• Journal of Biomedical Engineering Research
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• v.44 no.6
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• pp.404-413
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• 2023

In this research, we studied the development of a SUS304 microneedle array based on microfabrication technology and the applicability of Parylene-C thin film, a medical polymer material. First of all, four materials commonly used in the field of medical engineering (SUS304, Ti, PMMA, and PEEK) were selected and a 5 ㎛ Parylene-C thin film was deposited. The applicability of Parylene-C coating to each material was confirmed through SEM analysis, contact angle measurement, surface roughness(Ra) measurement, and adhesion test according to ASTM standards for each specimen. Parylene-C thin film was deposited based on chemical vapor deposition (CVD), and a 5 ㎛ Parylene-C deposition process was established through trial and error. Through characteristic experiments to confirm the applicability of Parylene-C, SUS304 material, which is the easiest to apply Parylene-C coating without pretreatment was selected to develop a microneedle array based on CNC micromachining technology. The CNC micromachining process was divided into a total of 5 steps, and a microneedle array consisting of 19 needles with an inner diameter of 200 ㎛, an outer diameter of 400 ㎛, and a height of 1.4 mm was designed and manufactured. Finally, a 5 ㎛ Parylene-C coated microneedle array was developed, which presented future research directions in the field of microneedle-based drug delivery systems.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.523-532
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• 1999

Background: With the development of the molecular biological methods, studies of the early diagnosis of lung cancer and the detection in the preneoplastic state by using genetic probes in the high risk groups are widely investigated. In lung cancer, squamous cell carcinoma is considered to progress from the normal bronchial mucosa to the preneoplastic state, and finally to the invasive carcinoma. In this study, we investigated the expression of p53 and c-erbB2 in the normal bronchi and the cancer tissues in patients with squamous cell lung cancer to evaluate the possibility of using these immunohistochemical markers as the diagnostic and prognostic parameters of patients with squamous cell lung cancer. Method: The normal and cancerous bronchial tissues of 25 patients with squamous cell carcinoma of the lung, surgically resected from May 1995 to November 1996, were immunohistochemically stained with the monoclonal antibodies to p53(DAKO-p53) and c-erbB2(phamingen 15821A) respectively. We compared the expression status of these markers between the normal bronchial mucosa and the tumor tissue, and also investigated the relationship between the expression status of these markers in tumor tissues and the pathological stage, and the survival time. Results: The pathological stage was as follows; stage I, II were found in 5 patients respectively, stage IIIA was in 8 patients, stage IIIB was in 4 patients, and stage IV was in 3 patients. The expression rate of p53 in the squamous cell lung cancer was 48%, and it was not expressed in the normal bronchial mucosa. The expression status was increased as the pathological stage advanced(p=0.0091 by test of trend). But there were no relationship between the expression of p53 and the median survival time. C-erbB2 did not yield a significantly meaningful result. Conclusion: p53 was not found in the normal bronchial mucosa, but it was expressed in 48% of the tumor tissue. And the expression rate increased as the pathological stage advanced. So it would be helpful to apply the immunochistochemical stain with p53 in the bronchial biopsy specimen in the early diagnosis trial or staging of squamous cell lung cancer.