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Effect of Vitamin C supplements on respiratory tract infections: A systematic review and meta-analysis

Keya TA, Leela A, Fernandez K, Habib N, Rashid M

Curr Rev Clin Exp Pharmacol, 2021 Dec 30.
PMID: 34967304 DOI: 10.2174/2772432817666211230100723

BACKGROUND: Respiratory tract infections are a primary cause of illness and mortality over the world.
OBJECTIVE: This study was aimed to investigate the effectiveness of vitamin C supplementation in preventing and treating respiratory tract infections.
METHODS: We used the Cochrane, PubMed, and MEDLINE Ovid databases to conduct our search. The inclusion criteria were placebo-controlled trials. Random effects meta-analyses were performed to measure the pooled effects of vitamin C supplementation on the incidence, severity, and duration of respiratory illness.
RESULTS: We found ten studies that met our inclusion criteria out of a total of 2758. The pooled risk ratio (RR) of developing respiratory illness when taking vitamin C regularly across the study period was 0⸳94 (with a 95% confidence interval of 0⸳87 to 1⸳01) which found that supplementing with vitamin C lowers the occurrence of illness. This effect, however, was statistically insignificant (P= 0⸳09). This study showed that vitamin C supplementation had no consistent effect on the severity of respiratory illness (SMD 0⸳14, 95% CI -0⸳02 to 0⸳30: I2 = 22%, P=0⸳09). However, our study revealed that vitamin C group had a considerably shorter duration of respiratory infection (SMD -0⸳36, 95% CI -0⸳62 to -0⸳09, P = 0⸳01).
CONCLUSION: Benefits of normal vitamin C supplementation for reducing the duration of respiratory tract illness were supported by our meta-analysis findings. Since few trials have examined the effects of therapeutic supplementation, further research is needed in this area.
Fulltext Prediction of Epileptic Seizure by Analysing Time Series EEG Signal Using k-NN Classifier

Hasan MK, Ahamed MA, Ahmad M, Rashid MA

Appl Bionics Biomech, 2017;2017:6848014.
PMID: 28894351 DOI: 10.1155/2017/6848014

Electroencephalographic signal is a representative signal that contains information about brain activity, which is used for the detection of epilepsy since epileptic seizures are caused by a disturbance in the electrophysiological activity of the brain. The prediction of epileptic seizure usually requires a detailed and experienced analysis of EEG. In this paper, we have introduced a statistical analysis of EEG signal that is capable of recognizing epileptic seizure with a high degree of accuracy and helps to provide automatic detection of epileptic seizure for different ages of epilepsy. To accomplish the target research, we extract various epileptic features namely approximate entropy (ApEn), standard deviation (SD), standard error (SE), modified mean absolute value (MMAV), roll-off (R), and zero crossing (ZC) from the epileptic signal. The k-nearest neighbours (k-NN) algorithm is used for the classification of epilepsy then regression analysis is used for the prediction of the epilepsy level at different ages of the patients. Using the statistical parameters and regression analysis, a prototype mathematical model is proposed which helps to find the epileptic randomness with respect to the age of different subjects. The accuracy of this prototype equation depends on proper analysis of the dynamic information from the epileptic EEG.
Fulltext Osteoradionecrosis in Subaxial Cervical Spine - a Rare and Devastating Complication: A Case Report

Rashid MZ, Ariffin MH, Rhani SA, Baharudin A, Ibrahim K

Malays Orthop J, 2017 Nov;11(3):53-55.
PMID: 29326769 MyJurnal DOI: 10.5704/MOJ.1711.005

Osteoradionecrosis, a rare complication of radiation therapy, is a slow progression disease which affects the surrounding structures of spinal components. It essentially weakens the soft tissue and bony configuration and can cause nerve impingement or cord compression. We describe a patient who underwent radiotherapy for thyroid cancer and presented with cervical kyphosis with anterolisthesis of C3/C4 and C4/C5 some 32 years later. We explore the role of anterior and posterior fusion, as well as hyperbaric oxygen therapy in promoting healing.
Molecular prevalence of Anaplasma marginale in ruminants and Rhipicephalus ticks in northern Pakistan

Ali S, Hasan M, Ahmad AS, Ashraf K, Khan JA, Rashid MI

Trop Biomed, 2023 Mar 01;40(1):7-13.
PMID: 37355998 DOI: 10.47665/tb.40.1.005

Anaplasma marginale is the most prevalent tick-borne haemoparasite of cattle and causes huge economic losses to the dairy industry worldwide. This study aimed to determine the occurrence of A. marginale infection in blood and tick samples collected from livestock animals in the districts located in Khyber Pakhtunkhwa (KPK), Pakistan. A total of 184 blood and 370 tick samples were included in this study. It has never been reported that sheep, goats, and cattle in Tank, Ghulam Khan, Birmil and Miran Shah areas were infected with A. marginale. All samples of blood and ticks were collected through random sampling from March 2021 to January 2022 from cattle, sheep and goats and screened through PCR for anaplasmosis by using primer pairs of Anaplasma spp. Three hundred and seventy ticks were collected from infested hosts (120/184, 64.21%). Among the four morphologically identified tick species, the highest occurrence was recorded for Rhipicephalus sanguineus (n=138, 37.29%), followed by Rhipicephalus microplus (n=131, 35.4%), Rhipicephalus annulatus (n=40, 10.81%), Hyalomma anatolicum (n=31, 8.37%), and Hyalomma marginatum (n=30, 8.1%). The occurrence of female tick was highest (n=160, 43.24%), followed by nymphs (n=140, 37.38%) and males ticks (n=70, 18.9%). Among these ticks, A. marginale was detected in female ticks of R. microplus, and R. sanguineus. Molecular identification of A. marginale was confirmed in 120 out of 184 blood samples and 6 out of 74 tick samples. Overall, occurrence of A. marginale in blood and tick samples was found to be 65.21% and 8.1% respectively. Species-wise occurrence in blood samples of goats were 71.11% followed by sheep 68.31% and cattle 50%. Specie-wise occurrence of A. marginale in tick samples of cattle were 12.5% followed by goats 6.89%. The obtained sequence showed similarity with A. marginale reported from Kenya and USA. We report the first PCR based detection of A. marginale infection in blood samples and in R. sanguineus ticks of goats simultaneously.
Gold, Silver, and Palladium Nanoparticles: A Chemical Tool for Biomedical Applications

Yaqoob SB, Adnan R, Rameez Khan RM, Rashid M

Front Chem, 2020;8:376.
PMID: 32582621 DOI: 10.3389/fchem.2020.00376

Herein, the role of metal-based nanoparticles (NPs) in biomedical analysis and the treatment of critical deceases been highlighted. In the world of nanotechnology, noble elements such as the gold/silver/palladium (Au/Ag/Pd) NPs are the most promising emerging trend to design bioengineering materials that could to be employed as modern diagnostic tools and devices to combat serious diseases. NPs are considered a powerful and advanced chemical tool to diagnose and to cure critical ailments such as HIV, cancer, and other types of infectious illnesses. The treatment of cancer is the most significant application of nanotechnology which is based on premature tumor detection and analysis of cancer cells through Nano-devices. The fascinating characteristic properties of NPs-such as high surface area, high surface Plasmon resonance, multi-functionalization, highly stable nature, and easy processing-make them more prolific for nanotechnology. In this review article, the multifunctional roles of Au/Ag/Pd NPs in the field of medical science, the physicochemical toxicity dependent properties, and the interaction mechanism is highlighted. Due to the cytotoxicity of Ag/Au/Pd NPs, the conclusion and future remarks emphasize the need for further research to minimize the toxicity of NPs in the bio-medicinal field.
Fulltext Antiangiogenic activity of sophorolipids extracted from refined bleached deodorized palm olein

Kithur Mohamed S, Asif M, Nazari MV, Baharetha HM, Mahmood S, Yatim ARM, et al.

Indian J Pharmacol, 2019 4 30;51(1):45-54.
PMID: 31031467 DOI: 10.4103/ijp.IJP_312_18

OBJECTIVES: Sophorolipids (SLs) are a group of surface-active glycolipids produced by a type of nonpathogenic yeast Candida bombicola in the presence of vegetable oil through fermentation technology. SLs have shown antitumor activity; however, the mechanism of action underlying the anticancer activity of SLs is poorly understood. This work evaluated the anticancer activity of SLs fermented from palm oil by exploring its antiangiogenic activity.
MATERIALS AND METHODS: The SLs that were fermented and further characterized for their biochemical activities. Cytotoxicity study was performed to assess cytostatic properties. A series of in vitro and ex vivo angiogenesis assay was also carried out. The relative fold change in the expression of p53 mRNA by SLs was also studied.
RESULTS: Altogether, the data show that SLs derived from palm oil fermentation process inhibited neovascularization in the ex vivo tissue segments and also the endothelial cell proliferation between 50% and 65% inhibition as a whole. The palm oil derived SLs also caused downregulation of the suppression level of vascular endothelial growth factor and also upregulate the p53 mRNA level. The analytical studies revealed the presence of high amount of phenolic compounds but with relatively weak antioxidant activity. The gas chromatography-mass spectrometry studies revealed abundant amount of palmitic and oleic acid, the latter an established antiangiogenic agent, and the former being proangiogenic.
CONCLUSION: Therefore, it can be concluded from this study that SLs derived from fermented palm oil have potent antiangiogenic activity which may be attributed by its oleic acid component.
Fulltext Efficacy of combined formulations of fungicides with different modes of action in controlling botrytis gray mold disease in chickpea

Rashid MH, Hossain MA, Kashem MA, Kumar S, Rafii MY, Latif MA

ScientificWorldJournal, 2014;2014:639246.
PMID: 24723819 DOI: 10.1155/2014/639246

Botrytis gray mold (BGM) caused by Botrytis cinerea Pers. Ex. Fr. is an extremely devastating disease of chickpea (Cicer arietinum L.) and has a regional as well as an international perspective. Unfortunately, nonchemical methods for its control are weak and ineffective. In order to identify an effective control measure, six fungicides with different modes of action were evaluated on a BGM susceptible chickpea variety BARIchhola-1 at a high BGM incidence location (Madaripur) in Bangladesh for three years (2008, 2009, and 2010). Among the six fungicides tested, one was protectant [Vondozeb 42SC, a.i. mancozeb (0.2%)], two systemic [Bavistin 50 WP, a.i. carbendazim (0.2%), and Protaf 250EC, propiconazole (0.05%)], and three combination formulations [Acrobat MZ690, dimethomorph 9% + mancozeb 60%, (0.2%); Secure 600 WG, phenomadone + mancozeb (0.2%); and Companion, mancozeb 63% + carbendazim 12% (0.2%)]. The results showed superiority of combination formulations involving both protectant and systemic fungicides over the sole application of either fungicide separately. Among the combination fungicides, Companion was most effective, resulting in the lowest disease severity (3.33 score on 1-9 scale) and the highest increase (38%) of grain yield in chickpea. Therefore, this product could be preferred over the sole application of either solo protectant or systemic fungicides to reduce yield losses and avoid fungicide resistance.
Atypical (symplastic) leiomyoma of the uterus--a case report

Siti-Aishah MA, Noriah O, Malini MN, Zainul-Rashid MR, Das S

Clin Ter, 2011;162(5):447-50.
PMID: 22041803

A 30-year-old, nulliparous woman presented with a history of subfertility. On examination she was found to have uterine fibroid of 28 weeks size of gravid uterus and subsequently laporatomy myomectomy was performed. Multilobulated masses, with diameters ranging from 22 mm to 160 mm were found. Cut sections of the lobulated masses showed whitish whorled cut surface. One of the multilobulated masses had a cystic cavity, measuring 60x50x35 mm(3). Light microscopic findings of the mass with the cystic cavity showed a well-circumscribed cellular tumour composed of cells exhibiting moderate nuclear atypia which were enlarged, nuclei with prominent chromatin clumping and were distributed in areas. Some tumour cells showed large nuclear pseudoinclusions, multinucleated or multilobated tumour giant cells, smudging and few enlarged nucleoli. Mitotic activity was 4 MFs per 10 HPFs. Occasional cells with intracytoplasmic inclusions resembling rhabdoid - like features were seen. There were no atypical mitoses or tumour necroses were noted. Diagnosis of atypical leiomyoma or symplastic leiomyoma was made. Atypical or symplastic leiomyomas are rare in the region of Malaysia and the present case discusses its incidence in younger age, its morphological features along with diagnosis and clinical outcome.
The efficacy of etoricoxib vs mefenamic acid in the treatment of primary dysmenorrhoea: a randomised comparative trial

Nor Azlin MI, Maryasalwati I, Norzilawati MN, Mahdy ZA, Jamil MA, Zainul Rashid MR

J Obstet Gynaecol, 2008 May;28(4):424-6.
PMID: 18604680 DOI: 10.1080/01443610802150051

Dysmenorrhoea is painful menstruation that occurs in 45-72% of all women. This was a prospective randomised study of the efficacy of etoricoxib (Arcoxia) compared with mefenamic acid (Ponstan) in treating primary dysmenorrhoea. All single, sexually inactive women with primary dysmenorrhoea were randomised into two groups (mefenamic acid and etoricoxib) of pain relief and underwent a cross-over study. The success of treatment as evidenced by pain relief, the side-effects and complications were observed and analysed. Some 80% (20 women) had significantly better pain relief with etoricoxib, compared with only 20 per cent in the mefenamic acid group (p = 0.007). Etoricoxib has significantly fewer side-effects compared with mefenamic acid (p = 0.005) with significantly reduced menstrual blood loss (p = 0.025). In conclusion, etoricoxib is a better treatment for primary dysmenorrhoea with better pain relief, less menstrual blood loss and fewer side-effects compared with mefenamic acid.
Misoprostol (alone) in second trimester terminations of pregnancy: as effective as Gemeprost?

Nor Azlin MI, Abdullah HS, Zainul Rashid MR, Jamil MA

J Obstet Gynaecol, 2006 Aug;26(6):546-9.
PMID: 17000504

Gemeprost (Cervagem) has been used widely compared with Misoprostol (Cytotec) alone in second trimester pregnancy termination. This prospective randomised trial was to evaluate the efficacy of intravaginal Misoprostol (alone) and Gemeprost in second trimester termination of pregnancy. A total of 54 women with 27 on each arm were involved. A total of 25 patients (92.6%) in the Misoprostol group and 22 patients (81.5%) in the Gemeprost group delivered within 48 h. The Misoprostol group delivered earlier, although average number of tablets required were similar. The side-effects were not significant between the two groups in fact, but there was more pyrexia in the Gemeprost group (p = 0.004). Misoprostol in second trimester termination of pregnancy is clinically as effective and less costly than the standard regimen of Gemeprost.
Dose response characteristics of polymethacrylic acid gel (PMAAG) for a polymerization-based dosimeter using NMR

Iskandar SM, Elias S, Jumiah H, Asri MT, Masrianis A, Ab Rahman MZ, et al.

Med J Malaysia, 2004 May;59 Suppl B:212-3.
PMID: 15468893

The radiation-response characteristics of polymetharylic acid gel dosimeter prepared with different concentrations of monomer and cross-linker is described in these studies. The dosimeters were prepared under the hypoxic condition in a glove box and were then irradiated with gamma-rays produced by Co-60 radionuclide that was generated at 1.25MeV energy. The irradiation took place at different doses ranged from 0Gy to 19Gy. Due to the radiation activities, chain-reaction polymerisation processes had taken place in the formation of polymethacrylic acid (PMAA) gel, which cause the dose response mechanism increased in the NMR relaxation rates of protons. It has been observed that for higher concentration of monomer and cross-linker, the polymerization rate was increased.
Fulltext Acupressure only as pain relief for patient with multiple drug allergies undergoing oocyte retrieval

Hamid HA, Mustafa KB, Denegama PA, Karim AK, Omar MH, Razi Zainul Rashid M

Taiwan J Obstet Gynecol, 2016 Feb;55(1):140-1.
PMID: 26927269 DOI: 10.1016/j.tjog.2015.02.006
Pharmacological evaluation of nasal delivery of selegiline hydrochloride-loaded thiolated chitosan nanoparticles for the treatment of depression

Singh D, Rashid M, Hallan SS, Mehra NK, Prakash A, Mishra N

Artif Cells Nanomed Biotechnol, 2016 May;44(3):865-77.
PMID: 26042481 DOI: 10.3109/21691401.2014.998824

The aim of the present study was to investigate the propensity of thiolated chitosan nanoparticles (TCNs) to enhance the nasal delivery of selegiline hydrochloride. TCNs were synthesized by the ionic gelation method. The particle size distribution (PDI), entrapment efficiency (EE), and zeta potential of modified chitosan (CS) nanoparticles were found to be 215 ± 34.71 nm, 70 ± 2.71%, and + 17.06 mV, respectively. The forced swim and the tail suspension tests were used to evaluate the anti-depressant activity, in which elevated immobility time was found to reduce on treatment. TCNs seem to be promising candidates for nose-to-brain delivery in the evaluation of antidepressant activity.
Recent prospective of surface engineered Nanoparticles in the management of Neurodegenerative disorders

Singh D, Kapahi H, Rashid M, Prakash A, Majeed AB, Mishra N

Artif Cells Nanomed Biotechnol, 2016 May;44(3):780-91.
PMID: 26107112 DOI: 10.3109/21691401.2015.1029622

Clinically, the therapeutic outcomes in neurodegenerative disorders (NDs) by drug treatment are very limited, and the most insurmountable obstacle in the treatment of NDs is the blood-brain barrier (BBB), which provides the highest level of protection from xenobiotics. A great deal of attention still needs to be paid to overcome these barriers, and surface-engineered polymeric nanoparticles are emerging as innovative tools that are able to interact with the biological system at a molecular level for the desired response. The present review covers the potential importance of surface-structure-engineered nanoparticles to overcome the BBB for good bioavailability, and the evaluation of drug therapy in NDs.
Fulltext Dataset on applying HPMC polymer to improve encapsulation efficiency and stability of the fish oil: In vitro evaluation

Zaidul ISM, Fahim TK, Sahena F, Azad AK, Rashid MA, Hossain MS

Data Brief, 2020 Oct;32:106111.
PMID: 32904423 DOI: 10.1016/j.dib.2020.106111

Data examines the effect of hydroxypropyl methylcellulose (HPMC) HPMC15 cP, and HPMC 5 cP polymer composition on the physicochemical traits of encapsulated oil made using lab scale spray drying (180 °C). The data found showed that the properties of the reconstituted fish oil powder are significantly affected by the polymer's composition and ratio (p < 0.05). In this experiment, powder with the particle sizes below 60 μm was produced and it was observed that HPMC is a good emulsifier for all formulations and the encapsulation efficiency is high with 75.21% for AF1 formulation. It was also observed that the process of fish oil encapsulation employed by HPMC 5 cP produce a more volatile oil powder, while encapsulation with HPMC 15 cP produced a more stable fish oil powder. These finding shows that the utilisation of HPMC as a polymer to encapsulate fish oil can produce a more efficient and stable compound.
Surface-state dependent optical properties of OH-, F-, and H-terminated 4H-SiC quantum dots

Rashid M, Tiwari AK, Goss JP, Rayson MJ, Briddon PR, Horsfall AB

Phys Chem Chem Phys, 2016 Aug 03;18(31):21676-85.
PMID: 27430278 DOI: 10.1039/c6cp03775e

Density functional calculations are performed for OH-, F- and H-terminated 4H-SiC 10-20 Å diameter clusters to investigate the effect of surface species upon the optical absorption properties. H-termination results in a pronounced size-dependent quantum-confinement in the absorption, whereas F- and OH-terminations exhibit much reduced size dependent absorption due to surface states. Our findings are in good agreement with recent experimental studies, and are able to explain the little explored dual-feature photoluminescence spectra of SiC quantum dots. We propose that along with controlling the size, suitable surface termination is the key for optimizing optical properties of 4H-SiC quantum structures, such as might be exploited in optoelectronics, photovoltaics and biological applications.
Fulltext Inadequate water treatment quality as assessed by protozoa removal in Sarawak, Malaysia

Ting Lo N, Abul Bashar Sarker M, Ai Lian Lim Y, Harun-Or-Rashid M, Sakamoto J

Nagoya J Med Sci, 2018 May;80(2):165-174.
PMID: 29915434 DOI: 10.18999/nagjms.80.2.165

Providing safe drinking-water to human civilization is indispensable; it is one of the most cost-effective means of reducing the disease burden of diarrhea. Unfortunately, water supply quality monitoring from public water treatment plants (WTPs) is often neglected or taken for granted. To determine the produced water quality, WTPs in Sarawak, Malaysia were assessed for their protozoa removal ability. A self-administered questionnaire based on the regulations in the Drinking-water Standards for New Zealand (DWSNZ) was developed. Optional 10-liter raw water samples were collected from willing WTPs for the detection of protozoan cysts. Routine physical and microbial testing of WTP parameters were also requested for raw water quality overview. Two of the nine assessed WTPs achieved three log credits in the treatment component, one of which belonged to Peninsular Malaysia. No log credits were obtained in the other tested components for any samples. Most of the WTPs employed "Coagulation, Sedimentation, and Filtration" using rapid gravity filters without enhancement (P < 0.05). Giardia cysts were detected in raw water sources used for treatment, and the geographical location was identified as an influencing factor for raw water quality. There is an urgent requirement for active collaboration and holistic approaches to review existing water management policies and interventions. WTPs in Sarawak did not achieve the log credits required to safeguard the microbial quality of the water supplied; however, only Giardia cysts were detected in 10-liter raw water samples despite routine microbial parameter monitoring showing disturbing contamination levels.
A comprehensive review on contaminants removal from pharmaceutical wastewater by electrocoagulation process

Zaied BK, Rashid M, Nasrullah M, Zularisam AW, Pant D, Singh L

Sci Total Environ, 2020 Jul 15;726:138095.
PMID: 32481207 DOI: 10.1016/j.scitotenv.2020.138095

The pharmaceuticals are emergent contaminants, which can create potential threats for human health and the environment. All the pharmaceutical contaminants are becoming enormous in the environment as conventional wastewater treatment cannot be effectively implemented due to toxic and intractable action of pharmaceuticals. For this reason, the existence of pharmaceutical contaminants has brought great awareness, causing significant concern on their transformation, occurrence, risk, and fate in the environments. Electrocoagulation (EC) treatment process is effectively applied for the removal of contaminants, radionuclides, pesticides, and also harmful microorganisms. During the EC process, an electric current is employed directly, and both electrodes are dissoluted partially in the reactor under the special conditions. This electrode dissolution produces the increased concentration of cation, which is finally precipitated as hydroxides and oxides. Different anode materials usage like aluminum, stainless steel, iron, etc. are found more effective in EC operation for efficient removal of pharmaceutical contaminants. Due to the simple procedure and less costly material, EC method is extensively recognized for pharmaceutical wastewater treatment over further conventional treatment methods. The EC process has more usefulness to destabilize the pharmaceutical contaminants with the neutralization of charge and after that coagulating those contaminants to produce flocs. Thus, the review places particular emphasis on the application of EC process to remove pharmaceutical contaminants. First, the operational parameters influencing EC efficiency with the electroanalysis techniques are described. Second, in this review emerging challenges, current developments and techno-economic concerns of EC are highlighted. Finally, future recommendations and prospective on EC are envisioned.
Fulltext Rice Crop Counting Using Aerial Imagery and GIS for the Assessment of Soil Health to Increase Crop Yield

Hassan SI, Alam MM, Zia MYI, Rashid M, Illahi U, Su'ud MM

Sensors (Basel), 2022 Nov 07;22(21).
PMID: 36366269 DOI: 10.3390/s22218567

Rice is one of the vital foods consumed in most countries throughout the world. To estimate the yield, crop counting is used to indicate improper growth, identification of loam land, and control of weeds. It is becoming necessary to grow crops healthy, precisely, and proficiently as the demand increases for food supplies. Traditional counting methods have numerous disadvantages, such as long delay times and high sensitivity, and they are easily disturbed by noise. In this research, the detection and counting of rice plants using an unmanned aerial vehicle (UAV) and aerial images with a geographic information system (GIS) are used. The technique is implemented in the area of forty acres of rice crop in Tando Adam, Sindh, Pakistan. To validate the performance of the proposed system, the obtained results are compared with the standard plant count techniques as well as approved by the agronomist after testing soil and monitoring the rice crop count in each acre of land of rice crops. From the results, it is found that the proposed system is precise and detects rice crops accurately, differentiates from other objects, and estimates the soil health based on plant counting data; however, in the case of clusters, the counting is performed in semi-automated mode.
Fulltext Enhancement of Temperature Fluorescence Brightness of Zn@Si Core-Shell Quantum Dots Produced via a Unified Strategy

Almomani MS, Ahmed NM, Rashid M, Ali MKM, Akhdar H, Aldaghri O, et al.

Nanomaterials (Basel), 2021 Nov 22;11(11).
PMID: 34835923 DOI: 10.3390/nano11113158

Despite many dedicated efforts, the fabrication of high-quality ZnO-incorporated Zinc@Silicon (Zn@Si) core-shell quantum dots (ZnSiQDs) with customized properties remains challenging. In this study, we report a new record for the brightness enhancement of ZnSiQDs prepared via a unified top-down and bottom-up strategy. The top-down approach was used to produce ZnSiQDs with uniform sizes and shapes, followed by the bottom-up method for their re-growth. The influence of various NH4OH contents (15 to 25 µL) on the morphology and optical characteristics of ZnSiQDs was investigated. The ZnSiQDs were obtained from the electrochemically etched porous Si (PSi) with Zn inclusion (ZnPSi), followed by the electropolishing and sonication in acetone. EFTEM micrographs of the samples prepared without and with NH4OH revealed the existence of spherical ZnSiQDs with a mean diameter of 1.22 to 7.4 nm, respectively. The emission spectra of the ZnSiQDs (excited by 365 nm) exhibited bright blue, green, orange-yellow, and red luminescence, indicating the uniform morphology related to the strong quantum confinement ZnSiQDs. In addition, the absorption and emission of the ZnSiQDs prepared with NH4OH were enhanced by 198.8% and 132.6%, respectively. The bandgap of the ZnSiQDs conditioned without and with NH4OH was approximately 3.6 and 2.3 eV, respectively.

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