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The aim of this study was to investigate the possibility of chitosan and regenerated silk fibroin (CS/ RSF) blended films as novel biomaterials for daily disposable therapeutic contact lenses based ophthalmic drug delivery system. Diclofenac sodium (DS), a hydrophilic anti-inflammatory agent, was loaded into CS/RSF films by a soaking method. The best conditions of DS loading manifested the loading time of 2 h and pH 6.5 of drug solution. The drug loading capacity and the drug release profile could be controlled by varying the film RSF content. With increasing the film RSF content from 0 to 30%, the amount of loaded DS increased from 12 to 23 mg. Furthermore, the prolong drug released within therapeutic level was obtained with increasing the film RSF content. Consequently, a fast released characteristic within a therapeutic level up to 3 h was observed with the 100CS/0RSF film. On the other hand, the 70CS/30RSF film demonstrated a significant prolonged drug release within therapeutic level up to 11 h. In conclusion, the CS/RSF films are promising as novel biomaterials for daily disposable therapeutic contact lenses-based ophthalmic delivery.

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The possibility use of near‐infrared (NIR) spectroscopy in the region of 9000–4000 cm−1 to determine total bacterial count (TBC) in raw milk and the influence of bacterial cultivation on TBC prediction accuracy were studied. Raw milk samples were diluted 10‐fold with tryptic soy broth and then cultivated at 32 °C for 2 hr. NIR measurements were performed after cultivation times of 30, 60, 90, and 120 min. Partial least squares regression was used to develop calibration models for TBC. The best calibration result was obtained from the 90 min‐cultivation samples, with the correlation coefficient (R) of .90 and root mean square error of prediction of .32 log10 CFU/ml. The analysis of the calibration structure indicated that important information for TBC prediction was from chemical compositional changes and bacterial metabolites. The NIR method combined with bacterial cultivation was satisfactory for the rapid analysis of TBC in raw milk. Practical applications The number of bacteria in raw milk is an important indicator for hygienic quality and milk grading system which consequently reflects a milk price. The proposed method allows satisfied performance for TBC determination in raw milk in 90 min as compared to the 48 hr required using the plate count method. The NIR method developed in this study seems to be an effective tool for a rapid evaluation of bacterial contamination in raw milk. An integration between determination of milk hygienic quality and chemical compositional quality using NIR spectroscopy will facilitate a rapid and multicomponents analysis and become a powerful tool for a practical use in the competitive dairy industry.