Color Alteration Research Articles

Influence of myoinositol on post-ripening and softening of Prunus salicina ‘Wushan plum’

To investigate the impact of myoinositol (MI) immersion treatment on the storage characteristics of Prunus salicina ‘Wushan Plum’, we assessed myoinositol content, ascorbic acid content, weight loss, decay rate, alteration in color, titratable acidity (TA), soluble solids (TSS), firmness, cell wall metabolism-related compounds, enzyme activities, and levels of gene expression throughout a 15-day storage period at 25 °C. The results revealed that MI treatment could increase myoinositol and ascorbic acid contents of fruit during the pre-storage period, effectively delay the color transformation and decay progression of P. salicina ‘Wushan Plum’ while maintaining elevated levels of TA and TSS. Furthermore, it suppressed the increase in weight loss and the decline in firmness. Notably, the delay in softening was more pronounced in the group treated with 100 mg L−1 MI compared to other groups. MI treatment regulated the expression levels of various genes associated with cell wall metabolism, which resulted in reduced activities of polygalacturonase (PG), pectate lyase (PL), pectin methylesterase (PME), cellulase (Cx), and β-glucosidase (β-Glu), and increased activities of phenylalanine ammonia-lyase (PAL) and cinnamyl alcohol dehydrogenase (CAD). Furthermore, MI treatment maintained higher levels of covalently bound pectin (CSP), cellulose, and lignin, while decreasing the levels of water-soluble pectin (WSP) in the fruit. As a result, MI treatment could delay the depolymerization of cell wall polysaccharides and further delay the quality deterioration of P. salicina ‘Wushan Plum’ fruits under ambient storage environment and prolong the storage period.

Osteogenesis imperfecta: a cross-sectional study of skeletal and extraskeletal features in a large cohort of Italian patients.

The present study aims to describe a large cohort of Italian patients affected by osteogenesis imperfecta, providing a picture of the clinical bony and non-bony features and the molecular background to improve knowledge of the disease to inform appropriate management in clinical practice. A total of 568 subjects (from 446 unrelated Italian families) affected by osteogenesis imperfecta who received outpatient care at Istituto Ortopedico Rizzoli from 2006 to 2021 were considered in the present study. Skeletal and extraskeletal features were analyzed showing a lower height (mean z-scores equal to -1.54 for male patients and -1.47 for female patients) compared with the general Italian population. Half of the patient population showed one or more deformities, and most of the patients had suffered a relatively low number of fractures (<10). An alteration in the sclera color was identified in 447 patients. Similarly, several extraskeletal features, like deafness, dental abnormalities, and cardiac problems, were investigated. Additionally, inheritance and genetic background were evaluated, showing that most of the patients have a positive family history and the majority of pathogenic variants detected were on collagen genes, as per literature. This study supports the definition of a clear picture of the heterogeneous clinical manifestations leading to variable severity in terms of skeletal and extra-skeletal traits and of the genetic background of an Italian population of osteogenesis imperfecta patients. In this perspective, this clearly highlights the crucial role of standardized and structured collection of high-quality data in disease registries particularly in rare disease scenarios, helping clinicians in disease monitoring and follow-up to improve clinical practice.

Smart Nanofibrous Hydrogel Wound Dressings for Dynamic Infection Diagnosis and Control: Soft but Functionally Rigid.

Chronic wounds, such as burns and diabetic foot ulcers, pose significant challenges to global healthcare systems due to prolonged hospitalization and increased costs attributed to susceptibility to bacterial infections. The conventional use of antibiotic-loaded and metal-impregnated dressings exacerbates concerns related to multidrug resistance and skin argyrosis. In response to these challenges, our research introduces a unique approach utilizing antibiotic-free smart hydrogel wound dressings with integrated infection eradication and diagnostic capabilities. Electrospinning stands out as a method capable of producing hydrogel nanofibrous materials possessing favorable characteristics for treating wounds and detecting infections under conditions utilizing sustainable materials. In this study, innovative dressings are fabricated through electrospinning polycaprolactone (PCL)/gelatin (GEL) hybrid hydrogel nanofibers, incorporating pDA as a cross-linker, εPL as a broad-spectrum antimicrobial agent, and anthocyanin as a pH-responsive probe. The developed dressings demonstrate exceptional antioxidant (>90% radical scavenging) and antimicrobial properties (95-100% killing). The inclusion of polyphenols/flavonoids and εPL leads to absolute bacterial eradication, and in vitro assessments using HaCaT cells indicate increased cell proliferation, decreased reactive oxygen species (ROS) production, and enhanced cell viability (100% Cell viability). The dressings display notable alterations in color that correspond to different wound conditions. Specifically, they exhibit a red/violet hue under healthy wound conditions (pH 4-6.5) and a green/blue color under unhealthy wound conditions (pH > 6.5). These distinctive color changes provide valuable insights into the versatile applications of the dressings in the care and management of wounds. Our findings suggest that these antibiotic-free smart hydrogel wound dressings hold promise as an effective and sustainable solution for chronic wounds, providing simultaneous infection control and diagnostic monitoring. This research contributes to advancing the field of wound care, offering a potential paradigm shift in the development of next-generation wound dressings.

Utilizing symmetrical tetramethyl cucurbit[6]uril-based supramolecular fluorescence probe for detection of paraquat in water

A supramolecular fluorescence probe has been developed using a symmetrical tetramethyl cucurbit[6]uril (TMeQ[6]) and a styryl derivative (SPy) with a host–guest ratio of 2:1. The introduction of paraquat (PQ) competes with SPy for the TMeQ[6] cavity, resulting in fluorescent quenching. The addition of 17 common herbicides and ions had negligible effects on the fluorescence quenching, indicating that the 2TMeQ[6]/SPy complex exhibits excellent selectivity in detecting PQ. The detection limit was found to be 4.62 × 10-7 M. More importantly, the probe was engineered to detect paraquat in river water by examining post-treatment samples and noting alterations in fluorescence color. The red to blue (R/B) intensity ratio is subsequently calculated to ascertain the PQ concentration. Experimental trials conducted on river water samples yielded recovery rates between 98.21 % and 108 %, with a relative standard deviation of less than 5 %. By pairing this with a smartphone-based colorimetric analysis application, we can facilitate portable PQ detection, enabling efficient and convenient monitoring across various locations.

Dietary supplementation with natural antioxidants: assessment of growth performance and meat quality in broiler chickens

Exposure to air and light lowers the meat quality of chickens, which is mainly determined by the color alteration and accumulation of detrimental products from lipid oxidation. This study tests the effects of two supplements rich in polyphenols, Oxilem (OX) and OxiGem (OG), on broiler Ross 308 performance and meat quality in comparison to a control group (C). A total of 105 one-day-old Ross 308 male chicks were allocated to 21 pens and randomly assigned to one of the three treatments. The trial lasted 42 days. Individual live weight and feed intake per pen were recorded. Proximate analysis, color, cholesterol content and cholesterol oxidation products (COPs), fatty acids (FAs), volatile aldehydes profile, and secondary oxidation products of meat FAs were determined, with analyses for detecting oxidative alterations conducted on breast burgers preserved for seven days at 4°C. Birds fed OG grew 7 g/day more than those receiving OX, reaching a higher final weight. After slaughtering, meat from the OX group had a higher yellow index compared to C. After seven days of air and light exposure, the influence on the color parameters of the OG and OX burgers was significantly less pronounced than that of C. Secondary oxidation products of the FAs of the burgers were not significantly affected by the diet regimens. In addition, OX and OG burgers exhibited lower amounts of volatile aldehydes, triol and COPs. These results confirm the effectiveness of OX and OG supplementation against lipid oxidation at the inclusion level used in this trial.

Giant Congenital Melanocytic Nevi: A Case Report in Madinah, Saudi Arabia

Giant congenital melanocytic nevi (GCMN) is an uncommon disorder that impacts newborns, with a prevalence of less than 1 in 20,000 births. Even though it is uncommon, detecting the condition early is essential because of the higher chance of complications such as malignant melanoma, central nervous system involvement, and negative effects on the patient and their family's mental well-being due to its unattractive appearance. A giant congenital melanocytic nevus (GCMN) is described as a dark brown skin lesion acquired at birth that has the potential to grow to over 40 cm in size as a person reaches adulthood. The diagnosis of the GCMN is clinically confirmed, while management is mainly symptomatic. Nevertheless, treatment options could consist of surgical and non-surgical methods, psychological therapy, and/or regular clinical monitoring, taking into account alterations in color, size, texture, or the area of the lesion. We describe here a case of GCMN in a male neonate observed in our practice. The patient presented with a huge, pigmented patch over the body since birth, encompassing the entire abdomen, extending to the chest, thighs, and genitalia with multiple satellite, a few lesions on the face, and laterally towards the posterior aspect of the trunk, involving the entire back and buttocks. Radiological investigations were performed and were reported as normal with no significant findings. Additionally, the MRI also did not indicate any involvement of the central nervous system; hence, multidisciplinary comprehensive care was followed for this neonate with monthly regular follow-ups at dermatology and pediatric clinics. Our case significantly highlights the observatory interdisciplinary management of this condition; however, if needed in the future, surgical intervention maybe considered to decrease the risk of malignancy.

Mechanism underlying ultraviolet-irradiation-induced discoloration of dental zirconia ceramics stabilized with 3 and 5 mol% yttria

The present study aimed to analyze the mechanism underlying the color alteration of dental zirconia ceramics stabilized with 3 and 5 mol% yttria (3YZ and 5YZ, respectively) caused by 254-nm ultraviolet (UV) irradiation. Fully sintered specimens of 3YZ (Zpex, Tosoh) and 5YZ (Zpex Smile, Tosoh) were irradiated with 254-nm UV at 4 mW/cm2 (up to 60 min). Color alteration (ΔE) was analyzed using the CIE L*a*b* colorimetric system. The UV-induced excitation of oxygen vacancies, which capture two electrons in zirconia (i.e., F center) was analyzed using photoluminescence (PL) and electron spin resonance (ESR) spectroscopy. Furthermore, the spontaneous change in ΔE after cessation of UV irradiation was evaluated. UV irradiation increased ΔE to 13.4 in 3YZ and 10.3 in 5YZ within the initial 10 min of irradiation, and then, ΔE reached a plateau. A PL peak was observed at 435 nm, which decreased with UV irradiation. In addition, UV irradiation generated an ESR signal attributed to the F+ centers formed via one-electron detachment from F centers. The signal intensities of both 3YZ and 5YZ increased with irradiation time; however, the signal intensity was higher in 3YZ than that in 5YZ. After cessation of UV irradiation, ΔE gradually decreased to approximately 2, which took a few weeks. The discoloration of 3YZ and 5YZ caused by UV irradiation was due to the excitation of F centers. Although the specimens spontaneously reverted to their original color over time, clinical procedures involving UV irradiation, such as photo-functionalization, should be performed with caution to avoid damaging the esthetics of dental zirconia restorations.

Analysis of color stability and degree of conversion of different types of resin composites.

Resin composites containing surface pre-reacted glass (S-PRG) have been introduced to reduce demineralization and improve remineralization of the tooth structure. However, water diffusion within the material is necessary for its action, which can impair its overall physicomechanical properties over time, including color stability. This study aimed to evaluate the color stability and related degree of conversion (DC) of four resin composites. Discs (6 x 4 mm, n = 5/group) of microhybrid (MH), nanofilled (NF), nanohybrid (NH), and S-PRG-based nanohybrid (S-PRG-NH) composites with two opacities (A2/A2E and A2O/A2D) were prepared. Color (CIELab and CIEDE2000) was evaluated with a spectrophotometer after aging in grape juice (2 x 10 min/10mL/7days). The DC was analyzed by using Fourier transform infrared spectroscopy before and after light-curing. Data were statistically analyzed by using two-way analysis of variance and post-hoc least significant difference tests (p<0.05). In the color stability analysis, the interaction between filler type and opacity was significant (CIELab, p = 0.0015; CIEDE2000, p = 0.0026). NH presented the highest color stability, which did not differ from that of MH. The greatest color alteration was observed for S-PRG-NH. S-PRG fillers also influenced DC (p < 0.05). The nanohybrid resin composite presented favorable overall performance, which is likely related to its more stable organic content. Notwithstanding the benefits of using S-PRG-based nanohybrid resins, mostly in aesthetic procedures, professionals should consider the susceptibility of such resins to color alteration, probably due to the water-based bioactive mechanism of action.

Color alteration of CAD/CAM 3D-printed, milled resin-ceramic hybrid material compared to enamel.

To assess color and translucency change (∆E00 and ∆TP) of 3D-printed (Varseosmile crown plus, VS) and milled resin-ceramic hybrid material (Cerasmart, CS) compared to enamel (E) when immersed in distilled water (DW) and coffee (C). Sixty VS, CS, and E specimens were immersed in DW and C for 30 days. Statistics analysis using t-test and one-way ANOVA at p≤0.05. ∆E00 of VS, CS, and E significantly increased when immersed in coffee (p<0.001, p<0.001 and p=0.01, respectively). E has more ∆E00 than VS and CS (p<0.001). The translucency of VS and CS was reduced after water and coffee immersion. The translucency of E was increased after immersion in water and coffee. ∆TP of VS, CS, and E were not different between immersion in water and coffee at p=0.08, p=0.43 and p=0.72, respectively. Therefore, DW and C have distinct effects on the ∆E00 and ∆TP among VS, CS and E.

Reversible thermochromism of CsPbBr3-doped tellurite glass

Perovskite quantum dots (PQDs) have emerged as a promising research field and dynamic modulation of PQDs could induce reversible color alterations of PQD-doped glass.

Impact of effervescent denture cleaning tablets on color and surface characteristics of additively manufactured and hand-cast splint materials.

This study is to evaluate the color stability, surface roughness, and hardness of additively manufactured and hand-cast splint materials after a 6-month commercially available denture cleaning tablet immersion simulation. Disc-shaped additively manufactured and hand-cast auto polymerizing acrylic resin specimens were prepared (N = 40 each). All specimens were exposed to coffee solution totally 2days. Thereafter, all specimens were immersed into three different effervescent solutions that simulated 6months of clinical use. The total color change (ΔE*ab), surface roughness (Ra), and Vickers hardness (Vh) were measured at baseline and after immersion protocols. A two-way ANOVA and Bonferroni's post hoc test were used for color change. The dependent t-test and ANOVA were used for roughness and hardness evaluation. Additively manufactured splint materials were more affected by coffee immersion. It was observed that all denture cleaning tablets induced a noticeable alteration in color of the specimens (p < 0.05). Roughness and hardness measurement changes after solution immersions were statistically significant for both splint groups (p < 0.05). On the other hand, distilled water and denture cleaning tablets created similar roughness and hardness measurements at baseline and after immersion. After 6months use of tested cleaning tables, the color stability, surface roughness, and hardness of both groups were affected. The evaluation of the surface properties of splint materials could be recommended to the dentists in periodic controls during splint treatments. The use effervescent denture cleaning tablets altered the surface characteristics of tested splint materials over time with nonsignificant difference between each other. After 6months, awareness should be raised about surface characteristics of splint materials.

Inovasi Desain Kemasan Untuk Meningkatkan Penjualan Produk Umkm Healthy Tasty Food Surabaya

Packaging design innovation is a crucial strategy in boosting product sales. Innovation is the practical development and improvement of an initial discovery into a technique that can be used. This research aims to enhance the sales of banana chips produced by the Small and Medium Enterprises (UMKM) Healthy Tasty Food Surabaya through packaging design innovation implemented by interns from WMK.The research methods encompassed interviews, observations, brainstorming, active participation, and documentation. The results indicate that the implemented packaging design innovation successfully increased the sales of Healthy Tasty Food Surabaya's banana chips, as evidenced by a surge in orders and sales.The packaging design innovation involved alterations in shape, color, and packaging material. The new packaging was designed to be more appealing and informative, incorporating bright colors and attractive graphics. Additionally, the new packaging was equipped with comprehensive product information, including nutritional content and expiration date.The positive impact of this packaging design innovation is evident in the increased number of orders and sales for the UMKM, as well as improved customer satisfaction and product image. This research provides a significant contribution to similar UMKMs by uncovering the potential for sales enhancement through the improvement of their product packaging design quality.

A highly specific colorimetric and fluorometric sensor for ClO− and Fe3+ based on a pyrene derivative

In this study, a pyrene-based amphiphilic molecule (Pmvb) was designed and synthesized, which could self-assemble into rod-like aggregates in aqueous solution. The modification of luminescence and the sensing capabilities of Pmvb can be accomplished by ClO− and Fe3+ in water and DMSO, respectively, through self-assembly and disassembly process. In the aqueous solution, ClO− has the potential to engage in electrostatic interactions with the positively charged methylpyridine groups of Pmvb, which leads to a notable enhancement in fluorescence emission and a discernible alteration in color, transitioning from dark yellow to bright orange. Interestingly, in DMSO solution, the luminescence suppression of Pmvb in the presence of Fe3+ was observed, accompanied with change of the fluorescence emission color from bright yellow to dark orange, caused by the cation-π interactions between Fe3+ and the pyrene unit of Pmvb. Thus, the specific colorimetric and fluorometric sensor of pyrene derivatives could be achieved by ClO− and Fe3+ in different solvents.

Borosilicate glass as a surface finishing alternative for improving the mechanical properties of third-generation zirconia

ObjectiveThis study evaluated the effect of an experimental borosilicate glass on the mechanical and optical behavior of 5Y-PSZ zirconia and comparing it to commercial glaze and as-sintered. MethodsDisc-shaped specimens of a 5Y-PSZ (Zpex Smile) were prepared and sintered (1550 °C, 2 h). The zirconia discs were randomly divided according to the surface treatment: as-sintered (C), commercial glaze (G), and experimental borosilicate glass (SL). Glaze and experimental glass powders were mixed with building liquids and applied to zirconia with a brush. G specimens were fired at 950 °C and SL at 1200 °C. An extended dwell time of 20 min was applied to both groups. Biaxial flexural strength, roughness (Ra and Rz), translucency (TP00), color alteration (ΔE00), Vickers hardness, fracture toughness, residual stresses, and x-ray diffraction analyses were conducted. Statistical analyses were performed with Weibull statistics, Kruskal-Wallis, or ANOVA tests (α = 5%). ResultsSL yielded the highest flexural strength (799.35 MPa), followed by G (662.34 MPa), and C (485.38 MPa). The fracture origin of SL specimens was in the bulk zirconia, while G and C showed fractures starting at the surface. As-sintered reached the highest fracture toughness and hardness. Glaze and borosilicate glass provided surface compressive stresses. Borosilicate glass application led to phase transformation (t→m). SL and G showed the lowest roughness. TP00 and ΔE00 were similar among groups. SignificanceBorosilicate glass improved strength without harming the optical properties of third-generation zirconia. Toughness and roughness provided by the experimental glass were similar to those from commercial glaze.

PH-sensitive films based on carboxymethyl cellulose/date pits anthocyanins: A convenient colorimetric indicator for beef meat freshness tracking

The pH-sensitive intelligent film is a much-awaited advancement in packaging technology, which uses visually discernible color changes to warn consumers about the freshness or spoilage of perishable food products. This study aims to develop an intelligent indicating film based on carboxymethyl cellulose (CMC), formulated with date pits anthocyanins-rich extract (DPAE) at 1.5 %. The incorporation of DPAE significantly enhanced the physical (moisture content, swelling index, water solubility and biodegradability) and mechanical (thickness, elongation at break and thickness). Developed films exhibited a higher antioxidant and antibacterial activity against food-borne pathogens. Furthermore, the inclusion of DPAE had a noticeable effect on pH-sensitive characteristics of the CMC/DPAE films. Interestingly, the CMC/DPAE film displayed a color change from yellow to dark brownish in response to changes in pH levels, covering a wide range from 1 to 13. The CMC/DPAE films were also capable of detecting ammonia at concentrations ranging from 0.125 to 1 mg/mL. In order to monitor the freshness of minced beef meat stored under refrigerated conditions at 4 °C over 14 days, CMC/DPAE films exhibited noticeable color variations corresponding to the changes in meat quality, which were assessed based on total volatile basic nitrogen, microbial count, and pH during storage. The color alteration on the packaging label shifted from yellow to dark, signifying changes in meat freshness. The obtained results stipulated that the newly developed CMC/DPAE films hold promise as innovative colorimetric pH indicators for tracking the freshness and spoilage meat-products in the food industry and supermarkets.

Fluorescence and pectinase double-triggered chitosan/pectin/calcium propionate/curcumin-β-cyclodextrin complex film for pork freshness monitoring and maintenance

An intelligent and active food packaging film based on chitosan (CS), pectin (P), calcium propionate (CP), and curcumin-β-cyclodextrin complex (Cur-β-CD) was prepared. The CS/P/CP/Cur-β-CD film exhibited improved hydrophobicity (74.78 ± 0.53°), water vapor (4.55 ± 0.16 × 10−11 g·(m·s·Pa)−1), and oxygen (1.50 ± 0.06 × 10−12 g·(m·s·Pa)−1) barrier properties, as well as antioxidant (72.34 ± 3.79 % for DPPH and 86.05 ± 0.14 % for ABTS) and antibacterial (79.41 ± 2.89 % for E. coli and 83.82 ± 3.96 % for S. aureus) activities. The release of CP and Cur could be triggered by pectinase, with their cumulative release reaching 92.62 ± 1.20 % and 42.24 ± 1.15 %, respectively. The CS/P/CP/Cur-β-CD film showed delayed alterations in surface color, pH value, total volatile bases nitrogen, total viable counts, thiobarbituric acid reactive substance, hardness, and springiness of pork. Additionally, the fluorescence intensity of the film gradually decreased. In conclusion, we have developed a pH-responsive film with pectinase-triggered release function, providing a new concept for the design of multi-signal responsive intelligent food packaging.

Phenazine-based fluorescence probes for simultaneous sensing of silver and iodide ions

The selective and sensitive detection of silver ions (Ag+) and iodide ions (I−) is of paramount importance in various scientific and industrial domains. In this paper, we present phenazine-based fluorescence probes, synthesized through a scalable and straightforward procedure, for the simultaneous sensing of Ag+ and I−ions in solution phase. The introduction of Ag+ led to ratiometric changes, manifesting in alterations of both solution color (from colorless to yellow) and fluorescence signal (from blue to cyan). Mechanistic investigations unveil that Ag+ coordinate with the phenazine nitrogen ends, forming self-assembled nanostructures characterized by significant charge-transfer properties. Moreover, we observed that the nature of the terminal alkyl residue played a pivotal role in governing the binding interaction with Ag+, with aliphatic residues featuring positively charged quaternary nitrogen ends exhibiting notably reduced responses. Additionally, the in-situ formed metal complex, comprising 1.Ag+, proved to be highly effective in selectively analyzing I− ions. The exceptional binding affinity of Ag+ for I− ions, marked by an exceptionally low solubility product constant, facilitated the sequestration of Ag+, ultimately leading to the formation of free probe in the reaction medium. Our research showcases the capability of phenazine-based probes in selective ion sensing applications, and their adjustable properties position them as promising options for a range of analytical and diagnostic uses.

Is the whitening effect of charcoal-based dentifrices related to their abrasive potential or the ability of charcoal to adsorb dyes?

ObjectivesTo evaluate if tooth color alteration of activated charcoal-based dentifrices may be attributed to the dye adsorption potential of charcoal (chemical action - C - slurry only) or to the association of dye adsorption with abrasion (chemo-mechanical action - CM- slurry/toothbrushing). Potential adverse effects in surface roughness, gloss, and wear were also assessed. MethodsBovine enamel/dentin specimens were randomly allocated into the groups according to treatments and test model (n = 15): deionized water (negative control- NC); Colgate Maximum Anticaries Protection (conventional toothpaste- positive control- PC); Colgate Luminous White Activated Charcoal (LW); Oral-B 3D White Therapy Charcoal (WT); Curaprox Black is White (BW); Dermavita Whitemax (Activated charcoal powder- WP). Specimens were exposed to the C or CM models, in 28-day staining-treatment cycling. Color change (ΔE00), whiteness index (ΔWID), percentage of alteration of surface roughness (%Raalt), and gloss (%GUalt) were calculated. Additional specimens (n = 9) were indented with a Knoop diamond and subjected to 100,000 abrasion cycles. Enamel wear was determined by calculating the decrease in indentations geometry. Data were analyzed by ANOVA/Tukey tests (α = 0.05). ResultsThe CM-model produced lower color change (staining) than C (p = 0.0001). PC, LW, WT, BW, and WP showed similar color results for both models, differing from NC (p < 0.05).%Ra and%GU did not differ among the C-model groups (p > 0.05) and WP exhibited the highest variation (%Ra and%GU) under CM-model. Enamel wear values were lowest in the NC and PC groups, intermediate for LW, WT, BW, and highest for the WP (p < 0.05). ConclusionActivated charcoal-based dentifrices have a similar ability to minimize tooth staining as the conventional toothpaste, with increased enamel wear potential in the long term (after 100,000 cycles). The activated charcoal powder damaged the enamel surface, showing a higher deleterious effect on enamel roughness, gloss, and wear. Clinical significanceDentifrices containing activated charcoal do not provide superior results to minimize tooth staining compared to conventional toothpaste. Charcoal powder should be used with caution because it promotes higher superficial alterations on the enamel surface.

Thin colorimetric film array for rapid and selective detection of v-type nerve agent mimic in potentially contaminated areas

The expeditious detection and quantification of V-series nerve agents (VX) on potentially contaminated surfaces are crucial for the prevention of regional conflict incidents, acts of terrorism, or illicit activities. However, the low volatility and high toxicity of VX make these tasks challenging. Herein, we designed two novel colorimetric thin polymeric films to rapidly and sensitively detect demeton-S, a VX mimic, in contaminated areas. The polymeric films were specifically engineered to include a coordination site for Au (III) ions. Initially, these films were coordinated with Au (III), causing a discernible alteration in color due to enhancement in intramolecular charge transfer process. In the presence of demeton-S, the Au (III) ligands in the films are displaced with demeton-S, resulting in the restoration of the original color of the film, as the enhanced intramolecular charge transfer process is inhibited and thereby serving as an indicator of the presence of demeton-S. The polymeric films exhibit remarkable selectivity toward demeton-S compared to G-type nerve agents and other interference. The reusability of the polymeric films for demeton-S detection was achieved owing to the reversibility of the films during the alternative exposure of Au (III) and demeton-S. The polymeric films demonstrated their applicability for demeton-S detection and quantification in several contaminated areas, including different water, soil, and skin, rendering them highly suitable for on-site measurements.

Smart packaging films based on corn starch/polyvinyl alcohol containing nano SIM-1 for monitoring food freshness

There is at present an acute need for the construction of biopolymer-based smart packaging material that can be applied for the real-time visual monitoring of food freshness. Herein, a nano-sized substituted imidazolate material (SIM-1) with ammonia-sensitive and antibacterial ability was effectively manufactured and then anchored within corn starch/polyvinyl alcohol (CS/PVA) blend to construct biopolymeric smart active packaging material. The structure, physical and functional performances of CS/PVA-based films with different content of SIM-1 (0.5, 1.0 and 2.0 wt% on CS/PVA basis) were then explored in detail. Results revealed that the incorporated SIM-1 nanocrystals were equally anchored within the CS/PVA matrix owing to the establishment of potent hydrogen-bonding interactions, which produced an obvious improvement in the compatibility of CS/PVA blend film, as well as its mechanical strength, water/oxygen barrier and UV-screening performances. The constructed CS/PVA/SIM-1 blend films further demonstrated superior long-term color stability property, ammonia-sensitive and antibacterial functions. Furthermore, the CS/PVA/SIM-1 blend films were utilized for effectively monitoring the deterioration of shrimp via observable color alteration. The above findings suggested the potential applications of CS/PVA/SIM-1 blend films in smart active packaging.