Displaying publications 1 - 20 of 68 in total

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  1. Ramanathan S, Parthasarathy S, Murugaiyah V, Magosso E, Tan SC, Mansor SM
    Molecules, 2015 Mar 18;20(3):4915-27.
    PMID: 25793541 DOI: 10.3390/molecules20034915
    Varied pharmacological responses have been reported for mitragynine in the literature, but no supportive scientific explanations have been given for this. These studies have been undertaken without a sufficient understanding of the physicochemical properties of mitragynine. In this work a UV spectrophotometer approach and HPLC-UV method were employed to ascertain the physicochemical properties of mitragynine. The pKa of mitragynine measured by conventional UV (8.11 ± 0.11) was in agreement with the microplate reader determination (8.08 ± 0.04). Mitragynine is a lipophilic alkaloid, as indicated by a logP value of 1.73. Mitragynine had poor solubility in water and basic media, and conversely in acidic environments, but it is acid labile. In an in vitro dissolution the total drug release was higher for the simulated gastric fluid but was prolonged and incomplete for the simulated intestinal fluid. The hydrophobicity, poor water solubility, high variability of drug release in simulated biological fluids and acid degradable characteristics of mitragynine probably explain the large variability of its pharmacological responses reported in the literature. The determined physicochemical properties of mitragynine will provide a basis for developing a suitable formulation to further improve its solubility, stability and oral absorption for better assessment of this compound in preclinical studies.
  2. Whittam DH, Karthikeayan V, Gibbons E, Kneen R, Chandratre S, Ciccarelli O, et al.
    J Neurol, 2020 Dec;267(12):3565-3577.
    PMID: 32623595 DOI: 10.1007/s00415-020-10026-y
    INTRODUCTION: While monophasic and relapsing forms of myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) are increasingly diagnosed world-wide, consensus on management is yet to be developed.

    OBJECTIVE: To survey the current global clinical practice of clinicians treating MOGAD.

    METHOD: Neurologists worldwide with expertise in treating MOGAD participated in an online survey (February-April 2019).

    RESULTS: Fifty-two responses were received (response rate 60.5%) from 86 invited experts, comprising adult (78.8%, 41/52) and paediatric (21.2%, 11/52) neurologists in 22 countries. All treat acute attacks with high dose corticosteroids. If recovery is incomplete, 71.2% (37/52) proceed next to plasma exchange (PE). 45.5% (5/11) of paediatric neurologists use IV immunoglobulin (IVIg) in preference to PE. Following an acute attack, 55.8% (29/52) of respondents typically continue corticosteroids for ≥ 3 months; though less commonly when treating children. After an index event, 60% (31/51) usually start steroid-sparing maintenance therapy (MT); after ≥ 2 attacks 92.3% (48/52) would start MT. Repeat MOG antibody status is used by 52.9% (27/51) to help decide on MT initiation. Commonly used first line MTs in adults are azathioprine (30.8%, 16/52), mycophenolate mofetil (25.0%, 13/52) and rituximab (17.3%, 9/52). In children, IVIg is the preferred first line MT (54.5%; 6/11). Treatment response is monitored by MRI (53.8%; 28/52), optical coherence tomography (23.1%; 12/52) and MOG antibody titres (36.5%; 19/52). Regardless of monitoring results, 25.0% (13/52) would not stop MT.

    CONCLUSION: Current treatment of MOGAD is highly variable, indicating a need for consensus-based treatment guidelines, while awaiting definitive clinical trials.

  3. Murugasenapathi NK, Ghosh R, Ramanathan S, Ghosh S, Chinnappan A, Mohamed SAJ, et al.
    Crit Rev Anal Chem, 2023;53(5):1044-1065.
    PMID: 34788167 DOI: 10.1080/10408347.2021.2002133
    Transistor-based sensors have been widely recognized to be highly sensitive and reliable for point-of-care/bed-side diagnosis. In this line, a range of cutting-edge technologies has been generated to elevate the role of transistors for biomolecule detection. Detection of a wide range of clinical biomarkers has been reported using various configurations of transistors. The inordinate sensitivity of transistors to the field-effect imparts high sensitivity toward wide range of biomolecules. This overview has gleaned the present achievements with the technological advancements using high performance transistor-based sensors. This review encloses transistors incorporated with a variety of functional nanomaterials and organic elements for their excellence in selectivity and sensitivity. In addition, the technological advancements in fabrication of these microdevices or nanodevices and functionalization of the sensing elements have also been discussed. The technological gap in the realization of sensors in transistor platforms and the resulted scope for research has been discussed. Finally, foreseen technological advancements and future research perspectives are described.
  4. Kamilla, L., Ramanathan, S., Sasidharan, S., Mansor, S.M.
    MyJurnal
    The Clitoria ternatea (Fabaceae) root, seed, and leaf are commonly used in Ayurvedic medicine in Malaysia and Indonesia. The methanol leaf extracts of C. ternatea was tested for toxicity by means of brine shrimp lethality test and acute oral toxicity assay. In the brine shrimp lethality test, the leaf extract were non-toxic or showed weak lethality (LC50 > 1 mg/ml) at the 6 h, 12 h and 24 h incubation period. Nevertheless, at the 48 h incubation time, the leaf extract exhibited moderate toxicity activity with LC50 values of 0.49 mg/ml. In the acute toxicity study using mice, the median lethal dose (LD50) of the extract was found greater than 2000 mg/kg, and we found no pathological changes by means of macroscopic examination of tissues of mice treated with the extract. We conclude that the C. ternatea leaf extract is not toxic in mice and brine shrimp.
  5. Navaratnam V, Ramanathan S, Wahab MS, Siew Hua G, Mansor SM, Kiechel JR, et al.
    Eur J Clin Pharmacol, 2009 Aug;65(8):809-21.
    PMID: 19404632 DOI: 10.1007/s00228-009-0656-1
    There is limited pharmacokinetic data available for the combination artesunate + amodiaquine, which is used widely to treat uncomplicated malaria. This study examines the bioavailability and tolerability of a fixed (200 mg artesunate + 540 mg amodiaquine) and loose (200 mg + 612 mg) combination with a 2x2 cross-over design in 24 healthy volunteers.
  6. Sathasivam K, Ramanathan S, Mansor SM, Haris MR, Wernsdorfer WH
    Wien Klin Wochenschr, 2009 Oct;121 Suppl 3:19-22.
    PMID: 19915811 DOI: 10.1007/s00508-009-1229-0
    Following up a popular use of crude leaf preparations from Carica papaya for the treatment of dengue infections, a suspension of powdered Carica papaya leaves in palm oil has been investigated for its effect on thrombocyte counts in mice, administering by gavage 15 mg of powdered leaves per kg body weight to 5 mice. Equal numbers of animals received corresponding volumes of either palm oil alone or physiological saline solution. Thrombocyte counts before and at 1, 2, 4, 8, 10, 12, 24, 48 and 72 hours after dosing revealed significantly higher mean counts at 1, 2, 4, 8, 10 and 12 after dosing with the C. papaya leaf formulation as compared to the mean count at hour 0. There was only a non-significant rise of thrombocyte counts in the group having received saline solution, possibly the expression of a normal circadian rhythm in mice. The group having received palm oil only showed a protracted increase of platelet counts that was significant at hours 8 and 48 and obviously the result of a hitherto unknown stimulation of thrombocyte release. The results call for a dose-response investigation and for extending the studies to the isolation and identification of the C. papaya substances responsible for the release and/or production of thrombocytes.
  7. Alagasamy SV, Ramanathan S, Chear NJ, Tan WN, Ramachandram DS, Ching-Ga AT, et al.
    J Complement Integr Med, 2021 Jan 01;18(2):339-345.
    PMID: 34187118 DOI: 10.1515/jcim-2019-0316
    OBJECTIVES: Mesua ferrae, from the family of Calophyllaceae, is traditionally used for the treatment of piles, fever and renal disorders. The present study was aimed to examine the antibacterial compounds from the leaves of M. ferrae and their β-lactam antibiotic potentiate activities against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA).

    METHODS: Stigmasterol (1) and β-caryophyllene oxide (2) were isolated from the n-hexane fraction of the leaves of M. ferrae using a bioassay-guided fractionation approach.

    RESULTS: The isolated compounds displayed anti-Staphylococcus and anti-MRSA activities. It is worth to note that both compounds demonstrated synergism with β-lactam antibiotics against S. aureus and MRSA. Gas chromatography-mass spectrometry (GC-MS) analysis indicated the n-hexane fraction was dominated by triterpenes and sesquiterpenes, suggesting the total antibacterial activity exhibited by the fraction.

    CONCLUSION: Based on the findings, it could conclude that M. ferrae is a promising natural source for the discovery of new anti-MRSA lead compounds.

  8. Sabetghadam A, Ramanathan S, Mansor SM
    Pharmacognosy Res, 2010 May;2(3):181-5.
    PMID: 21808563 DOI: 10.4103/0974-8490.65514
    Mitragyna speciosa Korth is a medicinal plant indigenous to Thailand and Malaysia and has been known for its narcotic and coca-like effects. Many studies have been performed on the antinociceptive effect of the plant extracts of Thai origin; however, limited studies have been reported till date on M. speciosa extracts of Malaysian origin. Various concentrations of alkaloid (5-20 mg/kg), methanolic (50-200 mg/kg), and aqueous (100-400 mg/kg) extracts of Malaysian M. speciosa leaves were prepared and orally administered to nine groups of rats. Morphine (5 mg/kg, s.c.) and aspirin (300 mg/kg, p.o.) were used as control. Antagonism of the antinociceptive activity was evaluated by pretreatment with naloxone at a dose of 2 mg/kg (i.p.). Results showed that oral administration of the alkaloid (20 mg/kg), methanolic (200 mg/kg), and aqueous (400 mg/kg) extracts significantly prolonged the latency of nociceptive response compared with control groups in both hot plate and tail flick tests (P < 0.05). Antinociceptive action of the alkaloid (20 mg/kg), methanolic (200 mg/kg), and aqueous (400 mg/kg) extracts was significantly blocked by naloxone. In conclusion, these results suggest the presence of antinociceptive effect in various extracts of Malaysian M. speciosa leaves. In addition, the antinociceptive effective doses vary depending on the type of solvents used for extraction.
  9. Yahya MM, Ismail MP, Ramanathan S, Kadir MN, Azhar A, Ibrahim NBC, et al.
    Biomedicines, 2023 Feb 11;11(2).
    PMID: 36831061 DOI: 10.3390/biomedicines11020525
    Breast carcinoma is the most common cancer of women in Malaysia. The most common sites of metastasis are the lung, liver, bone and brain. A 45-year-old lady was diagnosed with left invasive breast carcinoma stage IV (T4cN1M1) with axillary lymph nodes and lung metastasis. She was noted to have a cervical mass through imaging, and biopsy showed CIN III. Post chemotherapy, the patient underwent left simple mastectomy with examination under anaesthesia of the cervix, cystoscopy and staging. The cervical histopathological examination (HPE) showed squamous cell carcinoma, and clinical staging was 2A. The breast tissue HPE showed invasive carcinoma with triple receptors positivity. The patient was given tamoxifen and put on concurrent chemoradiotherapy (CCRT) for the cervical cancer. The management of each pathology of this patient involved a multi-disciplinary team that included surgeons, oncologists, gynaecologists, pathologists and radiologists. Due to the complexity of the case with two concurrent cancers, the gene expression profiles may help predict the patient's clinical outcome.
  10. Sabetghadam A, Ramanathan S, Sasidharan S, Mansor SM
    J Ethnopharmacol, 2013 Apr 19;146(3):815-23.
    PMID: 23422336 DOI: 10.1016/j.jep.2013.02.008
    ETHNOPHARMACOLOGICAL RELEVANCE: Mitragyna speciosa is a popular medicinal plant in Southeast Asia which is commonly used for its morphine-like effects. Although the analgesic properties of Mitragyna speciosa and its ability to ameliorate withdrawal signs after abrupt cessation of opioid abuse are well known, information about the long-term safety of the plant's active compounds is lacking. In this work, we evaluated the effects of sub-chronic exposure to mitragynine, the principal alkaloid of Mitragyna speciosa leaves in rats.

    MATERIALS AND METHODS: Male and female Sprague-Dawley rats received three doses of mitragynine (1, 10, 100mg/kg, p.o) for 28 days respectively. Food intake and relative body weight were measured during the experiment. After completion of drug treatment biochemical, hematological, and histological analyses were performed.

    RESULTS: No mortality was observed in any of the treatment groups. The groups of rats treated with the lower and intermediate doses showed no toxic effects during the study. However, the relative body weight of the group of female rats treated with the 100mg/kg dose was decreased significantly. Food intake also tended to decrease in the same group. Only relative liver weight increased after treatment with the high dose of mitragynine (100mg/ kg) in both the male and female treatment groups of rats. Biochemical and hematological parameters were also altered especially in high dose treatment group which corresponds to the histopathological changes.

    CONCLUSIONS: The study demonstrated that mitragynine is relatively safe at lower sub-chronic doses (1-10mg/kg) but exhibited toxicity at a highest dose (sub-chronic 28 days: 100mg/kg). This was confirmed by liver, kidney, and brain histopathological changes, as well as hematological and biochemical changes.

  11. Sharma A, Kamble SH, León F, Chear NJ, King TI, Berthold EC, et al.
    Drug Test Anal, 2019 Aug;11(8):1162-1171.
    PMID: 30997725 DOI: 10.1002/dta.2604
    Kratom (Mitragyna speciosa) is a psychoactive plant popular in the United States for the self-treatment of pain and opioid addiction. For standardization and quality control of raw and commercial kratom products, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the quantification of ten key alkaloids, namely: corynantheidine, corynoxine, corynoxine B, 7-hydroxymitragynine, isocorynantheidine, mitragynine, mitraphylline, paynantheine, speciociliatine, and speciogynine. Chromatographic separation of diastereomers, or alkaloids sharing same ion transitions, was achieved on an Acquity BEH C18 column with a gradient elution using a mobile phase containing acetonitrile and aqueous ammonium acetate buffer (10mM, pH 3.5). The developed method was linear over a concentration range of 1-200 ng/mL for each alkaloid. The total analysis time per sample was 22.5 minutes. The analytical method was validated for accuracy, precision, robustness, and stability. After successful validation, the method was applied for the quantification of kratom alkaloids in alkaloid-rich fractions, ethanolic extracts, lyophilized teas, and commercial products. Mitragynine (0.7%-38.7% w/w), paynantheine (0.3%-12.8% w/w), speciociliatine (0.4%-12.3% w/w), and speciogynine (0.1%-5.3% w/w) were the major alkaloids in the analyzed kratom products/extracts. Minor kratom alkaloids (corynantheidine, corynoxine, corynoxine B, 7-hydroxymitragynine, isocorynantheidine) were also quantified (0.01%-2.8% w/w) in the analyzed products; however mitraphylline was below the lower limit of quantification in all analyses.
  12. Singh D, Narayanan S, Vicknasingam BK, Prozialeck WC, Ramanathan S, Zainal H, et al.
    J Psychoactive Drugs, 2018 03 20;50(3):266-274.
    PMID: 29558272 DOI: 10.1080/02791072.2018.1443234
    Kratom (Mitragyna speciosa Korth.) is traditionally used in Southeast Asia for its medicinal value and psychoactive properties. Nonetheless, cessation from regular kratom use is reported to cause unpleasant dose-dependent withdrawal symptoms. This study aims to evaluate the severity of pain and sleep problems following the cessation of kratom tea/juice consumption among regular kratom users. A total of 170 regular users were recruited through snowball sampling for this cross-sectional study. The Brief Pain Inventory (BPI) and Pittsburgh Sleep Quality Index (PSQI) scales were administered to assess the severity of pain and sleep problems. Most participants experienced moderate pain intensity (84%) and moderate pain interference (70%) during kratom cessation; 46% experienced more sleep problems during kratom cessation. Individuals who consumed ≥4 glasses of kratom tea/juice (about 76-115 mg of mitragynine) daily had higher odds of reporting some pain interference (OR: 2.0; CI: 1.04-3.93: p 
  13. Khaw KY, Kumar P, Yusof SR, Ramanathan S, Murugaiyah V
    Arch Pharm (Weinheim), 2020 Nov;353(11):e2000156.
    PMID: 32716578 DOI: 10.1002/ardp.202000156
    α-Mangostin has been reported to possess a broad range of pharmacological effects including potent cholinesterase inhibition, but the development of α-mangostin as a potential lead compound is impeded by its toxicity. The present study investigated the impact of simple structural modification of α-mangostin on its cholinesterase inhibitory activities and toxicity toward neuroblastoma and liver cancer cells. The dialkylated derivatives retained good acetylcholinesterase (AChE) inhibitory activities with IC50 values between 4.15 and 6.73 µM, but not butyrylcholinesterase (BChE) inhibitory activities, compared with α-mangostin, a dual inhibitor (IC50 : AChE, 2.48 µM; BChE, 5.87 µM). Dialkylation of α-mangostin produced AChE selective inhibitors that formed hydrophobic interactions at the active site of AChE. Interestingly, all four dialkylated derivatives of α-mangostin showed much lower cytotoxicity, being 6.4- to 9.0-fold and 3.8- to 5.5-fold less toxic than their parent compound on neuroblastoma and liver cancer cells, respectively. Likewise, their selectivity index was higher by 1.9- to 4.4-fold; in particular, A2 and A4 showed improved selectivity index compared with α-mangostin. Taken together, modification of the hydroxyl groups of α-mangostin at positions C-3 and C-6 greatly influenced its BChE inhibitory and cytotoxic but not its AChE inhibitory activities. These dialkylated derivatives are viable candidates for further structural modification and refinement, worthy in the search of new AChE inhibitors with higher safety margins.
  14. Tang SGH, Hadi MHH, Arsad SR, Ker PJ, Ramanathan S, Afandi NAM, et al.
    Int J Environ Res Public Health, 2022 Oct 11;19(20).
    PMID: 36293576 DOI: 10.3390/ijerph192012997
    Since the year 2020, coronavirus disease 2019 (COVID-19) has emerged as the dominant topic of discussion in the public and research domains. Intensive research has been carried out on several aspects of COVID-19, including vaccines, its transmission mechanism, detection of COVID-19 infection, and its infection rate and factors. The awareness of the public related to the COVID-19 infection factors enables the public to adhere to the standard operating procedures, while a full elucidation on the correlation of different factors to the infection rate facilitates effective measures to minimize the risk of COVID-19 infection by policy makers and enforcers. Hence, this paper aims to provide a comprehensive and analytical review of different factors affecting the COVID-19 infection rate. Furthermore, this review analyses factors which directly and indirectly affect the COVID-19 infection risk, such as physical distance, ventilation, face masks, meteorological factor, socioeconomic factor, vaccination, host factor, SARS-CoV-2 variants, and the availability of COVID-19 testing. Critical analysis was performed for the different factors by providing quantitative and qualitative studies. Lastly, the challenges of correlating each infection risk factor to the predicted risk of COVID-19 infection are discussed, and recommendations for further research works and interventions are outlined.
  15. Ponnusamy Y, Chear NJ, Ramanathan S, Lai CS
    J Ethnopharmacol, 2015 Jun 20;168:305-14.
    PMID: 25858509 DOI: 10.1016/j.jep.2015.03.062
    Dicranopteris linearis is a fern used traditionally for the treatment of skin afflictions such as external wounds, boils and ulcers. However, there are no scientific studies to date to demonstrate its ability to induce wound recovery. The objective of the present study was to explore the wound healing properties of an active fraction of D. linearis through several in vitro assays and to determine its chemical profile.
  16. Sahgal G, Ramanathan S, Sasidharan S, Mordi MN, Ismail S, Mansor SM
    Trop Biomed, 2009 Dec;26(3):274-9.
    PMID: 20237441 MyJurnal
    The present study was designed to evaluate the antibacterial activities of Swietenia mahagoni crude methanolic (SMCM) seed extract. The antimicrobial activity of the oily extract against Gram-positive, Gram-negative, yeast and fungus strains was evaluated based on the inhibition zone using disc diffusion assay, minimal inhibition concentration (MIC) and minimal bactericidal concentration (MBC) values. The crude extract was subjected to various phytochemicals analysis. The demonstrated qualitative phytochemical tests exhibited the presences of common phytocompounds including alkaloids, terpenoids, antraquinones, cardiac glycosides, saponins, and volatile oils as major active constituents. The SMCM seed extract had inhibitory effects on the growth of Candida albicans, Staphylococcus aureus, Pseudomonas aeroginosa, Streptococcus faecalis and Proteus mirabillase and illustrated MIC and MBC values ranging from 25 mg/ml to 50 mg/ml.
  17. Venkatesh G, Ramanathan S, Nair NK, Mansor SM, Sattar MA, Khan MA, et al.
    Biomed Chromatogr, 2007 May;21(5):484-90.
    PMID: 17294505
    A simple and sensitive RP-HPLC-UV method was developed and validated for simultaneous determination of atenolol and propranolol and subsequently applied to investigate the effect of dimethyl sulfoxide in rat in situ intestinal permeability studies. Atenolol (400 microm) and propranolol (100 microm) were perfused in the small intestine of anaesthetized (pentobarbitone sodium 60 mg/kg, i.p.) male Sprague-Dawley rats either in the presence (1, 3 and 5%) or in the absence of dimethyl sulfoxide. There was no significant alteration (p > 0.05) in the permeability of atenolol and propranolol, which indicated there was no effect of various concentrations of dimethyl sulfoxide (1-5%) on the membrane integrity of the rat intestinal tissues. The analytical method was validated on a C(4) column with a mobile phase comprising ammonium acetate buffer (pH 3.5, 0.02 m) and acetonitrile in the ratio of 30:70 (v/v) at a flow rate of 1.0 mL/min. The validated method was found to be accurate and precise and stability studies were carried out at different storage conditions and both analytes were found to be stable. These findings are applicable for determining the absorbability of water-insoluble drugs and new chemical entities for the purpose of classifying them in the biopharmaceutical classification system.
  18. Venkatesh G, Majid MI, Ramanathan S, Mansor SM, Nair NK, Croft SL, et al.
    Biomed Chromatogr, 2008 May;22(5):535-41.
    PMID: 18205140 DOI: 10.1002/bmc.965
    A simple, sensitive and specific reversed-phase high-performance liquid chromatographic method with UV detection at 251 nm was developed for quantitation of buparvaquone (BPQ) in human and rabbit plasma. The method utilizes 250 microL of plasma and sample preparation involves protein precipitation followed by solid-phase extraction. The method was validated on a C18 column with mobile phase consisting of ammonium acetate buffer (0.02 m, pH 3.0) and acetonitrile in the ratio of 18:82 (v/v) at a flow rate of 1.1 mL/min. The calibration curves were linear (correlation coefficient>or=0.998) in the selected range. The method is specific and sensitive with limit of quantitation of 50 ng/mL for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and BPQ was found to be stable. Partial validation studies were carried out using rabbit plasma and intra- and inter-day precision and accuracy were within 7%. This method is simple, reliable and can be routinely used for preclinical pharmacokinetic studies for BPQ.
  19. Ramanathan S, Gopinath SCB, Md Arshad MK, Poopalan P
    Biosens Bioelectron, 2019 Sep 15;141:111434.
    PMID: 31238281 DOI: 10.1016/j.bios.2019.111434
    The pragmatic outcome of a lung cancer diagnosis is closely interrelated in reducing the number of fatal death caused by the world's top cancerous disease. Regardless of the advancement made in understanding lung tumor, and its multimodal treatment, in general the percentage of survival remain low. Late diagnosis of a cancerous cell in patients is the major hurdle for the above circumstances. In the new era of a lung cancer diagnosis with low cost, portable and non-invasive clinical sampling, nanotechnology is at its inflection point where current researches focus on the implementation of biosensor conjugated nanomaterials for the generation of the ideal sensing. The present review encloses the superiority of nanomaterials from zero to three-dimensional nanostructures in its discrete and nanocomposites nanotopography on sensing lung cancer biomarkers. Recent researches conducted on definitive nanomaterials and nanocomposites at multiple dimension with distinctive physiochemical property were focused to subside the cases associated with lung cancer through the development of novel biosensors. The hurdles encountered in the recent research and future preference with prognostic clinical lung cancer diagnosis using multidimensional nanomaterials and its composites are presented.
  20. Krishnan H, Gopinath SCB, Md Arshad MK, Zulhaimi HI, Ramanathan S
    Mikrochim Acta, 2021 03 31;188(4):144.
    PMID: 33791872 DOI: 10.1007/s00604-021-04794-1
    A conventional photolithography technique was used to fabricate three types of Archimedean-spiral interdigitated electrodes (AIDEs) containing concentric interlocking electrodes with different electrode and gap sizes, i.e., 150 μm (D1), 100 μm (D2), and 50 μm (D3). The precision of the fabrication was validated by surface topography using scanning electron microscopy, high power microscopy, 3D-nano profilometry, and atomic force microscopy. These AIDEs were fabricated with a tolerance of ± 6 nm in dimensions. The insignificant current variation at the pico-ampere range for all bare AIDEs further proved the reproducibility of the device. The large gap sized AIDE (D1) is insensitive to acidic medium, whereas D2 and D3 are insensitive to alkali medium. D2 was the best with regard to its electrical characterization. Furthermore, uniformly synthesized molecularly imprinted polymer (MIP) nanoparticles prepared with human blood clotting factor IX and its aptamer were in the size range 140 to 160 nm, attached on the sensing surface and characterized. The average thickness of deposited MIP film was 1.7 μm. EDX data shows the prominent peaks for silicon and aluminum substrates as 61.79 and 22.52%, respectively. The MIP nanoparticles-deposited sensor surface was characterized by applying it in electrolyte solutions, and smooth curves with the current flow were observed at pH lower than 8 and discriminated against alkali media. This study provides a new MIP amalgamated AIDE with nano-gapped fingers enabling analysis of other biomaterials due to its operation in an ideal buffer range.
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