The best condition to produce smooth polyvinyl chloride (PVC, M.W. ∼6.4×10⁴ g/mol) fibers (572±171 nm) was 10 % w/v PVC in a mixture of tetrahydrofuran and dimethyl sulfoxide (4:1 by volume) with 5 % w/w Tween 20, 15 kV, 10 cm, and 3 ml/h. PVC fibers were subjected to plasma surface treatment to make them more hydrophilic. Diameters of the treated fibers were 549±99 nm. Next, the PVC fibers were treated with ethylene diamine (EDA) and p-phenylenediamine (PDA) to obtain PVC-EDA and PVC-PDA, respectively. Bromelain was immobilized onto PVC-EDA and PVC-PDA by an aid of 1 % w/v glutaraldehyde to receive PVC-EDA-bromelain and PVC-PDA-bromelain with good tensile strengths of ∼19 and ∼14 MPa, respectively. The activities of free and immobilized bromelain were assayed by casein as a substrate and a spectrophotometer at 275 nm. Bromelain loadings on PVC-EDA-bromelain and PVC-PDA-bromelain were 88.10±3.54 and 36.38±18.10 mg/g of fibers, respectively. The kinetic activities of bromelain, PVC-EDA-bromelain, and PVC-PDA-bromelain were 11.31±2.17, 0.31±0.03, and 2.15±1.34 min⁻¹, respectively. PVC-EDA-bromelain and PVC-PDA-bromelain could be reused at least 9 times with > 50 % relative activities and endured heat (50–90 °C) better than free bromelain did. Their relative activities were > 70 % after storage at 90 °C for 20 min.

生产光滑的聚氯乙烯（PVC，MW〜6.4×10 ⁴ g / mol）纤维（572±171 nm）的最佳条件是在四氢呋喃和二甲亚砜（体积比为4：1）的混合物中使用10％w / v PVC含5％w / w的Tween 20、15 kV，10 cm和3 ml / h。对PVC纤维进行了等离子表面处理，使其更具亲水性。处理的纤维的直径为549±99nm。接着，将PVC纤维用乙二胺（EDA）和p-苯二胺（PDA）分别获得PVC-EDA和PVC-PDA。借助1％w / v戊二醛将菠萝蛋白酶固定在PVC-EDA和PVC-PDA上，分别得到抗拉伸强度分别约为19 MPa和14 MPa的PVC-EDA-bromelain和PVC-PDA-bromelain。用酪蛋白作为底物和分光光度计在275 nm处测定游离和固定的菠萝蛋白酶的活性。PVC-EDA-bromelain和PVC-PDA-bromelain上的菠萝蛋白酶负载量分别为88.10±3.54和36.38±18.10 mg / g纤维。菠萝蛋白酶，PVC-EDA-bromelain和PVC-PDA-bromelain的动力学活性分别为11.31±2.17、0.31±0.03和2.15±1.34 min ^-1， 分别。PVC-EDA-bromelain和PVC-PDA-bromelain可以重复使用至少9次，相对活性> 50％，耐热性（50-90°C）比游离菠萝蛋白酶更好。在90°C下储存20分钟后，它们的相对活性> 70％。