolerant cultivars of rice. A common strategy to achieve this involves expressing drought-tolerant genes driven by constitutive promoters such as CaMV35S. However, the use of constitutive promoters is often limited by the adverse effects it has on the growth and development of the plant. Additionally, it has been observed that monocot-derived promoters are more successful in driving gene expression in monocots than in dicots. Substitution of constitutive promoters with stress-inducible promoters is the currently used strategy to overcome this limitation. In the present study, a 1514 bp AP2/ERF promoter that drives the expression of a transcription factor was cloned and characterized from drought-tolerant Indian rice genotype N22. The AP2/ERF promoter was fused to the GUS gene (uidA) and transformed in Arabidopsis and rice plants. Histochemical GUS staining of transgenic Arabidopsis plants showed AP2/ERF promoter activity in roots, stems, and leaves. Water deficit stress and ABA upregulate promoter activity in transformed Arabidopsis and rice. Quantitative PCR for uidA expression confirmed induced GUS activity in Arabidopsis and rice. This study showed that water deficit inducible Os-AP2/ERF-N22 promoter can be used to overcome the limitations of constitutive promoters. Transformants overexpressing Os-AP2/ERF-N22 showed higher relative water content, membrane stability index, total chlorophyll content, chlorophyll stability index, wax content, osmotic potential, stomatal conductance, transpiration rate, photosynthetic rate and radical scavenging activity. Drought tolerant (N22) showed higher expression of Os-AP2/ERF-N22 than the susceptible (MTU1010) cultivar. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01246-9.

Integrated analysis of DNA methylation, transcriptome, and global metabolites in interspecific heterotic Capsicum F1 hybrid.

Hybrid breeding is one of the efficacious methods of crop improvement. Here, we report our work towards understanding the molecular basis of F1 hybrid heterosis from Capsicum chinense and C. frutescens cross. Bisulfite sequencing identified a total of 70597 CG, 108797 CHG, and 38418 CHH differentially methylated regions (DMRs) across F1 hybrid and parents, and of these, 4891 DMRs showed higher methylation in F1 compared to the mid-parental methylation values (MPMV). Transcriptome analysis showed higher expression of 46-55% differentially expressed genes (DE-Gs) in the F1 hybrid. The qRT-PCR analysis of 24 DE-Gs with negative promoter methylation revealed 91.66% expression similarity with the transcriptome data. A few metabolites and 65-72% enriched genes in metabolite biosynthetic pathways showed overall increased expression in the F1 hybrid compared to parents. These findings, taken together, provided insights into the integrated role of DNA methylation, and genes and metabolites expression in the manifestation of heterosis in Capsicum.

An Overview of Diabetic Foot Ulcers and Associated Problems with Special Emphasis on Treatments with Antimicrobials.

One of the most significant challenges of diabetes health care is diabetic foot ulcers (DFU). DFUs are more challenging to cure, and this is particularly true for people who already have a compromised immune system. Pathogenic bacteria and fungi are becoming more resistant to antibiotics, so they may be unable to fight microbial infections at the wound site with the antibiotics we have now. This article discusses the dressings, topical antibacterial treatment, medications and debridement techniques used for DFU and provides a deep discussion of DFU and its associated problems. English-language publications on DFU were gathered from many different databases, such as Scopus, Web of Science, Science Direct, Springer Nature, and Google Scholar. For the treatment of DFU, a multidisciplinary approach involving the use of diagnostic equipment, skills, and experience is required. Preventing amputations starts with patient education and the implementation of new categorization systems. The microbiota involved in DFU can be better understood using novel diagnostic techniques, such as the 16S-ribosomal DNA sequence in bacteria. This could be achieved by using new biological and molecular treatments that have been shown to help prevent infections, to control local inflammation, and to improve the healing process.

Anti-barnacle biofouling coatings for the protection of marine vessels: synthesis and progress.

Marine biofouling has gnawed both mobile and non-mobile marine structures since time immemorial, leading to the deterioration of designed operational capabilities as well as a loss of valuable economic revenues. Mitigation of biofouling has been the primary focus of researchers and scientists from across the globe to save billions of dollars wasted due to the biological fouling of marine structures. The availability of an appropriate environment along with favorable substrata initiates biofilm formation within a few minutes. The crucial element in establishing a gelatinous biofilm is the excreted metabolites of destructive nature and exopolymeric substances (EPSs). These help in securing as well as signaling numerous foulants to establish themselves on this substrate. The larvae of various benthic invertebrates adhere to these suitable surfaces and transform from juveniles to adult barnacles depending upon the environment. Despite biofouling being characteristically witnessed for a month or lengthier timeframe, the preliminary phases of the fouling process typically transpire on a much lesser timescale. A few natural and synthetic additives had demonstrated excellent non-toxic anti barnacle establishment capability; however, further development into commercial products is still far-fetched. This review collates the specific anti-barnacle coatings, emphasizing natural additives, their sources of extraction, general life cycle analysis, and concluding future perspectives of this niche product.

Association-Dissociation Dynamics of Ionic Electrolytes in Low Dielectric Medium.

Ionic electrolytes are known to form various complexes which exist in dynamic equilibrium in a low dielectric medium. However, structural characterization of these complexes has always posed a great challenge to the scientific community. An additional challenge is the estimation of the dynamic association-dissociation time scales (lifetime of the complexes), which are key to the fundamental understanding of ion transport. In this work, we have used a combination of infrared absorption spectroscopy, two-dimensional infrared spectroscopy, molecular dynamics simulations, and density functional theory calculations to characterize the various ion complexes formed by the thiocyanate-based ionic electrolytes as a function of different cations in a low dielectric medium. Our results demonstrate that thiocyanate is an excellent vibrational reporter of the heterogeneous ion complexes undergoing association-dissociation dynamics. We find that the ionic electrolytes exist as contact ion pairs, dimers, and clusters in a low dielectric medium. The relative ratios of the various ion complexes are sensitive to the cations. In addition to the interactions between the thiocyanate anion and the countercation, the solute-solvent interactions drive the dynamic equilibrium. We have estimated the association-dissociation dynamics time scales from two-dimensional infrared spectroscopy. The exchange time scale involving the cluster is faster than that between a dimer and an ion pair. Moreover, we find that the dynamic equilibrium between the cluster and another ion complex is correlated to the solvent fluctuations.

Transition of a Deep Eutectic Solution to Aqueous Solution: A Dynamical Perspective of the Dissolved Solute.

Disruption of the deep eutectic solvent (DES) nanostructure around the dissolved solute upon addition of water is investigated by polarization-selective two-dimensional infrared spectroscopy and molecular dynamics simulations. The heterogeneous DES nanostructure around the solute is partially retained up to 41 wt % of added water, although water molecules are gradually incorporated in the solute's solvation shell even at lower hydration levels. Beyond 41 wt %, the solute is observed to be preferentially solvated by water. This composition denotes the upper hydration limit of the deep eutectic solvent above which the solute senses an aqueous solvation environment. Interestingly, our results indicate that the transition from a deep eutectic solvation environment to an aqueous one around the dissolved solute can happen at a hydration level lower than that reported for the "water in DES" to "DES in water" transition.